"""数据 API 路由 - 批量获取/最新数据/缓存状态"""

import logging
from datetime import datetime

from fastapi import APIRouter, Depends, HTTPException
from sqlalchemy import select
from sqlalchemy.ext.asyncio import AsyncSession

from app.config import settings
from app.database import get_db
from app.models.market import SymbolTimestamp
from app.schemas import (
    BatchFetchRequest,
    BatchFetchResponse,
    CandleItem,
    SymbolDataResponse,
    TimeframeData,
)
from app.services.cache import (
    check_cache_status,
    get_cached_data,
    get_latest_cached,
    save_market_data,
)
from app.services.collector import fetch_symbol_data

logger = logging.getLogger(__name__)
router = APIRouter(prefix="/data", tags=["数据"])


def _normalize_candles(candles: list[dict]) -> list[dict]:
    """将K线数据中的 time 字段统一为 datetime。"""
    normalized = []
    for c in candles:
        candle_dict = dict(c)
        if "time" in candle_dict and "datetime" not in candle_dict:
            candle_dict["datetime"] = candle_dict.pop("time")
        normalized.append(candle_dict)
    return normalized


def _build_timeframes(
    timeframes_dict: dict[str, list],
    periods: list[str],
    fetched_at: str,
) -> list[TimeframeData]:
    """从 timeframes 字典构建 TimeframeData 列表。"""
    result = []
    for p in periods:
        candles = timeframes_dict.get(p, [])
        if candles:
            normalized = _normalize_candles(candles)
            result.append(
                TimeframeData(
                    period=p,
                    candles=[CandleItem(**c) for c in normalized],
                    candle_count=len(normalized),
                    fetched_at=fetched_at,
                )
            )
    return result


@router.post("/batch-fetch", response_model=BatchFetchResponse)
async def batch_fetch(
    req: BatchFetchRequest,
    db: AsyncSession = Depends(get_db),
):
    """批量获取指定品种、指定周期的数据（智能缓存）。"""
    symbols = req.symbols
    periods = req.periods
    data_type = req.data_type

    success: list[str] = []
    failed: list[str] = []
    details: dict = {}

    for sym in symbols:
        cache_status = await check_cache_status(db, sym, data_type, periods)

        if cache_status["all_valid"]:
            logger.info("[%s] 缓存全部命中，跳过采集", sym)
            cached = await get_cached_data(db, sym, data_type, periods)
            timeframes = _build_timeframes(
                cached["timeframes"], periods, cached.get("timestamp", "")
            )
            details[sym] = SymbolDataResponse(
                symbol=sym,
                data_type=data_type,
                current_price=cached.get("current_price"),
                timeframes=timeframes,
                source="cache",
            )
            success.append(sym)
            continue

        need_fetch = cache_status["missing_periods"]
        logger.info("[%s] 缓存部分缺失，需要采集: %s", sym, need_fetch)

        result = await fetch_symbol_data(sym, data_type, need_fetch)

        if result and result.get("timeframes"):
            await save_market_data(db, sym, result)
            success.append(sym)

            all_timeframes: dict[str, list] = {}
            if cache_status["valid_periods"]:
                existing = await get_cached_data(
                    db, sym, data_type, cache_status["valid_periods"]
                )
                if existing:
                    all_timeframes.update(existing["timeframes"])
            all_timeframes.update(result["timeframes"])

            timeframes = _build_timeframes(
                all_timeframes, periods, result.get("timestamp", "")
            )
            details[sym] = SymbolDataResponse(
                symbol=sym,
                data_type=data_type,
                current_price=result.get("current_price"),
                timeframes=timeframes,
                source="live+cache",
            )
        else:
            failed.append(sym)
            details[sym] = {"error": (result or {}).get("error", "未知错误")}

    return BatchFetchResponse(success=success, failed=failed, details=details)


@router.get("/latest/{symbol}", response_model=SymbolDataResponse)
async def get_latest(
    symbol: str,
    data_type: str = "futures",
    period: str | None = None,
    end_time: str | None = None,
    db: AsyncSession = Depends(get_db),
):
    """从缓存获取最新数据。"""
    end_dt = None
    if end_time:
        try:
            end_dt = datetime.fromisoformat(end_time)
        except Exception as e:
            raise HTTPException(status_code=400, detail=f"end_time 格式错误: {e}") from e

    try:
        cached = await get_cached_data(
            db, symbol, data_type, [period] if period else None, end_time=end_dt
        )
        if not cached:
            raise HTTPException(status_code=404, detail=f"未找到 {symbol} 的缓存数据")

        period_keys = list(cached["timeframes"].keys())
        timeframes = _build_timeframes(
            cached["timeframes"], period_keys, cached.get("timestamp", "")
        )

        return SymbolDataResponse(
            symbol=symbol,
            data_type=data_type,
            current_price=cached.get("current_price"),
            timeframes=timeframes,
            source="cache" if cached.get("is_fresh", False) else "cache_stale",
        )
    except HTTPException:
        raise
    except Exception as e:
        logger.error("获取数据失败: symbol=%s, error=%s", symbol, e)
        raise HTTPException(status_code=500, detail=f"服务器内部错误: {e}") from e


@router.get("/latest/{symbol}/{period}")
async def get_latest_by_period(
    symbol: str,
    period: str,
    data_type: str = "futures",
    db: AsyncSession = Depends(get_db),
):
    """获取缓存中指定品种+周期的最新数据。"""
    cached = await get_cached_data(db, symbol, data_type, [period])
    if not cached:
        raise HTTPException(status_code=404, detail=f"未找到 {symbol} {period} 的缓存")

    candles = cached["timeframes"].get(period, [])
    return {
        "symbol": symbol,
        "period": period,
        "data_type": data_type,
        "candles": candles,
        "candle_count": len(candles),
        "current_price": cached.get("current_price"),
        "fetched_at": cached.get("timestamp"),
        "is_fresh": cached.get("is_fresh", False),
    }


@router.get("/cache-status/{symbol}")
async def cache_status(
    symbol: str,
    db: AsyncSession = Depends(get_db),
):
    """查看品种的缓存状态。"""
    records = await get_latest_cached(db, symbol)
    if not records:
        return {"symbol": symbol, "cached_periods": [], "status": "no_data"}

    now = datetime.now()
    periods_info = []
    for r in records:
        age_seconds = (now - r.fetched_at).total_seconds()
        periods_info.append({
            "period": r.period,
            "candle_count": r.candle_count,
            "fetched_at": r.fetched_at.isoformat(),
            "age_seconds": round(age_seconds, 0),
            "is_fresh": age_seconds < settings.cache_ttl_seconds,
        })

    return {
        "symbol": symbol,
        "cached_periods": periods_info,
        "status": "ok",
    }


@router.get("/latest-timestamps")
async def get_latest_timestamps(
    db: AsyncSession = Depends(get_db),
):
    """获取所有品种的最新数据时间戳。"""
    stmt = select(SymbolTimestamp)
    result = await db.execute(stmt)
    timestamps = list(result.scalars().all())

    data = []
    for ts in timestamps:
        data.append({
            "symbol": ts.symbol,
            "data_type": ts.data_type,
            "last_refresh_at": ts.last_refresh_at.isoformat() if ts.last_refresh_at else None,
        })

    return {"success": True, "data": data}