nautilus-execution 0.57.0

// -------------------------------------------------------------------------------------------------
//  Copyright (C) 2015-2026 Nautech Systems Pty Ltd. All rights reserved.
//  https://nautechsystems.io
//
//  Licensed under the GNU Lesser General Public License Version 3.0 (the "License");
//  You may not use this file except in compliance with the License.
//  You may obtain a copy of the License at https://www.gnu.org/licenses/lgpl-3.0.en.html
//
//  Unless required by applicable law or agreed to in writing, software
//  distributed under the License is distributed on an "AS IS" BASIS,
//  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
//  See the License for the specific language governing permissions and
//  limitations under the License.
// -------------------------------------------------------------------------------------------------

//! Tests module for `ExecutionEngine`.

use std::{
    cell::RefCell,
    collections::HashSet,
    future::Future,
    pin::pin,
    rc::Rc,
    str::FromStr,
    task::{Context, Poll, Waker},
};

use ahash::AHashSet;
use nautilus_common::{
    cache::{Cache, CacheSnapshotRef},
    clients::ExecutionClient,
    clock::{self, Clock, TestClock},
    messages::{
        ExecutionReport,
        execution::{
            CancelAllOrders, CancelOrder, ModifyOrder, SubmitOrder, SubmitOrderList, TradingCommand,
        },
    },
    msgbus::{
        self, MessageBus, MessagingSwitchboard, TypedHandler, stubs::get_any_saving_handler,
        switchboard,
    },
};
use nautilus_core::{UUID4, UnixNanos, datetime::NANOSECONDS_IN_MINUTE};
use nautilus_execution::engine::{
    ExecutionEngine, config::ExecutionEngineConfig, stubs::StubExecutionClient,
};
use nautilus_model::{
    accounts::CashAccount,
    enums::{
        AccountType, ContingencyType, LiquiditySide, OmsType, OrderSide, OrderStatus, OrderType,
        PositionSide, PositionSideSpecified, TimeInForce, TriggerType,
    },
    events::{
        AccountState, OrderCanceled, OrderEventAny, OrderFilled, OrderPendingUpdate, OrderUpdated,
    },
    identifiers::{
        AccountId, ClientId, ClientOrderId, ExecAlgorithmId, InstrumentId, OrderListId, PositionId,
        StrategyId, TradeId, TraderId, Venue, VenueOrderId,
    },
    instruments::{CurrencyPair, Instrument, InstrumentAny, stubs::audusd_sim},
    orders::{Order, OrderAny, OrderList, builder::OrderTestBuilder, stubs::TestOrderEventStubs},
    position::Position,
    reports::{ExecutionMassStatus, FillReport, OrderStatusReport, PositionStatusReport},
    stubs::{TestDefault, stub_position_long},
    types::{AccountBalance, Currency, Money, Price, Quantity},
};
use rstest::*;
use rust_decimal::Decimal;
use rust_decimal_macros::dec;

#[fixture]
fn test_clock() -> Rc<RefCell<dyn clock::Clock>> {
    Rc::new(RefCell::new(TestClock::new()))
}

#[fixture]
fn test_cache() -> Rc<RefCell<Cache>> {
    Rc::new(RefCell::new(Cache::default()))
}

#[fixture]
fn execution_engine() -> ExecutionEngine {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));

    ExecutionEngine::new(clock, cache, None)
}

#[fixture]
fn execution_engine_with_config() -> ExecutionEngine {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        debug: true,
        snapshot_orders: true,
        snapshot_positions: true,
        manage_own_order_books: false,
        ..Default::default()
    };

    ExecutionEngine::new(clock, cache, Some(config))
}

#[fixture]
fn stub_client() -> StubExecutionClient {
    StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::from("TEST-ACCOUNT"),
        Venue::test_default(),
        OmsType::Netting,
        None,
    )
}

#[rstest]
fn test_register_client_success(
    mut execution_engine: ExecutionEngine,
    stub_client: StubExecutionClient,
) {
    let client_id = stub_client.client_id();

    let result = execution_engine.register_client(Box::new(stub_client));

    assert!(
        result.is_ok(),
        "Failed to register client: {:?}",
        result.err()
    );
    assert!(
        execution_engine.get_client(&client_id).is_some(),
        "Client should be registered and retrievable"
    );
}

#[rstest]
fn test_client_ids_preserve_registration_order(mut execution_engine: ExecutionEngine) {
    // Pin IndexMap iteration order on ExecutionEngine.clients: client_ids() drives
    // routing dispatch via get_clients_for_orders, so the registration order must
    // appear in the returned Vec across runs.
    for (id, venue) in [
        ("ZULU", Venue::from("ZULU")),
        ("ALPHA", Venue::from("ALPHA")),
        ("MIKE", Venue::from("MIKE")),
    ] {
        let client = StubExecutionClient::new(
            ClientId::from(id),
            AccountId::from("TEST-ACCOUNT"),
            venue,
            OmsType::Netting,
            None,
        );
        execution_engine.register_client(Box::new(client)).unwrap();
    }

    let ids = execution_engine.client_ids();

    assert_eq!(
        ids,
        vec![
            ClientId::from("ZULU"),
            ClientId::from("ALPHA"),
            ClientId::from("MIKE"),
        ],
    );
}

#[rstest]
fn test_register_venue_routing_success(
    mut execution_engine: ExecutionEngine,
    stub_client: StubExecutionClient,
) {
    let client_id = stub_client.client_id();
    let venue = Venue::test_default();

    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let result = execution_engine.register_venue_routing(client_id, venue);

    assert!(
        result.is_ok(),
        "Failed to register venue routing: {:?}",
        result.err()
    );
    assert!(
        execution_engine.get_client(&client_id).is_some(),
        "Client should still be registered after venue routing"
    );
}

#[rstest]
fn test_subscribe_venue_instruments_delivers_to_client_adapter(
    mut execution_engine: ExecutionEngine,
    stub_client: StubExecutionClient,
) {
    // Reset the thread-local bus so prior tests on this thread cannot leak
    // instrument handlers into this assertion.
    *msgbus::get_message_bus().borrow_mut() = MessageBus::default();

    let venue = Venue::test_default();
    let received = stub_client.received_instruments();
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let engine_rc = Rc::new(RefCell::new(execution_engine));
    ExecutionEngine::subscribe_venue_instruments(&engine_rc, venue);

    let instrument = InstrumentAny::CurrencyPair(audusd_sim());
    let topic = switchboard::get_instrument_topic(instrument.id());
    msgbus::publish_instrument(topic, &instrument);

    let received = received.borrow();
    assert_eq!(received.len(), 1);
    assert_eq!(received[0].id(), instrument.id());
}

#[rstest]
fn test_deregister_client_removes_client(
    mut execution_engine: ExecutionEngine,
    stub_client: StubExecutionClient,
) {
    let client_id = stub_client.client_id();
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    assert!(
        execution_engine.get_client(&client_id).is_some(),
        "Client should be registered initially"
    );

    let result = execution_engine.deregister_client(client_id);

    assert!(
        result.is_ok(),
        "Failed to deregister client: {:?}",
        result.err()
    );
    assert!(
        execution_engine.get_client(&client_id).is_none(),
        "Client should be removed after deregistration"
    );
}

#[rstest]
fn test_check_connected_when_client_connected_returns_true(mut execution_engine: ExecutionEngine) {
    let mut stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::from("TEST-ACCOUNT"),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );

    // Start the client before registering to ensure is_connected = true
    stub_client.start().unwrap();
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let is_connected = execution_engine.check_connected();

    assert!(is_connected, "Should return true when client is connected");
}

#[rstest]
fn test_check_connected_when_client_disconnected_returns_false(
    mut execution_engine: ExecutionEngine,
) {
    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::from("TEST-ACCOUNT"),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );

    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let is_connected = execution_engine.check_connected();

    assert!(
        !is_connected,
        "Should return false when client is disconnected"
    );
}

#[rstest]
fn test_check_disconnected_when_client_disconnected_returns_true(
    mut execution_engine: ExecutionEngine,
) {
    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::from("TEST-ACCOUNT"),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );

    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let is_disconnected = execution_engine.check_disconnected();

    assert!(
        is_disconnected,
        "Should return true when client is disconnected"
    );
}

#[rstest]
fn test_check_integrity_returns_true(execution_engine: ExecutionEngine) {
    let integrity_check = execution_engine.check_integrity();

    assert!(
        integrity_check,
        "Integrity check should pass for new execution engine"
    );
}

#[rstest]
fn test_execution_engine_with_config_initializes_correctly(
    execution_engine_with_config: ExecutionEngine,
) {
    let integrity_check = execution_engine_with_config.check_integrity();
    assert!(integrity_check);
}

#[rstest]
fn test_set_position_id_counts_updates_correctly(mut execution_engine: ExecutionEngine) {
    let instrument = audusd_sim();
    let position = stub_position_long(instrument);
    let strategy_id = position.strategy_id;

    execution_engine
        .cache()
        .borrow_mut()
        .add_position(&position, OmsType::Netting)
        .unwrap();

    execution_engine.set_position_id_counts();

    let actual_count = execution_engine.position_id_count(strategy_id);
    assert_eq!(
        actual_count, 1,
        "Expected position ID count to be 1 for strategy_id {strategy_id:?}, but got {actual_count}"
    );
}

#[rstest]
fn test_execution_engine_default_config_initializes_correctly(execution_engine: ExecutionEngine) {
    let integrity_check = execution_engine.check_integrity();
    assert!(integrity_check);
}

#[rstest]
fn test_counters_increment_and_reset(mut execution_engine: ExecutionEngine) {
    assert_eq!(execution_engine.command_count(), 0);
    assert_eq!(execution_engine.event_count(), 0);
    assert_eq!(execution_engine.report_count(), 0);

    let instrument_id = audusd_sim().id();
    let command = CancelAllOrders::new(
        TraderId::test_default(),
        None,
        StrategyId::test_default(),
        instrument_id,
        OrderSide::NoOrderSide,
        UUID4::new(),
        UnixNanos::default(),
        None,
    );
    execution_engine.execute(TradingCommand::CancelAllOrders(command));

    let order = OrderTestBuilder::new(OrderType::Market)
        .instrument_id(instrument_id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(1))
        .build();
    let event = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&event);

    let report = create_order_status_report(
        Some(ClientOrderId::from("O-001")),
        VenueOrderId::from("V-001"),
        instrument_id,
        OrderStatus::Accepted,
        Quantity::from(1),
        Quantity::from(0),
    );
    execution_engine.reconcile_execution_report(&ExecutionReport::Order(Box::new(report)));

    assert_eq!(execution_engine.command_count(), 1);
    assert_eq!(execution_engine.event_count(), 1);
    assert_eq!(execution_engine.report_count(), 1);

    execution_engine.reset();

    assert_eq!(execution_engine.command_count(), 0);
    assert_eq!(execution_engine.event_count(), 0);
    assert_eq!(execution_engine.report_count(), 0);
}

#[rstest]
fn test_submit_order_denied_with_custom_position_id_under_netting(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::from("TEST-ACCOUNT"),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .quantity(Quantity::from(100_000))
        .build();

    let custom_position_id = PositionId::new(format!("{}-GRID", instrument.id));

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(
            order.clone(),
            Some(custom_position_id),
            Some(ClientId::from("STUB")),
            true,
        )
        .unwrap();

    let submit_order = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order.client_order_id(),
        order_init: order.init_event().clone(),
        position_id: Some(custom_position_id),
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    execution_engine.execute(TradingCommand::SubmitOrder(submit_order));

    let cache = execution_engine.cache().borrow();
    let cached_order = cache
        .order(&order.client_order_id())
        .expect("Order should be cached");

    assert_eq!(cached_order.status(), OrderStatus::Denied);
}

#[rstest]
fn test_submit_order_list_denied_with_custom_position_id_under_netting(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::from("TEST-ACCOUNT"),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let entry = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-19700101-000000-002-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    let stop_loss = OrderTestBuilder::new(OrderType::StopMarket)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-19700101-000000-002-002-1"))
        .side(OrderSide::Sell)
        .quantity(Quantity::from(100_000))
        .trigger_price(Price::from_str("0.50000").unwrap())
        .build();

    let take_profit = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-19700101-000000-002-003-1"))
        .side(OrderSide::Sell)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("1.00000").unwrap())
        .build();

    let orders = [entry.clone(), stop_loss.clone(), take_profit.clone()];
    let custom_position_id = PositionId::new(format!("{}-GRID", instrument.id));

    for order in &orders {
        execution_engine
            .cache()
            .borrow_mut()
            .add_order(
                order.clone(),
                Some(custom_position_id),
                Some(ClientId::from("STUB")),
                true,
            )
            .unwrap();
    }

    let order_list = OrderList::new(
        OrderListId::from("L-001"),
        instrument.id,
        strategy_id,
        vec![
            entry.client_order_id(),
            stop_loss.client_order_id(),
            take_profit.client_order_id(),
        ],
        UnixNanos::default(),
    );

    let submit_order_list = SubmitOrderList {
        trader_id,
        client_id: Some(ClientId::from("STUB")),
        strategy_id,
        instrument_id: instrument.id,
        order_list,
        order_inits: orders.iter().map(|o| o.init_event().clone()).collect(),
        exec_algorithm_id: None,
        position_id: Some(custom_position_id),
        params: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    execution_engine.execute(TradingCommand::SubmitOrderList(submit_order_list));

    let cache = execution_engine.cache().borrow();
    for order in &orders {
        let cached = cache
            .order(&order.client_order_id())
            .expect("Order should be cached");
        assert_eq!(cached.status(), OrderStatus::Denied);
    }
}

#[rstest]
fn test_submit_order_denied_with_unspecified_strategy_oms_and_netting_client(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::from("TEST-ACCOUNT"),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    // Strategy registered with UNSPECIFIED; resolution must fall through to the
    // routed client's NETTING OMS.
    execution_engine.register_oms_type(strategy_id, OmsType::Unspecified);

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .quantity(Quantity::from(100_000))
        .build();

    let custom_position_id = PositionId::new(format!("{}-GRID", instrument.id));

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(
            order.clone(),
            Some(custom_position_id),
            Some(ClientId::from("STUB")),
            true,
        )
        .unwrap();

    let submit_order = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order.client_order_id(),
        order_init: order.init_event().clone(),
        position_id: Some(custom_position_id),
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    execution_engine.execute(TradingCommand::SubmitOrder(submit_order));

    let cache = execution_engine.cache().borrow();
    let cached_order = cache
        .order(&order.client_order_id())
        .expect("Order should be cached");

    assert_eq!(cached_order.status(), OrderStatus::Denied);
}

#[rstest]
fn test_submit_order_with_duplicate_client_order_id_handles_gracefully(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::from("TEST-ACCOUNT"),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let submit_order = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order.client_order_id(),
        order_init: order.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    execution_engine.execute(TradingCommand::SubmitOrder(submit_order.clone()));

    let order_submitted_event = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&order_submitted_event);
    execution_engine.execute(TradingCommand::SubmitOrder(submit_order));

    assert!(
        execution_engine
            .cache()
            .borrow()
            .order_exists(&order.client_order_id()),
        "Order should exist in cache"
    );

    let cache = execution_engine.cache().borrow();
    let cached_order = cache
        .order(&order.client_order_id())
        .expect("Order should be cached");

    assert_eq!(
        cached_order.status(),
        OrderStatus::Submitted,
        "Order should be in Submitted status"
    );
    assert_eq!(
        cached_order.client_order_id(),
        order.client_order_id(),
        "Cached order should have correct client order ID"
    );
}

#[rstest]
fn test_submit_order_for_random_venue_logs(mut execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(), // Use SIM venue to match instrument
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();
    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-19700101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(10))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(
            order.clone(),
            None,
            Some(ClientId::from("RANDOM_VENUE")),
            true,
        )
        .unwrap();

    // This will test the scenario where no specific routing exists
    let submit_order = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order.client_order_id(),
        order_init: order.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("RANDOM_VENUE")), // No client registered with this ID
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };
    // This should find the client by venue routing since instrument is AUD/USD.SIM
    execution_engine.execute(TradingCommand::SubmitOrder(submit_order));
    let cache = execution_engine.cache().borrow();
    assert!(
        cache.order_exists(&order.client_order_id()),
        "Order should be added to cache when client routing is available"
    );

    // Order status should remain INITIALIZED since the stub client doesn't generate events
    assert_eq!(
        order.status(),
        OrderStatus::Initialized,
        "Order status should remain INITIALIZED with stub client"
    );
}

#[rstest]
fn test_order_filled_with_unrecognized_strategy_id(mut execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();
    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-19700101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let order_submitted_event = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&order_submitted_event);

    let different_strategy_id = StrategyId::from("RANDOM-001");
    let order_filled_event = OrderFilled::new(
        trader_id,
        different_strategy_id, // Different strategy ID from the order - this will cause panic
        instrument.id,
        order.client_order_id(),
        VenueOrderId::from("V-001"),
        AccountId::test_default(),
        TradeId::new("T-001"),
        order.order_side(),
        order.order_type(),
        order.quantity(),
        Price::from_str("1.0").unwrap(),
        instrument.quote_currency(),
        LiquiditySide::Maker,
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false,
        None,
        Some(Money::from("2 USD")),
    );
    // This should now log an error instead of panicking
    execution_engine.process(&OrderEventAny::Filled(order_filled_event));
    let cache = execution_engine.cache().borrow();
    let updated_order = cache.order(&order.client_order_id()).unwrap();
    assert_eq!(
        updated_order.status(),
        OrderStatus::Submitted,
        "Order should remain SUBMITTED when filled event has mismatched strategy_id"
    );
}

#[rstest]
fn test_process_filled_order_publishes_order_fills_topic(mut execution_engine: ExecutionEngine) {
    let (instrument, order) = prepare_accepted_order(&mut execution_engine);
    let fills_topic = switchboard::get_order_fills_topic(instrument.id());
    let order_topic = switchboard::get_event_orders_topic(order.strategy_id());
    let received = Rc::new(RefCell::new(Vec::<OrderEventAny>::new()));
    let topics = Rc::new(RefCell::new(Vec::<&'static str>::new()));
    let fills_handler = TypedHandler::from({
        let received = received.clone();
        let topics = topics.clone();
        move |event: &OrderEventAny| {
            topics.borrow_mut().push("fills");
            received.borrow_mut().push(event.clone());
        }
    });
    let order_handler = TypedHandler::from({
        let topics = topics.clone();
        move |_event: &OrderEventAny| {
            topics.borrow_mut().push("orders");
        }
    });
    msgbus::subscribe_order_events(fills_topic.into(), fills_handler.clone(), None);
    msgbus::subscribe_order_events(order_topic.into(), order_handler.clone(), None);

    let event = OrderEventAny::Filled(OrderFilled::new(
        order.trader_id(),
        order.strategy_id(),
        instrument.id(),
        order.client_order_id(),
        VenueOrderId::from("V-001"),
        AccountId::test_default(),
        TradeId::new("T-001"),
        order.order_side(),
        order.order_type(),
        order.quantity(),
        Price::from_str("1.0").unwrap(),
        instrument.quote_currency(),
        LiquiditySide::Maker,
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false,
        None,
        Some(Money::from("2 USD")),
    ));

    execution_engine.process(&event);
    msgbus::unsubscribe_order_events(fills_topic.into(), &fills_handler);
    msgbus::unsubscribe_order_events(order_topic.into(), &order_handler);

    let received = received.borrow();
    assert_eq!(received.len(), 1);
    assert!(matches!(received[0], OrderEventAny::Filled(_)));
    assert_eq!(received[0].client_order_id(), order.client_order_id());
    assert_eq!(received[0].instrument_id(), instrument.id());
    assert_eq!(topics.borrow().as_slice(), ["fills", "orders"]);
}

#[rstest]
fn test_process_canceled_order_publishes_order_cancels_topic(
    mut execution_engine: ExecutionEngine,
) {
    let (instrument, order) = prepare_accepted_order(&mut execution_engine);
    let cancels_topic = switchboard::get_order_cancels_topic(instrument.id());
    let order_topic = switchboard::get_event_orders_topic(order.strategy_id());
    let received = Rc::new(RefCell::new(Vec::<OrderEventAny>::new()));
    let topics = Rc::new(RefCell::new(Vec::<&'static str>::new()));
    let cancels_handler = TypedHandler::from({
        let received = received.clone();
        let topics = topics.clone();
        move |event: &OrderEventAny| {
            topics.borrow_mut().push("cancels");
            received.borrow_mut().push(event.clone());
        }
    });
    let order_handler = TypedHandler::from({
        let topics = topics.clone();
        move |_event: &OrderEventAny| {
            topics.borrow_mut().push("orders");
        }
    });
    msgbus::subscribe_order_events(cancels_topic.into(), cancels_handler.clone(), None);
    msgbus::subscribe_order_events(order_topic.into(), order_handler.clone(), None);

    let event = TestOrderEventStubs::canceled(
        &order,
        AccountId::test_default(),
        Some(VenueOrderId::from("V-001")),
    );

    execution_engine.process(&event);
    msgbus::unsubscribe_order_events(cancels_topic.into(), &cancels_handler);
    msgbus::unsubscribe_order_events(order_topic.into(), &order_handler);

    let received = received.borrow();
    assert_eq!(received.len(), 1);
    assert!(matches!(received[0], OrderEventAny::Canceled(_)));
    assert_eq!(received[0].client_order_id(), order.client_order_id());
    assert_eq!(received[0].instrument_id(), instrument.id());
    assert_eq!(topics.borrow().as_slice(), ["orders", "cancels"]);
}

fn prepare_accepted_order(execution_engine: &mut ExecutionEngine) -> (InstrumentAny, OrderAny) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = InstrumentAny::from(audusd_sim());

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone())
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_account(CashAccount::default().into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id())
        .client_order_id(ClientOrderId::from("O-19700101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let submitted = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&submitted);

    let accepted = TestOrderEventStubs::accepted(
        &order,
        AccountId::test_default(),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&accepted);

    (instrument, order)
}

#[rstest]
fn test_submit_bracket_order_list_with_all_duplicate_client_order_id_logs_does_not_submit(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let entry = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-19700101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    let stop_loss = OrderTestBuilder::new(OrderType::StopMarket)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-19700101-000000-001-002-1"))
        .side(OrderSide::Sell)
        .quantity(Quantity::from(100_000))
        .trigger_price(Price::from_str("0.50000").unwrap())
        .build();

    let take_profit = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-19700101-000000-001-003-1"))
        .side(OrderSide::Sell)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("1.00000").unwrap())
        .build();

    let orders = [entry.clone(), stop_loss.clone(), take_profit.clone()];
    let order_list = OrderList::new(
        OrderListId::from("1"),
        instrument.id,
        strategy_id,
        vec![
            entry.client_order_id(),
            stop_loss.client_order_id(),
            take_profit.client_order_id(),
        ],
        UnixNanos::default(),
    );

    let submit_order_list = SubmitOrderList {
        trader_id,
        client_id: Some(ClientId::from("STUB")),
        strategy_id,
        instrument_id: instrument.id,
        order_list,
        order_inits: orders.iter().map(|o| o.init_event().clone()).collect(),
        exec_algorithm_id: None,
        position_id: None,
        params: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    // Insert orders into cache (simulating what the strategy does)
    for order in &orders {
        execution_engine
            .cache()
            .borrow_mut()
            .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
            .unwrap();
    }

    execution_engine.execute(TradingCommand::SubmitOrderList(submit_order_list.clone()));
    let entry_submitted = TestOrderEventStubs::submitted(&entry, AccountId::test_default());
    execution_engine.process(&entry_submitted);

    let stop_loss_submitted = TestOrderEventStubs::submitted(&stop_loss, AccountId::test_default());
    execution_engine.process(&stop_loss_submitted);

    let take_profit_submitted =
        TestOrderEventStubs::submitted(&take_profit, AccountId::test_default());
    execution_engine.process(&take_profit_submitted);

    // Get updated orders from cache after submitted events
    let cache = execution_engine.cache().borrow();
    let entry_updated = cache
        .order(&entry.client_order_id())
        .expect("Entry order should exist")
        .clone();
    let stop_loss_updated = cache
        .order(&stop_loss.client_order_id())
        .expect("Stop loss order should exist")
        .clone();
    let take_profit_updated = cache
        .order(&take_profit.client_order_id())
        .expect("Take profit order should exist")
        .clone();
    drop(cache);
    execution_engine.execute(TradingCommand::SubmitOrderList(submit_order_list));
    assert_eq!(
        entry_updated.status(),
        OrderStatus::Submitted,
        "Entry order should remain SUBMITTED (not invalidated by duplicate)"
    );

    assert_eq!(
        stop_loss_updated.status(),
        OrderStatus::Submitted,
        "Stop loss order should remain SUBMITTED (not invalidated by duplicate)"
    );

    assert_eq!(
        take_profit_updated.status(),
        OrderStatus::Submitted,
        "Take profit order should remain SUBMITTED (not invalidated by duplicate)"
    );
    let cache = execution_engine.cache().borrow();
    assert!(
        cache.order_exists(&entry.client_order_id()),
        "Entry order should exist in cache"
    );
    assert!(
        cache.order_exists(&stop_loss.client_order_id()),
        "Stop loss order should exist in cache"
    );
    assert!(
        cache.order_exists(&take_profit.client_order_id()),
        "Take profit order should exist in cache"
    );

    // Note: In the Python test, it checks command_count == 2, meaning only 2 commands were processed
    // This suggests the duplicate submission was handled gracefully without creating new orders
}

#[rstest]
fn test_submit_order_successfully_processes_and_caches_order(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::from("TEST-ACCOUNT"),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let submit_order = SubmitOrder {
        trader_id,
        strategy_id,
        position_id: None,
        params: None,
        client_order_id: order.client_order_id(),
        order_init: order.init_event().clone(),
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
        client_id: Some(ClientId::from("STUB")),
        instrument_id: instrument.id,
        exec_algorithm_id: None,
    };
    execution_engine.execute(TradingCommand::SubmitOrder(submit_order));
    let cache = execution_engine.cache().borrow();
    assert!(
        cache.order_exists(&order.client_order_id()),
        "Order should exist in cache after submission"
    );
    let cached_order = cache
        .order(&order.client_order_id())
        .expect("Order should be retrievable from cache");

    assert_eq!(
        cached_order.trader_id(),
        trader_id,
        "Cached order should have correct trader ID"
    );

    assert_eq!(
        cached_order.strategy_id(),
        strategy_id,
        "Cached order should have correct strategy ID"
    );

    assert_eq!(
        cached_order.instrument_id(),
        instrument.id,
        "Cached order should have correct instrument ID"
    );

    assert_eq!(
        cached_order.quantity(),
        Quantity::from(100_000),
        "Cached order should have correct quantity"
    );
    // Note: In a real implementation, we would verify the client was called
    // For now, we verify the order was processed without errors
    assert_eq!(
        cached_order.status(),
        OrderStatus::Initialized,
        "Order should be in Initialized status after submission"
    );
}

#[rstest]
fn test_submit_order_with_cleared_cache_logs_error(mut execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();
    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-19700101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let submit_order = SubmitOrder {
        trader_id,
        client_id: Some(ClientId::from("STUB")),
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order.client_order_id(),
        order_init: order.init_event().clone(),
        exec_algorithm_id: None,
        position_id: None,
        params: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };
    execution_engine.execute(TradingCommand::SubmitOrder(submit_order));
    assert!(
        execution_engine
            .cache()
            .borrow()
            .order_exists(&order.client_order_id()),
        "Order should be added to cache after submission"
    );

    // Clear the cache (equivalent to self.cache.reset() in Python)
    execution_engine.cache().borrow_mut().reset();
    assert!(
        !execution_engine
            .cache()
            .borrow()
            .order_exists(&order.client_order_id()),
        "Order should no longer exist in cache after clearing"
    );

    let order_accepted_event = TestOrderEventStubs::accepted(
        &order,
        AccountId::test_default(),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order_accepted_event);
    assert_eq!(
        order.status(),
        OrderStatus::Initialized,
        "Order status should remain INITIALIZED when cache is cleared"
    );
    assert!(
        !execution_engine
            .cache()
            .borrow()
            .order_exists(&order.client_order_id()),
        "Order should remain absent from cache"
    );
}

#[rstest]
fn test_when_applying_event_to_order_with_invalid_state_trigger_logs(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();
    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-19700101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let submit_order = SubmitOrder {
        trader_id,
        client_id: Some(ClientId::from("STUB")),
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order.client_order_id(),
        order_init: order.init_event().clone(),
        exec_algorithm_id: None,
        position_id: None,
        params: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };
    execution_engine.execute(TradingCommand::SubmitOrder(submit_order));
    assert!(
        execution_engine
            .cache()
            .borrow()
            .order_exists(&order.client_order_id()),
        "Order should be added to cache after submission"
    );

    // Try to fill order before it's been accepted (invalid state transition)
    let order_filled_event = TestOrderEventStubs::filled(
        &order,
        &instrument.into(),
        Some(TradeId::new("E-19700101-000000-001-001")),
        None,
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );

    // This should log an error and not change the order status
    execution_engine.process(&order_filled_event);
    assert_eq!(
        order.status(),
        OrderStatus::Initialized,
        "Order status should remain INITIALIZED when invalid event is applied"
    );
}

#[rstest]
fn test_order_filled_event_when_order_not_found_in_cache_logs(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-19700101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();
    assert!(
        !execution_engine
            .cache()
            .borrow()
            .order_exists(&order.client_order_id()),
        "Order should not exist in cache"
    );
    let order_filled_event = TestOrderEventStubs::filled(
        &order,
        &instrument.into(),
        Some(TradeId::new("E-19700101-000000-001-001")),
        None,
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );

    execution_engine.process(&order_filled_event);
    assert_eq!(
        order.status(),
        OrderStatus::Initialized,
        "Order status should remain INITIALIZED when order not found in cache"
    );
    assert!(
        !execution_engine
            .cache()
            .borrow()
            .order_exists(&order.client_order_id()),
        "Order should still not exist in cache"
    );
}

