"""Chart API（v3 §20.2）：统一可视化数据只读接口。

- GET /api/stocks/{symbol}/chart?start&end&adjust   K 线 + 量 + 指标（显示层折算）
- GET /api/stocks/{symbol}/signals                 该股历史信号（markers）
- GET /api/stocks/{symbol}/selections              该股历史选股命中（markers）
- GET /api/backtests/{experiment_id}/stocks/{symbol}/chart   回测个股：K 线 + 实际成交 fills
- GET /api/backtests/{experiment_id}/trades|positions        回测成交/持仓展开
"""

from __future__ import annotations

from datetime import date
from typing import Annotated

from fastapi import APIRouter, HTTPException, Query

from app.api.deps import (
    ChartServiceDep,
    ExperimentRepoDep,
    SelectionRepoDep,
    SignalRepoDep,
)
from app.domain.entities.chart import ChartResult, EventMarker, SelectionHit
from app.domain.entities.research import BacktestResult
from app.domain.entities.signal import SignalHit

router = APIRouter(tags=["charts"])

_AdjustQuery = Annotated[str, Query(pattern="^(none|qfq|hfq)$")]
_StartQuery = Annotated[date | None, Query(description="开始日期（默认 2024-01-01）")]
_EndQuery = Annotated[date | None, Query(description="结束日期（默认今天）")]


def _signal_markers(hits: list[SignalHit]) -> list[EventMarker]:
    kind_map = {"BUY": "signal_buy", "SELL": "signal_sell", "WATCH": "signal_watch"}
    return [
        EventMarker(
            time=h.signal_date,
            kind=kind_map.get(h.signal_type, "signal_watch"),
            symbol="",
            price=h.price,
            score=h.score,
            text=h.trigger_reason,
            ref_id=h.signal_id,
        )
        for h in hits
    ]


def _selection_markers(hits: list[SelectionHit]) -> list[EventMarker]:
    return [
        EventMarker(
            time=h.as_of,
            kind="selection",
            symbol=h.symbol,
            score=h.score,
            text=[f"rank #{h.rank}"] + h.selection_reason,
            ref_id=h.selection_id,
        )
        for h in hits
    ]


@router.get("/stocks/{symbol}/chart", response_model=ChartResult, summary="个股 K 线图数据")
def stock_chart(
    symbol: str,
    service: ChartServiceDep,
    start: _StartQuery = None,
    end: _EndQuery = None,
    adjust: _AdjustQuery = "none",
) -> ChartResult:
    start = start or date(2024, 1, 1)
    end = end or date.today()
    if service.stock(symbol) is None:
        raise HTTPException(status_code=404, detail=f"未找到股票 {symbol}")
    return service.stock_chart(symbol, start, end, adjust)


@router.get("/stocks/{symbol}/signals", response_model=list[EventMarker], summary="该股历史信号")
def symbol_signals(symbol: str, signal_repo: SignalRepoDep) -> list[EventMarker]:
    return _signal_markers(signal_repo.list_by_symbol(symbol))


@router.get("/stocks/{symbol}/selections", response_model=list[EventMarker], summary="该股历史选股命中")
def symbol_selections(symbol: str, selection_repo: SelectionRepoDep) -> list[EventMarker]:
    return _selection_markers(selection_repo.list_by_symbol(symbol))


@router.get(
    "/backtests/{experiment_id}/stocks/{symbol}/chart",
    response_model=ChartResult,
    summary="回测个股图（K 线 + 实际成交 fills）",
)
def backtest_stock_chart(
    experiment_id: str,
    symbol: str,
    service: ChartServiceDep,
    experiment_repo: ExperimentRepoDep,
    start: _StartQuery = None,
    end: _EndQuery = None,
    adjust: _AdjustQuery = "none",
) -> ChartResult:
    start = start or date(2024, 1, 1)
    end = end or date.today()
    exp = experiment_repo.get(experiment_id)
    if exp is None:
        raise HTTPException(status_code=404, detail=f"Experiment {experiment_id} 不存在")
    try:
        result = BacktestResult.model_validate_json(exp.result_json)
    except Exception as exc:  # noqa: BLE001
        raise HTTPException(status_code=400, detail=f"{experiment_id} 不是 backtest 结果") from exc
    return service.backtest_stock_chart(result, symbol, start, end, adjust)


@router.get("/backtests/{experiment_id}/trades", summary="回测成交明细")
def backtest_trades(experiment_id: str, experiment_repo: ExperimentRepoDep):
    exp = experiment_repo.get(experiment_id)
    if exp is None:
        raise HTTPException(status_code=404, detail=f"Experiment {experiment_id} 不存在")
    result = BacktestResult.model_validate_json(exp.result_json)
    return result.trades


@router.get("/backtests/{experiment_id}/positions", summary="回测持仓明细")
def backtest_positions(experiment_id: str, experiment_repo: ExperimentRepoDep):
    exp = experiment_repo.get(experiment_id)
    if exp is None:
        raise HTTPException(status_code=404, detail=f"Experiment {experiment_id} 不存在")
    result = BacktestResult.model_validate_json(exp.result_json)
    return result.positions