cdk 0.16.0-rc.2

//! Tests for melt saga pattern implementation
//!
//! This test module covers:
//! - Basic state transitions
//! - Crash recovery scenarios
//! - Saga persistence and deletion
//! - Compensation execution
//! - Concurrent operations
//! - Failure handling

use std::str::FromStr;

use cdk_common::mint::{MeltSagaState, OperationKind, Saga};
use cdk_common::nut00::KnownMethod;
use cdk_common::nuts::MeltQuoteState;
use cdk_common::{Amount, PaymentMethod, ProofsMethods, State};

use crate::mint::melt::melt_saga::MeltSaga;
use crate::test_helpers::mint::{create_test_mint, mint_test_proofs};

// ============================================================================
// Basic State Transition Tests
// ============================================================================

/// Test: Saga can be created in Initial state
#[tokio::test]
async fn test_melt_saga_initial_state_creation() {
    let mint = create_test_mint().await.unwrap();
    let db = mint.localstore();
    let pubsub = mint.pubsub_manager();

    let _saga = MeltSaga::new(std::sync::Arc::new(mint.clone()), db, pubsub);
    // Type system enforces Initial state - if this compiles, test passes
}

// ============================================================================
// Saga Persistence Tests
// ============================================================================

/// Test: Saga state is persisted atomically with setup transaction
#[tokio::test]
async fn test_saga_state_persistence_after_setup() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let melt_request = create_test_melt_request(&proofs, &quote);

    // STEP 2: Setup melt saga
    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    let operation_id = *setup_saga.state_data.operation.id();

    // STEP 3: Query database for saga
    let sagas = mint
        .localstore
        .get_incomplete_sagas(OperationKind::Melt)
        .await
        .unwrap();

    // STEP 4: Find our saga
    let persisted_saga = sagas
        .iter()
        .find(|s| s.operation_id == operation_id)
        .expect("Saga should be persisted");

    // STEP 5: Validate saga content
    assert_eq!(
        persisted_saga.operation_id, operation_id,
        "Operation ID should match"
    );
    assert_eq!(
        persisted_saga.operation_kind,
        OperationKind::Melt,
        "Operation kind should be Melt"
    );

    // Verify state is SetupComplete
    match &persisted_saga.state {
        cdk_common::mint::SagaStateEnum::Melt(state) => {
            assert_eq!(
                *state,
                MeltSagaState::SetupComplete,
                "State should be SetupComplete"
            );
        }
        _ => panic!("Expected Melt saga state"),
    }

    // STEP 6: Verify input_ys can be looked up by operation_id
    let input_ys = proofs.ys().unwrap();
    let stored_input_ys = mint
        .localstore
        .get_proof_ys_by_operation_id(&persisted_saga.operation_id)
        .await
        .unwrap();
    assert_eq!(
        stored_input_ys.len(),
        input_ys.len(),
        "Should store all input Ys"
    );
    for y in &input_ys {
        assert!(
            stored_input_ys.contains(y),
            "Input Y should be stored: {:?}",
            y
        );
    }

    // STEP 7: Verify timestamps are set
    assert!(
        persisted_saga.created_at > 0,
        "Created timestamp should be set"
    );
    assert!(
        persisted_saga.updated_at > 0,
        "Updated timestamp should be set"
    );
    assert_eq!(
        persisted_saga.created_at, persisted_saga.updated_at,
        "Timestamps should match for new saga"
    );

    // STEP 8: Verify blinded_secrets lookup returns empty (not used for melt without change)
    let stored_blinded_secrets = mint
        .localstore
        .get_blinded_secrets_by_operation_id(&persisted_saga.operation_id)
        .await
        .unwrap();
    assert!(
        stored_blinded_secrets.is_empty(),
        "Melt saga without change should have no blinded_secrets"
    );

    // SUCCESS: Saga persisted correctly!
}

/// Test: Saga is deleted after successful finalization
#[tokio::test]
async fn test_saga_deletion_on_success() {
    // STEP 1: Setup test environment (FakeWallet handles payments automatically)
    let mint = create_test_mint().await.unwrap();

    // STEP 2: Create proofs and quote
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let melt_request = create_test_melt_request(&proofs, &quote);

    // STEP 3: Complete full melt flow
    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );

    // Setup
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();
    let operation_id = *setup_saga.state_data.operation.id();

    // Verify saga exists
    assert_saga_exists(&mint, &operation_id).await;

    // Attempt internal settlement (will fail, go to external payment)
    let (payment_saga, decision) = setup_saga
        .attempt_internal_settlement(&melt_request)
        .await
        .unwrap();

    // Make payment (FakeWallet will return success based on FakeInvoiceDescription)
    let confirmed_saga = payment_saga.make_payment(decision).await.unwrap();

    // Finalize
    let _response = confirmed_saga.finalize().await.unwrap();

    // STEP 4: Verify saga was deleted
    assert_saga_not_exists(&mint, &operation_id).await;

    // STEP 5: Verify no incomplete sagas remain
    let sagas = mint
        .localstore
        .get_incomplete_sagas(OperationKind::Melt)
        .await
        .unwrap();
    assert!(sagas.is_empty(), "Should have no incomplete melt sagas");

    // SUCCESS: Saga cleaned up on success!
}

/// Test: Saga remains in database if finalize fails
#[tokio::test]
async fn test_saga_persists_on_finalize_failure() {
    // TODO: Implement this test
    // 1. Setup melt saga successfully
    // 2. Simulate finalize failure (e.g., database error)
    // 3. Verify saga still exists in database
    // 4. Verify state is still SetupComplete
}

// ============================================================================
// Crash Recovery Tests - SetupComplete State
// ============================================================================

/// Test: Recovery from crash after setup but before payment
///
/// This is the primary crash recovery scenario. If the mint crashes after
/// setup_melt() completes but before payment is sent, the proofs should be
/// restored on restart.
#[tokio::test]
async fn test_crash_recovery_setup_complete() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();

    // STEP 2: Create test proofs (10,000 millisats = 10 sats)
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let input_ys = proofs.ys().unwrap();

    // STEP 3: Create melt quote (9,000 millisats = 9 sats)
    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;

    // STEP 4: Create melt request
    let melt_request = create_test_melt_request(&proofs, &quote);

    // STEP 5: Setup melt saga (this persists saga to DB)
    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .expect("Setup should succeed");

    // STEP 6: Verify proofs are PENDING
    assert_proofs_state(&mint, &input_ys, Some(State::Pending)).await;

    // STEP 7: Verify saga was persisted
    let operation_id = *setup_saga.state_data.operation.id();
    assert_saga_exists(&mint, &operation_id).await;

    // STEP 8: Simulate crash - drop saga without finalizing
    drop(setup_saga);

    // STEP 9: Run recovery (simulating mint restart)
    mint.recover_from_incomplete_melt_sagas()
        .await
        .expect("Recovery should succeed");

    // STEP 10: Verify proofs were REMOVED (restored to client)
    assert_proofs_state(&mint, &input_ys, None).await;

    // STEP 11: Verify saga was deleted
    assert_saga_not_exists(&mint, &operation_id).await;

    // STEP 12: Verify quote state reset to UNPAID
    let recovered_quote = mint
        .localstore
        .get_melt_quote(&quote.id)
        .await
        .unwrap()
        .expect("Quote should still exist");
    assert_eq!(
        recovered_quote.state,
        MeltQuoteState::Unpaid,
        "Quote state should be reset to Unpaid after recovery"
    );

    // SUCCESS: Crash recovery works!
}

/// Test: Multiple incomplete sagas can be recovered
///
/// This test validates that the recovery mechanism can handle multiple
/// incomplete sagas in a single recovery pass, ensuring batch operations work.
#[tokio::test]
async fn test_crash_recovery_multiple_sagas() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();

    // STEP 2: Create multiple incomplete melt sagas (5 sagas)
    let mut operation_ids = Vec::new();
    let mut proof_ys_list = Vec::new();
    let mut quote_ids = Vec::new();

    for i in 0..5 {
        // Use smaller amounts to fit within FakeWallet limits
        let proofs = mint_test_proofs(&mint, Amount::from(5_000 + i * 100))
            .await
            .unwrap();
        let input_ys = proofs.ys().unwrap();
        let quote = create_test_melt_quote(&mint, Amount::from(4_000 + i * 100)).await;
        let melt_request = create_test_melt_request(&proofs, &quote);

        let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
        let saga = MeltSaga::new(
            std::sync::Arc::new(mint.clone()),
            mint.localstore(),
            mint.pubsub_manager(),
        );
        let setup_saga = saga
            .setup_melt(
                &melt_request,
                verification,
                PaymentMethod::Known(KnownMethod::Bolt11),
            )
            .await
            .unwrap();

        operation_ids.push(*setup_saga.state_data.operation.id());
        proof_ys_list.push(input_ys);
        quote_ids.push(quote.id.clone());

        // Drop saga to simulate crash
        drop(setup_saga);
    }

    // STEP 3: Verify all sagas exist before recovery
    let sagas_before = mint
        .localstore
        .get_incomplete_sagas(OperationKind::Melt)
        .await
        .unwrap();

    assert_eq!(
        sagas_before.len(),
        5,
        "Should have 5 incomplete sagas before recovery"
    );

    // Verify all our operation IDs are present
    for operation_id in &operation_ids {
        assert!(
            sagas_before.iter().any(|s| s.operation_id == *operation_id),
            "Saga {} should exist before recovery",
            operation_id
        );
    }

    // Verify all proofs are PENDING
    for input_ys in &proof_ys_list {
        assert_proofs_state(&mint, input_ys, Some(State::Pending)).await;
    }

    // STEP 4: Run recovery (should handle all sagas)
    mint.recover_from_incomplete_melt_sagas()
        .await
        .expect("Recovery should succeed");

    // STEP 5: Verify all sagas were recovered and cleaned up
    let sagas_after = mint
        .localstore
        .get_incomplete_sagas(OperationKind::Melt)
        .await
        .unwrap();

    assert!(
        sagas_after.is_empty(),
        "All sagas should be deleted after recovery"
    );

    // Verify none of our operation IDs exist
    for operation_id in &operation_ids {
        assert_saga_not_exists(&mint, operation_id).await;
    }

    // STEP 6: Verify all proofs were removed (returned to client)
    for input_ys in &proof_ys_list {
        assert_proofs_state(&mint, input_ys, None).await;
    }

    // STEP 7: Verify all quotes were reset to UNPAID
    for quote_id in &quote_ids {
        let recovered_quote = mint
            .localstore
            .get_melt_quote(quote_id)
            .await
            .unwrap()
            .expect("Quote should still exist");

        assert_eq!(
            recovered_quote.state,
            MeltQuoteState::Unpaid,
            "Quote {} should be reset to Unpaid",
            quote_id
        );
    }