#[rstest]
fn test_cancel_order_for_already_closed_order_logs_and_does_nothing(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();
    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-19700101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), false)
        .unwrap();

    let submit_order = SubmitOrder {
        trader_id,
        client_id: Some(ClientId::from("STUB")),
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order.client_order_id(),
        order_init: order.init_event().clone(),
        exec_algorithm_id: None,
        position_id: None,
        params: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    // Submit and process order through full lifecycle to FILLED status
    execution_engine.execute(TradingCommand::SubmitOrder(submit_order));

    let order_submitted_event = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&order_submitted_event);

    let order_accepted_event = TestOrderEventStubs::accepted(
        &order,
        AccountId::test_default(),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order_accepted_event);

    let order_filled_event = OrderEventAny::Filled(OrderFilled::new(
        order.trader_id(),
        order.strategy_id(),
        order.instrument_id(),
        order.client_order_id(),
        VenueOrderId::from("V-001"),
        AccountId::test_default(),
        TradeId::new("E-19700101-000000-001-001"),
        order.order_side(),
        order.order_type(),
        order.quantity(), // Fill the entire order quantity to ensure Filled status
        Price::from_str("1.0").unwrap(),
        instrument.quote_currency(),
        LiquiditySide::Maker,
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false,
        None,                       // position_id
        Some(Money::from("2 USD")), // commission
    ));
    execution_engine.process(&order_filled_event);
    let order_status = {
        let cache = execution_engine.cache().borrow();
        let cached_order = cache
            .order(&order.client_order_id())
            .expect("Order should exist in cache");
        cached_order.status()
    };
    assert_eq!(
        order_status,
        OrderStatus::Filled,
        "Order should be FILLED before cancel attempt"
    );
    let cancel_order = CancelOrder {
        trader_id,
        client_id: Some(ClientId::from("STUB")),
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order.client_order_id(),
        venue_order_id: Some(VenueOrderId::from("V-001")),
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
        params: None,
    };

    execution_engine.execute(TradingCommand::CancelOrder(cancel_order));
    let order_status_after_cancel = {
        let cache = execution_engine.cache().borrow();
        let cached_order_after_cancel = cache
            .order(&order.client_order_id())
            .expect("Order should still exist in cache");
        cached_order_after_cancel.status()
    };
    assert_eq!(
        order_status_after_cancel,
        OrderStatus::Filled,
        "Order status should remain FILLED after cancel attempt"
    );
}

#[rstest]
fn test_canceled_order_receiving_fill_event_reopens_and_completes_order(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::from("TEST-ACCOUNT"),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let order_submitted_event =
        TestOrderEventStubs::submitted(&order, AccountId::from("TEST-ACCOUNT"));
    execution_engine.process(&order_submitted_event);

    let order_accepted_event = TestOrderEventStubs::accepted(
        &order,
        AccountId::from("TEST-ACCOUNT"),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order_accepted_event);
    let accepted_order = execution_engine
        .cache()
        .borrow()
        .order(&order.client_order_id())
        .map(|o| o.clone())
        .expect("Order should exist in cache");
    assert!(
        accepted_order.venue_order_id().is_some(),
        "Order should have venue_order_id after acceptance"
    );

    let order_canceled_event = TestOrderEventStubs::canceled(
        &order,
        AccountId::from("TEST-ACCOUNT"),
        Some(VenueOrderId::from("V-001")), // Must match the accepted event
    );
    execution_engine.process(&order_canceled_event);
    let canceled_order = execution_engine
        .cache()
        .borrow()
        .order(&order.client_order_id())
        .map(|o| o.clone())
        .expect("Order should exist in cache");

    assert_eq!(
        canceled_order.status(),
        OrderStatus::Canceled,
        "Order should be in Canceled status before fill event"
    );

    assert!(
        canceled_order.is_closed(),
        "Order should be closed before fill event"
    );

    let order_filled_event = OrderEventAny::Filled(OrderFilled::new(
        order.trader_id(),
        order.strategy_id(),
        instrument.id(),
        order.client_order_id(),
        VenueOrderId::from("V-001"), // Use the same venue_order_id as the accepted event
        AccountId::from("TEST-ACCOUNT"),
        TradeId::new("E-19700101-000000-001-001-1"),
        order.order_side(),
        order.order_type(),
        order.quantity(), // last_qty: set to full order quantity to ensure Filled status
        Price::from_str("1.0").unwrap(), // last_px
        instrument.quote_currency(),
        LiquiditySide::Maker,
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false, // reconciliation
        Some(PositionId::new("1")),
        Some(Money::from("2 USD")),
    ));

    execution_engine.process(&order_filled_event);
    let cache = execution_engine.cache().borrow();
    let filled_order = cache
        .order(&order.client_order_id())
        .expect("Order should still exist in cache after fill");

    assert_eq!(
        filled_order.status(),
        OrderStatus::Filled,
        "Canceled order should transition to Filled status when receiving fill event"
    );

    assert!(
        filled_order.is_closed(),
        "Order should be closed after being filled"
    );
    assert_eq!(
        filled_order.quantity(),
        Quantity::from(100_000),
        "Order quantity should remain unchanged"
    );

    assert_eq!(
        filled_order.client_order_id(),
        order.client_order_id(),
        "Order client order ID should remain unchanged"
    );
}

#[rstest]
fn test_canceled_order_receiving_partial_fill_event_reopens_and_becomes_partially_filled(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::from("TEST-ACCOUNT"),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let order_submitted_event =
        TestOrderEventStubs::submitted(&order, AccountId::from("TEST-ACCOUNT"));
    execution_engine.process(&order_submitted_event);

    let order_accepted_event = TestOrderEventStubs::accepted(
        &order,
        AccountId::from("TEST-ACCOUNT"),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order_accepted_event);

    let order_canceled_event = TestOrderEventStubs::canceled(
        &order,
        AccountId::from("TEST-ACCOUNT"),
        Some(VenueOrderId::from("V-001")), // Must match the accepted event
    );
    execution_engine.process(&order_canceled_event);
    let canceled_order = execution_engine
        .cache()
        .borrow()
        .order(&order.client_order_id())
        .map(|o| o.clone())
        .expect("Order should exist in cache");

    assert_eq!(
        canceled_order.status(),
        OrderStatus::Canceled,
        "Order should be in Canceled status before partial fill event"
    );

    assert!(
        canceled_order.is_closed(),
        "Order should be closed before partial fill event"
    );

    let partial_fill_qty = Quantity::from(50_000); // Half of 100_000
    let order_partially_filled_event = OrderEventAny::Filled(OrderFilled::new(
        order.trader_id(),
        order.strategy_id(),
        instrument.id(),
        order.client_order_id(),
        VenueOrderId::from("V-001"), // Use the same venue_order_id as the accepted event
        AccountId::from("TEST-ACCOUNT"),
        TradeId::new("E-19700101-000000-001-001-1"),
        order.order_side(),
        order.order_type(),
        partial_fill_qty,                // Partial fill quantity
        Price::from_str("1.0").unwrap(), // last_px
        instrument.quote_currency(),
        LiquiditySide::Maker,
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false, // reconciliation
        Some(PositionId::new("1")),
        Some(Money::from("2 USD")),
    ));

    execution_engine.process(&order_partially_filled_event);
    let partially_filled_order = execution_engine
        .cache()
        .borrow()
        .order(&order.client_order_id())
        .map(|o| o.clone())
        .expect("Order should still exist in cache after partial fill");

    assert_eq!(
        partially_filled_order.status(),
        OrderStatus::PartiallyFilled,
        "Canceled order should transition to PartiallyFilled status when receiving partial fill event"
    );

    assert!(
        !partially_filled_order.is_closed(),
        "Order should be reopened (not closed) after partial fill"
    );

    assert!(
        partially_filled_order.is_open(),
        "Order should be open after partial fill"
    );
    assert_eq!(
        partially_filled_order.filled_qty(),
        partial_fill_qty,
        "Order filled quantity should match the partial fill"
    );

    assert_eq!(
        partially_filled_order.leaves_qty(),
        Quantity::from(50_000), // Remaining quantity: 100_000 - 50_000
        "Order leaves quantity should be correct after partial fill"
    );

    assert_eq!(
        partially_filled_order.quantity(),
        Quantity::from(100_000),
        "Order total quantity should remain unchanged"
    );

    assert_eq!(
        partially_filled_order.client_order_id(),
        order.client_order_id(),
        "Order client order ID should remain unchanged"
    );
}

#[rstest]
fn test_process_event_with_no_venue_order_id_logs_and_does_nothing(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::from("TEST-ACCOUNT"),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("1.0").unwrap())
        .emulation_trigger(TriggerType::BidAsk)
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let order_submitted_event =
        TestOrderEventStubs::submitted(&order, AccountId::from("TEST-ACCOUNT"));
    execution_engine.process(&order_submitted_event);

    let different_client_order_id = ClientOrderId::from("DIFFERENT-ORDER-ID");
    let order_canceled_event = OrderEventAny::Canceled(OrderCanceled::new(
        order.trader_id(),
        order.strategy_id(),
        order.instrument_id(),
        different_client_order_id, // Different client order ID
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false, // reconciliation
        None,  // venue_order_id - this is the key: no venue_order_id
        None,  // account_id
    ));
    execution_engine.process(&order_canceled_event);
    let cache = execution_engine.cache().borrow();
    let order_after = cache
        .order(&order.client_order_id())
        .expect("Order should exist in cache");

    assert_eq!(
        order_after.status(),
        OrderStatus::Submitted,
        "Order should remain in Submitted status when event has no venue_order_id"
    );
}

#[rstest]
fn test_modify_order_for_already_closed_order_logs_and_does_nothing(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::from("TEST-ACCOUNT"),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::StopMarket)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .quantity(Quantity::from(100_000))
        .trigger_price(Price::from_str("0.85101").unwrap())
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let order_submitted_event =
        TestOrderEventStubs::submitted(&order, AccountId::from("TEST-ACCOUNT"));
    execution_engine.process(&order_submitted_event);

    let order_accepted_event = TestOrderEventStubs::accepted(
        &order,
        AccountId::from("TEST-ACCOUNT"),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order_accepted_event);

    let order_filled_event = OrderEventAny::Filled(OrderFilled::new(
        order.trader_id(),
        order.strategy_id(),
        instrument.id(),
        order.client_order_id(),
        VenueOrderId::from("V-001"),
        AccountId::from("TEST-ACCOUNT"),
        TradeId::new("E-19700101-000000-001-001-1"),
        order.order_side(),
        order.order_type(),
        order.quantity(), // Full fill
        Price::from_str("1.0").unwrap(),
        instrument.quote_currency(),
        LiquiditySide::Maker,
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false, // reconciliation
        Some(PositionId::new("1")),
        Some(Money::from("2 USD")),
    ));
    execution_engine.process(&order_filled_event);
    let filled_order = execution_engine
        .cache()
        .borrow()
        .order(&order.client_order_id())
        .map(|o| o.clone())
        .expect("Order should exist in cache");

    assert_eq!(
        filled_order.status(),
        OrderStatus::Filled,
        "Order should be in Filled status before modify attempt"
    );

    assert!(
        filled_order.is_closed(),
        "Order should be closed before modify attempt"
    );

    let modify_order = ModifyOrder {
        trader_id,
        client_id: Some(ClientId::from("STUB")),
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order.client_order_id(),
        venue_order_id: order.venue_order_id(),
        quantity: Some(Quantity::from(200_000)), // Try to modify quantity
        price: None,                             // No price change
        trigger_price: order.trigger_price(),    // Keep same trigger price
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
        params: None,
    };
    execution_engine.execute(TradingCommand::ModifyOrder(modify_order));
    let cache = execution_engine.cache().borrow();
    let order_after = cache
        .order(&order.client_order_id())
        .expect("Order should still exist in cache");

    assert_eq!(
        order_after.status(),
        OrderStatus::Filled,
        "Order should remain in Filled status after modify attempt"
    );

    assert_eq!(
        order_after.quantity(),
        Quantity::from(100_000),
        "Order quantity should remain unchanged after modify attempt"
    );
}

#[rstest]
fn test_handle_order_event_with_different_client_order_id_but_matching_venue_order_id_fails_to_apply(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::from("TEST-ACCOUNT"),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let order_submitted_event =
        TestOrderEventStubs::submitted(&order, AccountId::from("TEST-ACCOUNT"));
    execution_engine.process(&order_submitted_event);

    let order_accepted_event = TestOrderEventStubs::accepted(
        &order,
        AccountId::from("TEST-ACCOUNT"),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order_accepted_event);

    let different_venue_order_id = VenueOrderId::from("DIFFERENT-V-001"); // Different venue order ID
    let order_canceled_event = OrderEventAny::Canceled(OrderCanceled::new(
        order.trader_id(),
        order.strategy_id(),
        order.instrument_id(),
        order.client_order_id(), // Same client order ID
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false,                          // reconciliation
        Some(different_venue_order_id), // Different venue_order_id
        Some(AccountId::from("TEST-ACCOUNT")),
    ));
    execution_engine.process(&order_canceled_event);
    let cache = execution_engine.cache().borrow();
    let order_after = cache
        .order(&order.client_order_id())
        .expect("Order should exist in cache");

    assert_eq!(
        order_after.status(),
        OrderStatus::Canceled,
        "Order should be canceled when client_order_id matches"
    );
}

#[rstest]
fn test_handle_order_event_with_random_client_order_id_and_order_id_not_cached(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::from("TEST-ACCOUNT"),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let order_submitted_event =
        TestOrderEventStubs::submitted(&order, AccountId::from("TEST-ACCOUNT"));
    execution_engine.process(&order_submitted_event);

    let order_accepted_event = TestOrderEventStubs::accepted(
        &order,
        AccountId::from("TEST-ACCOUNT"),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order_accepted_event);

    let random_client_order_id = ClientOrderId::from("web_001"); // Random ID from web UI
    let random_venue_order_id = VenueOrderId::from("RANDOM_001"); // Random venue order ID
    let order_canceled_event = OrderEventAny::Canceled(OrderCanceled::new(
        order.trader_id(),
        order.strategy_id(),
        order.instrument_id(),
        random_client_order_id, // Random client order ID
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false,                       // reconciliation
        Some(random_venue_order_id), // Random venue order ID
        Some(AccountId::from("TEST-ACCOUNT")),
    ));
    execution_engine.process(&order_canceled_event);
    let cache = execution_engine.cache().borrow();
    let order_after = cache
        .order(&order.client_order_id())
        .expect("Order should exist in cache");

    assert_eq!(
        order_after.status(),
        OrderStatus::Accepted,
        "Order should remain in Accepted status when event has random IDs"
    );
}

#[rstest]
fn test_handle_duplicate_order_events_logs_error_and_does_not_apply(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::from("TEST-ACCOUNT"),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let order_submitted_event =
        TestOrderEventStubs::submitted(&order, AccountId::from("TEST-ACCOUNT"));
    execution_engine.process(&order_submitted_event);

    let order_accepted_event = TestOrderEventStubs::accepted(
        &order,
        AccountId::from("TEST-ACCOUNT"),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order_accepted_event);

    let venue_order_id = VenueOrderId::from("V-001"); // Use the same venue_order_id as the accepted event
    let order_canceled_event = OrderEventAny::Canceled(OrderCanceled::new(
        order.trader_id(),
        order.strategy_id(),
        order.instrument_id(),
        order.client_order_id(), // Same client order ID
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false,                // reconciliation
        Some(venue_order_id), // Matching venue_order_id
        Some(AccountId::from("TEST-ACCOUNT")),
    ));

    execution_engine.process(&order_canceled_event);
    execution_engine.process(&order_canceled_event); // Duplicate event
    let cache = execution_engine.cache().borrow();
    let order_after = cache
        .order(&order.client_order_id())
        .expect("Order should exist in cache");

    assert_eq!(
        order_after.status(),
        OrderStatus::Canceled,
        "Order should be canceled when found by venue_order_id"
    );

    assert_eq!(
        order_after.event_count(),
        4, // Initialized + Submitted + Accepted + Canceled
        "Order should have correct event count"
    );
}

#[rstest]
fn test_handle_order_fill_event_with_no_position_id_correctly_handles_fill(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .quantity(Quantity::from(100_000))
        .build();

    // Perform setup operations sequentially with explicit borrow management
    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let order_submitted_event = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&order_submitted_event);

    let order_filled_event = TestOrderEventStubs::filled(
        &order,
        &instrument.clone().into(),
        Some(TradeId::new("E-19700101-000000-001-001")), // Provide unique trade_id
        None,                                            // position_id
        None,                                            // last_px
        None,                                            // last_qty
        None,                                            // liquidity_side
        None,                                            // commission
        None,                                            // ts_filled_ns
        Some(AccountId::test_default()),                 // account_id
    );

    execution_engine.process(&order_filled_event);
    let cache = execution_engine.cache().borrow();
    let position_ids = cache.position_ids(None, None, None, None);
    assert_eq!(position_ids.len(), 1, "Should have exactly one position");

    // Get the actual position ID that was created
    let actual_position_id = position_ids
        .iter()
        .next()
        .expect("Should have one position ID");

    // The test comment says "no position_id correctly handles fill" so the position ID
    // should be generated automatically. Verify the position was created correctly
    let position = cache
        .position(actual_position_id)
        .expect("Position should exist");

    assert!(position.is_open(), "Position should be open");

    assert!(!position.is_closed(), "Position should not be closed");

    assert_eq!(
        position.strategy_id, strategy_id,
        "Position should have correct strategy ID"
    );

    assert_eq!(
        position.instrument_id, instrument.id,
        "Position should have correct instrument ID"
    );

    assert_eq!(
        cache.positions_total_count(None, None, None, None, None),
        1,
        "Total position count should be 1"
    );

    assert_eq!(
        cache.positions_open_count(None, None, None, None, None),
        1,
        "Open position count should be 1"
    );

    assert_eq!(
        cache.positions_closed_count(None, None, None, None, None),
        0,
        "Closed position count should be 0"
    );
}

#[rstest]
fn test_handle_hedging_fill_generates_position_id_from_runtime_strategy_tag(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::from("ExampleStrategy-XNAS-T01");
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Hedging,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-T01-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let order_submitted_event = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&order_submitted_event);

    let order_accepted_event = TestOrderEventStubs::accepted(
        &order,
        AccountId::test_default(),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order_accepted_event);

    let order_filled_event = OrderEventAny::Filled(OrderFilled::new(
        trader_id,
        strategy_id,
        instrument.id,
        order.client_order_id(),
        VenueOrderId::from("V-001"),
        AccountId::test_default(),
        TradeId::new("E-19700101-000000-001-T01-1"),
        order.order_side(),
        order.order_type(),
        order.quantity(),
        Price::from_str("1.0").unwrap(),
        instrument.quote_currency(),
        LiquiditySide::Maker,
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false,
        None,
        Some(Money::from("2 USD")),
    ));
    execution_engine.process(&order_filled_event);

    let expected_position_id = PositionId::from("P-19700101-000000-001-T01-1");
    let cache = execution_engine.cache().borrow();
    let position_ids = cache.position_ids(None, None, None, None);
    assert!(
        position_ids.contains(&expected_position_id),
        "Expected {expected_position_id}, found {position_ids:?}"
    );

    let position = cache
        .position(&expected_position_id)
        .expect("Position should use the final runtime strategy tag");

    assert_eq!(position.strategy_id, strategy_id);
    assert_eq!(position.id, expected_position_id);
}

#[rstest]
fn test_handle_order_fill_event(mut execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    {
        let account = CashAccount::default();
        execution_engine
            .cache()
            .borrow_mut()
            .add_account(account.into())
            .unwrap();
    }

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let expected_position_id = PositionId::from(format!("{}-{}", instrument.id, strategy_id));

    let position = Position::new(
        &instrument.clone().into(),
        OrderFilled::new(
            order.trader_id(),
            order.strategy_id(),
            instrument.id(),
            order.client_order_id(),
            VenueOrderId::from("V-001"),
            AccountId::test_default(),
            TradeId::new("E-19700101-000000-001-001-0"), // Different trade ID
            order.order_side(),
            order.order_type(),
            order.quantity(),
            Price::from_str("1.0").unwrap(),
            instrument.quote_currency(),
            LiquiditySide::Maker,
            UUID4::new(),
            UnixNanos::default(),
            UnixNanos::default(),
            false,
            Some(expected_position_id),
            Some(Money::from("2 USD")),
        ),
    );

    execution_engine
        .cache()
        .borrow_mut()
        .add_position(&position, OmsType::Netting)
        .unwrap();

    let order_filled_event = OrderEventAny::Filled(OrderFilled::new(
        order.trader_id(),
        order.strategy_id(),
        instrument.id(),
        order.client_order_id(),
        VenueOrderId::from("V-001"),
        AccountId::test_default(),
        TradeId::new("E-19700101-000000-001-001-1"),
        order.order_side(),
        order.order_type(),
        Quantity::from(50_000),
        Price::from_str("1.0").unwrap(),
        instrument.quote_currency(),
        LiquiditySide::Maker,
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false,
        Some(expected_position_id), // ← Provide the position_id here
        Some(Money::from("2 USD")),
    ));

    execution_engine.process(&order_filled_event);
    let cache = execution_engine.cache().borrow();

    println!("Filtering parameters:");
    println!("  Venue: {:?}", Venue::test_default());
    println!("  Instrument ID: {:?}", instrument.id);
    println!("  Strategy ID: {strategy_id:?}");
    println!("  Expected Position ID: {expected_position_id:?}");

    // Also check what the position actually contains:
    let position = cache
        .position(&expected_position_id)
        .expect("Position should exist");
    println!("  Position venue: {:?}", position.instrument_id.venue);
    println!("  Position instrument: {:?}", position.instrument_id);
    println!("  Position strategy: {:?}", position.strategy_id);
    assert!(
        cache
            .position_open_ids(None, None, None, None)
            .contains(&expected_position_id),
        "Position should be in open IDs (unfiltered)"
    );

    assert!(
        cache.is_position_open(&expected_position_id),
        "Position should be open"
    );

    assert!(
        !cache.is_position_closed(&expected_position_id),
        "Position should not be closed"
    );

    let position = cache
        .position(&expected_position_id)
        .expect("Position should be retrievable");

    assert_eq!(
        position.id, expected_position_id,
        "Position should have correct ID"
    );

    assert!(
        cache
            .position_ids(None, None, None, None)
            .contains(&expected_position_id),
        "Position ID should be in position IDs list"
    );

    assert!(
        !cache
            .position_closed_ids(
                Some(&Venue::test_default()),
                Some(&instrument.id),
                Some(&strategy_id),
                None
            )
            .contains(&expected_position_id),
        "Position should not be in closed IDs for strategy"
    );

    assert!(
        !cache
            .position_closed_ids(None, None, None, None)
            .contains(&expected_position_id),
        "Position should not be in closed IDs"
    );

    assert!(
        cache
            .position_open_ids(
                Some(&Venue::test_default()),
                Some(&instrument.id),
                Some(&strategy_id),
                None
            )
            .contains(&expected_position_id),
        "Position should be in open IDs for strategy"
    );

    assert!(
        cache
            .position_open_ids(None, None, None, None)
            .contains(&expected_position_id),
        "Position should be in open IDs"
    );

    assert_eq!(
        cache.positions_total_count(None, None, None, None, None),
        1,
        "Total position count should be 1"
    );

    assert_eq!(
        cache.positions_open_count(None, None, None, None, None),
        1,
        "Open position count should be 1"
    );

    assert_eq!(
        cache.positions_closed_count(None, None, None, None, None),
        0,
        "Closed position count should be 0"
    );
}

#[rstest]
fn test_handle_order_fill_event_skips_duplicate_fill(mut execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();
    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(CashAccount::default().into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .quantity(Quantity::from(100_000))
        .build();
    let client_order_id = order.client_order_id();
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let submitted = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&submitted);

    let fill = OrderEventAny::Filled(OrderFilled::new(
        order.trader_id(),
        order.strategy_id(),
        instrument.id(),
        order.client_order_id(),
        VenueOrderId::from("V-001"),
        AccountId::test_default(),
        TradeId::new("E-19700101-000000-001-001-1"),
        order.order_side(),
        order.order_type(),
        Quantity::from(50_000),
        Price::from_str("1.0").unwrap(),
        instrument.quote_currency(),
        LiquiditySide::Maker,
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false,
        None,
        Some(Money::from("2 USD")),
    ));

    execution_engine.process(&fill);
    let (event_count, filled_qty, trade_ids, position_count) = {
        let cache = execution_engine.cache().borrow();
        let order = cache.order(&client_order_id).unwrap();
        (
            order.event_count(),
            order.filled_qty(),
            order.trade_ids().len(),
            cache.positions_total_count(None, None, None, None, None),
        )
    };

    execution_engine.process(&fill);
    let cache = execution_engine.cache().borrow();
    let order = cache.order(&client_order_id).unwrap();

    assert_eq!(order.status(), OrderStatus::PartiallyFilled);
    assert_eq!(order.filled_qty(), filled_qty);
    assert_eq!(order.event_count(), event_count);
    assert_eq!(order.trade_ids().len(), trade_ids);
    assert_eq!(
        cache.positions_total_count(None, None, None, None, None),
        position_count
    );
}

#[rstest]
fn test_handle_multiple_partial_fill_events(mut execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let order_submitted_event = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&order_submitted_event);

    let order_accepted_event = TestOrderEventStubs::accepted(
        &order,
        AccountId::test_default(),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order_accepted_event);

    let expected_position_id = PositionId::from(format!("{}-{}", instrument.id, strategy_id));

    let position = Position::new(
        &instrument.clone().into(),
        OrderFilled::new(
            order.trader_id(),
            order.strategy_id(),
            instrument.id(),
            order.client_order_id(),
            VenueOrderId::from("V-001"),
            AccountId::test_default(),
            TradeId::new("E-19700101-000000-001-001-0"), // Different trade ID
            order.order_side(),
            order.order_type(),
            order.quantity(),
            Price::from_str("1.0").unwrap(),
            instrument.quote_currency(),
            LiquiditySide::Maker,
            UUID4::new(),
            UnixNanos::default(),
            UnixNanos::default(),
            false,
            Some(expected_position_id),
            Some(Money::from("2 USD")),
        ),
    );

    execution_engine
        .cache()
        .borrow_mut()
        .add_position(&position, OmsType::Netting)
        .unwrap();
    // First partial fill: 20,100
    let fill_event_1 = OrderEventAny::Filled(OrderFilled::new(
        order.trader_id(),
        order.strategy_id(),
        instrument.id(),
        order.client_order_id(),
        VenueOrderId::from("V-001"),
        AccountId::test_default(),
        TradeId::new("E-19700101-000000-001-001-1"),
        order.order_side(),
        order.order_type(),
        Quantity::from(20_100), // First partial fill
        Price::from_str("1.0").unwrap(),
        instrument.quote_currency(),
        LiquiditySide::Maker,
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false, // reconciliation
        None,  // No position_id
        Some(Money::from("2 USD")),
    ));
    execution_engine.process(&fill_event_1);

    // Second partial fill: 19,900
    let fill_event_2 = OrderEventAny::Filled(OrderFilled::new(
        order.trader_id(),
        order.strategy_id(),
        instrument.id(),
        order.client_order_id(),
        VenueOrderId::from("V-001"),
        AccountId::test_default(),
        TradeId::new("E-19700101-000000-001-001-2"),
        order.order_side(),
        order.order_type(),
        Quantity::from(19_900), // Second partial fill
        Price::from_str("1.0").unwrap(),
        instrument.quote_currency(),
        LiquiditySide::Maker,
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false, // reconciliation
        None,  // No position_id
        Some(Money::from("2 USD")),
    ));
    execution_engine.process(&fill_event_2);

    // Third partial fill: 60,000 (completes the order)
    let fill_event_3 = OrderEventAny::Filled(OrderFilled::new(
        order.trader_id(),
        order.strategy_id(),
        instrument.id(),
        order.client_order_id(),
        VenueOrderId::from("V-001"),
        AccountId::test_default(),
        TradeId::new("E-19700101-000000-001-001-3"),
        order.order_side(),
        order.order_type(),
        Quantity::from(60_000), // Third partial fill (completes 100,000)
        Price::from_str("1.0").unwrap(),
        instrument.quote_currency(),
        LiquiditySide::Maker,
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false, // reconciliation
        None,  // No position_id
        Some(Money::from("2 USD")),
    ));
    execution_engine.process(&fill_event_3);
    let cache = execution_engine.cache().borrow();

    assert!(
        cache.position_exists(&expected_position_id),
        "Position should exist with generated ID"
    );

    assert!(
        cache.is_position_open(&expected_position_id),
        "Position should be open"
    );

    assert!(
        !cache.is_position_closed(&expected_position_id),
        "Position should not be closed"
    );

    let position = cache
        .position(&expected_position_id)
        .expect("Position should be retrievable");

    assert_eq!(
        position.id, expected_position_id,
        "Position should have correct ID"
    );

    assert!(
        cache
            .position_ids(None, None, None, None)
            .contains(&expected_position_id),
        "Position ID should be in position IDs list"
    );

    assert!(
        !cache
            .position_closed_ids(
                Some(&Venue::test_default()),
                Some(&instrument.id),
                Some(&strategy_id),
                None
            )
            .contains(&expected_position_id),
        "Position should not be in closed IDs for strategy"
    );

    assert!(
        !cache
            .position_closed_ids(None, None, None, None)
            .contains(&expected_position_id),
        "Position should not be in closed IDs"
    );

    assert!(
        cache
            .position_open_ids(
                Some(&Venue::test_default()),
                Some(&instrument.id),
                Some(&strategy_id),
                None
            )
            .contains(&expected_position_id),
        "Position should be in open IDs for strategy"
    );

    assert!(
        cache
            .position_open_ids(None, None, None, None)
            .contains(&expected_position_id),
        "Position should be in open IDs"
    );

    assert_eq!(
        cache.positions_total_count(None, None, None, None, None),
        1,
        "Total position count should be 1"
    );

    assert_eq!(
        cache.positions_open_count(None, None, None, None, None),
        1,
        "Open position count should be 1"
    );

    assert_eq!(
        cache.positions_closed_count(None, None, None, None, None),
        0,
        "Closed position count should be 0"
    );
}

