"""组合策略 API 路由(异步化 P0)。

POST /portfolio/backtest: 异步提交组合回测任务,返回 task_id 供前端轮询。
GET  /portfolio/task/{task_id}/result: 取组合回测结果。

回测子进程执行(三机自适应 NAS/VPS/Mac-SSH)搬至 portfolio_worker.py,
超时从 600s 提升至 3600s。复用 sanguo_orchestrator task 框架。
"""
from __future__ import annotations

import logging
from typing import Any

from fastapi import APIRouter, Depends, Header, HTTPException
from pydantic import BaseModel, Field

from .auth import verify_token as verify_token_impl
from .routes import get_orchestrator

logger = logging.getLogger(__name__)
router = APIRouter()


async def verify_token(authorization: str | None = Header(None)):
    if authorization is None or not authorization.startswith("Bearer "):
        raise HTTPException(401, "Missing/invalid authorization")
    return verify_token_impl(authorization.split(" ", 1)[1])


class PortfolioBacktestRequest(BaseModel):
    pool: str = Field(default="hs300_subset", description="标的池(占位,MVP 用默认)")
    start_date: str = Field(default="2024-01-01", description="YYYY-MM-DD")
    end_date: str = Field(default="2024-02-29", description="YYYY-MM-DD")
    initial_cash: float = Field(default=1_000_000.0, description="初始资金(元)")
    benchmark: str = Field(default="000300.XSHG", description="基准代码")
    strategy: str = Field(
        default="all_weather",
        description="策略: all_weather/momentum_timing/value_selection/small_cap",
    )
    max_pool: int = Field(default=30, description="选股池上限: 0=全市场不限, N=前N只(MVP验证用)")
    # A 股费用(对齐个股回测)
    commission_rate: float = Field(default=0.0003, description="佣金率双边(万3=0.0003)")
    stamp_duty_rate: float = Field(default=0.001, description="印花税率卖出(千1=0.001)")
    min_commission: float = Field(default=5.0, description="单笔最低佣金(元)")
    slippage: float = Field(default=0.0, description="滑点比率(万10=0.001,0=不加)")


@router.post("/portfolio/backtest", dependencies=[Depends(verify_token)])
async def run_portfolio_backtest(req: PortfolioBacktestRequest):
    """异步提交组合回测任务,返回 task_id。前端轮询 GET /task/{id} 再取结果。"""
    tid = await get_orchestrator().submit_portfolio(
        start=req.start_date,
        end=req.end_date,
        cash=req.initial_cash,
        benchmark=req.benchmark,
        strategy=req.strategy,
        max_pool=req.max_pool,
        provider_config=None,
        commission_rate=req.commission_rate,
        stamp_duty_rate=req.stamp_duty_rate,
        min_commission=req.min_commission,
        slippage=req.slippage,
    )
    return {"task_id": tid}


@router.get("/portfolio/task/{task_id}/result", dependencies=[Depends(verify_token)])
def get_portfolio_result(task_id: str):
    """取组合回测结果。从 BacktestResult.statistics 取 metrics/stocks_selected/period,
    从 equity_curve/trades(DataFrame)转 records。"""
    # 区分 failed(422+error)/running·pending(404 not ready)/done(result)/not found(404)。
    # 原实现对跑中/失败都 404,排查困难(分不清慢/死/失败)。
    orch = get_orchestrator()
    state = orch.get_status(task_id)
    if state is None:
        r = orch.get_result(task_id)  # 不在内存池(历史 task 持久化 DB)→直接查 DB
        if r is None:
            raise HTTPException(status_code=404, detail="task not found")
    elif state.value == "failed":
        task = orch.pool.get_task(task_id)
        raise HTTPException(
            status_code=422,
            detail=f"task failed: {task.error_msg if task else 'unknown'}",
        )
    elif state.value != "done":
        raise HTTPException(
            status_code=404, detail=f"result not ready (state={state.value})"
        )
    else:
        r = orch.get_result(task_id)
        if r is None:
            raise HTTPException(status_code=404, detail="done but result missing")

    stats: dict = r.statistics or {}
    metrics = stats.get("metrics", {})
    stocks_selected = stats.get("stocks_selected", [])
    period = stats.get("period", {})

    return {
        "task_id": task_id,
        "strategy": r.strategy,
        "period": period,
        "metrics": metrics,
        "equity_curve": _df_to_records(r.equity_curve),
        "trades": _df_to_records(r.trades),
        "stocks_selected": stocks_selected,
    }


@router.get("/portfolio/task/{task_id}/status", dependencies=[Depends(verify_token)])
def get_portfolio_status(task_id: str):
    """组合回测任务状态(区分 pending/running/done/failed + error 详情)。
    通用 GET /task/{id} 也返 status,本接口聚焦 portfolio 命名空间 + error 字段。"""
    orch = get_orchestrator()
    state = orch.get_status(task_id)
    if state is None:
        raise HTTPException(status_code=404, detail="task not found")
    task = orch.pool.get_task(task_id)
    return {
        "task_id": task_id,
        "state": state.value if hasattr(state, "value") else str(state),
        "stage": orch.pool.get_stage(task_id) or "",
        "error": task.error_msg if (task and isinstance(task.error_msg, str)) else None,
    }


def _df_to_records(df: Any) -> list[dict]:
    """DataFrame/list → list[dict] (empty-safe)."""
    if df is None:
        return []
    if hasattr(df, "empty") and df.empty:
        return []
    if hasattr(df, "to_dict"):
        return df.to_dict(orient="records")
    if isinstance(df, list):
        return df
    return []