    // SUCCESS: Multiple sagas recovered successfully!
}

/// Test: Recovery handles sagas gracefully even when data relationships exist
///
/// This test verifies that recovery works correctly in a standard crash scenario
/// where all data is intact (saga, quote, proofs all exist).
#[tokio::test]
async fn test_crash_recovery_orphaned_saga() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let melt_request = create_test_melt_request(&proofs, &quote);

    // STEP 2: Create incomplete saga
    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    let operation_id = *setup_saga.state_data.operation.id();
    let input_ys = proofs.ys().unwrap();

    // Drop saga (simulate crash)
    drop(setup_saga);

    // Verify saga exists
    assert_saga_exists(&mint, &operation_id).await;
    assert_proofs_state(&mint, &input_ys, Some(State::Pending)).await;

    // STEP 3: Run recovery
    // Recovery should handle the saga gracefully, cleaning up all state
    mint.recover_from_incomplete_melt_sagas()
        .await
        .expect("Recovery should succeed");

    // STEP 4: Verify saga was cleaned up
    assert_saga_not_exists(&mint, &operation_id).await;
    assert_proofs_state(&mint, &input_ys, None).await;

    // Verify quote was reset
    let recovered_quote = mint
        .localstore
        .get_melt_quote(&quote.id)
        .await
        .unwrap()
        .unwrap();
    assert_eq!(recovered_quote.state, MeltQuoteState::Unpaid);

    // SUCCESS: Recovery works correctly!
}

/// Test: Recovery continues even if one saga fails
#[tokio::test]
async fn test_crash_recovery_partial_failure() {
    // TODO: Implement this test
    // 1. Create multiple incomplete sagas
    // 2. Make one saga fail (e.g., corrupted data)
    // 3. Run recovery
    // 4. Verify other sagas were still recovered
    // 5. Verify failed saga is logged but doesn't stop recovery
}

/// Test: Crash recovery after internal settlement commits but before finalize
///
/// This test verifies that if the mint crashes after internal settlement
/// (melt-to-mint on same mint) commits but before finalize() completes,
/// recovery will correctly finalize the melt rather than compensating.
///
/// This prevents fund loss where:
/// - The mint quote was credited (mint received funds)
/// - But proofs are returned to user (double-spend)
#[tokio::test]
async fn test_crash_recovery_internal_settlement() {
    use cdk_common::nuts::MintQuoteState;
    use cdk_common::MintQuoteBolt11Request;

    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let input_ys = proofs.ys().unwrap();

    // STEP 2: Create a mint quote that will be paid internally
    // This creates a payment request (invoice) on this mint
    // Note: We use a smaller amount (4000) because the test mint has 100% fee reserve,
    // so required = amount + fee_reserve = 4000 + 4000 = 8000 < 10000 inputs
    let mint_quote_response: cdk_common::MintQuoteBolt11Response<_> = mint
        .get_mint_quote(
            MintQuoteBolt11Request {
                amount: Amount::from(4_000),
                unit: cdk_common::CurrencyUnit::Sat,
                description: None,
                pubkey: None,
            }
            .into(),
        )
        .await
        .unwrap()
        .into();

    // Get the mint quote from database
    let mint_quote_id = cdk_common::QuoteId::from_str(&mint_quote_response.quote).unwrap();
    let mint_quote = mint
        .localstore
        .get_mint_quote(&mint_quote_id)
        .await
        .unwrap()
        .expect("Mint quote should exist");

    // STEP 3: Create a melt quote that uses the mint quote's payment request
    // This will trigger internal settlement since it's the same mint
    use cdk_common::melt::MeltQuoteRequest;
    use cdk_common::nuts::MeltQuoteBolt11Request;

    let melt_bolt11_request = MeltQuoteBolt11Request {
        request: mint_quote.request.to_string().parse().unwrap(),
        unit: cdk_common::CurrencyUnit::Sat,
        options: None,
    };
    let melt_quote_request = MeltQuoteRequest::Bolt11(melt_bolt11_request);

    let melt_quote_response = mint.get_melt_quote(melt_quote_request).await.unwrap();
    let melt_quote = mint
        .localstore
        .get_melt_quote(&melt_quote_response.quote)
        .await
        .unwrap()
        .expect("Melt quote should exist");

    // STEP 4: Create melt request and setup saga
    let melt_request = create_test_melt_request(&proofs, &melt_quote);
    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();

    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );

    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();
    let operation_id = *setup_saga.state_data.operation.id();

    // STEP 5: Attempt internal settlement - this will commit and update saga state
    let (payment_saga, decision) = setup_saga
        .attempt_internal_settlement(&melt_request)
        .await
        .unwrap();

    // Verify internal settlement was detected
    match decision {
        crate::mint::melt::melt_saga::state::SettlementDecision::Internal { amount } => {
            assert_eq!(
                amount,
                Amount::from(4_000).with_unit(cdk_common::CurrencyUnit::Sat),
                "Internal settlement amount should match"
            );
        }
        _ => panic!("Expected internal settlement decision"),
    }

    // STEP 6: Simulate crash - drop saga WITHOUT calling make_payment/finalize
    drop(payment_saga);

    // STEP 7: Verify pre-recovery state
    // Saga should exist in PaymentAttempted state (updated by internal settlement)
    let persisted_saga = assert_saga_exists(&mint, &operation_id).await;
    match &persisted_saga.state {
        cdk_common::mint::SagaStateEnum::Melt(state) => {
            assert_eq!(
                *state,
                MeltSagaState::PaymentAttempted,
                "Saga should be in PaymentAttempted state after internal settlement"
            );
        }
        _ => panic!("Expected Melt saga state"),
    }

    // Proofs should still be Pending
    assert_proofs_state(&mint, &input_ys, Some(State::Pending)).await;

    // Mint quote should be paid (internal settlement committed)
    let mint_quote_after = mint
        .localstore
        .get_mint_quote(&mint_quote_id)
        .await
        .unwrap()
        .expect("Mint quote should exist");
    assert_eq!(
        mint_quote_after.state(),
        MintQuoteState::Paid,
        "Mint quote should be paid after internal settlement"
    );

    // STEP 8: Run recovery
    mint.recover_from_incomplete_melt_sagas()
        .await
        .expect("Recovery should succeed");

    // STEP 9: Verify post-recovery state
    // Saga should be deleted (successfully finalized)
    assert_saga_not_exists(&mint, &operation_id).await;

    // CRITICAL: Proofs should be SPENT, not returned (None)
    // This is the key assertion - if proofs were compensated, they'd be None
    assert_proofs_state(&mint, &input_ys, Some(State::Spent)).await;

    // Melt quote should be Paid
    let melt_quote_after = mint
        .localstore
        .get_melt_quote(&melt_quote.id)
        .await
        .unwrap()
        .expect("Melt quote should exist");
    assert_eq!(
        melt_quote_after.state,
        MeltQuoteState::Paid,
        "Melt quote should be paid after recovery"
    );

    // Mint quote should still be paid
    let mint_quote_final = mint
        .localstore
        .get_mint_quote(&mint_quote_id)
        .await
        .unwrap()
        .expect("Mint quote should exist");
    assert_eq!(
        mint_quote_final.state(),
        MintQuoteState::Paid,
        "Mint quote should remain paid after recovery"
    );

    // SUCCESS: Recovery correctly finalized internal settlement!
    // No fund loss - proofs spent and mint quote paid
}

// ============================================================================
// Startup Integration Tests
// ============================================================================

/// Test: Startup recovery is called on mint.start()
#[tokio::test]
async fn test_startup_recovery_integration() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();

    // STEP 2: Create incomplete saga
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let melt_request = create_test_melt_request(&proofs, &quote);

    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    let operation_id = *setup_saga.state_data.operation.id();
    let input_ys = proofs.ys().unwrap();

    // Drop saga (simulate crash)
    drop(setup_saga);

    // Verify saga exists after setup
    assert_saga_exists(&mint, &operation_id).await;
    assert_proofs_state(&mint, &input_ys, Some(State::Pending)).await;

    // STEP 3: Manually trigger recovery (simulating restart behavior)
    // Note: create_test_mint() already calls mint.start(), so recovery should
    // have run on startup. However, since we created the saga AFTER startup,
    // we need to manually trigger recovery to simulate a restart scenario.
    mint.recover_from_incomplete_melt_sagas()
        .await
        .expect("Recovery should succeed");

    // STEP 4: Verify recovery was executed
    assert_saga_not_exists(&mint, &operation_id).await;
    assert_proofs_state(&mint, &input_ys, None).await;

    // STEP 5: Verify mint is running normally
    // (Can perform new melt operations)
    let new_proofs = mint_test_proofs(&mint, Amount::from(5_000)).await.unwrap();
    let new_quote = create_test_melt_quote(&mint, Amount::from(4_000)).await;
    let new_request = create_test_melt_request(&new_proofs, &new_quote);

    let new_verification = mint.verify_inputs(new_request.inputs()).await.unwrap();
    let new_saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let _new_setup = new_saga
        .setup_melt(
            &new_request,
            new_verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    // SUCCESS: Recovery runs on startup and mint works normally!
}

/// Test: Startup never fails due to recovery errors
#[tokio::test]
async fn test_startup_resilient_to_recovery_errors() {
    // TODO: Implement this test
    // 1. Create corrupted saga data
    // 2. Call mint.start()
    // 3. Verify start() completes successfully
    // 4. Verify error was logged
}

// ============================================================================
// Compensation Tests
// ============================================================================

/// Test: Compensation removes proofs from database
///
/// This test validates that when compensation runs (during crash recovery),
/// the proofs are properly removed from the database and returned to the client.
#[tokio::test]
async fn test_compensation_removes_proofs() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let input_ys = proofs.ys().unwrap();
    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let melt_request = create_test_melt_request(&proofs, &quote);

    // STEP 2: Setup melt saga (this marks proofs as PENDING)
    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    let operation_id = *setup_saga.state_data.operation.id();

    // Verify proofs are PENDING
    assert_proofs_state(&mint, &input_ys, Some(State::Pending)).await;

    // STEP 3: Simulate crash and trigger compensation via recovery
    drop(setup_saga);

    // Run recovery which triggers compensation
    mint.recover_from_incomplete_melt_sagas()
        .await
        .expect("Recovery should succeed");

    // STEP 4: Verify proofs were removed from database (returned to client)
    assert_proofs_state(&mint, &input_ys, None).await;

    // STEP 5: Verify saga was cleaned up
    assert_saga_not_exists(&mint, &operation_id).await;

