trader-bot 0.2.0

//! Binance exchange adapter.
//!
//! This module provides an adapter for the Binance cryptocurrency exchange API.
//!
//! # Implementation Status
//!
//! This is a placeholder implementation. To complete it:
//! 1. Add the Binance SDK to dependencies
//! 2. Implement authentication with API key/secret
//! 3. Implement market data streaming (WebSocket)
//! 4. Implement order execution

use crate::domain::{Money, Order, OrderDirection, Wallet};
use crate::exchange::{
    ExchangeError, ExchangeInfo, ExchangeProvider, ExchangeResult, Instrument, InstrumentType,
    MarketData, MarketStatus, OrderBook,
};
use async_trait::async_trait;
use std::collections::HashMap;
use std::sync::RwLock;

/// Binance exchange adapter.
///
/// This adapter connects to the Binance API for cryptocurrency trading.
#[derive(Debug)]
pub struct BinanceAdapter {
    info: ExchangeInfo,
    api_key: Option<String>,
    api_secret: Option<String>,
    testnet: bool,
    connected: RwLock<bool>,
    // Placeholder for real API client
    accounts: RwLock<HashMap<String, AccountState>>,
}

#[derive(Debug, Clone)]
struct AccountState {
    wallet: Wallet,
}

impl BinanceAdapter {
    /// Creates a new Binance adapter.
    #[must_use]
    pub fn new() -> Self {
        Self {
            info: ExchangeInfo {
                id: "binance".into(),
                name: "Binance".into(),
                url: "https://www.binance.com/".into(),
                supported_types: vec![InstrumentType::Crypto],
            },
            api_key: None,
            api_secret: None,
            testnet: true,
            connected: RwLock::new(false),
            accounts: RwLock::new(HashMap::new()),
        }
    }

    /// Creates a new Binance adapter with API credentials.
    #[must_use]
    pub fn with_credentials(api_key: impl Into<String>, api_secret: impl Into<String>) -> Self {
        let mut adapter = Self::new();
        adapter.api_key = Some(api_key.into());
        adapter.api_secret = Some(api_secret.into());
        adapter
    }

    /// Sets whether to use testnet.
    #[must_use]
    pub fn with_testnet(mut self, testnet: bool) -> Self {
        self.testnet = testnet;
        self
    }

    /// Connects to the Binance API.
    ///
    /// # Errors
    ///
    /// Returns an error if API credentials are not configured.
    pub fn connect(&self) -> ExchangeResult<()> {
        if self.api_key.is_none() || self.api_secret.is_none() {
            return Err(ExchangeError::ConfigurationError(
                "API key and secret are required".into(),
            ));
        }

        // TODO: Implement actual connection to Binance API
        *self.connected.write().unwrap() = true;
        Ok(())
    }

    fn ensure_connected(&self) -> ExchangeResult<()> {
        if !*self.connected.read().unwrap() {
            return Err(ExchangeError::NetworkError("Not connected".into()));
        }
        Ok(())
    }
}

impl Default for BinanceAdapter {
    fn default() -> Self {
        Self::new()
    }
}

#[async_trait]
impl ExchangeProvider for BinanceAdapter {
    fn info(&self) -> &ExchangeInfo {
        &self.info
    }

    async fn ping(&self) -> ExchangeResult<()> {
        self.ensure_connected()?;
        // TODO: Implement actual ping
        Ok(())
    }

    async fn get_wallet(&self, account_id: &str) -> ExchangeResult<Wallet> {
        self.ensure_connected()?;
        let accounts = self.accounts.read().unwrap();
        accounts
            .get(account_id)
            .map(|s| s.wallet.clone())
            .ok_or_else(|| ExchangeError::Internal(format!("Account {} not found", account_id)))
    }

    async fn get_instrument(&self, symbol: &str) -> ExchangeResult<Instrument> {
        self.ensure_connected()?;
        // TODO: Implement actual instrument lookup
        Err(ExchangeError::InstrumentNotFound(symbol.into()))
    }