#[rstest]
fn test_handle_position_opening_with_position_id_none(mut execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let order_submitted_event = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&order_submitted_event);

    let order_accepted_event = TestOrderEventStubs::accepted(
        &order,
        AccountId::test_default(),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order_accepted_event);

    let order_filled_event = TestOrderEventStubs::filled(
        &order,
        &instrument.clone().into(),
        Some(TradeId::new("E-19700101-000000-001-001")),
        None,                            // position_id = None (let engine generate it)
        None,                            // last_px
        None,                            // last_qty
        None,                            // liquidity_side
        None,                            // commission
        None,                            // ts_filled_ns
        Some(AccountId::test_default()), // account_id
    );

    execution_engine.process(&order_filled_event);
    let cache = execution_engine.cache().borrow();
    let position_ids = cache.position_ids(None, None, None, None);
    assert_eq!(position_ids.len(), 1, "Should have exactly one position");

    // Get the generated position ID
    let generated_position_id = position_ids
        .iter()
        .next()
        .expect("Should have one position ID");

    let position = cache
        .position(generated_position_id)
        .expect("Position should exist");

    assert!(position.is_open(), "Position should be open");

    assert!(!position.is_closed(), "Position should not be closed");

    assert_eq!(
        position.strategy_id, strategy_id,
        "Position should have correct strategy ID"
    );

    assert_eq!(
        position.instrument_id, instrument.id,
        "Position should have correct instrument ID"
    );

    assert!(
        cache.position_exists(generated_position_id),
        "Position should exist with generated ID"
    );

    assert!(
        cache.is_position_open(generated_position_id),
        "Position should be open"
    );

    assert!(
        !cache.is_position_closed(generated_position_id),
        "Position should not be closed"
    );

    assert!(
        cache
            .position_ids(None, None, None, None)
            .contains(generated_position_id),
        "Position ID should be in position IDs list"
    );

    assert!(
        cache
            .position_open_ids(None, None, None, None)
            .contains(generated_position_id),
        "Position should be in open IDs"
    );

    assert!(
        !cache
            .position_closed_ids(None, None, None, None)
            .contains(generated_position_id),
        "Position should not be in closed IDs"
    );

    assert_eq!(
        cache.positions_total_count(None, None, None, None, None),
        1,
        "Total position count should be 1"
    );

    assert_eq!(
        cache.positions_open_count(None, None, None, None, None),
        1,
        "Open position count should be 1"
    );

    assert_eq!(
        cache.positions_closed_count(None, None, None, None, None),
        0,
        "Closed position count should be 0"
    );
}

#[rstest]
fn test_add_to_existing_position_on_order_fill(mut execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();

    let order1 = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order1.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let order1_submitted_event = TestOrderEventStubs::submitted(&order1, AccountId::test_default());
    execution_engine.process(&order1_submitted_event);

    let order1_accepted_event = TestOrderEventStubs::accepted(
        &order1,
        AccountId::test_default(),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order1_accepted_event);

    // Fill first order to create a position
    let order1_filled_event = TestOrderEventStubs::filled(
        &order1,
        &instrument.clone().into(),
        Some(TradeId::new("E-19700101-000000-001-001-1")),
        None,                            // Let system generate position ID
        None,                            // last_px
        None,                            // last_qty
        None,                            // liquidity_side
        None,                            // commission
        None,                            // ts_filled_ns
        Some(AccountId::test_default()), // account_id
    );
    execution_engine.process(&order1_filled_event);

    // Get the created position ID
    let cache = execution_engine.cache().borrow();
    let position_ids = cache.position_ids(None, None, None, None);

    assert_eq!(
        position_ids.len(),
        1,
        "Should have exactly one position after first fill"
    );
    let expected_position_id = *position_ids.iter().next().unwrap();
    println!("Expected position ID: {expected_position_id:?}");
    drop(cache);

    let order2 = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order2.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let order2_submitted_event = TestOrderEventStubs::submitted(&order2, AccountId::test_default());
    execution_engine.process(&order2_submitted_event);

    let order2_accepted_event = TestOrderEventStubs::accepted(
        &order2,
        AccountId::test_default(),
        VenueOrderId::from("V-002"),
    );
    execution_engine.process(&order2_accepted_event);

    let order2_filled_event = TestOrderEventStubs::filled(
        &order2,
        &instrument.clone().into(),
        Some(TradeId::new("E-19700101-000000-001-001-2")),
        Some(expected_position_id),      // Specify existing position ID
        None,                            // last_px
        None,                            // last_qty
        None,                            // liquidity_side
        None,                            // commission
        None,                            // ts_filled_ns
        Some(AccountId::test_default()), // account_id
    );
    execution_engine.process(&order2_filled_event);
    let cache = execution_engine.cache().borrow();

    assert!(
        cache.position_exists(&expected_position_id),
        "Position should exist after second fill"
    );

    assert!(
        cache.is_position_open(&expected_position_id),
        "Position should be open after second fill"
    );

    assert!(
        !cache.is_position_closed(&expected_position_id),
        "Position should not be closed after second fill"
    );

    let position = cache
        .position(&expected_position_id)
        .expect("Position should be retrievable");

    assert_eq!(
        position.buy_qty,
        Quantity::from(200_000), // 100_000 + 100_000
        "Position should have combined quantity from both orders"
    );

    assert_eq!(
        position.id, expected_position_id,
        "Position should have the expected ID"
    );

    assert_eq!(
        position.strategy_id, strategy_id,
        "Position should have correct strategy ID"
    );

    assert_eq!(
        position.instrument_id, instrument.id,
        "Position should have correct instrument ID"
    );

    assert_eq!(
        cache.positions_total_count(None, None, None, None, None),
        1,
        "Total position count should be 1"
    );

    assert_eq!(
        cache.positions_open_count(None, None, None, None, None),
        1,
        "Open position count should be 1"
    );

    assert_eq!(
        cache.positions_closed_count(None, None, None, None, None),
        0,
        "Closed position count should be 0"
    );

    assert!(
        cache
            .position_open_ids(None, None, None, None)
            .contains(&expected_position_id),
        "Position should be in open IDs"
    );

    assert!(
        !cache
            .position_closed_ids(None, None, None, None)
            .contains(&expected_position_id),
        "Position should not be in closed IDs"
    );

    assert_eq!(
        cache
            .position_open_ids(
                Some(&Venue::test_default()),
                Some(&instrument.id),
                Some(&strategy_id),
                None
            )
            .len(),
        1,
        "Should have 1 open position for strategy"
    );

    assert_eq!(
        cache
            .position_closed_ids(
                Some(&Venue::test_default()),
                Some(&instrument.id),
                Some(&strategy_id),
                None
            )
            .len(),
        0,
        "Should have 0 closed positions for strategy"
    );
}

#[rstest]
fn test_close_position_on_order_fill(mut execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();

    let order1 = OrderTestBuilder::new(OrderType::StopMarket)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .trigger_price(Price::from_str("1.00000").unwrap())
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order1.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let order1_submitted_event = TestOrderEventStubs::submitted(&order1, AccountId::test_default());
    execution_engine.process(&order1_submitted_event);

    let order1_accepted_event = TestOrderEventStubs::accepted(
        &order1,
        AccountId::test_default(),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order1_accepted_event);

    // For netting OMS, position ID is determined as {instrument_id}-{strategy_id}
    let position_id = PositionId::new(format!("{}-{}", instrument.id, strategy_id));

    // Fill first order to open position
    let order1_filled_event = TestOrderEventStubs::filled(
        &order1,
        &instrument.clone().into(),
        Some(TradeId::new("E-19700101-000000-001-001-1")),
        None,
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );
    execution_engine.process(&order1_filled_event);

    {
        let cache = execution_engine.cache().borrow();
        assert!(
            cache.position_exists(&position_id),
            "Position should exist after first fill"
        );
        assert!(
            cache.is_position_open(&position_id),
            "Position should be open after first fill"
        );
        assert!(
            !cache.is_position_closed(&position_id),
            "Position should not be closed after first fill"
        );
    } // Cache borrow ends here

    let order2 = OrderTestBuilder::new(OrderType::StopMarket)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .side(OrderSide::Sell)
        .quantity(Quantity::from(100_000))
        .trigger_price(Price::from_str("1.00000").unwrap())
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order2.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let order2_submitted_event = TestOrderEventStubs::submitted(&order2, AccountId::test_default());
    execution_engine.process(&order2_submitted_event);

    let order2_accepted_event = TestOrderEventStubs::accepted(
        &order2,
        AccountId::test_default(),
        VenueOrderId::from("V-002"),
    );
    execution_engine.process(&order2_accepted_event);

    let order2_filled_event = TestOrderEventStubs::filled(
        &order2,
        &instrument.into(),
        Some(TradeId::new("E-19700101-000000-001-001-2")),
        None,
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );
    execution_engine.process(&order2_filled_event);

    {
        let cache = execution_engine.cache().borrow();

        assert!(
            cache.position_exists(&position_id),
            "Position should still exist after closing"
        );

        let position = cache.position(&position_id).expect("Position should exist");
        assert!(
            position.is_closed(),
            "Position should be closed after second fill"
        );

        assert!(
            !position.is_open(),
            "Position should not be open after second fill"
        );

        assert!(
            cache.is_position_closed(&position_id),
            "Cache should report position as closed"
        );

        assert!(
            !cache.is_position_open(&position_id),
            "Cache should not report position as open"
        );

        assert_eq!(
            cache.positions_total_count(None, None, None, None, None),
            1,
            "Total position count should be 1"
        );

        assert_eq!(
            cache.positions_open_count(None, None, None, None, None),
            0,
            "Open position count should be 0"
        );

        assert_eq!(
            cache.positions_closed_count(None, None, None, None, None),
            1,
            "Closed position count should be 1"
        );

        assert!(
            !cache
                .position_open_ids(None, None, None, None)
                .contains(&position_id),
            "Position should not be in open IDs"
        );

        assert!(
            cache
                .position_closed_ids(None, None, None, None)
                .contains(&position_id),
            "Position should be in closed IDs"
        );
    } // Cache borrow ends here
}

#[rstest]
fn test_multiple_strategy_positions_opened(mut execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy1_id = StrategyId::from("TEST-STRATEGY-001");
    let strategy2_id = StrategyId::from("TEST-STRATEGY-002");
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();

    let order1 = OrderTestBuilder::new(OrderType::StopMarket)
        .trader_id(trader_id)
        .strategy_id(strategy1_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-19700101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .trigger_price(Price::from_str("1.00000").unwrap())
        .build();

    let order2 = OrderTestBuilder::new(OrderType::StopMarket)
        .trader_id(trader_id)
        .strategy_id(strategy2_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-19700101-000000-001-002-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .trigger_price(Price::from_str("1.00000").unwrap())
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order1.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order2.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    // For netting OMS, position IDs are determined as {instrument_id}-{strategy_id}
    let position1_id = PositionId::new(format!("{}-{}", instrument.id, strategy1_id));
    let position2_id = PositionId::new(format!("{}-{}", instrument.id, strategy2_id));

    let order1_submitted_event = TestOrderEventStubs::submitted(&order1, AccountId::test_default());
    execution_engine.process(&order1_submitted_event);

    let order1_accepted_event = TestOrderEventStubs::accepted(
        &order1,
        AccountId::test_default(),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order1_accepted_event);

    let order1_filled_event = TestOrderEventStubs::filled(
        &order1,
        &instrument.clone().into(),
        Some(TradeId::new("E-19700101-000000-001-001-1")),
        None,
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );
    execution_engine.process(&order1_filled_event);

    let order2_submitted_event = TestOrderEventStubs::submitted(&order2, AccountId::test_default());
    execution_engine.process(&order2_submitted_event);

    let order2_accepted_event = TestOrderEventStubs::accepted(
        &order2,
        AccountId::test_default(),
        VenueOrderId::from("V-002"),
    );
    execution_engine.process(&order2_accepted_event);

    let order2_filled_event = TestOrderEventStubs::filled(
        &order2,
        &instrument.clone().into(),
        Some(TradeId::new("E-19700101-000000-001-001-2")),
        None,
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );
    execution_engine.process(&order2_filled_event);

    let cache = execution_engine.cache().borrow();

    assert!(
        cache.position_exists(&position1_id),
        "Position 1 should exist"
    );
    assert!(
        cache.position_exists(&position2_id),
        "Position 2 should exist"
    );

    assert!(
        cache.is_position_open(&position1_id),
        "Position 1 should be open"
    );
    assert!(
        cache.is_position_open(&position2_id),
        "Position 2 should be open"
    );

    assert!(
        !cache.is_position_closed(&position1_id),
        "Position 1 should not be closed"
    );
    assert!(
        !cache.is_position_closed(&position2_id),
        "Position 2 should not be closed"
    );

    assert!(
        cache.position(&position1_id).is_some(),
        "Position 1 should be retrievable"
    );
    assert!(
        cache.position(&position2_id).is_some(),
        "Position 2 should be retrievable"
    );

    let venue = Venue::test_default();
    assert!(
        cache
            .position_ids(
                Some(&venue),
                Some(&instrument.id),
                Some(&strategy1_id),
                None
            )
            .contains(&position1_id),
        "Position 1 should be in strategy1's position IDs"
    );
    assert!(
        cache
            .position_ids(
                Some(&venue),
                Some(&instrument.id),
                Some(&strategy2_id),
                None
            )
            .contains(&position2_id),
        "Position 2 should be in strategy2's position IDs"
    );

    assert!(
        cache
            .position_ids(None, None, None, None)
            .contains(&position1_id),
        "Position 1 should be in global position IDs"
    );
    assert!(
        cache
            .position_ids(None, None, None, None)
            .contains(&position2_id),
        "Position 2 should be in global position IDs"
    );

    assert_eq!(
        cache.position_open_ids(None, None, None, None).len(),
        2,
        "Should have 2 open positions globally"
    );

    assert_eq!(
        cache
            .position_open_ids(
                Some(&venue),
                Some(&instrument.id),
                Some(&strategy1_id),
                None
            )
            .len(),
        1,
        "Strategy1 should have 1 open position"
    );

    assert_eq!(
        cache
            .position_open_ids(
                Some(&venue),
                Some(&instrument.id),
                Some(&strategy2_id),
                None
            )
            .len(),
        1,
        "Strategy2 should have 1 open position"
    );

    assert!(
        cache
            .position_open_ids(
                Some(&venue),
                Some(&instrument.id),
                Some(&strategy1_id),
                None
            )
            .contains(&position1_id),
        "Position 1 should be in strategy1's open IDs"
    );
    assert!(
        cache
            .position_open_ids(
                Some(&venue),
                Some(&instrument.id),
                Some(&strategy2_id),
                None
            )
            .contains(&position2_id),
        "Position 2 should be in strategy2's open IDs"
    );
    assert!(
        cache
            .position_open_ids(None, None, None, None)
            .contains(&position1_id),
        "Position 1 should be in global open IDs"
    );
    assert!(
        cache
            .position_open_ids(None, None, None, None)
            .contains(&position2_id),
        "Position 2 should be in global open IDs"
    );

    assert!(
        !cache
            .position_closed_ids(
                Some(&venue),
                Some(&instrument.id),
                Some(&strategy1_id),
                None
            )
            .contains(&position1_id),
        "Position 1 should not be in strategy1's closed IDs"
    );
    assert!(
        !cache
            .position_closed_ids(
                Some(&venue),
                Some(&instrument.id),
                Some(&strategy2_id),
                None
            )
            .contains(&position2_id),
        "Position 2 should not be in strategy2's closed IDs"
    );
    assert!(
        !cache
            .position_closed_ids(None, None, None, None)
            .contains(&position1_id),
        "Position 1 should not be in global closed IDs"
    );
    assert!(
        !cache
            .position_closed_ids(None, None, None, None)
            .contains(&position2_id),
        "Position 2 should not be in global closed IDs"
    );

    assert_eq!(
        cache.positions_total_count(None, None, None, None, None),
        2,
        "Total position count should be 2"
    );

    assert_eq!(
        cache.positions_open_count(None, None, None, None, None),
        2,
        "Open position count should be 2"
    );

    assert_eq!(
        cache.positions_closed_count(None, None, None, None, None),
        0,
        "Closed position count should be 0"
    );
}

// test_multiple_strategy_positions_one_active_one_closed

#[rstest]
fn test_flip_position_on_opposite_filled_same_position_sell(mut execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Hedging,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();

    let order1 = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    let order2 = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-002-1"))
        .side(OrderSide::Sell)
        .quantity(Quantity::from(150_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order1.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order2.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let position_id = PositionId::from("P-19700101-000000-000-000-1");

    let order1_submitted_event = TestOrderEventStubs::submitted(&order1, AccountId::test_default());
    execution_engine.process(&order1_submitted_event);

    let order1_accepted_event = TestOrderEventStubs::accepted(
        &order1,
        AccountId::test_default(),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order1_accepted_event);

    let order1_filled_event = TestOrderEventStubs::filled(
        &order1,
        &instrument.clone().into(),
        Some(TradeId::new("E-19700101-000000-001-001-1")),
        Some(position_id),
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );
    execution_engine.process(&order1_filled_event);

    {
        let cache = execution_engine.cache().borrow();
        assert!(
            cache.position_exists(&position_id),
            "Initial position should exist"
        );
        assert!(
            cache.is_position_open(&position_id),
            "Initial position should be open"
        );

        let position = cache.position(&position_id).expect("Position should exist");
        assert_eq!(position.side, PositionSide::Long, "Position should be long");
        assert_eq!(
            position.quantity,
            Quantity::from(100_000),
            "Position quantity should be 100,000"
        );
    }

    let order2_submitted_event = TestOrderEventStubs::submitted(&order2, AccountId::test_default());
    execution_engine.process(&order2_submitted_event);

    let order2_accepted_event = TestOrderEventStubs::accepted(
        &order2,
        AccountId::test_default(),
        VenueOrderId::from("V-002"),
    );
    execution_engine.process(&order2_accepted_event);

    let order2_filled_event = TestOrderEventStubs::filled(
        &order2,
        &instrument.clone().into(),
        Some(TradeId::new("E-19700101-000000-001-001-2")),
        Some(position_id), // Fill against the same position
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );
    execution_engine.process(&order2_filled_event);

    let cache = execution_engine.cache().borrow();

    // In Rust Netting OMS, position flipping behavior is different from Python
    // Let's check what actually happened:
    let all_position_ids = cache.position_ids(None, None, None, None);
    println!("All position IDs after flip: {all_position_ids:?}");

    // There should be at least one position (possibly 2 if a new flipped position was created)
    assert!(
        !all_position_ids.is_empty(),
        "Should have at least one position after flip"
    );

    if cache.position_exists(&position_id) {
        let original_position = cache
            .position(&position_id)
            .expect("Original position should exist");
        println!(
            "Original position after flip: is_closed={}, quantity={:?}, side={:?}",
            original_position.is_closed(),
            original_position.quantity,
            original_position.side
        );

        // The original position should be closed after flipping
        assert!(
            original_position.is_closed(),
            "Original position should be closed after flip"
        );
    }

    // Look for a flipped position (either with 'F' suffix or just another position)
    let open_positions = cache.position_open_ids(None, None, None, None);
    println!("Open position IDs after flip: {open_positions:?}");

    if open_positions.is_empty() {
        // If no open positions, the flip might have resulted in a flat position
        // This could happen if the implementation is different
        panic!(
            "Expected to find at least one open position after flip, but found none. All positions: {all_position_ids:?}"
        );
    } else {
        // Find the open position (should be the flipped one)
        let flipped_position_id = open_positions
            .iter()
            .next()
            .expect("Should have at least one open position");
        let flipped_position = cache
            .position(flipped_position_id)
            .expect("Flipped position should exist");

        println!(
            "Flipped position: id={:?}, side={:?}, quantity={:?}",
            flipped_position_id, flipped_position.side, flipped_position.quantity
        );

        assert_eq!(
            flipped_position.side,
            PositionSide::Short,
            "Flipped position should be short"
        );

        assert_eq!(
            flipped_position.quantity,
            Quantity::from(50_000), // 150,000 - 100,000 = 50,000
            "Flipped position quantity should be 50,000 (150,000 - 100,000)"
        );

        assert_eq!(
            flipped_position.strategy_id, strategy_id,
            "Flipped position should have same strategy ID"
        );

        assert_eq!(
            flipped_position.instrument_id, instrument.id,
            "Flipped position should have same instrument ID"
        );

        assert_eq!(
            cache.positions_open_count(None, None, None, None, None),
            1,
            "Should have 1 open position (flipped position)"
        );

        assert_eq!(
            cache.positions_closed_count(None, None, None, None, None),
            1,
            "Should have 1 closed position (original position)"
        );

        assert_eq!(
            cache.positions_total_count(None, None, None, None, None),
            2,
            "Total position count should be 2 (original + flipped)"
        );
    }
}

#[rstest]
fn test_flip_position_on_opposite_filled_same_position_buy(mut execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Hedging,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();

    let order1 = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Sell)
        .quantity(Quantity::from(100_000))
        .build();

    let order2 = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-002-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(150_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order1.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order2.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let position_id = PositionId::from("P-19700101-000000-000-None-1");

    let order1_submitted_event = TestOrderEventStubs::submitted(&order1, AccountId::test_default());
    execution_engine.process(&order1_submitted_event);

    let order1_accepted_event = TestOrderEventStubs::accepted(
        &order1,
        AccountId::test_default(),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order1_accepted_event);

    let order1_filled_event = TestOrderEventStubs::filled(
        &order1,
        &instrument.clone().into(),
        Some(TradeId::new("E-19700101-000000-001-001-1")),
        Some(position_id),
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );
    execution_engine.process(&order1_filled_event);

    {
        let cache = execution_engine.cache().borrow();
        assert!(
            cache.position_exists(&position_id),
            "Initial position should exist"
        );
        assert!(
            cache.is_position_open(&position_id),
            "Initial position should be open"
        );

        let position = cache.position(&position_id).expect("Position should exist");
        assert_eq!(
            position.side,
            PositionSide::Short,
            "Position should be short"
        );
        assert_eq!(
            position.quantity,
            Quantity::from(100_000),
            "Position quantity should be 100,000"
        );
    }

    let order2_submitted_event = TestOrderEventStubs::submitted(&order2, AccountId::test_default());
    execution_engine.process(&order2_submitted_event);

    let order2_accepted_event = TestOrderEventStubs::accepted(
        &order2,
        AccountId::test_default(),
        VenueOrderId::from("V-002"),
    );
    execution_engine.process(&order2_accepted_event);

    let order2_filled_event = TestOrderEventStubs::filled(
        &order2,
        &instrument.clone().into(),
        Some(TradeId::new("E-19700101-000000-001-001-2")),
        Some(position_id), // Fill against the same position
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );
    execution_engine.process(&order2_filled_event);

    let cache = execution_engine.cache().borrow();

    // Get all position IDs to see what was created
    let all_position_ids = cache.position_ids(None, None, None, None);
    println!("All position IDs after flip: {all_position_ids:?}");

    // There should be at least one position (possibly 2 if a new flipped position was created)
    assert!(
        !all_position_ids.is_empty(),
        "Should have at least one position after flip"
    );

    if cache.position_exists(&position_id) {
        let original_position = cache
            .position(&position_id)
            .expect("Original position should exist");
        println!(
            "Original position after flip: is_closed={}, quantity={:?}, side={:?}",
            original_position.is_closed(),
            original_position.quantity,
            original_position.side
        );

        // The original position should be closed after flipping
        assert!(
            original_position.is_closed(),
            "Original position should be closed after flip"
        );
    }

    // Look for a flipped position (either with 'F' suffix or just another position)
    let open_positions = cache.position_open_ids(None, None, None, None);
    println!("Open position IDs after flip: {open_positions:?}");

    if open_positions.is_empty() {
        // If no open positions, the flip might have resulted in a flat position
        // This could happen if the implementation is different
        panic!(
            "Expected to find at least one open position after flip, but found none. All positions: {all_position_ids:?}"
        );
    } else {
        // Find the open position (should be the flipped one)
        let flipped_position_id = open_positions
            .iter()
            .next()
            .expect("Should have at least one open position");
        let flipped_position = cache
            .position(flipped_position_id)
            .expect("Flipped position should exist");

        println!(
            "Flipped position: id={:?}, side={:?}, quantity={:?}",
            flipped_position_id, flipped_position.side, flipped_position.quantity
        );

        assert_eq!(
            flipped_position.side,
            PositionSide::Long,
            "Flipped position should be long"
        );

        assert_eq!(
            flipped_position.quantity,
            Quantity::from(50_000), // 150,000 - 100,000 = 50,000
            "Flipped position quantity should be 50,000 (150,000 - 100,000)"
        );

        assert_eq!(
            flipped_position.strategy_id, strategy_id,
            "Flipped position should have same strategy ID"
        );

        assert_eq!(
            flipped_position.instrument_id, instrument.id,
            "Flipped position should have same instrument ID"
        );

        assert_eq!(
            cache.positions_open_count(None, None, None, None, None),
            1,
            "Should have 1 open position (flipped position)"
        );

        assert_eq!(
            cache.positions_closed_count(None, None, None, None, None),
            1,
            "Should have 1 closed position (original position)"
        );

        assert_eq!(
            cache.positions_total_count(None, None, None, None, None),
            2,
            "Total position count should be 2 (original + flipped)"
        );
    }
}

#[rstest]
fn test_flip_position_on_flat_position_then_filled_reusing_position_id(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Hedging,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();

    let order1 = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Sell)
        .quantity(Quantity::from(100_000))
        .build();

    let order2 = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-002-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    let order3 = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-003-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order1.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order2.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order3.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let position_id = PositionId::from("P-19700101-000000-000-001-1");

    let order1_submitted_event = TestOrderEventStubs::submitted(&order1, AccountId::test_default());
    execution_engine.process(&order1_submitted_event);

    let order1_accepted_event = TestOrderEventStubs::accepted(
        &order1,
        AccountId::test_default(),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order1_accepted_event);

    let order1_filled_event = TestOrderEventStubs::filled(
        &order1,
        &instrument.clone().into(),
        Some(TradeId::new("E-19700101-000000-001-001-1")),
        Some(position_id),
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );
    execution_engine.process(&order1_filled_event);

    {
        let cache = execution_engine.cache().borrow();
        assert!(
            cache.position_exists(&position_id),
            "Initial position should exist"
        );
        assert!(
            cache.is_position_open(&position_id),
            "Initial position should be open"
        );

        let position = cache.position(&position_id).expect("Position should exist");
        assert_eq!(
            position.side,
            PositionSide::Short,
            "Position should be short"
        );
        assert_eq!(
            position.quantity,
            Quantity::from(100_000),
            "Position quantity should be 100,000"
        );
    }

    let order2_submitted_event = TestOrderEventStubs::submitted(&order2, AccountId::test_default());
    execution_engine.process(&order2_submitted_event);

    let order2_accepted_event = TestOrderEventStubs::accepted(
        &order2,
        AccountId::test_default(),
        VenueOrderId::from("V-002"),
    );
    execution_engine.process(&order2_accepted_event);

    let order2_filled_event = TestOrderEventStubs::filled(
        &order2,
        &instrument.into(),
        Some(TradeId::new("E-19700101-000000-001-001-2")),
        Some(position_id), // Fill against the same position
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );
    execution_engine.process(&order2_filled_event);

    {
        let cache = execution_engine.cache().borrow();
        let position = cache.position(&position_id).expect("Position should exist");
        assert!(position.is_closed(), "Position should be closed (flat)");
        assert_eq!(
            position.signed_qty, 0.0,
            "Position signed quantity should be 0"
        );
    }

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(
            order3.clone(),
            Some(position_id),
            Some(ClientId::from("STUB")),
            true,
        )
        .unwrap();

    // because it's trying to use a closed position ID
    {
        let cache = execution_engine.cache().borrow();
        let cached_order3 = cache
            .order(&order3.client_order_id())
            .expect("Order 3 should be in cache");

        assert_eq!(
            cached_order3.status(),
            OrderStatus::Initialized,
            "Order 3 should remain initialized when using closed position ID"
        );
    }
}

#[rstest]
fn test_cached_position_id_used_for_netting_fill(mut execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    // Add order WITH a user-supplied position_id in the cache
    let user_position_id = PositionId::from("MY-CUSTOM-POS-1");
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(
            order.clone(),
            Some(user_position_id),
            Some(ClientId::from("STUB")),
            true,
        )
        .unwrap();

    let order_submitted_event = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&order_submitted_event);

    let order_accepted_event = TestOrderEventStubs::accepted(
        &order,
        AccountId::test_default(),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order_accepted_event);

    let netting_position_id = PositionId::new(format!("{}-{}", instrument.id, strategy_id));

    // Fill with position_id = None; engine should use cached value
    let order_filled_event = TestOrderEventStubs::filled(
        &order,
        &instrument.into(),
        Some(TradeId::new("E-19700101-000000-001-001-1")),
        None,
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );
    execution_engine.process(&order_filled_event);

    let cache = execution_engine.cache().borrow();

    // The cached user-supplied position_id must be used, NOT the netting-generated one
    assert!(
        cache.position_exists(&user_position_id),
        "Position should exist with user-supplied ID"
    );
    assert!(
        cache.is_position_open(&user_position_id),
        "Position should be open"
    );

    assert!(
        !cache.position_exists(&netting_position_id),
        "No position should exist with the netting-generated ID"
    );

    assert_eq!(
        cache.positions_total_count(None, None, None, None, None),
        1,
        "Total position count should be 1"
    );
}

#[rstest]
fn test_cached_position_id_used_for_hedging_fill(mut execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Hedging,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    // Add order WITH a user-supplied position_id in the cache
    let user_position_id = PositionId::from("MY-HEDGE-POS-1");
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(
            order.clone(),
            Some(user_position_id),
            Some(ClientId::from("STUB")),
            true,
        )
        .unwrap();

    let order_submitted_event = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&order_submitted_event);

    let order_accepted_event = TestOrderEventStubs::accepted(
        &order,
        AccountId::test_default(),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order_accepted_event);