    // STEP 6: Verify proofs can be used again in a new melt operation
    let new_quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let new_request = create_test_melt_request(&proofs, &new_quote);

    let new_verification = mint.verify_inputs(new_request.inputs()).await.unwrap();
    let new_saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let new_setup = new_saga
        .setup_melt(
            &new_request,
            new_verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .expect("Should be able to reuse proofs after compensation");

    // Verify new saga was created successfully
    assert_saga_exists(&mint, new_setup.state_data.operation.id()).await;

    // SUCCESS: Compensation properly removed proofs and they can be reused!
}

/// Test: Compensation removes change outputs
///
/// This test validates that compensation properly removes blinded messages
/// (change outputs) from the database during rollback.
#[tokio::test]
async fn test_compensation_removes_change_outputs() {
    use cdk_common::nuts::MeltRequest;

    use crate::test_helpers::mint::create_test_blinded_messages;

    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();

    // Create input proofs (more than needed so we have change)
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let quote = create_test_melt_quote(&mint, Amount::from(7_000)).await;

    // STEP 2: Create change outputs (blinded messages)
    // Change = 10,000 - 7,000 - fee = ~3,000 sats
    let (blinded_messages, _premint) = create_test_blinded_messages(&mint, Amount::from(3_000))
        .await
        .unwrap();

    let blinded_secrets: Vec<_> = blinded_messages
        .iter()
        .map(|bm| bm.blinded_secret)
        .collect();

    // STEP 3: Create melt request with change outputs
    let melt_request = MeltRequest::new(quote.id.clone(), proofs.clone(), Some(blinded_messages));

    // STEP 4: Setup melt saga (this stores blinded messages)
    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    let operation_id = *setup_saga.state_data.operation.id();

    // STEP 5: Verify blinded messages are stored in database
    let stored_info = {
        let mut tx = mint.localstore.begin_transaction().await.unwrap();
        let info = tx
            .get_melt_request_and_blinded_messages(&quote.id)
            .await
            .expect("Should be able to query melt request")
            .expect("Melt request should exist");
        tx.rollback().await.unwrap();
        info
    };

    assert_eq!(
        stored_info.change_outputs.len(),
        blinded_secrets.len(),
        "All blinded messages should be stored"
    );

    // STEP 6: Simulate crash and trigger compensation
    drop(setup_saga);

    mint.recover_from_incomplete_melt_sagas()
        .await
        .expect("Recovery should succeed");

    // STEP 7: Verify blinded messages were removed
    let result = {
        let mut tx = mint.localstore.begin_transaction().await.unwrap();
        let res = tx
            .get_melt_request_and_blinded_messages(&quote.id)
            .await
            .expect("Query should succeed");
        tx.rollback().await.unwrap();
        res
    };

    assert!(
        result.is_none(),
        "Melt request and blinded messages should be deleted after compensation"
    );

    // STEP 8: Verify saga was cleaned up
    assert_saga_not_exists(&mint, &operation_id).await;

    // SUCCESS: Compensation properly removed change outputs!
}

/// Test: Compensation resets quote state
///
/// This test validates that compensation properly resets the quote state
/// from PENDING back to UNPAID, allowing the quote to be used again.
#[tokio::test]
async fn test_compensation_resets_quote_state() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;

    // Verify initial quote state is UNPAID
    assert_eq!(
        quote.state,
        MeltQuoteState::Unpaid,
        "Quote should start as Unpaid"
    );

    let melt_request = create_test_melt_request(&proofs, &quote);

    // STEP 2: Setup melt saga (this changes quote state to PENDING)
    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    let operation_id = *setup_saga.state_data.operation.id();

    // STEP 3: Verify quote state became PENDING
    let pending_quote = mint
        .localstore
        .get_melt_quote(&quote.id)
        .await
        .unwrap()
        .expect("Quote should exist");

    assert_eq!(
        pending_quote.state,
        MeltQuoteState::Pending,
        "Quote state should be Pending after setup"
    );

    // STEP 4: Simulate crash and trigger compensation
    drop(setup_saga);

    mint.recover_from_incomplete_melt_sagas()
        .await
        .expect("Recovery should succeed");

    // STEP 5: Verify quote state was reset to UNPAID
    let recovered_quote = mint
        .localstore
        .get_melt_quote(&quote.id)
        .await
        .unwrap()
        .expect("Quote should still exist after compensation");

    assert_eq!(
        recovered_quote.state,
        MeltQuoteState::Unpaid,
        "Quote state should be reset to Unpaid after compensation"
    );

    // STEP 6: Verify saga was cleaned up
    assert_saga_not_exists(&mint, &operation_id).await;

    // STEP 7: Verify quote can be used again with new melt request
    let new_proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let new_request = create_test_melt_request(&new_proofs, &recovered_quote);

    let new_verification = mint.verify_inputs(new_request.inputs()).await.unwrap();
    let new_saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let _new_setup = new_saga
        .setup_melt(
            &new_request,
            new_verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .expect("Should be able to reuse quote after compensation");

    // SUCCESS: Quote state properly reset and can be reused!
}

/// Test: Compensation is idempotent
///
/// This test validates that running compensation multiple times is safe
/// and produces consistent results. This is important because recovery
/// might be called multiple times during debugging or startup.
#[tokio::test]
async fn test_compensation_idempotent() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let input_ys = proofs.ys().unwrap();
    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let melt_request = create_test_melt_request(&proofs, &quote);

    // STEP 2: Setup melt saga
    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    let operation_id = *setup_saga.state_data.operation.id();

    // Verify initial state
    assert_proofs_state(&mint, &input_ys, Some(State::Pending)).await;
    assert_saga_exists(&mint, &operation_id).await;

    // STEP 3: Simulate crash
    drop(setup_saga);

    // STEP 4: Run compensation first time
    mint.recover_from_incomplete_melt_sagas()
        .await
        .expect("First recovery should succeed");

    // Verify state after first compensation
    assert_proofs_state(&mint, &input_ys, None).await;
    assert_saga_not_exists(&mint, &operation_id).await;

    let quote_after_first = mint
        .localstore
        .get_melt_quote(&quote.id)
        .await
        .unwrap()
        .expect("Quote should exist");
    assert_eq!(quote_after_first.state, MeltQuoteState::Unpaid);

    // STEP 5: Run compensation second time (should be idempotent)
    mint.recover_from_incomplete_melt_sagas()
        .await
        .expect("Second recovery should succeed without errors");

    // STEP 6: Verify state is unchanged after second compensation
    assert_proofs_state(&mint, &input_ys, None).await;
    assert_saga_not_exists(&mint, &operation_id).await;

    let quote_after_second = mint
        .localstore
        .get_melt_quote(&quote.id)
        .await
        .unwrap()
        .expect("Quote should still exist");
    assert_eq!(quote_after_second.state, MeltQuoteState::Unpaid);

    // STEP 7: Verify both results are identical
    assert_eq!(
        quote_after_first.state, quote_after_second.state,
        "Quote state should be identical after multiple compensations"
    );

    // STEP 8: Run third time to be extra sure
    mint.recover_from_incomplete_melt_sagas()
        .await
        .expect("Third recovery should also succeed");

    // SUCCESS: Compensation is idempotent and safe to run multiple times!
}

/// Test: Saga is deleted after direct payment failure (not via recovery)
///
/// This test validates that when make_payment() fails and compensate_all()
/// is called directly during normal operation (not through crash recovery),
/// the saga is properly deleted from the database.
///
/// This is different from the recovery tests which simulate crashes - this
/// tests the actual payment failure path in normal operation.
#[tokio::test]
async fn test_saga_deleted_after_payment_failure() {
    use cdk_common::CurrencyUnit;
    use cdk_fake_wallet::{create_fake_invoice, FakeInvoiceDescription};

    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let input_ys = proofs.ys().unwrap();

    // STEP 2: Create a quote that will FAIL payment
    let fake_description = FakeInvoiceDescription {
        pay_invoice_state: MeltQuoteState::Failed, // Payment will fail
        check_payment_state: MeltQuoteState::Failed, // Check will also show failed
        pay_err: false,
        check_err: false,
    };

    let amount_msats: u64 = Amount::from(9_000).into();
    let invoice = create_fake_invoice(
        amount_msats,
        serde_json::to_string(&fake_description).unwrap(),
    );

    let bolt11_request = cdk_common::nuts::MeltQuoteBolt11Request {
        request: invoice,
        unit: CurrencyUnit::Sat,
        options: None,
    };

    let request = cdk_common::melt::MeltQuoteRequest::Bolt11(bolt11_request);
    let quote_response = mint.get_melt_quote(request).await.unwrap();
    let quote = mint
        .localstore
        .get_melt_quote(&quote_response.quote)
        .await
        .unwrap()
        .expect("Quote should exist");

    let melt_request = create_test_melt_request(&proofs, &quote);

    // STEP 3: Setup melt saga
    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();
    let operation_id = setup_saga.operation_id;

    // Verify saga exists after setup
    assert_saga_exists(&mint, &operation_id).await;
    assert_proofs_state(&mint, &input_ys, Some(State::Pending)).await;

    // STEP 4: Attempt internal settlement (will return RequiresExternalPayment)
    let (payment_saga, decision) = setup_saga
        .attempt_internal_settlement(&melt_request)
        .await
        .unwrap();

    // STEP 5: Make payment - this should FAIL and trigger compensate_all()
    let result = payment_saga.make_payment(decision).await;

    // Payment should fail
    assert!(
        result.is_err(),
        "Payment should fail with Failed status from FakeWallet"
    );

    // STEP 6: Verify saga was deleted after compensation
    // This is the key assertion - the saga should be cleaned up after compensate_all()
    assert_saga_not_exists(&mint, &operation_id).await;

    // STEP 7: Verify proofs were returned (removed from database)
    assert_proofs_state(&mint, &input_ys, None).await;

    // STEP 8: Verify quote state was reset to Unpaid
    let recovered_quote = mint
        .localstore
        .get_melt_quote(&quote.id)
        .await
        .unwrap()
        .expect("Quote should still exist");
    assert_eq!(
        recovered_quote.state,
        MeltQuoteState::Unpaid,
        "Quote state should be reset to Unpaid after compensation"
    );

    // SUCCESS: Saga properly deleted after direct payment failure!
}

// ============================================================================
// Saga Content Validation Tests
// ============================================================================

/// Test: Persisted saga contains correct data
///
/// This test validates that all saga fields are persisted correctly,
/// providing comprehensive validation beyond the basic persistence test.
#[tokio::test]
async fn test_saga_content_validation() {
    // STEP 1: Setup test environment with known data
    let mint = create_test_mint().await.unwrap();

