"use client";

/** Stock Research Page（v3 §20.4）：单只股票的统一研究视图。
 * K 线（chart API，可切换不复权/前复权显示）+ 成交量 + MA +
 * 该股成交（fills）与未成交信号（signals）标记 + 最近选股/信号历史（点击看原因）。
 * 全部数据来自 Chart API —— 前端不重算。
 */
import { useEffect, useMemo, useState } from "react";
import { useParams } from "next/navigation";
import { apiGet } from "@/lib/api";
import type { ChartMarker, ChartResult, Stock } from "@/lib/types";
import {
  PageHeader,
  Card,
  Pill,
  Btn,
  Banner,
  Empty,
  SkeletonLines,
} from "@/components/ui";
import type { CandleDatum } from "@/components/StockChart/chartTypes";
import { StockChart, type ChartLibrary } from "@/components/StockChart/StockChart";

export default function StockResearchPage() {
  const params = useParams<{ symbol: string }>();
  const symbol = (params.symbol ?? "").toUpperCase();
  const [stock, setStock] = useState<Stock | null>(null);
  const [chart, setChart] = useState<ChartResult | null>(null);
  const [signalMarkers, setSignalMarkers] = useState<ChartMarker[]>([]);
  const [selectionMarkers, setSelectionMarkers] = useState<ChartMarker[]>([]);
  const [adjust, setAdjust] = useState<"none" | "qfq" | "hfq">("none");
  const [chartLib, setChartLib] = useState<ChartLibrary>("lightweight");
  const [loading, setLoading] = useState(true);
  const [error, setError] = useState("");

  useEffect(() => {
    let alive = true;
    setLoading(true);
    setError("");
    Promise.all([
      apiGet<Stock>(`/stocks/${symbol}`),
      apiGet<ChartResult>(`/stocks/${symbol}/chart?adjust=${adjust}`),
      apiGet<ChartMarker[]>(`/stocks/${symbol}/signals`),
      apiGet<ChartMarker[]>(`/stocks/${symbol}/selections`),
    ])
      .then(([st, ch, sig, sel]) => {
        if (!alive) return;
        setStock(st);
        setChart(ch);
        setSignalMarkers(sig);
        setSelectionMarkers(sel);
      })
      .catch((e: Error) => alive && setError(e.message))
      .finally(() => alive && setLoading(false));
    return () => {
      alive = false;
    };
  }, [symbol, adjust]);

  const candles: CandleDatum[] = useMemo(
    () =>
      (chart?.bars ?? [])
        .filter((b) => b.open != null && b.close != null && b.low != null && b.high != null)
        .map((b) => ({
          time: b.time,
          open: b.open as number,
          close: b.close as number,
          low: b.low as number,
          high: b.high as number,
        })),
    [chart]
  );

  return (
    <>
      <PageHeader
        title={stock ? `${stock.name} ${stock.symbol}` : symbol}
        sub={
          stock
            ? `行业 ${stock.industry ?? "-"} · 市场 ${stock.market ?? "-"} · 上市 ${stock.list_date} · 状态 ${stock.status}`
            : "个股研究视图（K 线 / 信号 / 成交）"
        }
        actions={
          <div className="row" style={{ gap: 6 }}>
            {(["echarts", "lightweight"] as const).map((l) => (
              <Btn key={l} variant={chartLib === l ? "primary" : undefined} onClick={() => setChartLib(l)}>
                {l === "echarts" ? "ECharts" : "Lightweight"}
              </Btn>
            ))}
            {(["none", "qfq", "hfq"] as const).map((m) => (
              <Btn
                key={m}
                variant={adjust === m ? "primary" : undefined}
                onClick={() => setAdjust(m)}
              >
                {m === "none" ? "不复权" : m === "qfq" ? "前复权" : "后复权"}
              </Btn>
            ))}
          </div>
        }
      />

      {error ? <Banner tone="error">{error}</Banner> : null}
      {loading && !chart ? (
        <SkeletonLines n={8} />
      ) : (
        <>
          <Card
            icon="chartLine"
            title={`K 线 · ${chart?.metadata.adjust_mode ?? "-"} · ${chart?.metadata.name ?? ""}`}
            tools={
              <>
                <Pill>共 {chart?.metadata.bar_count ?? 0} 根</Pill>
                {chart?.metadata.execution_price_basis ? (
                  <Pill tone="violet">回测执行价口径 {chart.metadata.execution_price_basis}</Pill>
                ) : null}
              </>
            }
          >
            {candles.length === 0 ? (
              <Empty icon="chartLine" title="无 K 线数据" hint="该区间/口径没有行情（可能停牌或未同步）。" />
            ) : (
              <StockChart
                library={chartLib}
                data={candles}
                volume={chart?.volume ?? []}
                indicators={chart?.indicators ?? {}}
                fills={chart?.fills ?? []}
                signals={chart?.signals ?? []}
                name={symbol}
              />
            )}
          </Card>

          {chart && (chart.signals.length || chart.fills.length) ? (
            <Card
              icon="scale"
              title={`回测成交与信号 · ${symbol}`}
              tools={
                <>
                  <Pill tone="pos">成交 {chart.fills.length}</Pill>
                  <Pill>未成交信号 {chart.signals.length}</Pill>
                </>
              }
            >
              <div className="chips">
                {[...chart.signals, ...chart.fills].map((m, i) => (
                  <span className="chip" key={`${m.kind}-${m.time}-${i}`} title={m.text.join("；")}>
                    <b className="mono">{m.time}</b>
                    {m.kind}
                    {m.price ? ` @${m.price}` : ""}
                  </span>
                ))}
              </div>
            </Card>
          ) : null}

          <div className="chart-grid">
            <Card icon="spark" title="该股历史选股命中">
              {selectionMarkers.length === 0 ? (
                <Empty icon="spark" title="暂无选股记录" hint="该股尚未进入任何落库选股结果。" />
              ) : (
                <div className="chips">
                  {selectionMarkers.slice(0, 12).map((m, i) => (
                    <span className="chip" key={`sel-${m.time}-${i}`} title={m.text.join("；")}>
                      <b className="mono">{m.time}</b>
                      {m.text[0]}
                    </span>
                  ))}
                </div>
              )}
            </Card>
            <Card icon="alert" title="该股历史信号">
              {signalMarkers.length === 0 ? (
                <Empty icon="alert" title="暂无信号记录" />
              ) : (
                <div className="chips">
                  {signalMarkers.slice(0, 12).map((m, i) => (
                    <span className="chip" key={`sig-${m.time}-${i}`} title={m.text.join("；")}>
                      <b className="mono">{m.time}</b>
                      {m.kind}
                      {m.price ? ` @${m.price}` : ""}
                    </span>
                  ))}
                </div>
              )}
            </Card>
          </div>
        </>
      )}
    </>
  );
}