    // Fill with position_id = None; engine should use cached value
    let order_filled_event = TestOrderEventStubs::filled(
        &order,
        &instrument.into(),
        Some(TradeId::new("E-19700101-000000-001-001-1")),
        None,
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );
    execution_engine.process(&order_filled_event);

    let cache = execution_engine.cache().borrow();

    assert!(
        cache.position_exists(&user_position_id),
        "Position should exist with user-supplied ID"
    );
    assert!(
        cache.is_position_open(&user_position_id),
        "Position should be open"
    );

    let position = cache
        .position(&user_position_id)
        .expect("Position should exist");
    assert_eq!(position.side, PositionSide::Long, "Position should be long");
    assert_eq!(
        position.quantity,
        Quantity::from(100_000),
        "Position quantity should be 100,000"
    );
}

#[rstest]
fn test_cached_position_id_overrides_fill_position_id(mut execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Hedging,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    // Cache order with user-supplied position_id
    let cached_position_id = PositionId::from("CACHED-POS");
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(
            order.clone(),
            Some(cached_position_id),
            Some(ClientId::from("STUB")),
            true,
        )
        .unwrap();

    let order_submitted_event = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&order_submitted_event);

    let order_accepted_event = TestOrderEventStubs::accepted(
        &order,
        AccountId::test_default(),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order_accepted_event);

    // Fill with a DIFFERENT position_id (venue-supplied); cached should take precedence
    let venue_position_id = PositionId::from("VENUE-POS");
    let order_filled_event = TestOrderEventStubs::filled(
        &order,
        &instrument.into(),
        Some(TradeId::new("E-19700101-000000-001-001-1")),
        Some(venue_position_id),
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );
    execution_engine.process(&order_filled_event);

    let cache = execution_engine.cache().borrow();

    // Cached position_id takes precedence over venue-supplied
    assert!(
        cache.position_exists(&cached_position_id),
        "Position should exist with cached ID"
    );
    assert!(
        !cache.position_exists(&venue_position_id),
        "No position should exist with venue-supplied ID"
    );
    assert!(
        cache.is_position_open(&cached_position_id),
        "Position should be open"
    );
}

#[rstest]
fn test_exec_algorithm_position_id_propagates_to_primary_order(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Hedging,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();

    let exec_algo_id = ExecAlgorithmId::new("TWAP");
    let primary_client_order_id = ClientOrderId::from("O-PRIMARY-001");
    let child_client_order_id = ClientOrderId::from("O-CHILD-001");

    // Primary order (the exec spawn parent)
    let primary_order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(primary_client_order_id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(200_000))
        .exec_algorithm_id(exec_algo_id)
        .exec_spawn_id(primary_client_order_id)
        .build();

    // Child order (spawned by the exec algorithm, references primary via exec_spawn_id)
    let child_order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(child_client_order_id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .exec_algorithm_id(exec_algo_id)
        .exec_spawn_id(primary_client_order_id)
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(primary_order, None, Some(ClientId::from("STUB")), true)
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(
            child_order.clone(),
            None,
            Some(ClientId::from("STUB")),
            true,
        )
        .unwrap();

    let child_submitted_event =
        TestOrderEventStubs::submitted(&child_order, AccountId::test_default());
    execution_engine.process(&child_submitted_event);

    let child_accepted_event = TestOrderEventStubs::accepted(
        &child_order,
        AccountId::test_default(),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&child_accepted_event);

    // Fill the child order with no position_id; engine should generate one and propagate
    let child_filled_event = TestOrderEventStubs::filled(
        &child_order,
        &instrument.into(),
        Some(TradeId::new("E-19700101-000000-001-001-1")),
        None,
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );
    execution_engine.process(&child_filled_event);

    let cache = execution_engine.cache().borrow();

    let primary = cache
        .order(&primary_client_order_id)
        .expect("Primary order should be in cache");
    assert!(
        primary.position_id().is_some(),
        "Primary order should have position_id assigned"
    );

    let primary_cached_pos_id = cache.position_id(&primary_client_order_id);
    assert!(
        primary_cached_pos_id.is_some(),
        "Cache should index position_id for primary order"
    );

    assert_eq!(
        primary.position_id().unwrap(),
        *primary_cached_pos_id.unwrap(),
        "Primary order position_id and cache index should match"
    );

    let position_id = primary.position_id().unwrap();
    assert!(
        cache.position_exists(&position_id),
        "Position should exist with generated ID"
    );
    assert!(
        cache.is_position_open(&position_id),
        "Position should be open"
    );
}

#[rstest]
fn test_exec_algorithm_does_not_overwrite_primary_cached_position_id(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Hedging,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();

    let exec_algo_id = ExecAlgorithmId::new("TWAP");
    let primary_client_order_id = ClientOrderId::from("O-PRIMARY-002");
    let child_client_order_id = ClientOrderId::from("O-CHILD-002");
    let user_position_id = PositionId::from("USER-ALGO-POS");

    let primary_order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(primary_client_order_id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(200_000))
        .exec_algorithm_id(exec_algo_id)
        .exec_spawn_id(primary_client_order_id)
        .build();

    let child_order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(child_client_order_id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .exec_algorithm_id(exec_algo_id)
        .exec_spawn_id(primary_client_order_id)
        .build();

    // Primary order submitted WITH a user-supplied position_id
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(
            primary_order,
            Some(user_position_id),
            Some(ClientId::from("STUB")),
            true,
        )
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(
            child_order.clone(),
            None,
            Some(ClientId::from("STUB")),
            true,
        )
        .unwrap();

    let child_submitted_event =
        TestOrderEventStubs::submitted(&child_order, AccountId::test_default());
    execution_engine.process(&child_submitted_event);

    let child_accepted_event = TestOrderEventStubs::accepted(
        &child_order,
        AccountId::test_default(),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&child_accepted_event);

    let child_filled_event = TestOrderEventStubs::filled(
        &child_order,
        &instrument.into(),
        Some(TradeId::new("E-19700101-000000-001-001-1")),
        None,
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );
    execution_engine.process(&child_filled_event);

    let cache = execution_engine.cache().borrow();

    // The primary order's cached position_id must NOT be overwritten
    let primary_cached_pos_id = cache
        .position_id(&primary_client_order_id)
        .expect("Primary should have cached position_id");
    assert_eq!(
        *primary_cached_pos_id, user_position_id,
        "Primary order's cached position_id should remain the user-supplied value"
    );
}

#[rstest]
fn test_flip_position_when_netting_oms(mut execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();

    let order1 = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Sell)
        .quantity(Quantity::from(100_000))
        .build();

    let order2 = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-002-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(200_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order1.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order2.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    // For netting OMS, position ID is determined as {instrument_id}-{strategy_id}
    let position_id = PositionId::new(format!("{}-{}", instrument.id, strategy_id));

    let order1_submitted_event = TestOrderEventStubs::submitted(&order1, AccountId::test_default());
    execution_engine.process(&order1_submitted_event);

    let order1_accepted_event = TestOrderEventStubs::accepted(
        &order1,
        AccountId::test_default(),
        VenueOrderId::from("V-001"),
    );
    execution_engine.process(&order1_accepted_event);

    let order1_filled_event = TestOrderEventStubs::filled(
        &order1,
        &instrument.clone().into(),
        Some(TradeId::new("E-19700101-000000-001-001-1")),
        None,
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );
    execution_engine.process(&order1_filled_event);

    {
        let cache = execution_engine.cache().borrow();
        assert!(
            cache.position_exists(&position_id),
            "Initial position should exist"
        );
        assert!(
            cache.is_position_open(&position_id),
            "Initial position should be open"
        );

        let position = cache.position(&position_id).expect("Position should exist");
        assert_eq!(
            position.side,
            PositionSide::Short,
            "Position should be short"
        );
        assert_eq!(
            position.quantity,
            Quantity::from(100_000),
            "Position quantity should be 100,000"
        );
    }

    let order2_submitted_event = TestOrderEventStubs::submitted(&order2, AccountId::test_default());
    execution_engine.process(&order2_submitted_event);

    let order2_accepted_event = TestOrderEventStubs::accepted(
        &order2,
        AccountId::test_default(),
        VenueOrderId::from("V-002"),
    );
    execution_engine.process(&order2_accepted_event);

    let order2_filled_event = TestOrderEventStubs::filled(
        &order2,
        &instrument.into(),
        Some(TradeId::new("E-19700101-000000-001-001-2")),
        None,
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    );
    execution_engine.process(&order2_filled_event);

    let cache = execution_engine.cache().borrow();

    let position = cache
        .position(&position_id)
        .expect("flipped position should exist");
    assert_eq!(
        position.id, position_id,
        "flipped position should have correct ID"
    );
    assert_eq!(
        position.quantity,
        Quantity::from(100_000),
        "flipped position should have quantity 100,000 after flip"
    );
    assert_eq!(
        position.side,
        PositionSide::Long,
        "flipped position should be long"
    );
}

//CAN CHECK THIS TEST
#[rstest]
fn test_handle_updated_order_event(mut execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let account_id = AccountId::test_default();
    let instrument = audusd_sim();

    let order = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(10_000))
        .price(Price::from_str("10.0").unwrap())
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let order_submitted_event = TestOrderEventStubs::submitted(&order, account_id);
    execution_engine.process(&order_submitted_event);

    let order_accepted_event =
        TestOrderEventStubs::accepted(&order, account_id, VenueOrderId::from("V-001"));
    execution_engine.process(&order_accepted_event);

    let order_pending_update_event = OrderEventAny::PendingUpdate(OrderPendingUpdate::new(
        trader_id,
        strategy_id,
        instrument.id,
        order.client_order_id(),
        account_id,
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false,
        Some(VenueOrderId::from("V-001")),
    ));
    execution_engine.process(&order_pending_update_event);

    // Get order from cache and check venue_order_id
    {
        let cache = execution_engine.cache().borrow();
        let cached_order = cache
            .order(&order.client_order_id())
            .expect("Order should exist in cache");
        assert_eq!(
            cached_order.venue_order_id(),
            Some(VenueOrderId::from("V-001")),
            "Order should have correct venue_order_id"
        );
    }

    let new_venue_id = VenueOrderId::from("1");
    let order_updated_event = OrderEventAny::Updated(OrderUpdated::new(
        trader_id,
        strategy_id,
        instrument.id,
        order.client_order_id(),
        order.quantity(),
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false,
        Some(new_venue_id),
        Some(account_id),
        order.price(),
        None,  // trigger_price
        None,  // protection_price
        false, // is_quote_quantity
    ));
    execution_engine.process(&order_updated_event);

    let cache = execution_engine.cache().borrow();
    let cached_order = cache
        .order(&order.client_order_id())
        .expect("Order should exist in cache");
    assert_eq!(
        cached_order.venue_order_id(),
        Some(new_venue_id),
        "Order should update venue_order_id from the OrderUpdated event"
    );
}

#[rstest]
fn test_submit_market_should_not_add_to_own_book() {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        debug: true,
        snapshot_orders: true,
        snapshot_positions: true,
        manage_own_order_books: true, // Enable own order book management
        ..Default::default()
    };

    let mut execution_engine = ExecutionEngine::new(clock, cache, Some(config));

    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let account_id = AccountId::test_default();
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        account_id,
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();
    let submit_order = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order.client_order_id(),
        order_init: order.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    execution_engine.execute(TradingCommand::SubmitOrder(submit_order));

    let cache = execution_engine.cache().borrow();
    let own_order_book = cache.own_order_book(&order.instrument_id());

    assert!(
        own_order_book.is_none(),
        "Market orders should not be added to own order book even when order book management is enabled"
    );
}

#[rstest]
#[case(TimeInForce::Fok)]
#[case(TimeInForce::Ioc)]
fn test_submit_ioc_fok_should_not_add_to_own_book(#[case] time_in_force: TimeInForce) {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        debug: true,
        snapshot_orders: true,
        snapshot_positions: true,
        manage_own_order_books: true, // Enable own order book management
        ..Default::default()
    };

    let mut execution_engine = ExecutionEngine::new(clock, cache, Some(config));

    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let account_id = AccountId::test_default();
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        account_id,
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("10.0").unwrap())
        .time_in_force(time_in_force)
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();
    let submit_order = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order.client_order_id(),
        order_init: order.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    execution_engine.execute(TradingCommand::SubmitOrder(submit_order));

    let cache = execution_engine.cache().borrow();
    let own_order_book = cache.own_order_book(&order.instrument_id());

    assert!(
        own_order_book.is_none(),
        "Orders with {time_in_force} time in force should not be added to own order book even when order book management is enabled"
    );
}

#[rstest]
fn test_submit_order_adds_to_own_book_bid() {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        debug: true,
        snapshot_orders: true,
        snapshot_positions: true,
        manage_own_order_books: true, // Enable own order book management
        ..Default::default()
    };

    let mut execution_engine = ExecutionEngine::new(clock, cache, Some(config));

    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let account_id = AccountId::test_default();
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        account_id,
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("10.0").unwrap())
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();
    let submit_order = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order.client_order_id(),
        order_init: order.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    execution_engine.execute(TradingCommand::SubmitOrder(submit_order));

    let cache = execution_engine.cache().borrow();
    let own_book = cache
        .own_order_book(&order.instrument_id())
        .expect("Own order book should exist");

    assert_eq!(
        own_book.update_count, 1,
        "Own order book should have update count of 1"
    );

    let asks = own_book.asks_as_map(None, None, None);
    assert_eq!(asks.len(), 0, "Own order book should have no ask orders");

    let bids = own_book.bids_as_map(None, None, None);
    assert_eq!(
        bids.len(),
        1,
        "Own order book should have exactly one bid price level"
    );

    let price_key = dec!(10.0);
    assert!(
        bids.contains_key(&price_key),
        "Own order book should contain bid orders at price 10.0"
    );

    let bid_orders = &bids[&price_key];
    assert_eq!(
        bid_orders.len(),
        1,
        "Should have exactly one order at price level 10.0"
    );

    let own_order = &bid_orders[0];
    assert_eq!(
        own_order.client_order_id,
        order.client_order_id(),
        "Own order should have the same client order ID"
    );
    assert_eq!(
        own_order.price.as_decimal(),
        dec!(10.0),
        "Own order should have price 10.0"
    );
    assert_eq!(
        own_order.size.as_decimal(),
        Decimal::from(100_000),
        "Own order should have size 100,000"
    );
    assert_eq!(
        own_order.status,
        OrderStatus::Initialized,
        "Own order should have status Initialized"
    );

    assert!(
        own_book.is_order_in_book(&order.client_order_id()),
        "Order should be in the own order book"
    );

    let bid_client_order_ids = own_book.bid_client_order_ids();
    assert_eq!(
        bid_client_order_ids.len(),
        1,
        "Should have exactly one bid client order ID"
    );
    assert_eq!(
        bid_client_order_ids[0],
        order.client_order_id(),
        "Bid client order ID should match the submitted order"
    );

    let ask_client_order_ids = own_book.ask_client_order_ids();
    assert_eq!(
        ask_client_order_ids.len(),
        0,
        "Should have no ask client order IDs"
    );
}

#[rstest]
fn test_submit_order_adds_to_own_book_ask() {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        debug: true,
        snapshot_orders: true,
        snapshot_positions: true,
        manage_own_order_books: true, // Enable own order book management
        ..Default::default()
    };

    let mut execution_engine = ExecutionEngine::new(clock, cache, Some(config));

    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let account_id = AccountId::test_default();
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        account_id,
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Sell)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("11.0").unwrap())
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();
    let submit_order = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order.client_order_id(),
        order_init: order.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    execution_engine.execute(TradingCommand::SubmitOrder(submit_order));

    let cache = execution_engine.cache().borrow();
    let own_book = cache
        .own_order_book(&order.instrument_id())
        .expect("Own order book should exist");

    assert_eq!(
        own_book.update_count, 1,
        "Own order book should have update count of 1"
    );

    let bids = own_book.bids_as_map(None, None, None);
    assert_eq!(bids.len(), 0, "Own order book should have no bid orders");

    let asks = own_book.asks_as_map(None, None, None);
    assert_eq!(
        asks.len(),
        1,
        "Own order book should have exactly one ask price level"
    );

    let price_key = dec!(11.0);
    assert!(
        asks.contains_key(&price_key),
        "Own order book should contain ask orders at price 11.0"
    );

    let ask_orders = &asks[&price_key];
    assert_eq!(
        ask_orders.len(),
        1,
        "Should have exactly one order at price level 11.0"
    );

    let own_order = &ask_orders[0];
    assert_eq!(
        own_order.client_order_id,
        order.client_order_id(),
        "Own order should have the same client order ID"
    );
    assert_eq!(
        own_order.price.as_decimal(),
        dec!(11.0),
        "Own order should have price 11.0"
    );
    assert_eq!(
        own_order.size.as_decimal(),
        Decimal::from(100_000),
        "Own order should have size 100,000"
    );
    assert_eq!(
        own_order.status,
        OrderStatus::Initialized,
        "Own order should have status Initialized"
    );

    assert!(
        own_book.is_order_in_book(&order.client_order_id()),
        "Order should be in the own order book"
    );

    let ask_client_order_ids = own_book.ask_client_order_ids();
    assert_eq!(
        ask_client_order_ids.len(),
        1,
        "Should have exactly one ask client order ID"
    );
    assert_eq!(
        ask_client_order_ids[0],
        order.client_order_id(),
        "Ask client order ID should match the submitted order"
    );

    let bid_client_order_ids = own_book.bid_client_order_ids();
    assert_eq!(
        bid_client_order_ids.len(),
        0,
        "Should have no bid client order IDs"
    );
}

#[rstest]
fn test_cancel_order_removes_from_own_book() {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        debug: true,
        snapshot_orders: true,
        snapshot_positions: true,
        manage_own_order_books: true, // Enable own order book management
        ..Default::default()
    };

    let mut execution_engine = ExecutionEngine::new(clock, cache, Some(config));

    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let account_id = AccountId::test_default();
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        account_id,
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let order_bid = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("10.0").unwrap())
        .build();

    let order_ask = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-2"))
        .side(OrderSide::Sell)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("11.0").unwrap())
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order_bid.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order_ask.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();
    let submit_order_bid = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order_bid.client_order_id(),
        order_init: order_bid.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    let submit_order_ask = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order_ask.client_order_id(),
        order_init: order_ask.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    // Submit orders to create own order books
    execution_engine.execute(TradingCommand::SubmitOrder(submit_order_bid));
    execution_engine.execute(TradingCommand::SubmitOrder(submit_order_ask));
    let order_submitted_bid = TestOrderEventStubs::submitted(&order_bid, account_id);
    let order_submitted_ask = TestOrderEventStubs::submitted(&order_ask, account_id);
    execution_engine.process(&order_submitted_bid);
    execution_engine.process(&order_submitted_ask);

    let order_accepted_bid =
        TestOrderEventStubs::accepted(&order_bid, account_id, VenueOrderId::from("V-001"));
    let order_accepted_ask =
        TestOrderEventStubs::accepted(&order_ask, account_id, VenueOrderId::from("V-002"));
    execution_engine.process(&order_accepted_bid);
    execution_engine.process(&order_accepted_ask);

    let cancel_order_bid = CancelOrder {
        trader_id,
        client_id: Some(ClientId::from("STUB")),
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order_bid.client_order_id(),
        venue_order_id: Some(VenueOrderId::from("V-001")),
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
        params: None,
    };

    let cancel_order_ask = CancelOrder {
        trader_id,
        client_id: Some(ClientId::from("STUB")),
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order_ask.client_order_id(),
        venue_order_id: Some(VenueOrderId::from("V-002")),
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
        params: None,
    };

    execution_engine.execute(TradingCommand::CancelOrder(cancel_order_bid));
    execution_engine.execute(TradingCommand::CancelOrder(cancel_order_ask));

    let order_canceled_bid =
        TestOrderEventStubs::canceled(&order_bid, account_id, Some(VenueOrderId::from("V-001")));
    let order_canceled_ask =
        TestOrderEventStubs::canceled(&order_ask, account_id, Some(VenueOrderId::from("V-002")));
    execution_engine.process(&order_canceled_bid);
    execution_engine.process(&order_canceled_ask);

    let cache = execution_engine.cache().borrow();
    let own_book = cache
        .own_order_book(&instrument.id)
        .expect("Own order book should exist");

    assert_eq!(own_book.update_count, 8, "Expected update count to be 8");

    let bid_client_order_ids = own_book.bid_client_order_ids();
    let ask_client_order_ids = own_book.ask_client_order_ids();

    assert!(bid_client_order_ids.is_empty(), "Expected no bid orders");
    assert!(ask_client_order_ids.is_empty(), "Expected no ask orders");

    let bids = own_book.bids_as_map(None, None, None);
    let asks = own_book.asks_as_map(None, None, None);

    assert!(bids.is_empty(), "Expected no bid orders in own book");
    assert!(asks.is_empty(), "Expected no ask orders in own book");
}

#[rstest]
fn test_own_book_status_filtering() {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        debug: true,
        snapshot_orders: true,
        snapshot_positions: true,
        manage_own_order_books: true, // Enable own order book management
        ..Default::default()
    };

    let mut execution_engine = ExecutionEngine::new(clock, cache, Some(config));

    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let account_id = AccountId::test_default();
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        account_id,
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let order_bid = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("10.0").unwrap())
        .build();

    let order_ask = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-2"))
        .side(OrderSide::Sell)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("11.0").unwrap())
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order_bid.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order_ask.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();
    let submit_order_bid = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order_bid.client_order_id(),
        order_init: order_bid.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    let submit_order_ask = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order_ask.client_order_id(),
        order_init: order_ask.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    // Submit orders to create own order books
    execution_engine.execute(TradingCommand::SubmitOrder(submit_order_bid));
    execution_engine.execute(TradingCommand::SubmitOrder(submit_order_ask));
    let order_submitted_bid = TestOrderEventStubs::submitted(&order_bid, account_id);
    let order_submitted_ask = TestOrderEventStubs::submitted(&order_ask, account_id);
    execution_engine.process(&order_submitted_bid);
    execution_engine.process(&order_submitted_ask);

    let order_accepted_bid =
        TestOrderEventStubs::accepted(&order_bid, account_id, VenueOrderId::from("V-001"));
    let order_accepted_ask =
        TestOrderEventStubs::accepted(&order_ask, account_id, VenueOrderId::from("V-002"));
    execution_engine.process(&order_accepted_bid);
    execution_engine.process(&order_accepted_ask);

    let cancel_order_bid = CancelOrder {
        trader_id,
        client_id: Some(ClientId::from("STUB")),
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order_bid.client_order_id(),
        venue_order_id: Some(VenueOrderId::from("V-001")),
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
        params: None,
    };

    let cancel_order_ask = CancelOrder {
        trader_id,
        client_id: Some(ClientId::from("STUB")),
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order_ask.client_order_id(),
        venue_order_id: Some(VenueOrderId::from("V-002")),
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
        params: None,
    };

    execution_engine.execute(TradingCommand::CancelOrder(cancel_order_bid));
    execution_engine.execute(TradingCommand::CancelOrder(cancel_order_ask));

    let order_canceled_bid =
        TestOrderEventStubs::canceled(&order_bid, account_id, Some(VenueOrderId::from("V-001")));
    let order_canceled_ask =
        TestOrderEventStubs::canceled(&order_ask, account_id, Some(VenueOrderId::from("V-002")));
    execution_engine.process(&order_canceled_bid);
    execution_engine.process(&order_canceled_ask);

    let cache = execution_engine.cache().borrow();

    // First check that the orders in the cache have been updated to Canceled status
    let bid_order = cache
        .order(&order_bid.client_order_id())
        .expect("Bid order should exist in cache");
    let ask_order = cache
        .order(&order_ask.client_order_id())
        .expect("Ask order should exist in cache");

    assert_eq!(
        bid_order.status(),
        OrderStatus::Canceled,
        "Bid order should be in Canceled status"
    );
    assert_eq!(
        ask_order.status(),
        OrderStatus::Canceled,
        "Ask order should be in Canceled status"
    );

    let own_book = cache
        .own_order_book(&instrument.id)
        .expect("Own order book should exist");

    assert_eq!(own_book.update_count, 8, "Expected update count to be 8");
    let bids = own_book.bids_as_map(None, None, None);
    let asks = own_book.asks_as_map(None, None, None);

    assert_eq!(
        bids.len(),
        0,
        "Expected 0 bid orders in own book after cancellation"
    );
    assert_eq!(
        asks.len(),
        0,
        "Expected 0 ask orders in own book after cancellation"
    );

    // Since orders are removed from the own book when canceled,
    // filtering by any status should return empty results
    let accepted_statuses: AHashSet<OrderStatus> =
        AHashSet::from_iter([OrderStatus::Accepted, OrderStatus::PartiallyFilled]);

    let filtered_bids = own_book.bids_as_map(Some(&accepted_statuses), None, None);
    let filtered_asks = own_book.asks_as_map(Some(&accepted_statuses), None, None);

    assert!(
        filtered_bids.is_empty(),
        "Expected no bid orders after cancellation"
    );
    assert!(
        filtered_asks.is_empty(),
        "Expected no ask orders after cancellation"
    );
}

#[rstest]
fn test_filled_order_removes_from_own_book() {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        debug: true,
        snapshot_orders: true,
        snapshot_positions: true,
        manage_own_order_books: true, // Enable own order book management
        ..Default::default()
    };

    let mut execution_engine = ExecutionEngine::new(clock, cache, Some(config));

    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let account_id = AccountId::test_default();
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        account_id,
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let order_bid = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("10.0").unwrap())
        .build();

    let order_ask = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-2"))
        .side(OrderSide::Sell)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("11.0").unwrap())
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order_bid.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order_ask.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();
    let submit_order_bid = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order_bid.client_order_id(),
        order_init: order_bid.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    let submit_order_ask = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order_ask.client_order_id(),
        order_init: order_ask.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    // Submit orders to create own order books
    execution_engine.execute(TradingCommand::SubmitOrder(submit_order_bid));
    execution_engine.execute(TradingCommand::SubmitOrder(submit_order_ask));
    let order_submitted_bid = TestOrderEventStubs::submitted(&order_bid, account_id);
    let order_submitted_ask = TestOrderEventStubs::submitted(&order_ask, account_id);
    execution_engine.process(&order_submitted_bid);
    execution_engine.process(&order_submitted_ask);

    let order_accepted_bid =
        TestOrderEventStubs::accepted(&order_bid, account_id, VenueOrderId::from("V-001"));
    let order_accepted_ask =
        TestOrderEventStubs::accepted(&order_ask, account_id, VenueOrderId::from("V-002"));
    execution_engine.process(&order_accepted_bid);
    execution_engine.process(&order_accepted_ask);
    let order_filled_bid = OrderEventAny::Filled(OrderFilled::new(
        order_bid.trader_id(),
        order_bid.strategy_id(),
        instrument.id(),
        order_bid.client_order_id(),
        VenueOrderId::from("V-001"), // Use the same venue_order_id as the accepted event
        account_id,
        TradeId::new("E-19700101-000000-001-001"),
        order_bid.order_side(),
        order_bid.order_type(),
        order_bid.quantity(), // last_qty: set to full order quantity to ensure Filled status
        Price::from_str("10.0").unwrap(), // last_px
        instrument.quote_currency(),
        LiquiditySide::Maker,
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false, // reconciliation
        None,  // position_id
        None,  // commission
    ));
    let order_filled_ask = OrderEventAny::Filled(OrderFilled::new(
        order_ask.trader_id(),
        order_ask.strategy_id(),
        instrument.id(),
        order_ask.client_order_id(),
        VenueOrderId::from("V-002"), // Use the same venue_order_id as the accepted event
        account_id,
        TradeId::new("E-19700101-000000-001-002"),
        order_ask.order_side(),
        order_ask.order_type(),
        order_ask.quantity(), // last_qty: set to full order quantity to ensure Filled status
        Price::from_str("11.0").unwrap(), // last_px
        instrument.quote_currency(),
        LiquiditySide::Maker,
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false, // reconciliation
        None,  // position_id
        None,  // commission
    ));
    execution_engine.process(&order_filled_bid);
    execution_engine.process(&order_filled_ask);

    let cache = execution_engine.cache().borrow();

    let bid_order = cache
        .order(&order_bid.client_order_id())
        .expect("Bid order should exist in cache");
    let ask_order = cache
        .order(&order_ask.client_order_id())
        .expect("Ask order should exist in cache");

    assert_eq!(
        bid_order.status(),
        OrderStatus::Filled,
        "Bid order should be in Filled status"
    );
    assert_eq!(
        ask_order.status(),
        OrderStatus::Filled,
        "Ask order should be in Filled status"
    );

    let own_book = cache
        .own_order_book(&instrument.id)
        .expect("Own order book should exist");

    assert_eq!(own_book.update_count, 8, "Expected update count to be 8");
    let bids = own_book.bids_as_map(None, None, None);
    let asks = own_book.asks_as_map(None, None, None);

    assert_eq!(
        bids.len(),
        0,
        "Expected 0 bid orders in own book after fill"
    );
    assert_eq!(
        asks.len(),
        0,
        "Expected 0 ask orders in own book after fill"
    );

    let bids = own_book.bids_as_map(None, None, None);
    let asks = own_book.asks_as_map(None, None, None);

    assert!(bids.is_empty(), "Expected no bid orders after fill");
    assert!(asks.is_empty(), "Expected no ask orders after fill");
}

#[rstest]
fn test_order_updates_in_own_book() {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        debug: true,
        snapshot_orders: true,
        snapshot_positions: true,
        manage_own_order_books: true, // Enable own order book management
        ..Default::default()
    };

    let mut execution_engine = ExecutionEngine::new(clock, cache, Some(config));