    async fn list_instruments(&self) -> ExchangeResult<Vec<Instrument>> {
        self.ensure_connected()?;
        // TODO: Implement actual instrument listing
        Ok(Vec::new())
    }

    async fn get_market_data(&self, symbol: &str) -> ExchangeResult<MarketData> {
        self.ensure_connected()?;
        // TODO: Implement actual market data fetch
        Ok(MarketData {
            symbol: symbol.into(),
            last_price: Money::zero("USDT"),
            bid: None,
            ask: None,
            volume_24h: None,
            high_24h: None,
            low_24h: None,
            change_24h: None,
            change_percent_24h: None,
            market_status: MarketStatus::Open, // Crypto markets are 24/7
            timestamp: chrono::Utc::now(),
        })
    }

    async fn get_market_data_batch(&self, symbols: &[String]) -> ExchangeResult<Vec<MarketData>> {
        self.ensure_connected()?;
        let mut results = Vec::new();
        for symbol in symbols {
            results.push(self.get_market_data(symbol).await?);
        }
        Ok(results)
    }

    async fn get_order_book(&self, symbol: &str, _depth: u32) -> ExchangeResult<OrderBook> {
        self.ensure_connected()?;
        // TODO: Implement actual order book fetch
        Ok(OrderBook::empty(symbol))
    }

    async fn place_order(&self, _account_id: &str, order: Order) -> ExchangeResult<Order> {
        self.ensure_connected()?;
        // TODO: Implement actual order placement
        Err(ExchangeError::OrderRejected(format!(
            "Order placement not implemented for {}",
            order.symbol()
        )))
    }

    async fn cancel_order(&self, _account_id: &str, order_id: &str) -> ExchangeResult<Order> {
        self.ensure_connected()?;
        // TODO: Implement actual order cancellation
        Err(ExchangeError::OrderNotFound(order_id.into()))
    }

    async fn get_order(&self, _account_id: &str, order_id: &str) -> ExchangeResult<Order> {
        self.ensure_connected()?;
        // TODO: Implement actual order lookup
        Err(ExchangeError::OrderNotFound(order_id.into()))
    }

    async fn get_active_orders(&self, _account_id: &str) -> ExchangeResult<Vec<Order>> {
        self.ensure_connected()?;
        // TODO: Implement actual active orders fetch
        Ok(Vec::new())
    }

    async fn is_market_open(&self, _symbol: &str) -> ExchangeResult<bool> {
        self.ensure_connected()?;
        // Crypto markets are always open
        Ok(true)
    }

    async fn market_buy(&self, account_id: &str, symbol: &str, lots: u32) -> ExchangeResult<Order> {
        let order = Order::market(
            uuid::Uuid::new_v4().to_string(),
            symbol,
            &self.info.id,
            OrderDirection::Buy,
            lots,
        );
        self.place_order(account_id, order).await
    }

    async fn market_sell(
        &self,
        account_id: &str,
        symbol: &str,
        lots: u32,
    ) -> ExchangeResult<Order> {
        let order = Order::market(
            uuid::Uuid::new_v4().to_string(),
            symbol,
            &self.info.id,
            OrderDirection::Sell,
            lots,
        );
        self.place_order(account_id, order).await
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_adapter_creation() {
        let adapter = BinanceAdapter::new();
        assert_eq!(adapter.info().id, "binance");
        assert!(adapter.testnet);
    }

    #[test]
    fn test_adapter_with_credentials() {
        let adapter = BinanceAdapter::with_credentials("key", "secret");
        assert!(adapter.api_key.is_some());
        assert!(adapter.api_secret.is_some());
    }

    #[test]
    fn test_connect_without_credentials() {
        let adapter = BinanceAdapter::new();
        let result = adapter.connect();
        assert!(result.is_err());
    }
}