"""
执行层抽象接口（通用）

只提供抽象基类和Portfolio数据结构，具体执行器可扩展
"""

from abc import ABC, abstractmethod
from typing import Dict, List, Optional
import pandas as pd
from datetime import datetime

from framework.risk import Position


class Portfolio:
    """
    投资组合数据结构（通用）
    
    用于管理持仓集合
    """
    
    def __init__(self, initial_capital: float = 100000):
        """初始化投资组合"""
        self.initial_capital = initial_capital
        self.cash = initial_capital
        self.positions: Dict[str, Position] = {}
        self.trades: List[Dict] = []
        self._net_value_history: List[float] = []
    
    def add_position(self, code: str, price: float, quantity: float, time: datetime) -> None:
        """添加持仓"""
        position = Position(
            code=code,
            entry_price=price,
            current_price=price,
            entry_time=time,
            quantity=quantity
        )
        self.positions[code] = position
        self.cash -= price * quantity
        
        self.trades.append({
            'action': 'BUY',
            'code': code,
            'price': price,
            'quantity': quantity,
            'time': time
        })
    
    def remove_position(self, code: str, price: float, time: datetime) -> float:
        """移除持仓"""
        if code not in self.positions:
            return 0
        
        position = self.positions[code]
        profit = (price - position.entry_price) * position.quantity
        self.cash += price * position.quantity
        
        del self.positions[code]
        
        self.trades.append({
            'action': 'SELL',
            'code': code,
            'price': price,
            'quantity': position.quantity,
            'time': time,
            'profit': profit
        })
        
        return profit
    
    def update_prices(self, prices: Dict[str, float]) -> None:
        """更新持仓价格"""
        for code, price in prices.items():
            if code in self.positions:
                self.positions[code].current_price = price
    
    def get_net_value(self) -> float:
        """计算净值"""
        positions_value = sum(
            pos.current_price * pos.quantity for pos in self.positions.values()
        )
        return self.cash + positions_value
    
    def record_net_value(self) -> None:
        """记录当前净值"""
        self._net_value_history.append(self.get_net_value())
    
    def get_net_value_series(self) -> pd.Series:
        """获取净值序列"""
        return pd.Series(self._net_value_history)
    
    def get_weight(self, code: str) -> float:
        """计算持仓权重"""
        if code not in self.positions:
            return 0
        
        position_value = self.positions[code].current_price * self.positions[code].quantity
        return position_value / self.get_net_value()
    
    def __repr__(self) -> str:
        return f"Portfolio(capital={self.cash:.2f}, positions={len(self.positions)})"


class Executor(ABC):
    """
    执行器抽象基类
    
    所有执行器必须实现execute方法
    """
    
    mode: str = "base"
    
    def __init__(self, **params):
        """初始化执行器参数"""
        self._params = params
    
    @abstractmethod
    def execute(self, signals: pd.DataFrame, data: pd.DataFrame) -> Portfolio:
        """
        执行信号
        
        Args:
            signals: 信号DataFrame
            data: OHLCV数据
            
        Returns:
            Portfolio对象
        """
        pass
    
    def __repr__(self) -> str:
        params_str = ', '.join([f"{k}={v}" for k, v in self._params.items()])
        return f"{self.__class__.__name__}({params_str})"


class BacktestExecutor(Executor):
    """
    回测执行器（通用骨架）
    
    具体回测逻辑需要在strategies中定制实现
    """
    
    mode = "backtest"
    
    def __init__(self, initial_capital: float = 100000, trade_cost: float = 0.001):
        super().__init__(initial_capital=initial_capital, trade_cost=trade_cost)
        self.initial_capital = initial_capital
        self.trade_cost = trade_cost
    
    def execute(self, signals: pd.DataFrame, data: pd.DataFrame) -> Portfolio:
        """
        执行回测（简化版本）
        
        完整回测逻辑需要定制实现
        """
        portfolio = Portfolio(self.initial_capital)
        
        # 这里只提供骨架，具体逻辑需要定制实现
        # 包括：净值计算、交易成本扣除、基准对比等
        
        return portfolio


class DryRunExecutor(Executor):
    """
    Dry-run执行器（通用）
    
    用于模拟运行，不实际执行交易
    """
    
    mode = "dry_run"
    
    def __init__(self, verbose: bool = True):
        super().__init__(verbose=verbose)
        self.verbose = verbose
    
    def execute(self, signals: pd.DataFrame, data: pd.DataFrame) -> Portfolio:
        """模拟执行"""
        portfolio = Portfolio(100000)
        
        for date in signals.index:
            signal = signals.loc[date, 'signal']
            
            if signal and self.verbose:
                print(f"[{date}] Signal: {signal}")
        
        return portfolio


# 导出抽象接口
__all__ = ['Portfolio', 'Executor', 'BacktestExecutor', 'DryRunExecutor']