    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let account_id = AccountId::test_default();
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        account_id,
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let order_bid = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("10.0").unwrap())
        .build();

    let order_ask = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-2"))
        .side(OrderSide::Sell)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("11.0").unwrap())
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order_bid.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order_ask.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();
    let submit_order_bid = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order_bid.client_order_id(),
        order_init: order_bid.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    let submit_order_ask = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order_ask.client_order_id(),
        order_init: order_ask.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    // Submit orders to create own order books
    execution_engine.execute(TradingCommand::SubmitOrder(submit_order_bid));
    execution_engine.execute(TradingCommand::SubmitOrder(submit_order_ask));
    let order_submitted_bid = TestOrderEventStubs::submitted(&order_bid, account_id);
    let order_submitted_ask = TestOrderEventStubs::submitted(&order_ask, account_id);
    execution_engine.process(&order_submitted_bid);
    execution_engine.process(&order_submitted_ask);

    let order_accepted_bid =
        TestOrderEventStubs::accepted(&order_bid, account_id, VenueOrderId::from("V-001"));
    let order_accepted_ask =
        TestOrderEventStubs::accepted(&order_ask, account_id, VenueOrderId::from("V-002"));
    execution_engine.process(&order_accepted_bid);
    execution_engine.process(&order_accepted_ask);

    let new_bid_price = Price::from_str("9.0").unwrap();
    let new_ask_price = Price::from_str("12.0").unwrap();

    let order_updated_bid = OrderEventAny::Updated(OrderUpdated::new(
        order_bid.trader_id(),
        order_bid.strategy_id(),
        instrument.id(),
        order_bid.client_order_id(),
        order_bid.quantity(),
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false,                             // reconciliation
        Some(VenueOrderId::from("V-001")), // venue_order_id
        Some(account_id),                  // account_id
        Some(new_bid_price),               // new price
        None,                              // trigger_price
        None,                              // protection_price
        false,                             // is_quote_quantity
    ));

    let order_updated_ask = OrderEventAny::Updated(OrderUpdated::new(
        order_ask.trader_id(),
        order_ask.strategy_id(),
        instrument.id(),
        order_ask.client_order_id(),
        order_ask.quantity(),
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false,                             // reconciliation
        Some(VenueOrderId::from("V-002")), // venue_order_id
        Some(account_id),                  // account_id
        Some(new_ask_price),               // new price
        None,                              // trigger_price
        None,                              // protection_price
        false,                             // is_quote_quantity
    ));

    execution_engine.process(&order_updated_bid);
    execution_engine.process(&order_updated_ask);

    let cache = execution_engine.cache().borrow();
    let own_book = cache
        .own_order_book(&instrument.id)
        .expect("Own order book should exist");

    assert_eq!(own_book.update_count, 8, "Expected update count to be 8");
    let bids = own_book.bids_as_map(None, None, None);
    let asks = own_book.asks_as_map(None, None, None);

    assert_eq!(bids.len(), 1, "Expected 1 bid order in own book");
    assert_eq!(asks.len(), 1, "Expected 1 ask order in own book");

    let bid_orders = bids
        .get(&new_bid_price.as_decimal())
        .expect("Should have bid orders at new price");
    assert_eq!(
        bid_orders.len(),
        1,
        "Should have exactly 1 bid order at new price"
    );
    let own_order_bid = &bid_orders[0];
    assert_eq!(own_order_bid.client_order_id, order_bid.client_order_id());
    assert_eq!(own_order_bid.price, new_bid_price);
    assert_eq!(own_order_bid.status, OrderStatus::Accepted);

    let ask_orders = asks
        .get(&new_ask_price.as_decimal())
        .expect("Should have ask orders at new price");
    assert_eq!(
        ask_orders.len(),
        1,
        "Should have exactly 1 ask order at new price"
    );
    let own_order_ask = &ask_orders[0];
    assert_eq!(own_order_ask.client_order_id, order_ask.client_order_id());
    assert_eq!(own_order_ask.price, new_ask_price);
    assert_eq!(own_order_ask.status, OrderStatus::Accepted);
    let accepted_statuses: AHashSet<OrderStatus> = AHashSet::from_iter([OrderStatus::Accepted]);

    let filtered_bids = own_book.bids_as_map(Some(&accepted_statuses), None, None);
    let filtered_asks = own_book.asks_as_map(Some(&accepted_statuses), None, None);

    assert_eq!(
        filtered_bids.len(),
        1,
        "Should have 1 bid order with ACCEPTED status"
    );
    assert_eq!(
        filtered_asks.len(),
        1,
        "Should have 1 ask order with ACCEPTED status"
    );

    let filtered_bid_orders = filtered_bids
        .get(&new_bid_price.as_decimal())
        .expect("Should have filtered bid orders");
    let filtered_ask_orders = filtered_asks
        .get(&new_ask_price.as_decimal())
        .expect("Should have filtered ask orders");

    assert_eq!(
        filtered_bid_orders.len(),
        1,
        "Should have exactly 1 filtered bid order"
    );
    assert_eq!(
        filtered_ask_orders.len(),
        1,
        "Should have exactly 1 filtered ask order"
    );

    assert_eq!(
        filtered_bid_orders[0].client_order_id,
        order_bid.client_order_id()
    );
    assert_eq!(
        filtered_ask_orders[0].client_order_id,
        order_ask.client_order_id()
    );
}

#[rstest]
fn test_position_flip_with_own_order_book() {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        debug: true,
        snapshot_orders: true,
        snapshot_positions: true,
        manage_own_order_books: true, // Enable own order book management
        ..Default::default()
    };

    let mut execution_engine = ExecutionEngine::new(clock, cache, Some(config));

    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let account_id = AccountId::test_default();
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let account = CashAccount::default();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(account.into())
        .unwrap();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        account_id,
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let buy_order = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("1.0").unwrap())
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(buy_order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();
    let submit_buy_order = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: buy_order.client_order_id(),
        order_init: buy_order.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    // Submit buy order to create own order book
    execution_engine.execute(TradingCommand::SubmitOrder(submit_buy_order));

    let order_submitted_buy = TestOrderEventStubs::submitted(&buy_order, account_id);
    let order_accepted_buy =
        TestOrderEventStubs::accepted(&buy_order, account_id, VenueOrderId::from("V-001"));
    execution_engine.process(&order_submitted_buy);
    execution_engine.process(&order_accepted_buy);

    let order_filled_buy = OrderEventAny::Filled(OrderFilled::new(
        buy_order.trader_id(),
        buy_order.strategy_id(),
        instrument.id(),
        buy_order.client_order_id(),
        VenueOrderId::from("V-001"),
        account_id,
        TradeId::new("E-19700101-000000-001-001"),
        buy_order.order_side(),
        buy_order.order_type(),
        buy_order.quantity(), // last_qty: set to full order quantity to ensure Filled status
        Price::from_str("1.0").unwrap(), // last_px
        instrument.quote_currency(),
        LiquiditySide::Maker,
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false, // reconciliation
        None,  // position_id
        None,  // commission
    ));
    execution_engine.process(&order_filled_buy);

    // The position ID should be generated by the execution engine
    // Let's find the position that was created
    let position_id = {
        let cache = execution_engine.cache().borrow();
        let positions = cache.positions(None, None, None, None, None);
        assert_eq!(
            positions.len(),
            1,
            "Should have exactly 1 position after buy order fill"
        );

        let original_position = &positions[0];

        assert!(
            original_position.is_open(),
            "Original position should be open"
        );
        assert_eq!(
            original_position.side,
            PositionSide::Long,
            "Original position should be long"
        );
        assert_eq!(
            original_position.quantity,
            Quantity::from(100_000),
            "Original position should have correct quantity"
        );

        original_position.id
    };

    let sell_order = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-2"))
        .side(OrderSide::Sell)
        .quantity(Quantity::from(200_000)) // Twice the size to flip position
        .price(Price::from_str("1.1").unwrap())
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(sell_order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();
    let submit_sell_order = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: sell_order.client_order_id(),
        order_init: sell_order.init_event().clone(),
        position_id: Some(position_id),
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    execution_engine.execute(TradingCommand::SubmitOrder(submit_sell_order));

    let order_submitted_sell = TestOrderEventStubs::submitted(&sell_order, account_id);
    let order_accepted_sell =
        TestOrderEventStubs::accepted(&sell_order, account_id, VenueOrderId::from("V-002"));
    execution_engine.process(&order_submitted_sell);
    execution_engine.process(&order_accepted_sell);

    let order_filled_sell = OrderEventAny::Filled(OrderFilled::new(
        sell_order.trader_id(),
        sell_order.strategy_id(),
        instrument.id(),
        sell_order.client_order_id(),
        VenueOrderId::from("V-002"),
        account_id,
        TradeId::new("E-19700101-000000-001-002"),
        sell_order.order_side(),
        sell_order.order_type(),
        sell_order.quantity(), // last_qty: set to full order quantity to ensure Filled status
        Price::from_str("1.1").unwrap(), // last_px
        instrument.quote_currency(),
        LiquiditySide::Maker,
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        false,             // reconciliation
        Some(position_id), // position_id
        None,              // commission
    ));
    execution_engine.process(&order_filled_sell);

    let cache = execution_engine.cache().borrow();

    let positions = cache.positions(None, None, None, None, None);
    assert_eq!(
        positions.len(),
        1,
        "Expected 1 position after position flip (position replacement)"
    );

    // Get the flipped position
    let flipped_position = &positions[0];

    assert!(
        flipped_position.is_open(),
        "Flipped position should be open"
    );
    assert_eq!(
        flipped_position.side,
        PositionSide::Short,
        "Flipped position should be short"
    );
    assert_eq!(
        flipped_position.quantity,
        Quantity::from(100_000),
        "Flipped position should have correct quantity"
    );

    // The position ID remains the same but the side and quantity have changed
    assert_eq!(
        flipped_position.id, position_id,
        "Position ID should remain the same after flip"
    );

    let own_book = cache
        .own_order_book(&instrument.id)
        .expect("Own order book should exist");
    assert!(
        own_book.update_count > 0,
        "Own order book should have been updated"
    );

    // Orders should be removed from own book after fill
    let bids = own_book.bids_as_map(None, None, None);
    let asks = own_book.asks_as_map(None, None, None);

    assert_eq!(
        bids.len(),
        0,
        "Expected 0 bid orders in own book after fill"
    );
    assert_eq!(asks.len(), 0, "Expected 0 ask orders after fill");
}

#[rstest]
fn test_own_book_with_crossed_orders() {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        debug: true,
        snapshot_orders: true,
        snapshot_positions: true,
        manage_own_order_books: true, // Enable own order book management
        ..Default::default()
    };

    let mut execution_engine = ExecutionEngine::new(clock, cache, Some(config));

    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let account_id = AccountId::test_default();
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        account_id,
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let buy_order = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("1.05").unwrap()) // Buy at 1.05
        .build();

    let sell_order = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-2"))
        .side(OrderSide::Sell)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("1.04").unwrap()) // Sell at 1.04 (below the bid)
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(buy_order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(sell_order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();
    let submit_buy_order = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: buy_order.client_order_id(),
        order_init: buy_order.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    let submit_sell_order = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: sell_order.client_order_id(),
        order_init: sell_order.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    // Submit orders to create own order books
    execution_engine.execute(TradingCommand::SubmitOrder(submit_buy_order));
    execution_engine.execute(TradingCommand::SubmitOrder(submit_sell_order));
    let order_submitted_buy = TestOrderEventStubs::submitted(&buy_order, account_id);
    let order_submitted_sell = TestOrderEventStubs::submitted(&sell_order, account_id);
    execution_engine.process(&order_submitted_buy);
    execution_engine.process(&order_submitted_sell);

    let order_accepted_buy =
        TestOrderEventStubs::accepted(&buy_order, account_id, VenueOrderId::from("V-001"));
    let order_accepted_sell =
        TestOrderEventStubs::accepted(&sell_order, account_id, VenueOrderId::from("V-002"));
    execution_engine.process(&order_accepted_buy);
    execution_engine.process(&order_accepted_sell);

    let cache = execution_engine.cache().borrow();
    let own_book = cache
        .own_order_book(&instrument.id)
        .expect("Own order book should exist");

    assert!(
        own_book.update_count > 0,
        "Expected update count to be greater than 0"
    );

    let bids = own_book.bids_as_map(None, None, None);
    let asks = own_book.asks_as_map(None, None, None);

    assert_eq!(bids.len(), 1, "Expected 1 bid order in own book");
    assert_eq!(asks.len(), 1, "Expected 1 ask order in own book");

    let bid_price = dec!(1.05);
    let ask_price = dec!(1.04);

    assert!(
        bids.contains_key(&bid_price),
        "Expected bid order at price 1.05"
    );
    assert!(
        asks.contains_key(&ask_price),
        "Expected ask order at price 1.04"
    );

    // The own book doesn't enforce market integrity rules like not allowing crossed books
    // because it's just tracking the orders, not matching them
    let accepted_statuses: AHashSet<OrderStatus> = AHashSet::from_iter([OrderStatus::Accepted]);

    let active_bid_orders = own_book.bids_as_map(Some(&accepted_statuses), None, None);
    let active_ask_orders = own_book.asks_as_map(Some(&accepted_statuses), None, None);

    assert_eq!(active_bid_orders.len(), 1, "Expected 1 active bid order");
    assert!(
        active_bid_orders.contains_key(&bid_price),
        "Expected active bid order at price 1.05"
    );

    assert_eq!(active_ask_orders.len(), 1, "Expected 1 active ask order");
    assert!(
        active_ask_orders.contains_key(&ask_price),
        "Expected active ask order at price 1.04"
    );
}

#[rstest]
fn test_own_book_with_contingent_orders() {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        debug: false,
        snapshot_orders: false,
        snapshot_positions: false,
        manage_own_order_books: true, // Enable own order book management
        ..Default::default()
    };

    let mut execution_engine = ExecutionEngine::new(clock, cache, Some(config));

    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let account_id = AccountId::test_default();
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        account_id,
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let entry_order = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("1.00").unwrap()) // Limit entry price
        .build();

    let tp_order = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-002-1"))
        .side(OrderSide::Sell)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("1.10").unwrap()) // Take profit at 1.10
        .build();

    let sl_order = OrderTestBuilder::new(OrderType::StopMarket)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-003-1"))
        .side(OrderSide::Sell)
        .quantity(Quantity::from(100_000))
        .trigger_price(Price::from_str("0.90").unwrap()) // Stop loss trigger at 0.90
        .build();
    let submit_entry_order = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: entry_order.client_order_id(),
        order_init: entry_order.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    let submit_tp_order = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: tp_order.client_order_id(),
        order_init: tp_order.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    let submit_sl_order = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: sl_order.client_order_id(),
        order_init: sl_order.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(
            entry_order.clone(),
            None,
            Some(ClientId::from("STUB")),
            true,
        )
        .unwrap();
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(tp_order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(sl_order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    execution_engine.execute(TradingCommand::SubmitOrder(submit_entry_order));

    // Submit TP order (in a real bracket, this would be contingent but for testing we submit it)
    execution_engine.execute(TradingCommand::SubmitOrder(submit_tp_order));

    let entry_submitted_event = TestOrderEventStubs::submitted(&entry_order, account_id);
    execution_engine.process(&entry_submitted_event);

    let entry_accepted_event =
        TestOrderEventStubs::accepted(&entry_order, account_id, VenueOrderId::from("1"));
    execution_engine.process(&entry_accepted_event);

    let tp_submitted_event = TestOrderEventStubs::submitted(&tp_order, account_id);
    execution_engine.process(&tp_submitted_event);

    let tp_accepted_event =
        TestOrderEventStubs::accepted(&tp_order, account_id, VenueOrderId::from("2"));
    execution_engine.process(&tp_accepted_event);

    let cache = execution_engine.cache().borrow();
    let own_book = cache
        .own_order_book(&instrument.id)
        .expect("Own order book should exist");
    assert!(
        own_book.update_count > 1,
        "Own order book should have been updated"
    );

    // Entry order should be in the book as a bid
    let bids = own_book.bids_as_map(None, None, None);
    assert_eq!(bids.len(), 1, "Expected 1 bid order in own book");
    let bid_price = dec!(1.00);
    assert!(bids.contains_key(&bid_price), "Expected bid at price 1.00");
    assert_eq!(
        bids[&bid_price].len(),
        1,
        "Expected 1 order at bid price 1.00"
    );

    // TP order should be in the book as an ask (submitted)
    let asks = own_book.asks_as_map(None, None, None);
    assert_eq!(asks.len(), 1, "Expected 1 ask order in own book");
    let ask_price = dec!(1.10);
    assert!(asks.contains_key(&ask_price), "Expected ask at price 1.10");
    assert_eq!(
        asks[&ask_price].len(),
        1,
        "Expected 1 order at ask price 1.10"
    );

    drop(cache); // Release the borrow before processing more events

    // Now fill the entry order - get the updated order from cache to ensure venue_order_id is set
    let cached_entry_order = {
        let cache = execution_engine.cache().borrow();
        cache
            .order(&entry_order.client_order_id())
            .expect("Entry order should exist in cache")
            .clone()
    };

    let entry_filled_event = TestOrderEventStubs::filled(
        &cached_entry_order,
        &InstrumentAny::CurrencyPair(instrument.clone()),
        None, // trade_id
        None, // position_id
        None, // last_px
        None, // last_qty
        None, // liquidity_side
        None, // commission
        None, // ts_filled_ns
        None, // account_id
    );
    execution_engine.process(&entry_filled_event);

    // Submit and process SL order after entry is filled
    execution_engine.execute(TradingCommand::SubmitOrder(submit_sl_order));

    let sl_submitted_event = TestOrderEventStubs::submitted(&sl_order, account_id);
    execution_engine.process(&sl_submitted_event);

    let sl_accepted_event =
        TestOrderEventStubs::accepted(&sl_order, account_id, VenueOrderId::from("3"));
    execution_engine.process(&sl_accepted_event);

    let cache = execution_engine.cache().borrow();
    let own_book = cache
        .own_order_book(&instrument.id)
        .expect("Own order book should exist");

    // Entry order should be removed from the book as it's filled
    let bids = own_book.bids_as_map(None, None, None);
    assert_eq!(
        bids.len(),
        0,
        "Expected 0 bid orders in own book after entry fill"
    );

    // TP should still be in the book
    let asks = own_book.asks_as_map(None, None, None);
    assert_eq!(asks.len(), 1, "Expected 1 ask order in own book");
    let tp_price = dec!(1.10);
    assert!(
        asks.contains_key(&tp_price),
        "Expected TP order at price 1.10"
    );

    // Test that contingent orders are linked to the same position
    // Note: In this test setup, position IDs may not be automatically created
    // The main purpose is to test own order book functionality
    let entry_position_id = cache.position_id(&entry_order.client_order_id());
    let tp_position_id = cache.position_id(&tp_order.client_order_id());
    let sl_position_id = cache.position_id(&sl_order.client_order_id());

    // If position IDs exist, they should be the same for all orders in the bracket
    if let (Some(entry_pos_id), Some(tp_pos_id), Some(sl_pos_id)) =
        (entry_position_id, tp_position_id, sl_position_id)
    {
        assert_eq!(
            entry_pos_id, tp_pos_id,
            "TP order should have same position ID as entry order"
        );
        assert_eq!(
            entry_pos_id, sl_pos_id,
            "SL order should have same position ID as entry order"
        );
    }

    // The key test is that own order book behaves correctly regardless of position linking
}

#[rstest]
#[case(OrderStatus::Initialized, "1.00", vec![], true)]
#[case(OrderStatus::Submitted, "1.01", vec![OrderStatus::Submitted], true)]
#[case(OrderStatus::Accepted, "1.02", vec![OrderStatus::Submitted, OrderStatus::Accepted], true)]
#[case(OrderStatus::PartiallyFilled, "1.03", vec![OrderStatus::Submitted, OrderStatus::Accepted, OrderStatus::PartiallyFilled], true)]
#[case(OrderStatus::Filled, "1.04", vec![OrderStatus::Submitted, OrderStatus::Accepted, OrderStatus::Filled], false)]
#[case(OrderStatus::Canceled, "1.05", vec![OrderStatus::Submitted, OrderStatus::Accepted, OrderStatus::Canceled], false)]
fn test_own_book_order_status_filtering_parameterized(
    #[case] final_status: OrderStatus,
    #[case] price_str: &str,
    #[case] process_steps: Vec<OrderStatus>,
    #[case] expected_in_book: bool,
) {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        debug: false,
        snapshot_orders: false,
        snapshot_positions: false,
        manage_own_order_books: true, // Enable own order book management
        ..Default::default()
    };

    let mut execution_engine = ExecutionEngine::new(clock, cache, Some(config));

    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let account_id = AccountId::test_default();
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        account_id,
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str(price_str).unwrap())
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    // Submit the order
    let submit_order = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order.client_order_id(),
        order_init: order.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };
    execution_engine.execute(TradingCommand::SubmitOrder(submit_order));

    for step in process_steps {
        match step {
            OrderStatus::Submitted => {
                let event = TestOrderEventStubs::submitted(&order, account_id);
                execution_engine.process(&event);
            }
            OrderStatus::Accepted => {
                let event =
                    TestOrderEventStubs::accepted(&order, account_id, VenueOrderId::from("1"));
                execution_engine.process(&event);
            }
            OrderStatus::PartiallyFilled => {
                // Get the updated order from cache to ensure venue_order_id is set
                let cached_order = {
                    let cache = execution_engine.cache().borrow();
                    cache
                        .order(&order.client_order_id())
                        .expect("Order should exist in cache")
                        .clone()
                };

                let event = TestOrderEventStubs::filled(
                    &cached_order,
                    &InstrumentAny::CurrencyPair(instrument.clone()),
                    None,                         // trade_id
                    None,                         // position_id
                    None,                         // last_px
                    Some(Quantity::from(50_000)), // last_qty - partial fill
                    None,                         // liquidity_side
                    None,                         // commission
                    None,                         // ts_filled_ns
                    None,                         // account_id
                );
                execution_engine.process(&event);
            }
            OrderStatus::Filled => {
                // Get the updated order from cache to ensure venue_order_id is set
                let cached_order = {
                    let cache = execution_engine.cache().borrow();
                    cache
                        .order(&order.client_order_id())
                        .expect("Order should exist in cache")
                        .clone()
                };

                let event = TestOrderEventStubs::filled(
                    &cached_order,
                    &InstrumentAny::CurrencyPair(instrument.clone()),
                    None, // trade_id
                    None, // position_id
                    None, // last_px
                    None, // last_qty - full fill
                    None, // liquidity_side
                    None, // commission
                    None, // ts_filled_ns
                    None, // account_id
                );
                execution_engine.process(&event);
            }
            OrderStatus::Canceled => {
                let event = TestOrderEventStubs::canceled(
                    &order,
                    account_id,
                    Some(VenueOrderId::from("1")),
                );
                execution_engine.process(&event);
            }
            _ => {} // Handle other statuses if needed
        }
    }

    let cache = execution_engine.cache().borrow();
    let own_book = cache
        .own_order_book(&instrument.id)
        .expect("Own order book should exist");
    let price_decimal = Decimal::from_str(price_str).unwrap();

    if expected_in_book {
        let bids = own_book.bids_as_map(None, None, None);
        assert!(!bids.is_empty(), "Expected orders in own book");
        assert!(
            bids.contains_key(&price_decimal),
            "Expected order at price {price_str}"
        );

        // Test status filtering
        let status_filter: AHashSet<OrderStatus> = AHashSet::from_iter([final_status]);
        let filtered_bids = own_book.bids_as_map(Some(&status_filter), None, None);
        assert!(
            filtered_bids.contains_key(&price_decimal),
            "Expected order at price {price_str} with status {final_status:?}"
        );
    } else {
        // If we expect the order not to be in the book, check that the price level doesn't exist
        // or that it doesn't contain our order
        let bids = own_book.bids_as_map(None, None, None);
        if bids.contains_key(&price_decimal) {
            assert_eq!(
                bids[&price_decimal].len(),
                0,
                "Expected no orders at price {} after status {}",
                price_str,
                final_status as u8
            );
        }
    }
}

#[rstest]
fn test_own_book_combined_status_filtering() {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        debug: false,
        snapshot_orders: false,
        snapshot_positions: false,
        manage_own_order_books: true, // Enable own order book management
        ..Default::default()
    };

    let mut execution_engine = ExecutionEngine::new(clock, cache, Some(config));

    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let account_id = AccountId::test_default();
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        account_id,
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let initialized_order = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("1.00").unwrap())
        .build();

    let submitted_order = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-002-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("1.01").unwrap())
        .build();

    let accepted_order = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-003-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("1.02").unwrap())
        .build();

    let partially_filled_order = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-004-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from_str("1.03").unwrap())
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(
            initialized_order.clone(),
            None,
            Some(ClientId::from("STUB")),
            true,
        )
        .unwrap();
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(
            submitted_order.clone(),
            None,
            Some(ClientId::from("STUB")),
            true,
        )
        .unwrap();
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(
            accepted_order.clone(),
            None,
            Some(ClientId::from("STUB")),
            true,
        )
        .unwrap();
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(
            partially_filled_order.clone(),
            None,
            Some(ClientId::from("STUB")),
            true,
        )
        .unwrap();

    // 1. Submit initialized_order (remains INITIALIZED)
    let submit_initialized = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: initialized_order.client_order_id(),
        order_init: initialized_order.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };
    execution_engine.execute(TradingCommand::SubmitOrder(submit_initialized));

    // 2. Submit and process submitted_order (becomes SUBMITTED)
    let submit_submitted = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: submitted_order.client_order_id(),
        order_init: submitted_order.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };
    execution_engine.execute(TradingCommand::SubmitOrder(submit_submitted));
    let submitted_event = TestOrderEventStubs::submitted(&submitted_order, account_id);
    execution_engine.process(&submitted_event);

    // 3. Submit, submit, and accept accepted_order (becomes ACCEPTED)
    let submit_accepted = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: accepted_order.client_order_id(),
        order_init: accepted_order.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };
    execution_engine.execute(TradingCommand::SubmitOrder(submit_accepted));
    let accepted_submitted_event = TestOrderEventStubs::submitted(&accepted_order, account_id);
    execution_engine.process(&accepted_submitted_event);
    let accepted_accepted_event =
        TestOrderEventStubs::accepted(&accepted_order, account_id, VenueOrderId::from("V-003"));
    execution_engine.process(&accepted_accepted_event);

    // 4. Submit, submit, accept, and partially fill partially_filled_order (becomes PARTIALLY_FILLED)
    let submit_partial = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: partially_filled_order.client_order_id(),
        order_init: partially_filled_order.init_event().clone(),
        position_id: None,
        params: None,
        client_id: Some(ClientId::from("STUB")),
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };
    execution_engine.execute(TradingCommand::SubmitOrder(submit_partial));
    let partial_submitted_event =
        TestOrderEventStubs::submitted(&partially_filled_order, account_id);
    execution_engine.process(&partial_submitted_event);
    let partial_accepted_event = TestOrderEventStubs::accepted(
        &partially_filled_order,
        account_id,
        VenueOrderId::from("V-004"),
    );
    execution_engine.process(&partial_accepted_event);

    // Get updated order from cache for partial fill
    let cached_partial_order = {
        let cache = execution_engine.cache().borrow();
        cache
            .order(&partially_filled_order.client_order_id())
            .expect("Order should exist in cache")
            .clone()
    };

    let partial_filled_event = TestOrderEventStubs::filled(
        &cached_partial_order,
        &InstrumentAny::CurrencyPair(instrument.clone()),
        None,                         // trade_id
        None,                         // position_id
        None,                         // last_px
        Some(Quantity::from(50_000)), // last_qty - partial fill
        None,                         // liquidity_side
        None,                         // commission
        None,                         // ts_filled_ns
        None,                         // account_id
    );
    execution_engine.process(&partial_filled_event);

    let cache = execution_engine.cache().borrow();
    let own_book = cache
        .own_order_book(&instrument.id)
        .expect("Own order book should exist");

    // INITIALIZED + SUBMITTED
    let early_statuses: AHashSet<OrderStatus> =
        AHashSet::from_iter([OrderStatus::Initialized, OrderStatus::Submitted]);
    let early_orders = own_book.bids_as_map(Some(&early_statuses), None, None);
    let early_order_count: usize = early_orders.values().map(std::vec::Vec::len).sum();
    assert_eq!(
        early_order_count, 2,
        "Expected 2 orders with INITIALIZED or SUBMITTED status"
    );

    let price_100 = dec!(1.00);
    let price_101 = dec!(1.01);
    assert!(
        early_orders.contains_key(&price_100),
        "Expected order at price 1.00 in early statuses"
    );
    assert!(
        early_orders.contains_key(&price_101),
        "Expected order at price 1.01 in early statuses"
    );

    // ACCEPTED + PARTIALLY_FILLED
    let active_statuses: AHashSet<OrderStatus> =
        AHashSet::from_iter([OrderStatus::Accepted, OrderStatus::PartiallyFilled]);
    let active_orders = own_book.bids_as_map(Some(&active_statuses), None, None);
    let active_order_count: usize = active_orders.values().map(std::vec::Vec::len).sum();
    assert_eq!(
        active_order_count, 2,
        "Expected 2 orders with ACCEPTED or PARTIALLY_FILLED status"
    );

    let price_102 = dec!(1.02);
    let price_103 = dec!(1.03);
    assert!(
        active_orders.contains_key(&price_102),
        "Expected order at price 1.02 in active statuses"
    );
    assert!(
        active_orders.contains_key(&price_103),
        "Expected order at price 1.03 in active statuses"
    );

    // ALL orders (no filter)
    let all_orders = own_book.bids_as_map(None, None, None);
    let all_order_count: usize = all_orders.values().map(std::vec::Vec::len).sum();
    assert_eq!(all_order_count, 4, "Expected 4 total orders in own book");

    assert!(
        all_orders.contains_key(&price_100),
        "Expected order at price 1.00 in all orders"
    );
    assert!(
        all_orders.contains_key(&price_101),
        "Expected order at price 1.01 in all orders"
    );
    assert!(
        all_orders.contains_key(&price_102),
        "Expected order at price 1.02 in all orders"
    );
    assert!(
        all_orders.contains_key(&price_103),
        "Expected order at price 1.03 in all orders"
    );
}