    // Create proofs with specific amount
    let proof_amount = Amount::from(10_000);
    let proofs = mint_test_proofs(&mint, proof_amount).await.unwrap();
    let input_ys = proofs.ys().unwrap();

    // Create quote with specific amount
    let quote_amount = Amount::from(9_000);
    let quote = create_test_melt_quote(&mint, quote_amount).await;

    // Create melt request
    let melt_request = create_test_melt_request(&proofs, &quote);

    // STEP 2: Setup melt saga
    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    let operation_id = *setup_saga.state_data.operation.id();

    // STEP 3: Retrieve saga from database
    let persisted_saga = assert_saga_exists(&mint, &operation_id).await;

    // STEP 4: Verify operation_id matches exactly
    assert_eq!(
        persisted_saga.operation_id, operation_id,
        "Operation ID should match exactly"
    );

    // STEP 5: Verify operation_kind is Melt
    assert_eq!(
        persisted_saga.operation_kind,
        OperationKind::Melt,
        "Operation kind must be Melt"
    );

    // STEP 6: Verify state is SetupComplete
    match &persisted_saga.state {
        cdk_common::mint::SagaStateEnum::Melt(state) => {
            assert_eq!(
                *state,
                MeltSagaState::SetupComplete,
                "State should be SetupComplete after setup"
            );
        }
        _ => panic!("Expected Melt saga state, got {:?}", persisted_saga.state),
    }

    // STEP 7: Verify input_ys can be looked up by operation_id
    let stored_input_ys = mint
        .localstore
        .get_proof_ys_by_operation_id(&persisted_saga.operation_id)
        .await
        .unwrap();
    assert_eq!(
        stored_input_ys.len(),
        input_ys.len(),
        "Should store all input Ys"
    );

    // Verify each Y is present
    for (i, expected_y) in input_ys.iter().enumerate() {
        assert!(
            stored_input_ys.contains(expected_y),
            "Input Y at index {} should be stored: {:?}",
            i,
            expected_y
        );
    }

    // STEP 8: Verify timestamps are set and reasonable
    let current_timestamp = web_time::SystemTime::now()
        .duration_since(web_time::UNIX_EPOCH)
        .unwrap()
        .as_secs();

    assert!(
        persisted_saga.created_at > 0,
        "Created timestamp should be set"
    );
    assert!(
        persisted_saga.updated_at > 0,
        "Updated timestamp should be set"
    );

    // Timestamps should be recent (within last hour)
    assert!(
        persisted_saga.created_at <= current_timestamp,
        "Created timestamp should not be in the future"
    );
    assert!(
        persisted_saga.created_at > current_timestamp - 3600,
        "Created timestamp should be recent (within last hour)"
    );

    // For new saga, created_at and updated_at should match
    assert_eq!(
        persisted_saga.created_at, persisted_saga.updated_at,
        "Timestamps should match for newly created saga"
    );

    // STEP 9: Verify blinded_secrets lookup returns empty (not used for melt without change)
    let stored_blinded_secrets = mint
        .localstore
        .get_blinded_secrets_by_operation_id(&persisted_saga.operation_id)
        .await
        .unwrap();
    assert!(
        stored_blinded_secrets.is_empty(),
        "Melt saga without change should have no blinded_secrets"
    );

    // SUCCESS: All saga content validated!
}

/// Test: Saga timestamps remain consistent across retrievals
///
/// Note: The melt saga doesn't have intermediate state updates that persist
/// to the database. It's created in SetupComplete state and then deleted on
/// finalize. This test validates that timestamps remain consistent when
/// retrieving the saga multiple times from the database.
#[tokio::test]
async fn test_saga_state_updates_timestamp() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let melt_request = create_test_melt_request(&proofs, &quote);

    // STEP 2: Setup melt saga and note timestamps
    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    let operation_id = *setup_saga.state_data.operation.id();

    // STEP 3: Retrieve saga and note timestamps
    let saga1 = assert_saga_exists(&mint, &operation_id).await;
    let created_at_1 = saga1.created_at;
    let updated_at_1 = saga1.updated_at;

    // STEP 4: Wait a brief moment
    tokio::time::sleep(tokio::time::Duration::from_millis(10)).await;

    // STEP 5: Retrieve saga again
    let saga2 = assert_saga_exists(&mint, &operation_id).await;
    let created_at_2 = saga2.created_at;
    let updated_at_2 = saga2.updated_at;

    // STEP 6: Verify timestamps remain unchanged across retrievals
    assert_eq!(
        created_at_1, created_at_2,
        "Created timestamp should not change across retrievals"
    );
    assert_eq!(
        updated_at_1, updated_at_2,
        "Updated timestamp should not change across retrievals"
    );

    // STEP 7: Verify timestamps are identical for new saga
    assert_eq!(
        created_at_1, updated_at_1,
        "New saga should have matching created_at and updated_at"
    );

    // SUCCESS: Timestamps are consistent!
}

// ============================================================================
// Query Tests
// ============================================================================

/// Test: get_incomplete_sagas returns only melt sagas
///
/// This test validates that the database query correctly filters sagas
/// by operation kind, only returning melt sagas when requested.
#[tokio::test]
async fn test_get_incomplete_sagas_filters_by_kind() {
    use crate::mint::swap::swap_saga::SwapSaga;
    use crate::test_helpers::mint::create_test_blinded_messages;

    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();

    // STEP 2: Create a melt saga
    let melt_proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let melt_quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let melt_request = create_test_melt_request(&melt_proofs, &melt_quote);

    let melt_verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let melt_saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let melt_setup = melt_saga
        .setup_melt(
            &melt_request,
            melt_verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    let melt_operation_id = *melt_setup.state_data.operation.id();

    // STEP 3: Create a swap saga
    let swap_proofs = mint_test_proofs(&mint, Amount::from(5_000)).await.unwrap();
    let swap_verification = crate::mint::Verification {
        amount: Amount::from(5_000).with_unit(cdk_common::nuts::CurrencyUnit::Sat),
    };

    let (swap_outputs, _) = create_test_blinded_messages(&mint, Amount::from(5_000))
        .await
        .unwrap();

    let swap_saga = SwapSaga::new(&mint, mint.localstore(), mint.pubsub_manager());
    let _swap_setup = swap_saga
        .setup_swap(&swap_proofs, &swap_outputs, None, swap_verification)
        .await
        .unwrap();

    // STEP 4: Query for incomplete melt sagas
    let melt_sagas = mint
        .localstore
        .get_incomplete_sagas(OperationKind::Melt)
        .await
        .unwrap();

    // STEP 5: Verify only melt saga is returned
    assert_eq!(melt_sagas.len(), 1, "Should return exactly one melt saga");

    assert_eq!(
        melt_sagas[0].operation_id, melt_operation_id,
        "Returned saga should be the melt saga"
    );

    assert_eq!(
        melt_sagas[0].operation_kind,
        OperationKind::Melt,
        "Returned saga should have Melt kind"
    );

    // STEP 6: Query for incomplete swap sagas
    let swap_sagas = mint
        .localstore
        .get_incomplete_sagas(OperationKind::Swap)
        .await
        .unwrap();

    // STEP 7: Verify only swap saga is returned
    assert_eq!(swap_sagas.len(), 1, "Should return exactly one swap saga");

    assert_eq!(
        swap_sagas[0].operation_kind,
        OperationKind::Swap,
        "Returned saga should have Swap kind"
    );

    // SUCCESS: Query correctly filters by operation kind!
}

/// Test: get_incomplete_sagas returns empty when none exist
#[tokio::test]
async fn test_get_incomplete_sagas_empty() {
    let mint = create_test_mint().await.unwrap();

    let sagas = mint
        .localstore
        .get_incomplete_sagas(OperationKind::Melt)
        .await
        .unwrap();

    assert!(sagas.is_empty(), "Should have no incomplete melt sagas");
}

// ============================================================================
// Concurrent Operation Tests
// ============================================================================

/// Test: Multiple concurrent melt operations don't interfere
#[tokio::test]
async fn test_concurrent_melt_operations() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();

    // STEP 2: Create 5 sets of proofs and quotes concurrently
    // Using same amount for each to avoid FakeWallet limit issues
    let mut tasks = Vec::new();

    for _ in 0..5 {
        let mint_clone = mint.clone();
        let task = tokio::spawn(async move {
            let proofs = mint_test_proofs(&mint_clone, Amount::from(10_000))
                .await
                .unwrap();
            let quote = create_test_melt_quote(&mint_clone, Amount::from(9_000)).await;
            (proofs, quote)
        });
        tasks.push(task);
    }

    let proof_quote_pairs: Vec<_> = futures::future::join_all(tasks)
        .await
        .into_iter()
        .map(|r| r.unwrap())
        .collect();

    // STEP 3: Setup all melt sagas concurrently
    let mut setup_tasks = Vec::new();

    for (proofs, quote) in proof_quote_pairs {
        let mint_clone = mint.clone();
        let task = tokio::spawn(async move {
            let melt_request = create_test_melt_request(&proofs, &quote);
            let verification = mint_clone
                .verify_inputs(melt_request.inputs())
                .await
                .unwrap();
            let saga = MeltSaga::new(
                std::sync::Arc::new(mint_clone.clone()),
                mint_clone.localstore(),
                mint_clone.pubsub_manager(),
            );
            let setup_saga = saga
                .setup_melt(
                    &melt_request,
                    verification,
                    PaymentMethod::Known(KnownMethod::Bolt11),
                )
                .await
                .unwrap();
            let operation_id = *setup_saga.state_data.operation.id();
            // Drop setup_saga before returning to avoid lifetime issues
            drop(setup_saga);
            operation_id
        });
        setup_tasks.push(task);
    }

    let operation_ids: Vec<_> = futures::future::join_all(setup_tasks)
        .await
        .into_iter()
        .map(|r| r.unwrap())
        .collect();

    // STEP 4: Verify all operation_ids are unique
    let unique_ids: std::collections::HashSet<_> = operation_ids.iter().collect();
    assert_eq!(
        unique_ids.len(),
        operation_ids.len(),
        "All operation IDs should be unique"
    );

    // STEP 5: Verify all sagas exist in database
    let sagas = mint
        .localstore
        .get_incomplete_sagas(OperationKind::Melt)
        .await
        .unwrap();
    assert!(sagas.len() >= 5, "Should have at least 5 incomplete sagas");

    for operation_id in &operation_ids {
        assert!(
            sagas.iter().any(|s| s.operation_id == *operation_id),
            "Saga {} should exist in database",
            operation_id
        );
    }

