"""回测路由。"""
from __future__ import annotations

import logging

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

from src.api.deps import require_admin
from src.llm.backtest import run_backtest

logger = logging.getLogger(__name__)

router = APIRouter(prefix="/api/v1", tags=["backtest"])


class BacktestRequest(BaseModel):
    league_id: int | None = Field(None, description="联赛 ID")
    date_from: str | None = Field(None, description="起始日期 YYYY-MM-DD")
    date_to: str | None = Field(None, description="结束日期 YYYY-MM-DD")
    mode: str = Field("single", description="预测模式: single(快) / multi(多 agent)")
    limit: int = Field(20, ge=1, le=200, description="最大回测场数")
    model: str | None = Field(None, description="指定模型 (空=默认)")


@router.post("/backtest", dependencies=[Depends(require_admin)])
async def backtest(req: BacktestRequest):
    """对历史比赛运行回测。

    该接口会对每场已完赛比赛各发起一次 LLM 预测,成本高 —— 因此需要
    管理员鉴权(require_admin)。

    对每场已完赛比赛:
      1. 用比赛之前的数据构建上下文 (防未来信息泄漏,cutoff=match_date-1天)
      2. 调 LLM 预测(强制 use_cache=False,避免缓存命中导致反复 settle 同一行)
      3. 用实际比分回填(settle)
      4. 统计准确率 / RMSE / 校准度

    限流:单请求上限 200 场(默认 20),避免一次打爆 LLM 额度。
    回测写入 run_type='backtest',与实盘(live)互不覆盖(唯一键含 run_type)。
    """
    try:
        summary = await run_backtest(
            league_id=req.league_id,
            date_from=req.date_from,
            date_to=req.date_to,
            mode=req.mode,
            limit=req.limit,
            model=req.model,
        )
    except Exception as e:
        logger.exception("backtest failed")
        raise HTTPException(500, "回测执行失败,请查看服务器日志")

    return {
        "summary": {
            "total": summary.total,
            "scored": summary.scored,
            "success": summary.success,
            "degraded": summary.degraded,
            "accuracy_1x2": summary.accuracy_1x2,
            "avg_score_rmse": summary.avg_score_rmse,
            "avg_subjective_confidence": summary.avg_subjective_confidence,
        },
        "results": [
            {
                "match_id": r.match_id,
                "league_code": r.league_code,
                "home_team": r.home_team,
                "away_team": r.away_team,
                "home_team_zh": r.home_team_zh,
                "away_team_zh": r.away_team_zh,
                "match_date": r.match_date,
                "actual_score": f"{r.actual_home}-{r.actual_away}",
                "actual_1x2": r.actual_1x2,
                "pred_home": r.pred_home,
                "pred_away": r.pred_away,
                "pred_1x2": r.pred_1x2,
                "subjective_confidence": r.subjective_confidence,
                "correct_1x2": r.correct_1x2,
            }
            for r in summary.results
        ],
    }