#[rstest]
fn test_own_book_status_integrity_during_transitions() {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        debug: false,
        snapshot_orders: false,
        snapshot_positions: false,
        manage_own_order_books: true, // Enable own order book management
        ..Default::default()
    };

    let mut execution_engine = ExecutionEngine::new(clock, cache, Some(config));

    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let account_id = AccountId::test_default();
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        account_id,
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let prices = ["1.00", "1.01", "1.02"];
    let mut orders = Vec::new();

    for (i, price) in prices.iter().enumerate() {
        let order = OrderTestBuilder::new(OrderType::Limit)
            .trader_id(trader_id)
            .strategy_id(strategy_id)
            .instrument_id(instrument.id)
            .client_order_id(ClientOrderId::from(format!(
                "O-20240101-000000-001-00{}-1",
                i + 1
            )))
            .side(OrderSide::Buy)
            .quantity(Quantity::from(100_000))
            .price(Price::from_str(price).unwrap())
            .build();

        execution_engine
            .cache()
            .borrow_mut()
            .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
            .unwrap();

        // Submit and process to ACCEPTED
        let submit_order = SubmitOrder {
            trader_id,
            strategy_id,
            instrument_id: instrument.id,
            client_order_id: order.client_order_id(),
            order_init: order.init_event().clone(),
            position_id: None,
            params: None,
            client_id: Some(ClientId::from("STUB")),
            exec_algorithm_id: None,
            command_id: UUID4::new(),
            ts_init: UnixNanos::default(),
        };
        execution_engine.execute(TradingCommand::SubmitOrder(submit_order));

        let submitted_event = TestOrderEventStubs::submitted(&order, account_id);
        execution_engine.process(&submitted_event);

        let accepted_event = TestOrderEventStubs::accepted(
            &order,
            account_id,
            VenueOrderId::from(format!("V-00{}", i + 1)),
        );
        execution_engine.process(&accepted_event);

        orders.push(order);
    }

    {
        let cache = execution_engine.cache().borrow();
        let own_book = cache
            .own_order_book(&instrument.id)
            .expect("Own order book should exist");

        let accepted_statuses: AHashSet<OrderStatus> = AHashSet::from_iter([OrderStatus::Accepted]);
        let accepted_orders = own_book.bids_as_map(Some(&accepted_statuses), None, None);
        assert_eq!(accepted_orders.len(), 3, "Expected 3 accepted orders");

        for (price, order) in prices.iter().zip(&orders) {
            let price_decimal = Decimal::from_str(price).unwrap();
            assert!(
                accepted_orders.contains_key(&price_decimal),
                "Expected order at price {price}"
            );

            let orders_at_price = &accepted_orders[&price_decimal];
            assert!(
                orders_at_price
                    .iter()
                    .any(|o| o.client_order_id == order.client_order_id()),
                "Expected order {} at price {}",
                order.client_order_id(),
                price
            );
        }
    }

    // Test case 1: Order transitions from ACCEPTED to PARTIALLY_FILLED
    // Partially fill order 1 (index 1, price 1.01)
    let cached_order_1 = {
        let cache = execution_engine.cache().borrow();
        cache
            .order(&orders[1].client_order_id())
            .expect("Order should exist in cache")
            .clone()
    };

    let partial_fill_event = TestOrderEventStubs::filled(
        &cached_order_1,
        &InstrumentAny::CurrencyPair(instrument.clone()),
        None,                         // trade_id
        Some(PositionId::new("1")),   // position_id
        None,                         // last_px
        Some(Quantity::from(50_000)), // last_qty - partial fill
        None,                         // liquidity_side
        None,                         // commission
        None,                         // ts_filled_ns
        None,                         // account_id
    );
    execution_engine.process(&partial_fill_event);
    {
        let cache = execution_engine.cache().borrow();
        let own_book = cache
            .own_order_book(&instrument.id)
            .expect("Own order book should exist");

        let partially_filled_statuses: AHashSet<OrderStatus> =
            AHashSet::from_iter([OrderStatus::PartiallyFilled]);
        let partially_filled_orders =
            own_book.bids_as_map(Some(&partially_filled_statuses), None, None);
        assert_eq!(
            partially_filled_orders.len(),
            1,
            "Expected 1 partially filled order"
        );

        let price_101 = dec!(1.01);
        assert!(
            partially_filled_orders.contains_key(&price_101),
            "Expected partially filled order at price 1.01"
        );

        let accepted_statuses: AHashSet<OrderStatus> = AHashSet::from_iter([OrderStatus::Accepted]);
        let accepted_after_partial = own_book.bids_as_map(Some(&accepted_statuses), None, None);
        assert_eq!(
            accepted_after_partial.len(),
            2,
            "Expected 2 accepted orders after partial fill"
        );
        assert!(
            !accepted_after_partial.contains_key(&price_101),
            "Order at 1.01 should not be in accepted status"
        );
    }

    // Test case 2: Order transitions from ACCEPTED to CANCELED
    // Cancel order 2 (index 2, price 1.02)
    let cancel_event =
        TestOrderEventStubs::canceled(&orders[2], account_id, Some(VenueOrderId::from("V-003")));
    execution_engine.process(&cancel_event);
    {
        let cache = execution_engine.cache().borrow();
        let own_book = cache
            .own_order_book(&instrument.id)
            .expect("Own order book should exist");

        let canceled_statuses: AHashSet<OrderStatus> = AHashSet::from_iter([OrderStatus::Canceled]);
        let canceled_orders = own_book.bids_as_map(Some(&canceled_statuses), None, None);
        assert_eq!(
            canceled_orders.len(),
            0,
            "CANCELED orders should not appear in the book"
        );

        let accepted_statuses: AHashSet<OrderStatus> = AHashSet::from_iter([OrderStatus::Accepted]);
        let accepted_after_cancel = own_book.bids_as_map(Some(&accepted_statuses), None, None);
        assert_eq!(
            accepted_after_cancel.len(),
            1,
            "Expected 1 accepted order after cancellation"
        );

        let price_102 = dec!(1.02);
        assert!(
            !accepted_after_cancel.contains_key(&price_102),
            "Canceled order should not be in accepted status"
        );
    }

    // Test case 3: Order transitions from ACCEPTED to PARTIALLY_FILLED to FILLED
    // First partial fill on order 0 (index 0, price 1.00)
    let cached_order_0 = {
        let cache = execution_engine.cache().borrow();
        cache
            .order(&orders[0].client_order_id())
            .expect("Order should exist in cache")
            .clone()
    };

    let first_partial_fill = TestOrderEventStubs::filled(
        &cached_order_0,
        &InstrumentAny::CurrencyPair(instrument.clone()),
        Some(TradeId::new("001")),    // trade_id
        None,                         // position_id
        None,                         // last_px
        Some(Quantity::from(50_000)), // last_qty - partial fill
        None,                         // liquidity_side
        None,                         // commission
        None,                         // ts_filled_ns
        None,                         // account_id
    );
    execution_engine.process(&first_partial_fill);

    {
        let cache = execution_engine.cache().borrow();
        let own_book = cache
            .own_order_book(&instrument.id)
            .expect("Own order book should exist");

        let partially_filled_statuses: AHashSet<OrderStatus> =
            AHashSet::from_iter([OrderStatus::PartiallyFilled]);
        let partially_after_first =
            own_book.bids_as_map(Some(&partially_filled_statuses), None, None);
        assert_eq!(
            partially_after_first.len(),
            2,
            "Expected 2 partially filled orders"
        );

        let price_100 = dec!(1.00);
        assert!(
            partially_after_first.contains_key(&price_100),
            "Expected partially filled order at price 1.00"
        );
    }

    // Complete fill (remaining quantity)
    let cached_order_0_updated = {
        let cache = execution_engine.cache().borrow();
        cache
            .order(&orders[0].client_order_id())
            .expect("Order should exist in cache")
            .clone()
    };

    let complete_fill = TestOrderEventStubs::filled(
        &cached_order_0_updated,
        &InstrumentAny::CurrencyPair(instrument.clone()),
        Some(TradeId::new("002")),    // trade_id
        None,                         // position_id
        None,                         // last_px
        Some(Quantity::from(50_000)), // last_qty - remaining quantity
        None,                         // liquidity_side
        None,                         // commission
        None,                         // ts_filled_ns
        None,                         // account_id
    );
    execution_engine.process(&complete_fill);

    // Final verification
    {
        let cache = execution_engine.cache().borrow();
        let own_book = cache
            .own_order_book(&instrument.id)
            .expect("Own order book should exist");

        let partially_filled_statuses: AHashSet<OrderStatus> =
            AHashSet::from_iter([OrderStatus::PartiallyFilled]);
        let partially_after_complete =
            own_book.bids_as_map(Some(&partially_filled_statuses), None, None);
        assert_eq!(
            partially_after_complete.len(),
            1,
            "Expected 1 partially filled order after complete fill"
        );

        let order_0_cached = cache
            .order(&orders[0].client_order_id())
            .expect("Order 0 should exist");
        let order_1_cached = cache
            .order(&orders[1].client_order_id())
            .expect("Order 1 should exist");
        let order_2_cached = cache
            .order(&orders[2].client_order_id())
            .expect("Order 2 should exist");

        assert_eq!(
            order_0_cached.status(),
            OrderStatus::Filled,
            "Order 0 should be FILLED"
        );
        assert_eq!(
            order_1_cached.status(),
            OrderStatus::PartiallyFilled,
            "Order 1 should be PARTIALLY_FILLED"
        );
        assert_eq!(
            order_2_cached.status(),
            OrderStatus::Canceled,
            "Order 2 should be CANCELED"
        );

        let all_orders = own_book.bids_as_map(None, None, None);
        let price_101 = dec!(1.01);
        assert!(
            all_orders.contains_key(&price_101),
            "Order at price 1.01 should exist in own book"
        );

        // FILLED orders should not appear in the own book
        let filled_statuses: AHashSet<OrderStatus> = AHashSet::from_iter([OrderStatus::Filled]);
        let filled_orders = own_book.bids_as_map(Some(&filled_statuses), None, None);
        assert_eq!(
            filled_orders.len(),
            0,
            "FILLED orders should not appear in the own book"
        );
    }

    #[rstest]
    fn test_get_external_client_ids_when_none_configured(execution_engine: ExecutionEngine) {
        let external_ids = execution_engine.get_external_client_ids();
        assert!(external_ids.is_empty());
    }

    #[rstest]
    fn test_get_external_client_ids_returns_configured_ids() {
        let clock = Rc::new(RefCell::new(TestClock::new()));
        let cache = Rc::new(RefCell::new(Cache::default()));
        let config = ExecutionEngineConfig {
            external_clients: Some(vec![
                ClientId::from("EXTERNAL-1"),
                ClientId::from("EXTERNAL-2"),
            ]),
            ..Default::default()
        };
        let engine = ExecutionEngine::new(clock, cache, Some(config));

        let external_ids = engine.get_external_client_ids();
        assert_eq!(external_ids.len(), 2);
        assert!(external_ids.contains(&ClientId::from("EXTERNAL-1")));
        assert!(external_ids.contains(&ClientId::from("EXTERNAL-2")));
    }

    #[rstest]
    fn test_get_external_order_claim_when_none_registered(execution_engine: ExecutionEngine) {
        let instrument_id = InstrumentId::from("EUR/USD.SIM");
        let claim = execution_engine.get_external_order_claim(&instrument_id);
        assert!(claim.is_none());
    }

    #[rstest]
    fn test_register_and_get_external_order_claim(mut execution_engine: ExecutionEngine) {
        let strategy_id = StrategyId::from("TEST-001");
        let instrument_id = InstrumentId::from("EUR/USD.SIM");
        let mut claims = HashSet::new();
        claims.insert(instrument_id);

        execution_engine
            .register_external_order_claims(strategy_id, &claims)
            .unwrap();

        let claim = execution_engine.get_external_order_claim(&instrument_id);
        assert_eq!(claim, Some(strategy_id));
    }

    #[rstest]
    fn test_register_external_order_claims_duplicate_fails(mut execution_engine: ExecutionEngine) {
        let strategy_id_1 = StrategyId::from("TEST-001");
        let strategy_id_2 = StrategyId::from("TEST-002");
        let instrument_id = InstrumentId::from("EUR/USD.SIM");

        let mut claims = HashSet::new();
        claims.insert(instrument_id);

        execution_engine
            .register_external_order_claims(strategy_id_1, &claims)
            .unwrap();

        let result = execution_engine.register_external_order_claims(strategy_id_2, &claims);
        assert!(result.is_err());
        assert!(
            result
                .unwrap_err()
                .to_string()
                .contains("already exists for")
        );
    }

    #[rstest]
    fn test_register_external_order_claims_is_atomic(mut execution_engine: ExecutionEngine) {
        let strategy_id_1 = StrategyId::from("TEST-001");
        let strategy_id_2 = StrategyId::from("TEST-002");
        let instrument_id_1 = InstrumentId::from("EUR/USD.SIM");
        let instrument_id_2 = InstrumentId::from("GBP/USD.SIM");
        let instrument_id_3 = InstrumentId::from("AUD/USD.SIM");

        let mut initial_claims = HashSet::new();
        initial_claims.insert(instrument_id_2);
        execution_engine
            .register_external_order_claims(strategy_id_1, &initial_claims)
            .unwrap();

        // Try to register multiple claims where one conflicts
        let mut conflicting_claims = HashSet::new();
        conflicting_claims.insert(instrument_id_1);
        conflicting_claims.insert(instrument_id_2); // Already claimed
        conflicting_claims.insert(instrument_id_3);

        let result =
            execution_engine.register_external_order_claims(strategy_id_2, &conflicting_claims);
        assert!(result.is_err());

        assert_eq!(
            execution_engine.get_external_order_claim(&instrument_id_1),
            None
        );
        assert_eq!(
            execution_engine.get_external_order_claim(&instrument_id_2),
            Some(strategy_id_1)
        );
        assert_eq!(
            execution_engine.get_external_order_claim(&instrument_id_3),
            None
        );
    }

    #[rstest]
    fn test_get_external_order_claims_instruments(mut execution_engine: ExecutionEngine) {
        let strategy_id = StrategyId::from("TEST-001");
        let instrument_id_1 = InstrumentId::from("EUR/USD.SIM");
        let instrument_id_2 = InstrumentId::from("GBP/USD.SIM");

        let mut claims = HashSet::new();
        claims.insert(instrument_id_1);
        claims.insert(instrument_id_2);

        execution_engine
            .register_external_order_claims(strategy_id, &claims)
            .unwrap();

        let instruments = execution_engine.get_external_order_claims_instruments();
        assert_eq!(instruments.len(), 2);
        assert!(instruments.contains(&instrument_id_1));
        assert!(instruments.contains(&instrument_id_2));
    }

    #[rstest]
    fn test_register_oms_type_for_strategy(mut execution_engine: ExecutionEngine) {
        let strategy_id = StrategyId::from("TEST-001");

        execution_engine.register_oms_type(strategy_id, OmsType::Hedging);
    }

    #[rstest]
    fn test_register_oms_type_allows_override(mut execution_engine: ExecutionEngine) {
        let strategy_id = StrategyId::from("TEST-001");

        execution_engine.register_oms_type(strategy_id, OmsType::Hedging);
        execution_engine.register_oms_type(strategy_id, OmsType::Netting);
    }

    #[rstest]
    fn test_get_clients_for_orders_empty_list(execution_engine: ExecutionEngine) {
        let orders: Vec<OrderAny> = vec![];
        let clients = execution_engine.get_clients_for_orders(&orders);
        assert!(clients.is_empty());
    }

    #[rstest]
    fn test_get_clients_for_orders_with_default_client(
        mut execution_engine: ExecutionEngine,
        stub_client: StubExecutionClient,
    ) {
        let client_id = stub_client.client_id();

        execution_engine.register_default_client(Box::new(stub_client));

        let instrument = InstrumentAny::CurrencyPair(audusd_sim());
        let order = OrderTestBuilder::new(OrderType::Market)
            .instrument_id(instrument.id())
            .side(OrderSide::Buy)
            .quantity(Quantity::from("100"))
            .build();

        let clients = execution_engine.get_clients_for_orders(&[order]);
        assert_eq!(clients.len(), 1);
        assert_eq!(clients[0].client_id(), client_id);
    }

    #[rstest]
    fn test_set_manage_own_order_books(mut execution_engine: ExecutionEngine) {
        assert!(!execution_engine.config().manage_own_order_books);

        execution_engine.set_manage_own_order_books(true);
        assert!(execution_engine.config().manage_own_order_books);

        execution_engine.set_manage_own_order_books(false);
        assert!(!execution_engine.config().manage_own_order_books);
    }

    #[rstest]
    fn test_netting_flip_creates_snapshot(mut execution_engine: ExecutionEngine) {
        let trader_id = TraderId::test_default();
        let strategy_id = StrategyId::test_default();
        let instrument = audusd_sim();

        let stub_client = StubExecutionClient::new(
            ClientId::from("STUB"),
            AccountId::test_default(),
            Venue::test_default(),
            OmsType::Netting,
            None,
        );
        execution_engine
            .register_client(Box::new(stub_client))
            .unwrap();

        execution_engine
            .cache()
            .borrow_mut()
            .add_instrument(instrument.clone().into())
            .unwrap();

        let account = CashAccount::default();
        execution_engine
            .cache()
            .borrow_mut()
            .add_account(account.into())
            .unwrap();

        let order1 = OrderTestBuilder::new(OrderType::Market)
            .trader_id(trader_id)
            .strategy_id(strategy_id)
            .instrument_id(instrument.id)
            .client_order_id(ClientOrderId::from("O-1"))
            .side(OrderSide::Buy)
            .quantity(Quantity::from(100_000))
            .build();

        execution_engine
            .cache()
            .borrow_mut()
            .add_order(order1.clone(), None, Some(ClientId::from("STUB")), true)
            .unwrap();

        let position_id = PositionId::from("P-1");

        execution_engine.process(&TestOrderEventStubs::submitted(
            &order1,
            AccountId::test_default(),
        ));
        execution_engine.process(&TestOrderEventStubs::accepted(
            &order1,
            AccountId::test_default(),
            VenueOrderId::from("V-1"),
        ));
        execution_engine.process(&TestOrderEventStubs::filled(
            &order1,
            &instrument.clone().into(),
            Some(TradeId::new("T-1")),
            Some(position_id),
            None,
            None,
            None,
            None,
            None,
            Some(AccountId::test_default()),
        ));

        {
            let cache = execution_engine.cache().borrow();
            assert!(
                cache.position_snapshot_bytes(&position_id).is_none(),
                "Should have no snapshots before flip"
            );
        }

        let order2 = OrderTestBuilder::new(OrderType::Market)
            .trader_id(trader_id)
            .strategy_id(strategy_id)
            .instrument_id(instrument.id)
            .client_order_id(ClientOrderId::from("O-2"))
            .side(OrderSide::Sell)
            .quantity(Quantity::from(150_000))
            .build();

        execution_engine
            .cache()
            .borrow_mut()
            .add_order(order2.clone(), None, Some(ClientId::from("STUB")), true)
            .unwrap();

        execution_engine.process(&TestOrderEventStubs::submitted(
            &order2,
            AccountId::test_default(),
        ));
        execution_engine.process(&TestOrderEventStubs::accepted(
            &order2,
            AccountId::test_default(),
            VenueOrderId::from("V-2"),
        ));
        execution_engine.process(&TestOrderEventStubs::filled(
            &order2,
            &instrument.into(),
            Some(TradeId::new("T-2")),
            Some(position_id),
            None,
            None,
            None,
            None,
            None,
            Some(AccountId::test_default()),
        ));

        let cache = execution_engine.cache().borrow();
        assert!(
            cache.position_snapshot_bytes(&position_id).is_some(),
            "Should have snapshot after NETTING flip"
        );

        let position = cache.position(&position_id).unwrap();
        assert_eq!(position.side, PositionSide::Short);
        assert!(!position.is_closed());
        assert_eq!(position.quantity, Quantity::from(50_000));

        assert!(cache.is_position_open(&position_id));
        assert!(!cache.is_position_closed(&position_id));
    }

    #[rstest]
    fn test_hedging_flip_no_snapshot(mut execution_engine: ExecutionEngine) {
        let trader_id = TraderId::test_default();
        let strategy_id = StrategyId::test_default();
        let instrument = audusd_sim();

        let stub_client = StubExecutionClient::new(
            ClientId::from("STUB"),
            AccountId::test_default(),
            Venue::test_default(),
            OmsType::Hedging,
            None,
        );
        execution_engine
            .register_client(Box::new(stub_client))
            .unwrap();

        execution_engine
            .cache()
            .borrow_mut()
            .add_instrument(instrument.clone().into())
            .unwrap();

        let account = CashAccount::default();
        execution_engine
            .cache()
            .borrow_mut()
            .add_account(account.into())
            .unwrap();

        let order1 = OrderTestBuilder::new(OrderType::Market)
            .trader_id(trader_id)
            .strategy_id(strategy_id)
            .instrument_id(instrument.id)
            .client_order_id(ClientOrderId::from("O-1"))
            .side(OrderSide::Buy)
            .quantity(Quantity::from(100_000))
            .build();

        execution_engine
            .cache()
            .borrow_mut()
            .add_order(order1.clone(), None, Some(ClientId::from("STUB")), true)
            .unwrap();

        let position_id1 = PositionId::from("P-19700101-000000-000-001-1");

        execution_engine.process(&TestOrderEventStubs::submitted(
            &order1,
            AccountId::test_default(),
        ));
        execution_engine.process(&TestOrderEventStubs::accepted(
            &order1,
            AccountId::test_default(),
            VenueOrderId::from("V-1"),
        ));
        execution_engine.process(&TestOrderEventStubs::filled(
            &order1,
            &instrument.clone().into(),
            Some(TradeId::new("T-1")),
            Some(position_id1),
            None,
            None,
            None,
            None,
            None,
            Some(AccountId::test_default()),
        ));

        let order2 = OrderTestBuilder::new(OrderType::Market)
            .trader_id(trader_id)
            .strategy_id(strategy_id)
            .instrument_id(instrument.id)
            .client_order_id(ClientOrderId::from("O-2"))
            .side(OrderSide::Sell)
            .quantity(Quantity::from(150_000))
            .build();

        execution_engine
            .cache()
            .borrow_mut()
            .add_order(order2.clone(), None, Some(ClientId::from("STUB")), true)
            .unwrap();

        execution_engine.process(&TestOrderEventStubs::submitted(
            &order2,
            AccountId::test_default(),
        ));
        execution_engine.process(&TestOrderEventStubs::accepted(
            &order2,
            AccountId::test_default(),
            VenueOrderId::from("V-2"),
        ));
        execution_engine.process(&TestOrderEventStubs::filled(
            &order2,
            &instrument.into(),
            Some(TradeId::new("T-2")),
            Some(position_id1),
            None,
            None,
            None,
            None,
            None,
            Some(AccountId::test_default()),
        ));

        let cache = execution_engine.cache().borrow();
        assert!(
            cache.position_snapshot_bytes(&position_id1).is_none(),
            "HEDGING mode should not create snapshots (new position ID used)"
        );

        // Original position should be closed
        let position1 = cache.position(&position_id1).unwrap();
        assert!(position1.is_closed());

        // New flipped position should exist with different ID
        let positions = cache.positions_open(None, None, None, None, None);
        assert_eq!(positions.len(), 1, "Should have 1 open position");
        assert_ne!(
            positions[0].id, position_id1,
            "Flipped position should have new ID"
        );
        assert_eq!(positions[0].side, PositionSide::Short);
        assert_eq!(positions[0].quantity, Quantity::from(50_000));
    }

    #[rstest]
    fn test_netting_reopen_creates_snapshot(mut execution_engine: ExecutionEngine) {
        let trader_id = TraderId::test_default();
        let strategy_id = StrategyId::test_default();
        let instrument = audusd_sim();

        let stub_client = StubExecutionClient::new(
            ClientId::from("STUB"),
            AccountId::test_default(),
            Venue::test_default(),
            OmsType::Netting,
            None,
        );
        execution_engine
            .register_client(Box::new(stub_client))
            .unwrap();

        execution_engine
            .cache()
            .borrow_mut()
            .add_instrument(instrument.clone().into())
            .unwrap();

        let account = CashAccount::default();
        execution_engine
            .cache()
            .borrow_mut()
            .add_account(account.into())
            .unwrap();

        let position_id = PositionId::from("P-1");

        // Open LONG position
        let order1 = OrderTestBuilder::new(OrderType::Market)
            .trader_id(trader_id)
            .strategy_id(strategy_id)
            .instrument_id(instrument.id)
            .client_order_id(ClientOrderId::from("O-1"))
            .side(OrderSide::Buy)
            .quantity(Quantity::from(100_000))
            .build();

        execution_engine
            .cache()
            .borrow_mut()
            .add_order(order1.clone(), None, Some(ClientId::from("STUB")), true)
            .unwrap();

        execution_engine.process(&TestOrderEventStubs::submitted(
            &order1,
            AccountId::test_default(),
        ));
        execution_engine.process(&TestOrderEventStubs::accepted(
            &order1,
            AccountId::test_default(),
            VenueOrderId::from("V-1"),
        ));
        execution_engine.process(&TestOrderEventStubs::filled(
            &order1,
            &instrument.clone().into(),
            Some(TradeId::new("T-1")),
            Some(position_id),
            None,
            None,
            None,
            None,
            None,
            Some(AccountId::test_default()),
        ));

        // Close to FLAT
        let order2 = OrderTestBuilder::new(OrderType::Market)
            .trader_id(trader_id)
            .strategy_id(strategy_id)
            .instrument_id(instrument.id)
            .client_order_id(ClientOrderId::from("O-2"))
            .side(OrderSide::Sell)
            .quantity(Quantity::from(100_000))
            .build();

        execution_engine
            .cache()
            .borrow_mut()
            .add_order(order2.clone(), None, Some(ClientId::from("STUB")), true)
            .unwrap();

        execution_engine.process(&TestOrderEventStubs::submitted(
            &order2,
            AccountId::test_default(),
        ));
        execution_engine.process(&TestOrderEventStubs::accepted(
            &order2,
            AccountId::test_default(),
            VenueOrderId::from("V-2"),
        ));
        execution_engine.process(&TestOrderEventStubs::filled(
            &order2,
            &instrument.clone().into(),
            Some(TradeId::new("T-2")),
            Some(position_id),
            None,
            None,
            None,
            None,
            None,
            Some(AccountId::test_default()),
        ));

        {
            let cache = execution_engine.cache().borrow();
            let position = cache.position(&position_id).unwrap();
            assert!(position.is_closed());
            assert!(cache.is_position_closed(&position_id));
        }

        let order3 = OrderTestBuilder::new(OrderType::Market)
            .trader_id(trader_id)
            .strategy_id(strategy_id)
            .instrument_id(instrument.id)
            .client_order_id(ClientOrderId::from("O-3"))
            .side(OrderSide::Buy)
            .quantity(Quantity::from(50_000))
            .build();

        execution_engine
            .cache()
            .borrow_mut()
            .add_order(order3.clone(), None, Some(ClientId::from("STUB")), true)
            .unwrap();

        execution_engine.process(&TestOrderEventStubs::submitted(
            &order3,
            AccountId::test_default(),
        ));
        execution_engine.process(&TestOrderEventStubs::accepted(
            &order3,
            AccountId::test_default(),
            VenueOrderId::from("V-3"),
        ));
        execution_engine.process(&TestOrderEventStubs::filled(
            &order3,
            &instrument.into(),
            Some(TradeId::new("T-3")),
            Some(position_id),
            None,
            None,
            None,
            None,
            None,
            Some(AccountId::test_default()),
        ));

        let cache = execution_engine.cache().borrow();
        assert!(
            cache.position_snapshot_bytes(&position_id).is_some(),
            "Should have snapshot after NETTING reopen"
        );

        let position = cache.position(&position_id).unwrap();
        assert_eq!(position.side, PositionSide::Long);
        assert!(!position.is_closed());
        assert_eq!(position.quantity, Quantity::from(50_000));

        assert!(cache.is_position_open(&position_id));
        assert!(!cache.is_position_closed(&position_id));
    }
}

fn setup_netting_snapshot_engine(
    execution_engine: &mut ExecutionEngine,
    instrument: &CurrencyPair,
) {
    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        AccountId::test_default(),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();
    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(CashAccount::default().into())
        .unwrap();
}

#[expect(clippy::too_many_arguments)]
fn process_filled_order(
    execution_engine: &mut ExecutionEngine,
    trader_id: TraderId,
    strategy_id: StrategyId,
    instrument: &CurrencyPair,
    client_order_id: &str,
    venue_order_id: &str,
    trade_id: &str,
    side: OrderSide,
    quantity: u64,
    position_id: PositionId,
) {
    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from(client_order_id))
        .side(side)
        .quantity(Quantity::from(quantity))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();
    execution_engine.process(&TestOrderEventStubs::submitted(
        &order,
        AccountId::test_default(),
    ));
    execution_engine.process(&TestOrderEventStubs::accepted(
        &order,
        AccountId::test_default(),
        VenueOrderId::from(venue_order_id),
    ));

    let instrument_any: InstrumentAny = instrument.clone().into();
    execution_engine.process(&TestOrderEventStubs::filled(
        &order,
        &instrument_any,
        Some(TradeId::new(trade_id)),
        Some(position_id),
        None,
        None,
        None,
        None,
        None,
        Some(AccountId::test_default()),
    ));
}