    // SUCCESS: Concurrent operations work without interference!
}

/// Test: Concurrent recovery and new operations work together
#[tokio::test]
async fn test_concurrent_recovery_and_operations() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();

    // STEP 2: Create incomplete saga
    let proofs1 = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let quote1 = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let melt_request1 = create_test_melt_request(&proofs1, &quote1);

    let verification1 = mint.verify_inputs(melt_request1.inputs()).await.unwrap();
    let saga1 = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga1 = saga1
        .setup_melt(
            &melt_request1,
            verification1,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();
    let incomplete_operation_id = *setup_saga1.state_data.operation.id();

    // Drop saga to simulate crash
    drop(setup_saga1);

    // Verify saga exists
    assert_saga_exists(&mint, &incomplete_operation_id).await;

    // STEP 3: Create tasks for concurrent recovery and new operation
    let mint_for_recovery = mint.clone();
    let recovery_task = tokio::spawn(async move {
        mint_for_recovery
            .recover_from_incomplete_melt_sagas()
            .await
            .expect("Recovery should succeed")
    });

    let mint_for_new_op = mint.clone();
    let new_operation_task = tokio::spawn(async move {
        let proofs2 = mint_test_proofs(&mint_for_new_op, Amount::from(10_000))
            .await
            .unwrap();
        let quote2 = create_test_melt_quote(&mint_for_new_op, Amount::from(9_000)).await;
        let melt_request2 = create_test_melt_request(&proofs2, &quote2);

        let verification2 = mint_for_new_op
            .verify_inputs(melt_request2.inputs())
            .await
            .unwrap();
        let saga2 = MeltSaga::new(
            std::sync::Arc::new(mint_for_new_op.clone()),
            mint_for_new_op.localstore(),
            mint_for_new_op.pubsub_manager(),
        );
        let setup_saga2 = saga2
            .setup_melt(
                &melt_request2,
                verification2,
                PaymentMethod::Known(KnownMethod::Bolt11),
            )
            .await
            .unwrap();
        *setup_saga2.state_data.operation.id()
    });

    // STEP 4: Wait for both tasks to complete
    let (recovery_result, new_op_result) = tokio::join!(recovery_task, new_operation_task);

    recovery_result.expect("Recovery task should complete");
    let new_operation_id = new_op_result.expect("New operation task should complete");

    // STEP 5: Verify recovery completed
    assert_saga_not_exists(&mint, &incomplete_operation_id).await;

    // STEP 6: Verify new operation succeeded
    assert_saga_exists(&mint, &new_operation_id).await;

    // SUCCESS: Concurrent recovery and operations work together!
}

// ============================================================================
// Failure Scenario Tests
// ============================================================================

/// Test: Double-spend detection during setup
#[tokio::test]
async fn test_double_spend_detection() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();

    // STEP 2: Setup first melt saga with proofs
    let quote1 = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let melt_request1 = create_test_melt_request(&proofs, &quote1);

    let verification1 = mint.verify_inputs(melt_request1.inputs()).await.unwrap();
    let saga1 = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let _setup_saga1 = saga1
        .setup_melt(
            &melt_request1,
            verification1,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    // Proofs should now be in PENDING state
    let input_ys = proofs.ys().unwrap();
    assert_proofs_state(&mint, &input_ys, Some(State::Pending)).await;

    // STEP 3: Try to setup second saga with same proofs
    let quote2 = create_test_melt_quote(&mint, Amount::from(8_000)).await;
    let melt_request2 = create_test_melt_request(&proofs, &quote2);

    // STEP 4: verify_inputs succeeds (only checks signatures)
    // but setup_melt should fail (checks proof states)
    let verification2 = mint.verify_inputs(melt_request2.inputs()).await.unwrap();
    let saga2 = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_result2 = saga2
        .setup_melt(
            &melt_request2,
            verification2,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await;

    // STEP 5: Verify second setup fails with appropriate error
    assert!(
        setup_result2.is_err(),
        "Second melt with same proofs should fail during setup"
    );

    if let Err(error) = setup_result2 {
        let error_msg = error.to_string().to_lowercase();
        assert!(
            error_msg.contains("pending")
                || error_msg.contains("spent")
                || error_msg.contains("state"),
            "Error should mention proof state issue, got: {}",
            error
        );
    }

    // STEP 6: Verify first saga is unaffected - proofs still pending
    assert_proofs_state(&mint, &input_ys, Some(State::Pending)).await;

    // SUCCESS: Double-spend prevented!
}

/// Test: Transaction balance validation
///
/// Note: This test verifies that the mint properly validates transaction balance.
/// In the current implementation, balance checking happens during melt request
/// validation before saga setup.
#[tokio::test]
async fn test_insufficient_funds() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();

    // STEP 2: Create proofs
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let input_ys = proofs.ys().unwrap();

    // STEP 3: Create quote
    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;

    // STEP 4: Setup a normal melt (this should succeed with sufficient funds)
    let melt_request = create_test_melt_request(&proofs, &quote);
    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_result = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await;

    // With 10000 msats input and 9000 msats quote, this should succeed
    assert!(
        setup_result.is_ok(),
        "Setup should succeed with sufficient funds"
    );

    // Clean up
    drop(setup_result);

    // Verify proofs are now marked pending (setup succeeded)
    assert_proofs_state(&mint, &input_ys, Some(State::Pending)).await;

    // SUCCESS: Balance validation works correctly!
    // Note: Testing actual insufficient funds would require creating a quote
    // that costs more than the proofs, but that's prevented at quote creation time
}

/// Test: Invalid quote ID rejection
#[tokio::test]
async fn test_invalid_quote_id() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();

    // STEP 2: Create a melt request with non-existent quote ID
    use cdk_common::nuts::MeltRequest;
    use cdk_common::QuoteId;

    let fake_quote_id = QuoteId::new_uuid();
    let melt_request = MeltRequest::new(fake_quote_id.clone(), proofs.clone(), None);

    // STEP 3: Try to setup melt saga (should fail due to invalid quote)
    let verification_result = mint.verify_inputs(melt_request.inputs()).await;

    // Verification might succeed (just checks signatures) or fail (if database issues)
    if let Ok(verification) = verification_result {
        let saga = MeltSaga::new(
            std::sync::Arc::new(mint.clone()),
            mint.localstore(),
            mint.pubsub_manager(),
        );
        let setup_result = saga
            .setup_melt(
                &melt_request,
                verification,
                PaymentMethod::Known(KnownMethod::Bolt11),
            )
            .await;

        // STEP 4: Verify setup fails with unknown quote error
        assert!(
            setup_result.is_err(),
            "Setup should fail with invalid quote ID"
        );

        if let Err(error) = setup_result {
            let error_msg = error.to_string().to_lowercase();
            assert!(
                error_msg.contains("quote")
                    || error_msg.contains("unknown")
                    || error_msg.contains("not found"),
                "Error should mention quote issue, got: {}",
                error
            );
        }

        // Note: We don't query database state after a failed setup because
        // the database may be in a transaction rollback state which can cause timeouts
    } else {
        // If verification fails due to database issues, that's also acceptable
        // for this test (we're mainly testing quote validation)
        eprintln!("Note: Verification failed (expected in some environments)");
    }

    // SUCCESS: Invalid quote ID handling works correctly!
}

/// Test: Quote already paid rejection
#[tokio::test]
async fn test_quote_already_paid() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();

    // STEP 2: Create and complete a full melt operation
    let proofs1 = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let melt_request1 = create_test_melt_request(&proofs1, &quote);

    // Complete the full melt flow
    let verification1 = mint.verify_inputs(melt_request1.inputs()).await.unwrap();
    let saga1 = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga1 = saga1
        .setup_melt(
            &melt_request1,
            verification1,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    let (payment_saga, decision) = setup_saga1
        .attempt_internal_settlement(&melt_request1)
        .await
        .unwrap();

    let confirmed_saga = payment_saga.make_payment(decision).await.unwrap();
    let _response = confirmed_saga.finalize().await.unwrap();

    // Verify quote is now paid
    let paid_quote = mint
        .localstore
        .get_melt_quote(&quote.id)
        .await
        .unwrap()
        .unwrap();
    assert_eq!(
        paid_quote.state,
        MeltQuoteState::Paid,
        "Quote should be paid"
    );

    // STEP 3: Try to setup new melt saga with the already-paid quote
    let proofs2 = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let melt_request2 = create_test_melt_request(&proofs2, &paid_quote);

    let verification2 = mint.verify_inputs(melt_request2.inputs()).await.unwrap();
    let saga2 = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_result2 = saga2
        .setup_melt(
            &melt_request2,
            verification2,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await;

    // STEP 4: Verify setup fails
    assert!(
        setup_result2.is_err(),
        "Setup should fail with already paid quote"
    );

    if let Err(error) = setup_result2 {
        let error_msg = error.to_string().to_lowercase();
        assert!(
            error_msg.contains("paid")
                || error_msg.contains("quote")
                || error_msg.contains("state"),
            "Error should mention paid quote, got: {}",
            error
        );
    }

    // SUCCESS: Already paid quote rejected!
}

/// Test: Quote already pending rejection
#[tokio::test]
async fn test_quote_already_pending() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();

    // STEP 2: Setup first melt saga (this puts quote in PENDING state)
    let proofs1 = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let melt_request1 = create_test_melt_request(&proofs1, &quote);

    let verification1 = mint.verify_inputs(melt_request1.inputs()).await.unwrap();
    let saga1 = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let _setup_saga1 = saga1
        .setup_melt(
            &melt_request1,
            verification1,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    // Verify quote is now pending
    let pending_quote = mint
        .localstore
        .get_melt_quote(&quote.id)
        .await
        .unwrap()
        .unwrap();
    assert_eq!(
        pending_quote.state,
        MeltQuoteState::Pending,
        "Quote should be pending"
    );

    // STEP 3: Try to setup second saga with same quote (different proofs)
    let proofs2 = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let melt_request2 = create_test_melt_request(&proofs2, &pending_quote);

    let verification2 = mint.verify_inputs(melt_request2.inputs()).await.unwrap();
    let saga2 = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_result2 = saga2
        .setup_melt(
            &melt_request2,
            verification2,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await;

    // STEP 4: Verify second setup fails
    assert!(
        setup_result2.is_err(),
        "Setup should fail with pending quote"
    );

    if let Err(error) = setup_result2 {
        let error_msg = error.to_string().to_lowercase();
        assert!(
            error_msg.contains("pending")
                || error_msg.contains("quote")
                || error_msg.contains("state"),
            "Error should mention pending quote, got: {}",
            error
        );
    }

    // SUCCESS: Concurrent quote use prevented!
}

// ============================================================================
// Edge Cases
// ============================================================================

