from typing import List, Optional
from fastapi import APIRouter, BackgroundTasks, HTTPException
from datetime import datetime
from app.models.schemas import (
    BacktestConfig,
    BacktestMetrics,
    BacktestStatusEnum,
    Trade,
)
from app.utils.logger import get_logger
import uuid

logger = get_logger(__name__)

router = APIRouter()

_backtest_store: dict = {}
_backtest_results: dict = {}


@router.post("/start")
async def start_backtest(config: BacktestConfig, name: Optional[str] = None):
    backtest_id = str(uuid.uuid4())
    
    _backtest_store[backtest_id] = {
        "backtest_id": backtest_id,
        "name": name or f"Backtest {backtest_id[:8]}",
        "status": BacktestStatusEnum.RUNNING,
        "config": config.dict(),
        "created_at": datetime.utcnow(),
        "started_at": datetime.utcnow(),
        "completed_at": None,
        "error_message": None,
    }

    logger.info(f"Backtest started: {backtest_id}")

    return {
        "backtest_id": backtest_id,
        "status": BacktestStatusEnum.RUNNING,
        "name": _backtest_store[backtest_id]["name"],
    }


@router.get("/{backtest_id}")
async def get_backtest_status(backtest_id: str):
    if backtest_id not in _backtest_store:
        raise HTTPException(status_code=404, detail=f"Backtest {backtest_id} not found")

    backtest = _backtest_store[backtest_id]
    result = _backtest_results.get(backtest_id)

    return {
        "status": backtest["status"],
        "name": backtest["name"],
        "created_at": backtest["created_at"],
        "started_at": backtest["started_at"],
        "completed_at": backtest["completed_at"],
        "error_message": backtest["error_message"],
        "results": result if backtest["status"] == BacktestStatusEnum.COMPLETED else None,
    }


@router.get("/{backtest_id}/results")
async def get_backtest_results(backtest_id: str):
    if backtest_id not in _backtest_results:
        raise HTTPException(status_code=404, detail=f"Results for backtest {backtest_id} not found")

    return _backtest_results[backtest_id]


@router.get("/{backtest_id}/trades")
async def get_backtest_trades(backtest_id: str, limit: int = 100):
    if backtest_id not in _backtest_store:
        raise HTTPException(status_code=404, detail=f"Backtest {backtest_id} not found")

    trades = _backtest_results.get(backtest_id, {}).get("trades", [])
    return {"backtest_id": backtest_id, "trades": trades[-limit:], "total": len(trades)}


@router.get("/history")
async def get_backtest_history():
    backtests = []
    for backtest_id, backtest in _backtest_store.items():
        backtests.append(
            {
                "backtest_id": backtest_id,
                "name": backtest["name"],
                "status": backtest["status"],
                "created_at": backtest["created_at"],
                "completed_at": backtest["completed_at"],
            }
        )

    return {"backtests": backtests, "total": len(backtests)}


@router.delete("/{backtest_id}")
async def delete_backtest(backtest_id: str):
    if backtest_id not in _backtest_store:
        raise HTTPException(status_code=404, detail=f"Backtest {backtest_id} not found")

    del _backtest_store[backtest_id]
    if backtest_id in _backtest_results:
        del _backtest_results[backtest_id]

    logger.info(f"Backtest deleted: {backtest_id}")
    return {"message": f"Backtest {backtest_id} deleted"}