#[rstest]
fn test_snapshot_anchorer_runs_on_netting_flip(mut execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();
    let position_id = PositionId::new(format!("{}-{strategy_id}", instrument.id));
    setup_netting_snapshot_engine(&mut execution_engine, &instrument);

    process_filled_order(
        &mut execution_engine,
        trader_id,
        strategy_id,
        &instrument,
        "O-ANCHOR-FLIP-1",
        "V-ANCHOR-FLIP-1",
        "T-ANCHOR-FLIP-1",
        OrderSide::Buy,
        100_000,
        position_id,
    );

    let anchors = Rc::new(RefCell::new(Vec::<CacheSnapshotRef>::new()));
    let anchors_for_cb = Rc::clone(&anchors);
    execution_engine.set_snapshot_anchorer(Some(Rc::new(move |snapshot_ref| {
        anchors_for_cb.borrow_mut().push(snapshot_ref);
        Ok(())
    })));

    process_filled_order(
        &mut execution_engine,
        trader_id,
        strategy_id,
        &instrument,
        "O-ANCHOR-FLIP-2",
        "V-ANCHOR-FLIP-2",
        "T-ANCHOR-FLIP-2",
        OrderSide::Sell,
        150_000,
        position_id,
    );

    let cache = execution_engine.cache().borrow();
    let frames = cache
        .position_snapshot_bytes(&position_id)
        .expect("position snapshot");
    let anchors = anchors.borrow();
    let position = cache.position(&position_id).expect("position");

    assert_eq!(anchors.len(), 1);
    assert_eq!(
        anchors[0].blob_ref,
        format!("cache://position-snapshots/{}/0", position_id.as_str()),
    );
    assert_eq!(anchors[0].blob.as_ref(), frames[0].as_slice());
    assert_eq!(position.side, PositionSide::Short);
    assert!(!position.is_closed());
}

#[rstest]
fn test_snapshot_anchorer_error_does_not_stop_netting_reopen(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();
    let position_id = PositionId::new(format!("{}-{strategy_id}", instrument.id));
    setup_netting_snapshot_engine(&mut execution_engine, &instrument);

    process_filled_order(
        &mut execution_engine,
        trader_id,
        strategy_id,
        &instrument,
        "O-ANCHOR-REOPEN-1",
        "V-ANCHOR-REOPEN-1",
        "T-ANCHOR-REOPEN-1",
        OrderSide::Buy,
        100_000,
        position_id,
    );
    process_filled_order(
        &mut execution_engine,
        trader_id,
        strategy_id,
        &instrument,
        "O-ANCHOR-REOPEN-2",
        "V-ANCHOR-REOPEN-2",
        "T-ANCHOR-REOPEN-2",
        OrderSide::Sell,
        100_000,
        position_id,
    );

    let anchors = Rc::new(RefCell::new(Vec::<CacheSnapshotRef>::new()));
    let anchors_for_cb = Rc::clone(&anchors);
    execution_engine.set_snapshot_anchorer(Some(Rc::new(move |snapshot_ref| {
        anchors_for_cb.borrow_mut().push(snapshot_ref);
        Err(anyhow::anyhow!("anchor write failed"))
    })));

    process_filled_order(
        &mut execution_engine,
        trader_id,
        strategy_id,
        &instrument,
        "O-ANCHOR-REOPEN-3",
        "V-ANCHOR-REOPEN-3",
        "T-ANCHOR-REOPEN-3",
        OrderSide::Buy,
        50_000,
        position_id,
    );

    let cache = execution_engine.cache().borrow();
    let frames = cache
        .position_snapshot_bytes(&position_id)
        .expect("position snapshot");
    let anchors = anchors.borrow();
    let position = cache.position(&position_id).expect("position");

    assert_eq!(anchors.len(), 1);
    assert_eq!(
        anchors[0].blob_ref,
        format!("cache://position-snapshots/{}/0", position_id.as_str()),
    );
    assert_eq!(anchors[0].blob.as_ref(), frames[0].as_slice());
    assert_eq!(position.side, PositionSide::Long);
    assert!(!position.is_closed());
}

fn create_order_status_report(
    client_order_id: Option<ClientOrderId>,
    venue_order_id: VenueOrderId,
    instrument_id: InstrumentId,
    status: OrderStatus,
    quantity: Quantity,
    filled_qty: Quantity,
) -> OrderStatusReport {
    OrderStatusReport::new(
        AccountId::test_default(),
        instrument_id,
        client_order_id,
        venue_order_id,
        OrderSide::Buy,
        OrderType::Limit,
        TimeInForce::Gtc,
        status,
        quantity,
        filled_qty,
        UnixNanos::from(1_000_000),
        UnixNanos::from(1_000_000),
        UnixNanos::from(1_000_000),
        None,
    )
    .with_price(Price::from("1.00000"))
}

#[rstest]
fn test_reconcile_order_status_report_order_not_in_cache(mut execution_engine: ExecutionEngine) {
    let report = create_order_status_report(
        Some(ClientOrderId::from("O-MISSING")),
        VenueOrderId::from("V-001"),
        audusd_sim().id(),
        OrderStatus::Accepted,
        Quantity::from(100_000),
        Quantity::from(0),
    );

    execution_engine.reconcile_order_status_report(&report);

    let cache = execution_engine.cache().borrow();
    assert!(!cache.order_exists(&ClientOrderId::from("O-MISSING")));
}

#[rstest]
fn test_reconcile_order_status_report_generates_canceled_event(
    mut execution_engine: ExecutionEngine,
) {
    let instrument = audusd_sim();
    let order = OrderTestBuilder::new(OrderType::Limit)
        .instrument_id(instrument.id())
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from("1.00000"))
        .build();
    let client_order_id = order.client_order_id();
    let venue_order_id = VenueOrderId::from("V-001");
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, None, true)
        .unwrap();
    let submitted = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&submitted);
    let accepted = TestOrderEventStubs::accepted(&order, AccountId::test_default(), venue_order_id);
    execution_engine.process(&accepted);

    let report = create_order_status_report(
        Some(client_order_id),
        venue_order_id,
        instrument.id(),
        OrderStatus::Canceled,
        Quantity::from(100_000),
        Quantity::from(0),
    );
    execution_engine.reconcile_order_status_report(&report);

    let cache = execution_engine.cache().borrow();
    let order = cache.order(&client_order_id).unwrap();
    assert_eq!(order.status(), OrderStatus::Canceled);
}

#[rstest]
fn test_reconcile_order_status_report_no_event_when_in_sync(mut execution_engine: ExecutionEngine) {
    let instrument = audusd_sim();
    let order = OrderTestBuilder::new(OrderType::Limit)
        .instrument_id(instrument.id())
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from("1.00000"))
        .build();
    let client_order_id = order.client_order_id();
    let venue_order_id = VenueOrderId::from("V-001");
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, None, true)
        .unwrap();
    let submitted = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&submitted);
    let accepted = TestOrderEventStubs::accepted(&order, AccountId::test_default(), venue_order_id);
    execution_engine.process(&accepted);

    let report = create_order_status_report(
        Some(client_order_id),
        venue_order_id,
        instrument.id(),
        OrderStatus::Accepted,
        Quantity::from(100_000),
        Quantity::from(0),
    );
    execution_engine.reconcile_order_status_report(&report);

    let cache = execution_engine.cache().borrow();
    let order = cache.order(&client_order_id).unwrap();
    assert_eq!(order.status(), OrderStatus::Accepted);
}

#[rstest]
fn test_reconcile_order_status_report_finds_order_by_venue_order_id(
    mut execution_engine: ExecutionEngine,
) {
    let instrument = audusd_sim();
    let order = OrderTestBuilder::new(OrderType::Limit)
        .instrument_id(instrument.id())
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from("1.00000"))
        .build();
    let client_order_id = order.client_order_id();
    let venue_order_id = VenueOrderId::from("V-001");
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, None, true)
        .unwrap();
    let submitted = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&submitted);
    let accepted = TestOrderEventStubs::accepted(&order, AccountId::test_default(), venue_order_id);
    execution_engine.process(&accepted);

    let report = create_order_status_report(
        None,
        venue_order_id,
        instrument.id(),
        OrderStatus::Canceled,
        Quantity::from(100_000),
        Quantity::from(0),
    );
    execution_engine.reconcile_order_status_report(&report);

    let cache = execution_engine.cache().borrow();
    let order = cache.order(&client_order_id).unwrap();
    assert_eq!(order.status(), OrderStatus::Canceled);
}

fn create_fill_report(
    instrument_id: InstrumentId,
    client_order_id: Option<ClientOrderId>,
    venue_order_id: VenueOrderId,
    trade_id: TradeId,
    last_qty: Quantity,
    last_px: Price,
) -> FillReport {
    create_fill_report_with_account(
        AccountId::test_default(),
        instrument_id,
        client_order_id,
        venue_order_id,
        trade_id,
        last_qty,
        last_px,
    )
}

fn create_fill_report_with_account(
    account_id: AccountId,
    instrument_id: InstrumentId,
    client_order_id: Option<ClientOrderId>,
    venue_order_id: VenueOrderId,
    trade_id: TradeId,
    last_qty: Quantity,
    last_px: Price,
) -> FillReport {
    FillReport::new(
        account_id,
        instrument_id,
        venue_order_id,
        trade_id,
        OrderSide::Buy,
        last_qty,
        last_px,
        Money::new(0.10, Currency::USD()),
        LiquiditySide::Taker,
        client_order_id,
        None,
        UnixNanos::from(1_000_000),
        UnixNanos::from(1_000_000),
        None,
    )
}

fn cash_account_for(account_id: AccountId) -> CashAccount {
    let state = AccountState::new(
        account_id,
        AccountType::Cash,
        vec![AccountBalance::new(
            Money::from("1000000 USD"),
            Money::from("0 USD"),
            Money::from("1000000 USD"),
        )],
        vec![],
        true,
        UUID4::new(),
        UnixNanos::default(),
        UnixNanos::default(),
        Some(Currency::USD()),
    );
    CashAccount::new(state, true, false)
}

#[rstest]
fn test_reconcile_fill_report_bootstraps_external_order(mut execution_engine: ExecutionEngine) {
    let instrument = audusd_sim();
    let client_order_id = ClientOrderId::from("O-MISSING");
    let venue_order_id = VenueOrderId::from("V-001");

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(InstrumentAny::CurrencyPair(instrument.clone()))
        .unwrap();

    let report = create_fill_report(
        instrument.id(),
        Some(client_order_id),
        venue_order_id,
        TradeId::from("T-001"),
        Quantity::from(50_000),
        Price::from("1.00000"),
    );

    execution_engine.reconcile_fill_report(&report);

    // The engine creates an external order from the lone fill so venue-initiated
    // closures (e.g. Hyperliquid liquidations) that arrive without a companion
    // order status report still update the local order/position state.
    let cache = execution_engine.cache().borrow();
    let order = cache
        .order(&client_order_id)
        .expect("external order should be created from fill report");
    assert_eq!(order.order_type(), OrderType::Market);
    assert_eq!(order.quantity(), Quantity::from(50_000));
    assert_eq!(order.filled_qty(), Quantity::from(50_000));
    assert_eq!(order.status(), OrderStatus::Filled);
    assert_eq!(order.trade_ids().len(), 1);
    assert_eq!(*order.trade_ids()[0], TradeId::from("T-001"));
    // Lock the policy for venue-initiated closes: IOC, reduce-only, EXTERNAL strategy.
    assert_eq!(order.time_in_force(), TimeInForce::Ioc);
    assert!(order.is_reduce_only());
    assert_eq!(order.strategy_id(), StrategyId::from("EXTERNAL"));
}

#[rstest]
fn test_reconcile_fill_report_bootstrap_uses_claimed_strategy(
    mut execution_engine: ExecutionEngine,
) {
    let instrument = audusd_sim();
    let client_order_id = ClientOrderId::from("O-CLAIMED");
    let venue_order_id = VenueOrderId::from("V-CLAIMED-001");

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(InstrumentAny::CurrencyPair(instrument.clone()))
        .unwrap();

    let strategy_id = StrategyId::from("MyStrategy-001");
    let mut instruments = HashSet::new();
    instruments.insert(instrument.id());
    execution_engine
        .register_external_order_claims(strategy_id, &instruments)
        .unwrap();

    let report = create_fill_report(
        instrument.id(),
        Some(client_order_id),
        venue_order_id,
        TradeId::from("T-CLAIMED-001"),
        Quantity::from(50_000),
        Price::from("1.00000"),
    );

    execution_engine.reconcile_fill_report(&report);

    let cache = execution_engine.cache().borrow();
    let order = cache
        .order(&client_order_id)
        .expect("external order should be created from fill report");
    assert_eq!(order.strategy_id(), strategy_id);
}

#[rstest]
fn test_reconcile_fill_report_skips_when_instrument_missing(mut execution_engine: ExecutionEngine) {
    let instrument = audusd_sim();
    let client_order_id = ClientOrderId::from("O-MISSING");

    let report = create_fill_report(
        instrument.id(),
        Some(client_order_id),
        VenueOrderId::from("V-001"),
        TradeId::from("T-001"),
        Quantity::from(50_000),
        Price::from("1.00000"),
    );

    execution_engine.reconcile_fill_report(&report);

    // Without an instrument the engine cannot bootstrap an external order.
    let cache = execution_engine.cache().borrow();
    assert!(!cache.order_exists(&client_order_id));
}

#[rstest]
fn test_reconcile_fill_report_applies_fill_event(mut execution_engine: ExecutionEngine) {
    let instrument = audusd_sim();
    let client_order_id = ClientOrderId::from("O-001");
    let venue_order_id = VenueOrderId::from("V-001");

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(InstrumentAny::CurrencyPair(instrument.clone()))
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .instrument_id(instrument.id())
        .client_order_id(client_order_id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let submitted = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&submitted);

    let accepted = TestOrderEventStubs::accepted(&order, AccountId::test_default(), venue_order_id);
    execution_engine.process(&accepted);

    let report = create_fill_report(
        instrument.id(),
        Some(client_order_id),
        venue_order_id,
        TradeId::from("T-001"),
        Quantity::from(50_000),
        Price::from("1.00000"),
    );

    execution_engine.reconcile_fill_report(&report);

    let cache = execution_engine.cache().borrow();
    let order = cache.order(&client_order_id).unwrap();
    assert_eq!(order.filled_qty(), Quantity::from(50_000));
    assert_eq!(order.status(), OrderStatus::PartiallyFilled);
}

#[rstest]
fn test_reconcile_fill_report_finds_order_by_venue_order_id(mut execution_engine: ExecutionEngine) {
    let instrument = audusd_sim();
    let client_order_id = ClientOrderId::from("O-001");
    let venue_order_id = VenueOrderId::from("V-001");

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(InstrumentAny::CurrencyPair(instrument.clone()))
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .instrument_id(instrument.id())
        .client_order_id(client_order_id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let submitted = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&submitted);

    let accepted = TestOrderEventStubs::accepted(&order, AccountId::test_default(), venue_order_id);
    execution_engine.process(&accepted);

    // Report without client_order_id - should find by venue_order_id
    let report = create_fill_report(
        instrument.id(),
        None,
        venue_order_id,
        TradeId::from("T-001"),
        Quantity::from(100_000),
        Price::from("1.00000"),
    );

    execution_engine.reconcile_fill_report(&report);

    let cache = execution_engine.cache().borrow();
    let order = cache.order(&client_order_id).unwrap();
    assert_eq!(order.filled_qty(), Quantity::from(100_000));
    assert_eq!(order.status(), OrderStatus::Filled);
}

#[rstest]
fn test_reconcile_fill_report_uses_report_account_for_position(
    mut execution_engine: ExecutionEngine,
) {
    let instrument = audusd_sim();
    let client_order_id = ClientOrderId::from("O-ACCOUNT-001");
    let venue_order_id = VenueOrderId::from("V-ACCOUNT-001");
    let report_account_id = AccountId::from("A-001");
    let order_account_id = AccountId::from("B-001");

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(InstrumentAny::CurrencyPair(instrument.clone()))
        .unwrap();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(cash_account_for(report_account_id).into())
        .unwrap();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(cash_account_for(order_account_id).into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .instrument_id(instrument.id())
        .client_order_id(client_order_id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    execution_engine.process(&TestOrderEventStubs::submitted(&order, order_account_id));
    execution_engine.process(&TestOrderEventStubs::accepted(
        &order,
        order_account_id,
        venue_order_id,
    ));

    let report = create_fill_report_with_account(
        report_account_id,
        instrument.id(),
        Some(client_order_id),
        venue_order_id,
        TradeId::from("T-ACCOUNT-001"),
        Quantity::from(50_000),
        Price::from("1.00000"),
    );

    execution_engine.reconcile_fill_report(&report);

    let cache = execution_engine.cache().borrow();
    let report_account_positions = cache.positions(
        None,
        Some(&instrument.id()),
        None,
        Some(&report_account_id),
        None,
    );
    let order_account_positions = cache.positions(
        None,
        Some(&instrument.id()),
        None,
        Some(&order_account_id),
        None,
    );

    assert_eq!(report_account_positions.len(), 1);
    assert_eq!(report_account_positions[0].account_id, report_account_id);
    assert_eq!(report_account_positions[0].instrument_id, instrument.id());
    assert!(order_account_positions.is_empty());
}

#[rstest]
fn test_handle_fill_skips_duplicate_trade_id_already_on_position(
    mut execution_engine: ExecutionEngine,
) {
    let instrument = audusd_sim();
    let instrument_any = InstrumentAny::CurrencyPair(instrument.clone());
    let account_id = AccountId::test_default();
    let trade_id = TradeId::from("T-POS-DUP");
    let order_1_id = ClientOrderId::from("O-POS-DUP-1");
    let order_2_id = ClientOrderId::from("O-POS-DUP-2");

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument_any.clone())
        .unwrap();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(CashAccount::default().into())
        .unwrap();

    let order_1 = OrderTestBuilder::new(OrderType::Market)
        .instrument_id(instrument.id())
        .client_order_id(order_1_id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();
    let order_2 = OrderTestBuilder::new(OrderType::Market)
        .instrument_id(instrument.id())
        .client_order_id(order_2_id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order_1.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order_2.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    execution_engine.process(&TestOrderEventStubs::submitted(&order_1, account_id));
    execution_engine.process(&TestOrderEventStubs::accepted(
        &order_1,
        account_id,
        VenueOrderId::from("V-POS-DUP-1"),
    ));
    execution_engine.process(&TestOrderEventStubs::submitted(&order_2, account_id));
    execution_engine.process(&TestOrderEventStubs::accepted(
        &order_2,
        account_id,
        VenueOrderId::from("V-POS-DUP-2"),
    ));

    let order_1 = execution_engine
        .cache()
        .borrow()
        .order(&order_1_id)
        .unwrap()
        .clone();
    let fill_1 = TestOrderEventStubs::filled(
        &order_1,
        &instrument_any,
        Some(trade_id),
        None,
        Some(Price::from("1.00000")),
        Some(Quantity::from(50_000)),
        Some(LiquiditySide::Taker),
        Some(Money::from("0 USD")),
        None,
        Some(account_id),
    );
    execution_engine.process(&fill_1);

    let order_2 = execution_engine
        .cache()
        .borrow()
        .order(&order_2_id)
        .unwrap()
        .clone();
    let fill_2 = TestOrderEventStubs::filled(
        &order_2,
        &instrument_any,
        Some(trade_id),
        None,
        Some(Price::from("1.00000")),
        Some(Quantity::from(50_000)),
        Some(LiquiditySide::Taker),
        Some(Money::from("0 USD")),
        None,
        Some(account_id),
    );
    execution_engine.process(&fill_2);

    let cache = execution_engine.cache().borrow();
    let order_2 = cache.order(&order_2_id).unwrap();
    let positions = cache.positions(None, Some(&instrument.id()), None, Some(&account_id), None);

    assert_eq!(order_2.status(), OrderStatus::Accepted);
    assert_eq!(order_2.filled_qty(), Quantity::from(0));
    assert_eq!(positions.len(), 1);
    assert_eq!(positions[0].quantity, Quantity::from(50_000));
    assert!(positions[0].trade_ids.contains(&trade_id));
}

fn create_position_report(
    instrument_id: InstrumentId,
    position_side: PositionSideSpecified,
    quantity: Quantity,
    venue_position_id: Option<PositionId>,
) -> PositionStatusReport {
    PositionStatusReport::new(
        AccountId::test_default(),
        instrument_id,
        position_side,
        quantity,
        UnixNanos::from(1_000_000),
        UnixNanos::from(1_000_000),
        None, // report_id
        venue_position_id,
        None, // avg_px_open
    )
}

#[rstest]
fn test_reconcile_position_report_netting_mode(mut execution_engine: ExecutionEngine) {
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(InstrumentAny::CurrencyPair(instrument.clone()))
        .unwrap();

    // No venue_position_id = netting mode
    let report = create_position_report(
        instrument.id(),
        PositionSideSpecified::Long,
        Quantity::from(100_000),
        None,
    );

    execution_engine.reconcile_position_report(&report);
}

#[rstest]
fn test_reconcile_position_report_hedging_mode_position_not_found(
    mut execution_engine: ExecutionEngine,
) {
    let instrument = audusd_sim();
    let venue_position_id = PositionId::from("P-001");

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(InstrumentAny::CurrencyPair(instrument.clone()))
        .unwrap();

    // With venue_position_id = hedging mode
    let report = create_position_report(
        instrument.id(),
        PositionSideSpecified::Long,
        Quantity::from(100_000),
        Some(venue_position_id),
    );

    execution_engine.reconcile_position_report(&report);
}

#[rstest]
fn test_reconcile_execution_mass_status_empty(mut execution_engine: ExecutionEngine) {
    let mass_status = ExecutionMassStatus::new(
        ClientId::from("SIM"),
        AccountId::test_default(),
        Venue::from("SIM"),
        UnixNanos::from(1_000_000),
        None,
    );

    execution_engine.reconcile_execution_mass_status(&mass_status);

    assert_eq!(execution_engine.report_count(), 1);

    execution_engine.reset();
    execution_engine
        .reconcile_execution_report(&ExecutionReport::MassStatus(Box::new(mass_status)));

    assert_eq!(execution_engine.report_count(), 1);
}

#[rstest]
fn test_reconcile_execution_mass_status_with_order_reports(mut execution_engine: ExecutionEngine) {
    let instrument = audusd_sim();
    let client_order_id = ClientOrderId::from("O-001");
    let venue_order_id = VenueOrderId::from("V-001");

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(InstrumentAny::CurrencyPair(instrument.clone()))
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Limit)
        .instrument_id(instrument.id())
        .client_order_id(client_order_id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from("1.00000"))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let submitted = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&submitted);

    let accepted = TestOrderEventStubs::accepted(&order, AccountId::test_default(), venue_order_id);
    execution_engine.process(&accepted);

    let order_report = create_order_status_report(
        Some(client_order_id),
        venue_order_id,
        instrument.id(),
        OrderStatus::Canceled,
        Quantity::from(100_000),
        Quantity::from(0),
    );

    let mut mass_status = ExecutionMassStatus::new(
        ClientId::from("SIM"),
        AccountId::test_default(),
        Venue::from("SIM"),
        UnixNanos::from(1_000_000),
        None,
    );
    mass_status.add_order_reports(vec![order_report]);

    execution_engine.reconcile_execution_mass_status(&mass_status);

    let cache = execution_engine.cache().borrow();
    let order = cache.order(&client_order_id).unwrap();
    assert_eq!(order.status(), OrderStatus::Canceled);
}

#[rstest]
fn test_reconcile_execution_mass_status_publishes_skipped_external_fill(
    mut execution_engine: ExecutionEngine,
) {
    // External-order fills are skipped by the per-report reconciliation path
    // (covered by an inferred fill), but they still arrived from the venue and
    // must be captured for forensic replay on the raw FillReport topic.
    let instrument = audusd_sim();
    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(InstrumentAny::CurrencyPair(instrument.clone()))
        .unwrap();

    let venue_order_id = VenueOrderId::from("V-EXT-FILL");
    let order_report = create_order_status_report(
        None, // no client_order_id triggers external-order creation
        venue_order_id,
        instrument.id(),
        OrderStatus::Filled,
        Quantity::from(100_000),
        Quantity::from(100_000),
    );
    let fill_report = FillReport::new(
        AccountId::test_default(),
        instrument.id(),
        venue_order_id,
        TradeId::from("T-EXT-FILL"),
        OrderSide::Buy,
        Quantity::from(100_000),
        Price::from("1.00000"),
        Money::new(0.0, Currency::USD()),
        LiquiditySide::Taker,
        None,
        None,
        UnixNanos::from(1_000_000),
        UnixNanos::from(1_000_000),
        None,
    );

    let mut mass_status = ExecutionMassStatus::new(
        ClientId::from("SIM"),
        AccountId::test_default(),
        Venue::from("SIM"),
        UnixNanos::from(1_000_000),
        None,
    );
    mass_status.add_order_reports(vec![order_report]);
    mass_status.add_fill_reports(vec![fill_report.clone()]);

    let raw_fill_topic = MessagingSwitchboard::reconciliation_raw_fill_report_topic();
    let pattern: msgbus::MStr<msgbus::Pattern> = raw_fill_topic.into();
    let (handler, saver) = get_any_saving_handler::<FillReport>(None);
    msgbus::subscribe_any(pattern, handler.clone(), None);

    execution_engine.reconcile_execution_mass_status(&mass_status);

    msgbus::unsubscribe_any(pattern, &handler);

    let captured = saver.get_messages();
    assert_eq!(
        captured.len(),
        1,
        "skipped external-order fill must still publish on the raw topic",
    );
    assert_eq!(captured[0], fill_report);
}

#[rstest]
fn test_reconcile_order_status_report_publishes_raw_topic(mut execution_engine: ExecutionEngine) {
    // Each engine reconcile entry point must publish the raw venue report on
    // its `reconciliation.raw.*` topic before any state mutation, so forensic
    // replay can re-run reconciliation against the captured inputs.
    let instrument = audusd_sim();
    let client_order_id = ClientOrderId::from("O-RAW-STATUS");
    let venue_order_id = VenueOrderId::from("V-RAW-STATUS");

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(InstrumentAny::CurrencyPair(instrument.clone()))
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Limit)
        .instrument_id(instrument.id())
        .client_order_id(client_order_id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .price(Price::from("1.00000"))
        .build();
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();
    let submitted = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&submitted);

    let report = create_order_status_report(
        Some(client_order_id),
        venue_order_id,
        instrument.id(),
        OrderStatus::Accepted,
        Quantity::from(100_000),
        Quantity::from(0),
    );

    let topic = MessagingSwitchboard::reconciliation_raw_order_status_report_topic();
    let pattern: msgbus::MStr<msgbus::Pattern> = topic.into();
    let (handler, saver) = get_any_saving_handler::<OrderStatusReport>(None);
    msgbus::subscribe_any(pattern, handler.clone(), None);

    execution_engine.reconcile_order_status_report(&report);

    msgbus::unsubscribe_any(pattern, &handler);

    let captured = saver.get_messages();
    assert_eq!(
        captured.len(),
        1,
        "raw OrderStatusReport must be published once"
    );
    assert_eq!(captured[0], report);
}

#[rstest]
fn test_reconcile_fill_report_publishes_raw_topic(mut execution_engine: ExecutionEngine) {
    let instrument = audusd_sim();
    let client_order_id = ClientOrderId::from("O-RAW-FILL");
    let venue_order_id = VenueOrderId::from("V-RAW-FILL");

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(InstrumentAny::CurrencyPair(instrument.clone()))
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .instrument_id(instrument.id())
        .client_order_id(client_order_id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();
    let submitted = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&submitted);
    let accepted = TestOrderEventStubs::accepted(&order, AccountId::test_default(), venue_order_id);
    execution_engine.process(&accepted);

    let report = create_fill_report(
        instrument.id(),
        Some(client_order_id),
        venue_order_id,
        TradeId::from("T-RAW-FILL"),
        Quantity::from(50_000),
        Price::from("1.00000"),
    );

    let topic = MessagingSwitchboard::reconciliation_raw_fill_report_topic();
    let pattern: msgbus::MStr<msgbus::Pattern> = topic.into();
    let (handler, saver) = get_any_saving_handler::<FillReport>(None);
    msgbus::subscribe_any(pattern, handler.clone(), None);

    execution_engine.reconcile_fill_report(&report);

    msgbus::unsubscribe_any(pattern, &handler);

    let captured = saver.get_messages();
    assert_eq!(captured.len(), 1, "raw FillReport must be published once");
    assert_eq!(captured[0], report);
}

#[rstest]
fn test_reconcile_order_with_fills_publishes_order_and_each_fill(
    mut execution_engine: ExecutionEngine,
) {
    // Verifies the fan-out: one OrderStatusReport publish plus one FillReport
    // publish per fill in the slice, each on its matching raw topic.
    let instrument = audusd_sim();
    let client_order_id = ClientOrderId::from("O-RAW-BUNDLE");
    let venue_order_id = VenueOrderId::from("V-RAW-BUNDLE");

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(InstrumentAny::CurrencyPair(instrument.clone()))
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .instrument_id(instrument.id())
        .client_order_id(client_order_id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();
    let submitted = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&submitted);
    let accepted = TestOrderEventStubs::accepted(&order, AccountId::test_default(), venue_order_id);
    execution_engine.process(&accepted);

    let order_report = create_order_status_report(
        Some(client_order_id),
        venue_order_id,
        instrument.id(),
        OrderStatus::Filled,
        Quantity::from(100_000),
        Quantity::from(100_000),
    );
    let fill1 = create_fill_report(
        instrument.id(),
        Some(client_order_id),
        venue_order_id,
        TradeId::from("T-RAW-BUNDLE-1"),
        Quantity::from(30_000),
        Price::from("1.00000"),
    );
    let fill2 = create_fill_report(
        instrument.id(),
        Some(client_order_id),
        venue_order_id,
        TradeId::from("T-RAW-BUNDLE-2"),
        Quantity::from(40_000),
        Price::from("1.00001"),
    );
    let fill3 = create_fill_report(
        instrument.id(),
        Some(client_order_id),
        venue_order_id,
        TradeId::from("T-RAW-BUNDLE-3"),
        Quantity::from(30_000),
        Price::from("1.00002"),
    );

    let order_topic = MessagingSwitchboard::reconciliation_raw_order_status_report_topic();
    let fill_topic = MessagingSwitchboard::reconciliation_raw_fill_report_topic();
    let order_pattern: msgbus::MStr<msgbus::Pattern> = order_topic.into();
    let fill_pattern: msgbus::MStr<msgbus::Pattern> = fill_topic.into();
    let (order_handler, order_saver) = get_any_saving_handler::<OrderStatusReport>(None);
    let (fill_handler, fill_saver) = get_any_saving_handler::<FillReport>(None);
    msgbus::subscribe_any(order_pattern, order_handler.clone(), None);
    msgbus::subscribe_any(fill_pattern, fill_handler.clone(), None);

    execution_engine.reconcile_order_with_fills(
        &order_report,
        &[fill1.clone(), fill2.clone(), fill3.clone()],
    );

    msgbus::unsubscribe_any(order_pattern, &order_handler);
    msgbus::unsubscribe_any(fill_pattern, &fill_handler);

    let orders = order_saver.get_messages();
    assert_eq!(orders.len(), 1, "exactly one OrderStatusReport published");
    assert_eq!(orders[0], order_report);

    let fills = fill_saver.get_messages();
    assert_eq!(fills.len(), 3, "one publish per fill in the input slice");
    assert_eq!(fills[0], fill1);
    assert_eq!(fills[1], fill2);
    assert_eq!(fills[2], fill3);
}