/// Test: Empty input proofs
#[tokio::test]
async fn test_empty_inputs() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();

    // STEP 2: Create a melt request with empty proofs
    use cdk_common::nuts::{MeltRequest, Proofs};

    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let empty_proofs = Proofs::new();

    let melt_request = MeltRequest::new(quote.id.clone(), empty_proofs, None);

    // STEP 3: Try to verify inputs (should fail with empty proofs)
    let verification_result = mint.verify_inputs(melt_request.inputs()).await;

    // Verification should fail with empty inputs
    assert!(
        verification_result.is_err(),
        "Verification should fail with empty proofs"
    );

    let error = verification_result.unwrap_err();
    let error_msg = error.to_string().to_lowercase();
    assert!(
        error_msg.contains("empty") || error_msg.contains("no") || error_msg.contains("input"),
        "Error should mention empty inputs, got: {}",
        error
    );

    // STEP 4: Verify no saga persisted
    let sagas = mint
        .localstore
        .get_incomplete_sagas(OperationKind::Melt)
        .await
        .unwrap();
    assert!(sagas.is_empty(), "No saga should be persisted");

    // SUCCESS: Empty inputs rejected!
}

/// Test: Recovery with empty input_ys in saga
#[tokio::test]
async fn test_recovery_empty_input_ys() {
    // TODO: Implement this test
    // 1. Manually create saga with empty input_ys
    // 2. Run recovery
    // 3. Verify saga is skipped gracefully
    // 4. Verify logged warning
}

/// Test: Saga with no change outputs (simple melt scenario)
///
/// This test verifies that recovery works correctly when there are no
/// change outputs to clean up (e.g., when input amount exactly matches quote amount)
#[tokio::test]
async fn test_recovery_no_melt_request() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();

    // Create proofs that exactly match the quote amount (no change needed)
    let amount = Amount::from(10_000);
    let proofs = mint_test_proofs(&mint, amount).await.unwrap();
    let quote = create_test_melt_quote(&mint, amount).await;

    // Create melt request without change outputs
    let melt_request = create_test_melt_request(&proofs, &quote);
    assert!(
        melt_request.outputs().is_none(),
        "Should have no change outputs"
    );

    // STEP 2: Create incomplete saga
    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    let operation_id = *setup_saga.state_data.operation.id();
    let input_ys = proofs.ys().unwrap();

    // Drop saga (simulate crash)
    drop(setup_saga);

    // Verify saga exists
    assert_saga_exists(&mint, &operation_id).await;
    assert_proofs_state(&mint, &input_ys, Some(State::Pending)).await;

    // STEP 3: Run recovery
    // Should handle gracefully even with no change outputs to clean up
    mint.recover_from_incomplete_melt_sagas()
        .await
        .expect("Recovery should succeed without change outputs");

    // STEP 4: Verify recovery completed successfully
    assert_saga_not_exists(&mint, &operation_id).await;
    assert_proofs_state(&mint, &input_ys, None).await;

    // SUCCESS: Recovery works even without change outputs!
}

// ============================================================================
// Integration with check_pending_melt_quotes
// ============================================================================

/// Test: Saga recovery runs before quote checking on startup
///
/// This test verifies that saga recovery executes before quote checking,
/// preventing conflicts where both mechanisms might try to handle the same state.
#[tokio::test]
async fn test_recovery_order_on_startup() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();

    // STEP 2: Create incomplete saga with a pending quote
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let melt_request = create_test_melt_request(&proofs, &quote);

    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    let operation_id = *setup_saga.state_data.operation.id();
    let input_ys = proofs.ys().unwrap();

    // Drop saga (simulate crash) - this leaves quote in PENDING state
    drop(setup_saga);

    // Verify initial state: saga exists, quote is pending, proofs are pending
    assert_saga_exists(&mint, &operation_id).await;
    assert_proofs_state(&mint, &input_ys, Some(State::Pending)).await;

    let pending_quote = mint
        .localstore
        .get_melt_quote(&quote.id)
        .await
        .unwrap()
        .unwrap();
    assert_eq!(
        pending_quote.state,
        MeltQuoteState::Pending,
        "Quote should be pending"
    );

    // STEP 3: Manually trigger recovery (simulating startup)
    // Note: In production, mint.start() calls this automatically
    mint.recover_from_incomplete_melt_sagas()
        .await
        .expect("Recovery should succeed");

    // STEP 4: Verify saga recovery completed correctly
    // - Saga should be deleted
    // - Proofs should be removed (returned to client)
    // - Quote should be reset to UNPAID
    assert_saga_not_exists(&mint, &operation_id).await;
    assert_proofs_state(&mint, &input_ys, None).await;

    let recovered_quote = mint
        .localstore
        .get_melt_quote(&quote.id)
        .await
        .unwrap()
        .unwrap();
    assert_eq!(
        recovered_quote.state,
        MeltQuoteState::Unpaid,
        "Quote should be reset to unpaid"
    );

    // STEP 5: Verify no conflicts - system is in consistent state
    // Quote can be used again with new proofs
    let new_proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let new_request = create_test_melt_request(&new_proofs, &recovered_quote);

    let new_verification = mint.verify_inputs(new_request.inputs()).await.unwrap();
    let new_saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let _new_setup = new_saga
        .setup_melt(
            &new_request,
            new_verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    // SUCCESS: Recovery order is correct, no conflicts!
}

/// Test: Saga recovery and quote checking don't duplicate work
///
/// This test verifies that compensation is idempotent - running recovery
/// multiple times doesn't cause errors or duplicate work.
#[tokio::test]
async fn test_no_duplicate_recovery() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();

    // STEP 2: Create incomplete saga with pending quote
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let melt_request = create_test_melt_request(&proofs, &quote);

    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    let operation_id = *setup_saga.state_data.operation.id();
    let input_ys = proofs.ys().unwrap();

    // Drop saga (simulate crash)
    drop(setup_saga);

    // Verify saga exists and proofs are pending
    assert_saga_exists(&mint, &operation_id).await;
    assert_proofs_state(&mint, &input_ys, Some(State::Pending)).await;

    // STEP 3: Run recovery first time
    mint.recover_from_incomplete_melt_sagas()
        .await
        .expect("First recovery should succeed");

    // Verify saga deleted and proofs removed
    assert_saga_not_exists(&mint, &operation_id).await;
    assert_proofs_state(&mint, &input_ys, None).await;

    let recovered_quote = mint
        .localstore
        .get_melt_quote(&quote.id)
        .await
        .unwrap()
        .unwrap();
    assert_eq!(recovered_quote.state, MeltQuoteState::Unpaid);

    // STEP 4: Run recovery again (simulating duplicate execution)
    // Should be idempotent - no errors even though saga is already cleaned up
    mint.recover_from_incomplete_melt_sagas()
        .await
        .expect("Second recovery should succeed (idempotent)");

    // STEP 5: Verify state unchanged - still consistent
    assert_saga_not_exists(&mint, &operation_id).await;
    assert_proofs_state(&mint, &input_ys, None).await;

    let still_recovered_quote = mint
        .localstore
        .get_melt_quote(&quote.id)
        .await
        .unwrap()
        .unwrap();
    assert_eq!(still_recovered_quote.state, MeltQuoteState::Unpaid);

    // SUCCESS: Recovery is idempotent, no duplicate work or errors!
}

// ============================================================================
// Production Readiness Tests
// ============================================================================

/// Test: Operation ID uniqueness across multiple sagas
#[tokio::test]
async fn test_operation_id_uniqueness_and_tracking() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();

    // STEP 2: Create 10 sagas and collect their operation IDs
    // Using same amount for each to avoid FakeWallet limit issues
    let mut operation_ids = Vec::new();

    for _ in 0..10 {
        let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
        let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
        let melt_request = create_test_melt_request(&proofs, &quote);

        let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
        let saga = MeltSaga::new(
            std::sync::Arc::new(mint.clone()),
            mint.localstore(),
            mint.pubsub_manager(),
        );
        let setup_saga = saga
            .setup_melt(
                &melt_request,
                verification,
                PaymentMethod::Known(KnownMethod::Bolt11),
            )
            .await
            .unwrap();

        let operation_id = *setup_saga.state_data.operation.id();
        operation_ids.push(operation_id);

        // Keep saga alive
        drop(setup_saga);
    }

    // STEP 3: Verify all operation IDs are unique
    let unique_ids: std::collections::HashSet<_> = operation_ids.iter().collect();
    assert_eq!(
        unique_ids.len(),
        operation_ids.len(),
        "All {} operation IDs should be unique",
        operation_ids.len()
    );

    // STEP 4: Verify all sagas are trackable in database
    let sagas = mint
        .localstore
        .get_incomplete_sagas(OperationKind::Melt)
        .await
        .unwrap();

    for operation_id in &operation_ids {
        assert!(
            sagas.iter().any(|s| s.operation_id == *operation_id),
            "Saga {} should be trackable in database",
            operation_id
        );
    }

    // SUCCESS: All operation IDs are unique and trackable!
}

/// Test: Saga drop without finalize doesn't panic
#[tokio::test]
async fn test_saga_drop_without_finalize() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let melt_request = create_test_melt_request(&proofs, &quote);

    // STEP 2: Setup saga
    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();
    let operation_id = *setup_saga.state_data.operation.id();

    // STEP 3: Drop saga without finalizing (simulates crash)
    drop(setup_saga);

    // STEP 4: Verify no panic occurred and saga remains in database
    let saga_in_db = assert_saga_exists(&mint, &operation_id).await;
    assert_eq!(saga_in_db.operation_id, operation_id);

    // SUCCESS: Drop without finalize doesn't panic!
}

/// Test: Saga drop after payment is recoverable and finalizes correctly
///
/// This test verifies that when a saga is dropped after payment but before finalize,
/// the recovery process correctly finalizes the melt (marks proofs as spent) rather
/// than compensating (returning proofs to user). This is critical for preventing
/// fund loss where the mint pays the LN invoice but returns the proofs.
#[tokio::test]
async fn test_saga_drop_after_payment() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let input_ys = proofs.ys().unwrap();
    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let melt_request = create_test_melt_request(&proofs, &quote);

    // STEP 2: Setup saga and make payment
    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();
    let operation_id = *setup_saga.state_data.operation.id();

    // Verify proofs are PENDING after setup
    assert_proofs_state(&mint, &input_ys, Some(State::Pending)).await;

    // Attempt internal settlement
    let (payment_saga, decision) = setup_saga
        .attempt_internal_settlement(&melt_request)
        .await
        .unwrap();

    // Make payment
    let confirmed_saga = payment_saga.make_payment(decision).await.unwrap();

    // STEP 3: Verify saga state is now PaymentAttempted (not SetupComplete)
    let saga_in_db = assert_saga_exists(&mint, &operation_id).await;
    match &saga_in_db.state {
        cdk_common::mint::SagaStateEnum::Melt(state) => {
            assert_eq!(
                *state,
                MeltSagaState::PaymentAttempted,
                "Saga state should be PaymentAttempted after make_payment"
            );
        }
        _ => panic!("Expected Melt saga state"),
    }

    // STEP 4: Drop before finalize (simulates crash after payment)
    drop(confirmed_saga);

    // STEP 5: Run recovery to complete the operation
    mint.recover_from_incomplete_melt_sagas()
        .await
        .expect("Recovery should succeed");

    // STEP 6: Verify saga was recovered and cleaned up
    assert_saga_not_exists(&mint, &operation_id).await;

    // STEP 7: Verify proofs were marked SPENT (not returned to user)
    // This is the critical check - if compensation ran instead of finalize,
    // proofs would be None (returned) instead of Spent
    assert_proofs_state(&mint, &input_ys, Some(State::Spent)).await;

    // STEP 8: Verify quote is marked as PAID
    let final_quote = mint
        .localstore
        .get_melt_quote(&quote.id)
        .await
        .unwrap()
        .expect("Quote should exist");
    assert_eq!(
        final_quote.state,
        MeltQuoteState::Paid,
        "Quote should be marked as Paid after recovery finalization"
    );

    // SUCCESS: Drop after payment correctly finalizes (doesn't compensate)!
}

/// Test: PaymentAttempted state triggers LN backend check during recovery
///
/// This test verifies that when recovery finds a saga in PaymentAttempted state,
/// it checks the LN backend to determine whether to finalize or compensate,
/// rather than blindly compensating like SetupComplete state.
#[tokio::test]
async fn test_payment_attempted_state_triggers_ln_check() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let input_ys = proofs.ys().unwrap();
    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let melt_request = create_test_melt_request(&proofs, &quote);

    // STEP 2: Setup saga and make payment
    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();
    let operation_id = *setup_saga.state_data.operation.id();

    // Check initial state is SetupComplete
    let saga_before_payment = assert_saga_exists(&mint, &operation_id).await;
    match &saga_before_payment.state {
        cdk_common::mint::SagaStateEnum::Melt(state) => {
            assert_eq!(
                *state,
                MeltSagaState::SetupComplete,
                "Initial state should be SetupComplete"
            );
        }
        _ => panic!("Expected Melt saga state"),
    }

    // Attempt internal settlement and make payment
    let (payment_saga, decision) = setup_saga
        .attempt_internal_settlement(&melt_request)
        .await
        .unwrap();
    let confirmed_saga = payment_saga.make_payment(decision).await.unwrap();

    // STEP 3: Verify state transitioned to PaymentAttempted
    let saga_after_payment = assert_saga_exists(&mint, &operation_id).await;
    match &saga_after_payment.state {
        cdk_common::mint::SagaStateEnum::Melt(state) => {
            assert_eq!(
                *state,
                MeltSagaState::PaymentAttempted,
                "State should be PaymentAttempted after make_payment"
            );
        }
        _ => panic!("Expected Melt saga state"),
    }

    // STEP 4: Drop saga (simulate crash after payment but before finalize)
    drop(confirmed_saga);

    // STEP 5: Run recovery - should check LN backend and finalize
    mint.recover_from_incomplete_melt_sagas()
        .await
        .expect("Recovery should succeed");

    // STEP 6: Verify correct outcome - finalized, not compensated
    assert_saga_not_exists(&mint, &operation_id).await;

    // Proofs should be SPENT (finalized), not None (compensated)
    assert_proofs_state(&mint, &input_ys, Some(State::Spent)).await;

    // Quote should be PAID
    let final_quote = mint
        .localstore
        .get_melt_quote(&quote.id)
        .await
        .unwrap()
        .expect("Quote should exist");
    assert_eq!(
        final_quote.state,
        MeltQuoteState::Paid,
        "Quote should be Paid - LN backend check should have triggered finalization"
    );

    // SUCCESS: PaymentAttempted state correctly triggers LN check and finalizes!
}

/// Test: SetupComplete state compensates without LN check
///
/// This test verifies that when recovery finds a saga in SetupComplete state,
/// it compensates (returns proofs) without checking LN backend, because
/// payment was never sent.
#[tokio::test]
async fn test_setup_complete_state_compensates() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();
    let proofs = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let input_ys = proofs.ys().unwrap();
    let quote = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let melt_request = create_test_melt_request(&proofs, &quote);

    // STEP 2: Setup saga but don't make payment
    let verification = mint.verify_inputs(melt_request.inputs()).await.unwrap();
    let saga = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga = saga
        .setup_melt(
            &melt_request,
            verification,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();
    let operation_id = *setup_saga.state_data.operation.id();

    // Verify state is SetupComplete
    let saga_in_db = assert_saga_exists(&mint, &operation_id).await;
    match &saga_in_db.state {
        cdk_common::mint::SagaStateEnum::Melt(state) => {
            assert_eq!(
                *state,
                MeltSagaState::SetupComplete,
                "State should be SetupComplete"
            );
        }
        _ => panic!("Expected Melt saga state"),
    }

    // Verify proofs are PENDING
    assert_proofs_state(&mint, &input_ys, Some(State::Pending)).await;

    // STEP 3: Drop saga (simulate crash before payment)
    drop(setup_saga);

    // STEP 4: Run recovery - should compensate without LN check
    mint.recover_from_incomplete_melt_sagas()
        .await
        .expect("Recovery should succeed");

    // STEP 5: Verify correct outcome - compensated, not finalized
    assert_saga_not_exists(&mint, &operation_id).await;

    // Proofs should be None (compensated/returned), not Spent
    assert_proofs_state(&mint, &input_ys, None).await;

    // Quote should be UNPAID (reset)
    let final_quote = mint
        .localstore
        .get_melt_quote(&quote.id)
        .await
        .unwrap()
        .expect("Quote should exist");
    assert_eq!(
        final_quote.state,
        MeltQuoteState::Unpaid,
        "Quote should be Unpaid - compensation should have reset it"
    );

    // SUCCESS: SetupComplete state correctly compensates!
}

// ============================================================================
// Test Helpers
// ============================================================================

/// Helper: Create a test melt quote
///
/// # Arguments
/// * `mint` - Test mint instance
/// * `amount` - Amount in sats for the quote
///
/// # Returns
/// A valid unpaid melt quote
///
/// # How it works
/// Uses `create_fake_invoice()` from cdk-fake-wallet to generate a valid
/// bolt11 invoice that FakeWallet will process. The FakeInvoiceDescription
/// controls payment behavior (success/failure).
async fn create_test_melt_quote(
    mint: &crate::mint::Mint,
    amount: Amount,
) -> cdk_common::mint::MeltQuote {
    use cdk_common::melt::MeltQuoteRequest;
    use cdk_common::nuts::MeltQuoteBolt11Request;
    use cdk_common::CurrencyUnit;
    use cdk_fake_wallet::{create_fake_invoice, FakeInvoiceDescription};

    // Create fake invoice description (controls payment behavior)
    let fake_description = FakeInvoiceDescription {
        pay_invoice_state: MeltQuoteState::Paid, // Payment will succeed
        check_payment_state: MeltQuoteState::Paid, // Check will show paid
        pay_err: false,                          // No payment error
        check_err: false,                        // No check error
    };

    // Create valid bolt11 invoice (amount in millisats)
    // Amount is already in millisats, just convert to u64
    let amount_msats: u64 = amount.into();
    let invoice = create_fake_invoice(
        amount_msats,
        serde_json::to_string(&fake_description).unwrap(),
    );

    // Create melt quote request
    let bolt11_request = MeltQuoteBolt11Request {
        request: invoice,
        unit: CurrencyUnit::Sat,
        options: None,
    };

    let request = MeltQuoteRequest::Bolt11(bolt11_request);

    // Get quote from mint
    let quote_response = mint.get_melt_quote(request).await.unwrap();

    // Retrieve the full quote from database
    let quote = mint
        .localstore
        .get_melt_quote(&quote_response.quote)
        .await
        .unwrap()
        .expect("Quote should exist in database");

    quote
}

/// Helper: Create a test melt request
///
/// # Arguments
/// * `proofs` - Input proofs for the melt
/// * `quote` - Melt quote to use
///
/// # Returns
/// A MeltRequest ready to be used with setup_melt()
fn create_test_melt_request(
    proofs: &cdk_common::nuts::Proofs,
    quote: &cdk_common::mint::MeltQuote,
) -> cdk_common::nuts::MeltRequest<cdk_common::QuoteId> {
    use cdk_common::nuts::MeltRequest;

    MeltRequest::new(
        quote.id.clone(),
        proofs.clone(),
        None, // No change outputs for simplicity in tests
    )
}

/// Helper: Verify saga exists in database
async fn assert_saga_exists(mint: &crate::mint::Mint, operation_id: &uuid::Uuid) -> Saga {
    let sagas = mint
        .localstore
        .get_incomplete_sagas(OperationKind::Melt)
        .await
        .unwrap();

    sagas
        .into_iter()
        .find(|s| s.operation_id == *operation_id)
        .expect("Saga should exist in database")
}

/// Helper: Verify saga does not exist in database
async fn assert_saga_not_exists(mint: &crate::mint::Mint, operation_id: &uuid::Uuid) {
    let sagas = mint
        .localstore
        .get_incomplete_sagas(OperationKind::Melt)
        .await
        .unwrap();

    assert!(
        !sagas.iter().any(|s| s.operation_id == *operation_id),
        "Saga should not exist in database"
    );
}

/// Helper: Verify proofs are in expected state
async fn assert_proofs_state(
    mint: &crate::mint::Mint,
    ys: &[cdk_common::PublicKey],
    expected_state: Option<State>,
) {
    let states = mint.localstore.get_proofs_states(ys).await.unwrap();

    for state in states {
        assert_eq!(state, expected_state, "Proof state mismatch");
    }
}

// ============================================================================
// Duplicate request_lookup_id Constraint Tests
// ============================================================================

/// Test: Cannot set melt quote to pending if another quote with same lookup_id is already pending
///
/// This test verifies that when two melt quotes share the same request_lookup_id,
/// only one can be in PENDING state at a time.
#[tokio::test]
async fn test_duplicate_lookup_id_prevents_second_pending() {
    use cdk_common::melt::MeltQuoteRequest;
    use cdk_common::nuts::MeltQuoteBolt11Request;
    use cdk_common::CurrencyUnit;
    use cdk_fake_wallet::{create_fake_invoice, FakeInvoiceDescription};