#[rstest]
fn test_reconcile_position_report_publishes_raw_topic(mut execution_engine: ExecutionEngine) {
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(InstrumentAny::CurrencyPair(instrument.clone()))
        .unwrap();

    let report = create_position_report(
        instrument.id(),
        PositionSideSpecified::Long,
        Quantity::from(100_000),
        None,
    );

    let topic = MessagingSwitchboard::reconciliation_raw_position_status_report_topic();
    let pattern: msgbus::MStr<msgbus::Pattern> = topic.into();
    let (handler, saver) = get_any_saving_handler::<PositionStatusReport>(None);
    msgbus::subscribe_any(pattern, handler.clone(), None);

    execution_engine.reconcile_position_report(&report);

    msgbus::unsubscribe_any(pattern, &handler);

    let captured = saver.get_messages();
    assert_eq!(
        captured.len(),
        1,
        "raw PositionStatusReport must be published once"
    );
    assert_eq!(captured[0], report);
}

#[rstest]
fn test_get_all_clients_empty(execution_engine: ExecutionEngine) {
    let clients = execution_engine.get_all_clients();

    assert!(clients.is_empty());
}

#[rstest]
fn test_get_all_clients_with_registered_client(
    mut execution_engine: ExecutionEngine,
    stub_client: StubExecutionClient,
) {
    let client_id = stub_client.client_id();
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let clients = execution_engine.get_all_clients();

    assert_eq!(clients.len(), 1);
    assert_eq!(clients[0].client_id(), client_id);
}

#[rstest]
fn test_get_all_clients_includes_default_client(mut execution_engine: ExecutionEngine) {
    let default_client = StubExecutionClient::new(
        ClientId::from("DEFAULT"),
        AccountId::from("DEFAULT-ACCOUNT"),
        Venue::from("DEFAULT"),
        OmsType::Netting,
        None,
    );
    let default_id = default_client.client_id();
    execution_engine.register_default_client(Box::new(default_client));

    let clients = execution_engine.get_all_clients();

    assert_eq!(clients.len(), 1);
    assert_eq!(clients[0].client_id(), default_id);
}

#[rstest]
fn test_get_all_clients_with_registered_and_default(
    mut execution_engine: ExecutionEngine,
    stub_client: StubExecutionClient,
) {
    let registered_id = stub_client.client_id();
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    let default_client = StubExecutionClient::new(
        ClientId::from("DEFAULT"),
        AccountId::from("DEFAULT-ACCOUNT"),
        Venue::from("DEFAULT"),
        OmsType::Netting,
        None,
    );
    let default_id = default_client.client_id();
    execution_engine.register_default_client(Box::new(default_client));

    let clients = execution_engine.get_all_clients();
    let client_ids: HashSet<ClientId> = clients.iter().map(|c| c.client_id()).collect();

    assert_eq!(clients.len(), 2);
    assert!(client_ids.contains(&registered_id));
    assert!(client_ids.contains(&default_id));
}

#[rstest]
fn test_submit_order_with_no_client_denies_order(execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-19700101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(10))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, None, true)
        .unwrap();

    let submit_order = SubmitOrder {
        trader_id,
        strategy_id,
        instrument_id: instrument.id,
        client_order_id: order.client_order_id(),
        order_init: order.init_event().clone(),
        position_id: None,
        params: None,
        client_id: None,
        exec_algorithm_id: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    // No clients registered, no default client: should deny the order
    execution_engine.execute(TradingCommand::SubmitOrder(submit_order));

    let cache = execution_engine.cache().borrow();
    let cached_order = cache.order(&order.client_order_id()).unwrap();
    assert_eq!(cached_order.status(), OrderStatus::Denied);
}

#[rstest]
fn test_register_client_errors_on_duplicate_venue(mut execution_engine: ExecutionEngine) {
    let client_a = StubExecutionClient::new(
        ClientId::from("CLIENT_A"),
        AccountId::from("ACCOUNT-A"),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    let client_b = StubExecutionClient::new(
        ClientId::from("CLIENT_B"),
        AccountId::from("ACCOUNT-B"),
        Venue::test_default(),
        OmsType::Netting,
        None,
    );

    execution_engine
        .register_client(Box::new(client_a))
        .unwrap();

    let result = execution_engine.register_client(Box::new(client_b));
    assert!(result.is_err());
    assert!(
        result
            .unwrap_err()
            .to_string()
            .contains("already routed to CLIENT_A"),
    );
}

#[rstest]
fn test_submit_order_list_with_no_client_denies_all_orders(execution_engine: ExecutionEngine) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let instrument = audusd_sim();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let entry = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-19700101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    let stop_loss = OrderTestBuilder::new(OrderType::StopMarket)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-19700101-000000-001-002-1"))
        .side(OrderSide::Sell)
        .quantity(Quantity::from(100_000))
        .trigger_price(Price::from_str("0.50000").unwrap())
        .build();

    let orders = [entry.clone(), stop_loss.clone()];

    for order in &orders {
        execution_engine
            .cache()
            .borrow_mut()
            .add_order(order.clone(), None, None, true)
            .unwrap();
    }

    let order_list = OrderList::new(
        OrderListId::from("1"),
        instrument.id,
        strategy_id,
        vec![entry.client_order_id(), stop_loss.client_order_id()],
        UnixNanos::default(),
    );

    let submit_order_list = SubmitOrderList {
        trader_id,
        client_id: None,
        strategy_id,
        instrument_id: instrument.id,
        order_list,
        order_inits: orders.iter().map(|o| o.init_event().clone()).collect(),
        exec_algorithm_id: None,
        position_id: None,
        params: None,
        command_id: UUID4::new(),
        ts_init: UnixNanos::default(),
    };

    // No clients registered: all child orders should be denied
    execution_engine.execute(TradingCommand::SubmitOrderList(submit_order_list));

    let cache = execution_engine.cache().borrow();
    let cached_entry = cache.order(&entry.client_order_id()).unwrap();
    let cached_stop = cache.order(&stop_loss.client_order_id()).unwrap();
    assert_eq!(cached_entry.status(), OrderStatus::Denied);
    assert_eq!(cached_stop.status(), OrderStatus::Denied);
}

#[rstest]
fn test_start_purge_timers_registers_when_configured() {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        purge_closed_orders_interval_mins: Some(5),
        purge_closed_positions_interval_mins: Some(10),
        purge_account_events_interval_mins: Some(15),
        ..Default::default()
    };

    let mut engine = ExecutionEngine::new(clock.clone(), cache, Some(config));
    engine.start();

    let names = clock
        .borrow()
        .timer_names()
        .into_iter()
        .map(String::from)
        .collect::<Vec<_>>();
    assert!(names.contains(&"ExecEngine_PURGE_CLOSED_ORDERS".to_string()));
    assert!(names.contains(&"ExecEngine_PURGE_CLOSED_POSITIONS".to_string()));
    assert!(names.contains(&"ExecEngine_PURGE_ACCOUNT_EVENTS".to_string()));
    assert_eq!(clock.borrow().timer_count(), 3);
}

#[rstest]
fn test_start_purge_timers_not_registered_when_unconfigured() {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));

    let mut engine = ExecutionEngine::new(clock.clone(), cache, None);
    engine.start();

    assert_eq!(clock.borrow().timer_count(), 0);
}

#[rstest]
fn test_start_purge_timers_zero_interval_skipped() {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        purge_closed_orders_interval_mins: Some(0),
        purge_closed_positions_interval_mins: Some(0),
        purge_account_events_interval_mins: Some(0),
        ..Default::default()
    };

    let mut engine = ExecutionEngine::new(clock.clone(), cache, Some(config));
    engine.start();

    assert_eq!(clock.borrow().timer_count(), 0);
}

#[rstest]
fn test_stop_purge_timers_cancels_timers() {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        purge_closed_orders_interval_mins: Some(5),
        purge_closed_positions_interval_mins: Some(10),
        purge_account_events_interval_mins: Some(15),
        ..Default::default()
    };

    let mut engine = ExecutionEngine::new(clock.clone(), cache, Some(config));
    engine.start();
    assert_eq!(clock.borrow().timer_count(), 3);

    engine.stop();
    assert_eq!(clock.borrow().timer_count(), 0);
}

#[rstest]
fn test_purge_closed_orders_timer_fires_callback() {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));

    let instrument = InstrumentAny::CurrencyPair(audusd_sim());
    cache
        .borrow_mut()
        .add_instrument(instrument.clone())
        .unwrap();

    let account_id = AccountId::new("SIM-001");
    let mut order = OrderTestBuilder::new(OrderType::Limit)
        .instrument_id(instrument.id())
        .side(OrderSide::Buy)
        .price(Price::from("1.00000"))
        .quantity(Quantity::from(100_000))
        .build();

    cache
        .borrow_mut()
        .add_order(order.clone(), None, None, false)
        .unwrap();

    let submitted = TestOrderEventStubs::submitted(&order, account_id);
    order = cache.borrow_mut().update_order(&submitted).unwrap();

    let accepted = TestOrderEventStubs::accepted(&order, account_id, VenueOrderId::new("V-001"));
    order = cache.borrow_mut().update_order(&accepted).unwrap();

    let filled = TestOrderEventStubs::filled(
        &order,
        &instrument,
        Some(TradeId::new("T-1")),
        None,
        Some(Price::from("1.00000")),
        None,
        None,
        None,
        None,
        None,
    );
    order = cache.borrow_mut().update_order(&filled).unwrap();

    assert!(order.is_closed());

    let config = ExecutionEngineConfig {
        purge_closed_orders_interval_mins: Some(1),
        purge_closed_orders_buffer_mins: Some(0),
        ..Default::default()
    };

    let mut engine = ExecutionEngine::new(clock.clone(), cache.clone(), Some(config));
    engine.start();

    assert_eq!(
        cache
            .borrow()
            .orders_closed(None, None, None, None, None)
            .len(),
        1
    );

    let interval_ns = NANOSECONDS_IN_MINUTE;
    let events = clock
        .borrow_mut()
        .advance_time(UnixNanos::from(interval_ns + 1), true);
    let handlers = clock.borrow().match_handlers(events);
    for handler in handlers {
        handler.callback.call(handler.event);
    }

    assert_eq!(
        cache
            .borrow()
            .orders_closed(None, None, None, None, None)
            .len(),
        0
    );
}

#[rstest]
fn test_reconcile_order_status_report_creates_external_order_when_filled(
    mut execution_engine: ExecutionEngine,
) {
    let instrument = audusd_sim();
    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let report = create_order_status_report(
        Some(ClientOrderId::from("autoclose-001")),
        VenueOrderId::from("V-EXT-001"),
        instrument.id(),
        OrderStatus::Filled,
        Quantity::from(100_000),
        Quantity::from(100_000),
    );

    execution_engine.reconcile_order_status_report(&report);

    let cache = execution_engine.cache().borrow();
    let order = cache
        .order(&ClientOrderId::from("autoclose-001"))
        .expect("external order should be in cache");
    assert_eq!(order.status(), OrderStatus::Filled);
    assert_eq!(order.strategy_id(), StrategyId::from("EXTERNAL"));
}

#[rstest]
fn test_reconcile_order_status_report_creates_external_order_accepted(
    mut execution_engine: ExecutionEngine,
) {
    let instrument = audusd_sim();
    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let report = create_order_status_report(
        None,
        VenueOrderId::from("V-EXT-002"),
        instrument.id(),
        OrderStatus::Accepted,
        Quantity::from(50_000),
        Quantity::from(0),
    );

    execution_engine.reconcile_order_status_report(&report);

    let cache = execution_engine.cache().borrow();
    let client_order_id = ClientOrderId::from("V-EXT-002");
    let order = cache
        .order(&client_order_id)
        .expect("external order should be in cache");
    assert_eq!(order.status(), OrderStatus::Accepted);
    assert_eq!(order.quantity(), Quantity::from(50_000));
}

#[rstest]
fn test_reconcile_order_status_report_external_order_bootstraps_own_book() {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        manage_own_order_books: true,
        ..Default::default()
    };
    let mut execution_engine = ExecutionEngine::new(clock, cache, Some(config));

    let instrument = audusd_sim();
    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let report = create_order_status_report(
        Some(ClientOrderId::from("external-open-001")),
        VenueOrderId::from("V-EXT-OWN-001"),
        instrument.id(),
        OrderStatus::Accepted,
        Quantity::from(50_000),
        Quantity::from(0),
    );

    execution_engine.reconcile_order_status_report(&report);

    let cache = execution_engine.cache().borrow();
    let order = cache
        .order(&ClientOrderId::from("external-open-001"))
        .expect("external order should be in cache");
    let own_book = cache
        .own_order_book(&instrument.id())
        .expect("own book should be initialized for external open order");

    assert_eq!(order.status(), OrderStatus::Accepted);
    assert!(own_book.is_order_in_book(&order.client_order_id()));
    assert_eq!(
        own_book.bid_client_order_ids(),
        vec![order.client_order_id()]
    );
    assert!(own_book.ask_client_order_ids().is_empty());
}

#[rstest]
fn test_reconcile_order_status_report_external_order_uses_claimed_strategy(
    mut execution_engine: ExecutionEngine,
) {
    let instrument = audusd_sim();
    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let strategy_id = StrategyId::from("MyStrategy-001");
    let mut instruments = HashSet::new();
    instruments.insert(instrument.id());
    execution_engine
        .register_external_order_claims(strategy_id, &instruments)
        .unwrap();

    let report = create_order_status_report(
        Some(ClientOrderId::from("adl_autoclose-001")),
        VenueOrderId::from("V-EXT-003"),
        instrument.id(),
        OrderStatus::Filled,
        Quantity::from(100_000),
        Quantity::from(100_000),
    );

    execution_engine.reconcile_order_status_report(&report);

    let cache = execution_engine.cache().borrow();
    let order = cache
        .order(&ClientOrderId::from("adl_autoclose-001"))
        .expect("external order should be in cache");
    assert_eq!(order.strategy_id(), strategy_id);
    assert_eq!(order.status(), OrderStatus::Filled);
}

#[rstest]
fn test_reconcile_order_status_report_external_order_adds_venue_order_id_index(
    mut execution_engine: ExecutionEngine,
) {
    let instrument = audusd_sim();
    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let report = create_order_status_report(
        Some(ClientOrderId::from("settlement-001")),
        VenueOrderId::from("V-EXT-004"),
        instrument.id(),
        OrderStatus::Filled,
        Quantity::from(100_000),
        Quantity::from(100_000),
    );

    execution_engine.reconcile_order_status_report(&report);

    let cache = execution_engine.cache().borrow();
    let resolved = cache.client_order_id(&VenueOrderId::from("V-EXT-004"));
    assert_eq!(resolved, Some(&ClientOrderId::from("settlement-001")));
}

#[rstest]
fn test_reconcile_order_status_report_external_order_skipped_without_instrument(
    mut execution_engine: ExecutionEngine,
) {
    let report = create_order_status_report(
        Some(ClientOrderId::from("autoclose-999")),
        VenueOrderId::from("V-EXT-999"),
        audusd_sim().id(),
        OrderStatus::Filled,
        Quantity::from(100_000),
        Quantity::from(100_000),
    );

    execution_engine.reconcile_order_status_report(&report);

    let cache = execution_engine.cache().borrow();
    assert!(!cache.order_exists(&ClientOrderId::from("autoclose-999")));
}

#[rstest]
fn test_reconcile_order_with_fills_creates_external_with_real_fill(
    mut execution_engine: ExecutionEngine,
) {
    let instrument = audusd_sim();
    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let client_order_id = ClientOrderId::from("adl_autoclose-001");
    let venue_order_id = VenueOrderId::from("V-BUNDLED-001");
    let trade_id = TradeId::from("T-REAL-001");

    let order_report = create_order_status_report(
        Some(client_order_id),
        venue_order_id,
        instrument.id(),
        OrderStatus::Filled,
        Quantity::from(100_000),
        Quantity::from(100_000),
    );

    let fill_report = create_fill_report(
        instrument.id(),
        Some(client_order_id),
        venue_order_id,
        trade_id,
        Quantity::from(100_000),
        Price::from("1.00000"),
    );

    execution_engine.reconcile_order_with_fills(&order_report, &[fill_report]);

    let cache = execution_engine.cache().borrow();
    let order = cache
        .order(&client_order_id)
        .expect("external order should be in cache");
    assert_eq!(order.status(), OrderStatus::Filled);
    // Real fill metadata is preserved instead of an inferred trade ID.
    assert_eq!(order.trade_ids().len(), 1);
    assert_eq!(*order.trade_ids()[0], trade_id);
}

#[rstest]
fn test_reconcile_order_with_fills_infers_residual_gap(mut execution_engine: ExecutionEngine) {
    let instrument = audusd_sim();
    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let client_order_id = ClientOrderId::from("adl_autoclose-002");
    let venue_order_id = VenueOrderId::from("V-BUNDLED-002");
    let real_trade_id = TradeId::from("T-REAL-002");

    let order_report = create_order_status_report(
        Some(client_order_id),
        venue_order_id,
        instrument.id(),
        OrderStatus::Filled,
        Quantity::from(100_000),
        Quantity::from(100_000),
    );

    // Real fill covers only 70k of the 100k filled_qty; the engine must infer
    // a 30k fill to bring the order to its venue-reported terminal state.
    let real_fill = create_fill_report(
        instrument.id(),
        Some(client_order_id),
        venue_order_id,
        real_trade_id,
        Quantity::from(70_000),
        Price::from("1.00000"),
    );

    execution_engine.reconcile_order_with_fills(&order_report, &[real_fill]);

    let cache = execution_engine.cache().borrow();
    let order = cache
        .order(&client_order_id)
        .expect("external order should be in cache");
    assert_eq!(order.status(), OrderStatus::Filled);
    assert_eq!(order.filled_qty(), Quantity::from(100_000));
    assert_eq!(order.trade_ids().len(), 2);
    assert!(order.trade_ids().iter().any(|id| **id == real_trade_id));
}

#[rstest]
fn test_reconcile_order_with_fills_applies_to_cached_order(mut execution_engine: ExecutionEngine) {
    let instrument = audusd_sim();
    let client_order_id = ClientOrderId::from("O-LOCAL-001");
    let venue_order_id = VenueOrderId::from("V-LOCAL-001");

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(InstrumentAny::CurrencyPair(instrument.clone()))
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Market)
        .instrument_id(instrument.id())
        .client_order_id(client_order_id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(order.clone(), None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let submitted = TestOrderEventStubs::submitted(&order, AccountId::test_default());
    execution_engine.process(&submitted);
    let accepted = TestOrderEventStubs::accepted(&order, AccountId::test_default(), venue_order_id);
    execution_engine.process(&accepted);

    let order_report = create_order_status_report(
        Some(client_order_id),
        venue_order_id,
        instrument.id(),
        OrderStatus::Filled,
        Quantity::from(100_000),
        Quantity::from(100_000),
    );
    let fill = create_fill_report(
        instrument.id(),
        Some(client_order_id),
        venue_order_id,
        TradeId::from("T-LOCAL-001"),
        Quantity::from(100_000),
        Price::from("1.00000"),
    );

    execution_engine.reconcile_order_with_fills(&order_report, &[fill]);

    let cache = execution_engine.cache().borrow();
    let order = cache.order(&client_order_id).unwrap();
    assert_eq!(order.status(), OrderStatus::Filled);
    assert_eq!(order.filled_qty(), Quantity::from(100_000));
    assert_eq!(order.trade_ids().len(), 1);
    assert_eq!(*order.trade_ids()[0], TradeId::from("T-LOCAL-001"));
}

#[rstest]
#[case(OrderStatus::Canceled)]
#[case(OrderStatus::Expired)]
fn test_reconcile_order_with_fills_emits_terminal_event_for_external(
    mut execution_engine: ExecutionEngine,
    #[case] terminal_status: OrderStatus,
) {
    let instrument = audusd_sim();
    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let client_order_id = ClientOrderId::from("autoclose-terminal-001");
    let venue_order_id = VenueOrderId::from("V-TERMINAL-001");

    let order_report = create_order_status_report(
        Some(client_order_id),
        venue_order_id,
        instrument.id(),
        terminal_status,
        Quantity::from(100_000),
        Quantity::from(0),
    );

    execution_engine.reconcile_order_with_fills(&order_report, &[]);

    let cache = execution_engine.cache().borrow();
    let order = cache
        .order(&client_order_id)
        .expect("external order should be in cache");
    assert_eq!(order.status(), terminal_status);
    assert!(order.is_closed());
    assert_eq!(order.filled_qty(), Quantity::from(0));
}

#[rstest]
fn test_reconcile_order_with_fills_applies_multiple_fills(mut execution_engine: ExecutionEngine) {
    let instrument = audusd_sim();
    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let client_order_id = ClientOrderId::from("adl_autoclose-multi");
    let venue_order_id = VenueOrderId::from("V-MULTI-001");
    let trade_id_a = TradeId::from("T-MULTI-A");
    let trade_id_b = TradeId::from("T-MULTI-B");

    let order_report = create_order_status_report(
        Some(client_order_id),
        venue_order_id,
        instrument.id(),
        OrderStatus::Filled,
        Quantity::from(100_000),
        Quantity::from(100_000),
    );

    let fill_a = create_fill_report(
        instrument.id(),
        Some(client_order_id),
        venue_order_id,
        trade_id_a,
        Quantity::from(30_000),
        Price::from("1.00000"),
    );
    let fill_b = create_fill_report(
        instrument.id(),
        Some(client_order_id),
        venue_order_id,
        trade_id_b,
        Quantity::from(70_000),
        Price::from("1.00000"),
    );

    execution_engine.reconcile_order_with_fills(&order_report, &[fill_a, fill_b]);

    let cache = execution_engine.cache().borrow();
    let order = cache
        .order(&client_order_id)
        .expect("external order should be in cache");
    assert_eq!(order.status(), OrderStatus::Filled);
    assert_eq!(order.filled_qty(), Quantity::from(100_000));
    // Both real trade IDs are preserved; no inferred fill is generated because
    // sum(real fills) == report.filled_qty.
    assert_eq!(order.trade_ids().len(), 2);
    assert!(order.trade_ids().iter().any(|id| **id == trade_id_a));
    assert!(order.trade_ids().iter().any(|id| **id == trade_id_b));
}

#[rstest]
fn test_reconcile_order_with_fills_empty_fills_infers_full_quantity(
    mut execution_engine: ExecutionEngine,
) {
    let instrument = audusd_sim();
    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let client_order_id = ClientOrderId::from("adl_autoclose-empty");
    let venue_order_id = VenueOrderId::from("V-EMPTY-001");

    let order_report = create_order_status_report(
        Some(client_order_id),
        venue_order_id,
        instrument.id(),
        OrderStatus::Filled,
        Quantity::from(100_000),
        Quantity::from(100_000),
    );

    execution_engine.reconcile_order_with_fills(&order_report, &[]);

    let cache = execution_engine.cache().borrow();
    let order = cache
        .order(&client_order_id)
        .expect("external order should be in cache");
    // With no real fills, the gap path infers a single fill for the entire
    // reported quantity so the order reaches its venue-reported terminal state.
    assert_eq!(order.status(), OrderStatus::Filled);
    assert_eq!(order.filled_qty(), Quantity::from(100_000));
    assert_eq!(order.trade_ids().len(), 1);
}

// Drives a future to completion without an executor. Suitable for futures that
// are `Ready` on first poll (e.g., `Cache::cache_all` with `database: None`).
fn poll_to_completion<F: Future>(fut: F) -> F::Output {
    let mut fut = pin!(fut);
    let waker = Waker::noop();
    let mut cx = Context::from_waker(waker);
    loop {
        if let Poll::Ready(out) = fut.as_mut().poll(&mut cx) {
            return out;
        }
    }
}

// Regression: the original `load_cache` panicked at the first nested
// `self.cache.borrow_mut().cache_all()` call before any later code could run.
// This test triggers that path and verifies the function now completes.
// Parameterized over `manage_own_order_books` so both config branches run.
//
// The second nested-borrow path (iterating `cache.orders(...)` while invoking
// `get_or_init_own_order_book`) is not exercised here: with `database: None`,
// `cache_all` clears `self.orders`, so the loop sees an empty cache. Locking
// down that path would need a stub `CacheDatabaseAdapter` that returns the
// staged order from `load_all`; deferred while `load_cache` has no callers.
#[rstest]
#[case::own_books_enabled(true)]
#[case::own_books_disabled(false)]
fn test_load_cache_no_reentrant_panic(#[case] manage_own_order_books: bool) {
    let clock = Rc::new(RefCell::new(TestClock::new()));
    let cache = Rc::new(RefCell::new(Cache::default()));
    let config = ExecutionEngineConfig {
        manage_own_order_books,
        ..Default::default()
    };
    let mut engine = ExecutionEngine::new(clock, cache, Some(config));

    let instrument = audusd_sim();
    engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();

    let order = OrderTestBuilder::new(OrderType::Limit)
        .trader_id(TraderId::test_default())
        .strategy_id(StrategyId::test_default())
        .instrument_id(instrument.id)
        .client_order_id(ClientOrderId::from("O-20240101-000000-001-001-1"))
        .side(OrderSide::Buy)
        .price(Price::from("1.00000"))
        .quantity(Quantity::from(100_000))
        .build();

    engine
        .cache()
        .borrow_mut()
        .add_order(order, None, None, true)
        .unwrap();

    poll_to_completion(engine.load_cache()).expect("load_cache should not panic");

    // With `database: None`, `cache_all` replaces all orders/positions with empty
    // maps, so the staged order is wiped and the own-book loop has nothing to
    // process. Verify the full flow ran end-to-end (the original bug
    // short-circuited before `cache_all` could clear) and the optional own-book
    // branch did not produce a book for this instrument.
    let cache = engine.cache().borrow();
    assert!(cache.orders(None, None, None, None, None).is_empty());
    assert!(cache.own_order_book(&instrument.id).is_none());
}

// Regression for #3981: a parent OTO fill linking `position_id` to a contingent
// child triggered nested `RefCell` borrows in `handle_order_fill`: the outer
// `cache.order_mut(...)` write handle was still alive when `add_position_id`
// took a fresh `borrow_mut` on the cache.
#[rstest]
fn test_handle_order_fill_oto_links_position_to_contingent_children(
    mut execution_engine: ExecutionEngine,
) {
    let trader_id = TraderId::test_default();
    let strategy_id = StrategyId::test_default();
    let account_id = AccountId::test_default();
    let instrument = audusd_sim();
    let parent_id = ClientOrderId::from("O-20240101-000000-001-001-1");
    let child_id = ClientOrderId::from("O-20240101-000000-001-001-2");

    let stub_client = StubExecutionClient::new(
        ClientId::from("STUB"),
        account_id,
        Venue::test_default(),
        OmsType::Netting,
        None,
    );
    execution_engine
        .register_client(Box::new(stub_client))
        .unwrap();

    execution_engine
        .cache()
        .borrow_mut()
        .add_instrument(instrument.clone().into())
        .unwrap();
    execution_engine
        .cache()
        .borrow_mut()
        .add_account(CashAccount::default().into())
        .unwrap();

    let parent_order = OrderTestBuilder::new(OrderType::Market)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(parent_id)
        .side(OrderSide::Buy)
        .quantity(Quantity::from(100_000))
        .contingency_type(ContingencyType::Oto)
        .linked_order_ids(vec![child_id])
        .build();

    let child_order = OrderTestBuilder::new(OrderType::StopMarket)
        .trader_id(trader_id)
        .strategy_id(strategy_id)
        .instrument_id(instrument.id)
        .client_order_id(child_id)
        .side(OrderSide::Sell)
        .quantity(Quantity::from(100_000))
        .trigger_price(Price::from("0.95"))
        .contingency_type(ContingencyType::Oto)
        .parent_order_id(parent_id)
        .build();

    execution_engine
        .cache()
        .borrow_mut()
        .add_order(
            parent_order.clone(),
            None,
            Some(ClientId::from("STUB")),
            true,
        )
        .unwrap();
    execution_engine
        .cache()
        .borrow_mut()
        .add_order(child_order, None, Some(ClientId::from("STUB")), true)
        .unwrap();

    let submitted = TestOrderEventStubs::submitted(&parent_order, account_id);
    execution_engine.process(&submitted);

    let filled = TestOrderEventStubs::filled(
        &parent_order,
        &instrument.into(),
        Some(TradeId::new("E-19700101-000000-001-001-0")),
        None,
        None,
        None,
        None,
        None,
        None,
        Some(account_id),
    );
    execution_engine.process(&filled);

    let cache = execution_engine.cache().borrow();
    let position_ids = cache.position_ids(None, None, None, None);
    assert_eq!(position_ids.len(), 1);
    let position_id = *position_ids.iter().next().unwrap();

    let cached_child = cache.order(&child_id).expect("child order in cache");
    assert_eq!(
        cached_child.position_id(),
        Some(position_id),
        "OTO child order must inherit the parent's position id",
    );
    assert_eq!(
        cache.position_id(&child_id),
        Some(&position_id),
        "Cache index must map the contingent child to the new position id",
    );
}