    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();

    // Create a fake invoice description
    let fake_description = FakeInvoiceDescription {
        pay_invoice_state: MeltQuoteState::Paid,
        check_payment_state: MeltQuoteState::Paid,
        pay_err: false,
        check_err: false,
    };

    // Create a single invoice that will be used for both quotes
    let amount_msats: u64 = 9000;
    let invoice = create_fake_invoice(
        amount_msats,
        serde_json::to_string(&fake_description).unwrap(),
    );

    // STEP 2: Create two melt quotes for the same invoice (same request_lookup_id)
    let bolt11_request1 = MeltQuoteBolt11Request {
        request: invoice.clone(),
        unit: CurrencyUnit::Sat,
        options: None,
    };
    let quote_response1 = mint
        .get_melt_quote(MeltQuoteRequest::Bolt11(bolt11_request1))
        .await
        .unwrap();

    let bolt11_request2 = MeltQuoteBolt11Request {
        request: invoice,
        unit: CurrencyUnit::Sat,
        options: None,
    };
    let quote_response2 = mint
        .get_melt_quote(MeltQuoteRequest::Bolt11(bolt11_request2))
        .await
        .unwrap();

    // Retrieve full quotes
    let quote1 = mint
        .localstore
        .get_melt_quote(&quote_response1.quote)
        .await
        .unwrap()
        .expect("Quote 1 should exist");

    let quote2 = mint
        .localstore
        .get_melt_quote(&quote_response2.quote)
        .await
        .unwrap()
        .expect("Quote 2 should exist");

    // Verify both quotes have the same lookup_id
    assert_eq!(
        quote1.request_lookup_id, quote2.request_lookup_id,
        "Both quotes should have the same request_lookup_id"
    );

    // STEP 3: Setup first melt saga (puts quote1 in PENDING state)
    let proofs1 = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let melt_request1 = create_test_melt_request(&proofs1, &quote1);

    let verification1 = mint.verify_inputs(melt_request1.inputs()).await.unwrap();
    let saga1 = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga1 = saga1
        .setup_melt(
            &melt_request1,
            verification1,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    // Continue through the payment flow to release any transaction locks
    // The quote will stay in PENDING state because FakeWallet returns Paid
    // but we don't call finalize()
    let (payment_saga1, decision1) = setup_saga1
        .attempt_internal_settlement(&melt_request1)
        .await
        .unwrap();

    // Make payment but don't finalize - keeps quote in PENDING
    let confirmed_saga1 = payment_saga1.make_payment(decision1).await.unwrap();

    // Drop the saga to release resources (simulates crash before finalize)
    drop(confirmed_saga1);

    // Verify quote1 is now pending
    let pending_quote1 = mint
        .localstore
        .get_melt_quote(&quote1.id)
        .await
        .unwrap()
        .unwrap();
    assert_eq!(
        pending_quote1.state,
        MeltQuoteState::Pending,
        "Quote 1 should be pending"
    );

    // STEP 4: Try to setup second saga with quote2 (same lookup_id)
    let proofs2 = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let melt_request2 = create_test_melt_request(&proofs2, &quote2);

    let verification2 = mint.verify_inputs(melt_request2.inputs()).await.unwrap();
    let saga2 = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_result2 = saga2
        .setup_melt(
            &melt_request2,
            verification2,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await;

    // STEP 5: Verify second setup fails due to duplicate pending lookup_id
    assert!(
        setup_result2.is_err(),
        "Setup should fail when another quote with same lookup_id is already pending"
    );

    if let Err(error) = setup_result2 {
        let error_msg = error.to_string().to_lowercase();
        assert!(
            error_msg.contains("duplicate")
                || error_msg.contains("pending")
                || error_msg.contains("already paid"),
            "Error should mention duplicate, pending, or already paid, got: {}",
            error
        );
    }

    // Verify quote2 is still unpaid
    let still_unpaid_quote2 = mint
        .localstore
        .get_melt_quote(&quote2.id)
        .await
        .unwrap()
        .unwrap();

    assert_eq!(
        still_unpaid_quote2.state,
        MeltQuoteState::Unpaid,
        "Quote 2 should still be unpaid"
    );

    // SUCCESS: Duplicate pending lookup_id prevented!
}

/// Test: Cannot set melt quote to pending if another quote with same lookup_id is already paid
///
/// This test verifies that once a melt quote with a specific request_lookup_id is paid,
/// no other quote with the same lookup_id can transition to pending.
#[tokio::test]
async fn test_paid_lookup_id_prevents_pending() {
    use cdk_common::melt::MeltQuoteRequest;
    use cdk_common::nuts::MeltQuoteBolt11Request;
    use cdk_common::CurrencyUnit;
    use cdk_fake_wallet::{create_fake_invoice, FakeInvoiceDescription};

    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();

    // Create a fake invoice description
    let fake_description = FakeInvoiceDescription {
        pay_invoice_state: MeltQuoteState::Paid,
        check_payment_state: MeltQuoteState::Paid,
        pay_err: false,
        check_err: false,
    };

    // Create a single invoice that will be used for both quotes
    let amount_msats: u64 = 9000;
    let invoice = create_fake_invoice(
        amount_msats,
        serde_json::to_string(&fake_description).unwrap(),
    );

    // STEP 2: Create two melt quotes for the same invoice (same request_lookup_id)
    let bolt11_request1 = MeltQuoteBolt11Request {
        request: invoice.clone(),
        unit: CurrencyUnit::Sat,
        options: None,
    };
    let quote_response1 = mint
        .get_melt_quote(MeltQuoteRequest::Bolt11(bolt11_request1))
        .await
        .unwrap();

    let bolt11_request2 = MeltQuoteBolt11Request {
        request: invoice,
        unit: CurrencyUnit::Sat,
        options: None,
    };
    let quote_response2 = mint
        .get_melt_quote(MeltQuoteRequest::Bolt11(bolt11_request2))
        .await
        .unwrap();

    // Retrieve full quotes
    let quote1 = mint
        .localstore
        .get_melt_quote(&quote_response1.quote)
        .await
        .unwrap()
        .expect("Quote 1 should exist");
    let quote2 = mint
        .localstore
        .get_melt_quote(&quote_response2.quote)
        .await
        .unwrap()
        .expect("Quote 2 should exist");

    // STEP 3: Complete the first melt (marks quote1 as PAID)
    let proofs1 = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let melt_request1 = create_test_melt_request(&proofs1, &quote1);

    let verification1 = mint.verify_inputs(melt_request1.inputs()).await.unwrap();
    let saga1 = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_saga1 = saga1
        .setup_melt(
            &melt_request1,
            verification1,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    // Complete the full melt flow for quote1
    let (payment_saga, decision) = setup_saga1
        .attempt_internal_settlement(&melt_request1)
        .await
        .unwrap();
    let confirmed_saga = payment_saga.make_payment(decision).await.unwrap();
    let _response = confirmed_saga.finalize().await.unwrap();

    // Verify quote1 is now paid
    let paid_quote1 = mint
        .localstore
        .get_melt_quote(&quote1.id)
        .await
        .unwrap()
        .unwrap();
    assert_eq!(
        paid_quote1.state,
        MeltQuoteState::Paid,
        "Quote 1 should be paid"
    );

    // STEP 4: Try to setup second saga with quote2 (same lookup_id as paid quote)
    let proofs2 = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let melt_request2 = create_test_melt_request(&proofs2, &quote2);

    let verification2 = mint.verify_inputs(melt_request2.inputs()).await.unwrap();
    let saga2 = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let setup_result2 = saga2
        .setup_melt(
            &melt_request2,
            verification2,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await;

    // STEP 5: Verify second setup fails due to already paid lookup_id
    assert!(
        setup_result2.is_err(),
        "Setup should fail when another quote with same lookup_id is already paid"
    );

    if let Err(error) = setup_result2 {
        let error_msg = error.to_string().to_lowercase();
        assert!(
            error_msg.contains("duplicate")
                || error_msg.contains("paid")
                || error_msg.contains("pending"),
            "Error should mention duplicate or paid, got: {}",
            error
        );
    }

    // SUCCESS: Paid lookup_id prevents new pending!
}

/// Test: Different lookup_ids allow concurrent pending quotes
///
/// This test verifies that melt quotes with different request_lookup_ids
/// can both be in PENDING state simultaneously.
#[tokio::test]
async fn test_different_lookup_ids_allow_concurrent_pending() {
    // STEP 1: Setup test environment
    let mint = create_test_mint().await.unwrap();

    // STEP 2: Create two quotes with different lookup_ids (different invoices)
    let quote1 = create_test_melt_quote(&mint, Amount::from(9_000)).await;
    let quote2 = create_test_melt_quote(&mint, Amount::from(8_000)).await;

    // Verify quotes have different lookup_ids
    assert_ne!(
        quote1.request_lookup_id, quote2.request_lookup_id,
        "Quotes should have different request_lookup_ids"
    );

    // STEP 3: Setup first saga (puts quote1 in PENDING state)
    let proofs1 = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let melt_request1 = create_test_melt_request(&proofs1, &quote1);

    let verification1 = mint.verify_inputs(melt_request1.inputs()).await.unwrap();
    let saga1 = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let _setup_saga1 = saga1
        .setup_melt(
            &melt_request1,
            verification1,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    // STEP 4: Setup second saga (puts quote2 in PENDING state)
    let proofs2 = mint_test_proofs(&mint, Amount::from(10_000)).await.unwrap();
    let melt_request2 = create_test_melt_request(&proofs2, &quote2);

    let verification2 = mint.verify_inputs(melt_request2.inputs()).await.unwrap();
    let saga2 = MeltSaga::new(
        std::sync::Arc::new(mint.clone()),
        mint.localstore(),
        mint.pubsub_manager(),
    );
    let _setup_saga2 = saga2
        .setup_melt(
            &melt_request2,
            verification2,
            PaymentMethod::Known(KnownMethod::Bolt11),
        )
        .await
        .unwrap();

    // STEP 5: Verify both quotes are pending
    let pending_quote1 = mint
        .localstore
        .get_melt_quote(&quote1.id)
        .await
        .unwrap()
        .unwrap();
    let pending_quote2 = mint
        .localstore
        .get_melt_quote(&quote2.id)
        .await
        .unwrap()
        .unwrap();

    assert_eq!(
        pending_quote1.state,
        MeltQuoteState::Pending,
        "Quote 1 should be pending"
    );
    assert_eq!(
        pending_quote2.state,
        MeltQuoteState::Pending,
        "Quote 2 should be pending"
    );

    // SUCCESS: Different lookup_ids allow concurrent pending!
}