/**
 * 가상투자 — 종목별 STOMP 실시간 데이터 수신 상태
 */
import { useEffect, useRef, useState } from 'react';
import { pinCandleWatch } from '../utils/backendApi';
import { parseStompJson } from '../utils/stompMessage';
import {
  isStompChartConnected,
  subscribeStompConnection,
  subscribeStompTopic,
} from '../utils/stompChartBroker';

/** idle=미시작, connecting=연결 중, live=틱 수신 중, disconnected=끊김 */
export type VirtualLiveStatus = 'idle' | 'connecting' | 'live' | 'disconnected';

const STALE_MS = 20_000;
/** useStompChartData 와 동일 — STOMP 수립 후 틱 없어도 실시간 파이프라인 준비 완료로 간주 */
const CONN_GRACE_MS = 800;
const TICK_CANDLE = '1m';

interface TargetRef {
  market: string;
  strategyId: number | null;
}

interface MarketLiveState {
  status: VirtualLiveStatus;
  lastTickAt: number | null;
}

function topicFor(market: string): string {
  return `/sub/charts/${market}/${TICK_CANDLE}`;
}

function isCandlePayload(data: { time?: unknown; close?: unknown } | null): boolean {
  if (!data) return false;
  return typeof data.time === 'number' || typeof data.close === 'number';
}

/** 목록·카드에서 liveStatusByMarket 미등록 시 fallback */
export function resolveVirtualLiveStatusFallback(
  market: string,
  strategyId: number | null,
  statusByMarket: Record<string, VirtualLiveStatus>,
  running: boolean,
): VirtualLiveStatus {
  const known = statusByMarket[market];
  if (known) return known;
  if (!strategyId) return 'idle';
  return running ? 'connecting' : 'idle';
}

export interface VirtualTargetLiveState {
  statusByMarket: Record<string, VirtualLiveStatus>;
  /** STOMP 틱 수신 시각 (ms) — 카드 형광 플래시 트리거 */
  lastTickAtByMarket: Record<string, number>;
}

export function useVirtualTargetLiveStatus(
  targets: TargetRef[],
  running: boolean,
  /** 전략 지정만 된 상태에서도 STOMP·pin으로 업비트 틱 수신 (지표 warm-up 보조) */
  eagerConnect = true,
): VirtualTargetLiveState {
  const [byMarket, setByMarket] = useState<Record<string, VirtualLiveStatus>>({});
  const [lastTickAtByMarket, setLastTickAtByMarket] = useState<Record<string, number>>({});
  const stateRef = useRef<Record<string, MarketLiveState>>({});
  const stompConnectedRef = useRef(isStompChartConnected());
  const stompConnectedAtRef = useRef<number | null>(
    isStompChartConnected() ? Date.now() : null,
  );

  const patchMarket = (market: string, patch: Partial<MarketLiveState>) => {
    const prev = stateRef.current[market] ?? { status: 'idle' as VirtualLiveStatus, lastTickAt: null };
    const next: MarketLiveState = { ...prev, ...patch };
    stateRef.current[market] = next;
    setByMarket(cur => ({ ...cur, [market]: next.status }));
    if (patch.lastTickAt != null) {
      setLastTickAtByMarket(cur => ({ ...cur, [market]: patch.lastTickAt! }));
    }
  };

  const recomputeStatus = (market: string) => {
    const s = stateRef.current[market];
    if (!s) return;
    const now = Date.now();
    if (s.lastTickAt != null && now - s.lastTickAt <= STALE_MS) {
      if (s.status !== 'live') patchMarket(market, { status: 'live' });
      return;
    }
    if (stompConnectedRef.current) {
      const connectedAt = stompConnectedAtRef.current;
      if (connectedAt != null && now - connectedAt >= CONN_GRACE_MS) {
        patchMarket(market, { status: 'live' });
        return;
      }
      patchMarket(market, { status: 'connecting' });
    } else {
      patchMarket(market, { status: 'disconnected' });
    }
  };

  const targetsKey = targets
    .filter(t => t.strategyId != null)
    .map(t => `${t.market}:${t.strategyId}`)
    .join('|');

  useEffect(() => {
    const activeMarkets = targets
      .filter(t => t.strategyId != null)
      .map(t => t.market);

    const active = running || (eagerConnect && activeMarkets.length > 0);
    if (!active) {
      stateRef.current = {};
      setByMarket({});
      setLastTickAtByMarket({});
      return;
    }

    for (const market of activeMarkets) {
      if (!stateRef.current[market]) {
        stateRef.current[market] = { status: 'connecting', lastTickAt: null };
        setByMarket(cur => ({ ...cur, [market]: 'connecting' }));
      }
      void pinCandleWatch(market, TICK_CANDLE);
    }

    for (const key of Object.keys(stateRef.current)) {
      if (!activeMarkets.includes(key)) {
        delete stateRef.current[key];
        setByMarket(cur => {
          const next = { ...cur };
          delete next[key];
          return next;
        });
        setLastTickAtByMarket(cur => {
          const next = { ...cur };
          delete next[key];
          return next;
        });
      }
    }

    const unsubs = activeMarkets.map(market => {
      const topic = topicFor(market);
      return subscribeStompTopic(topic, msg => {
        const data = parseStompJson<{ time?: number; close?: number }>(msg);
        if (!isCandlePayload(data)) return;
        patchMarket(market, { status: 'live', lastTickAt: Date.now() });
      });
    });

    let graceTimer: ReturnType<typeof setTimeout> | null = null;
    const scheduleGraceRecompute = () => {
      if (graceTimer) clearTimeout(graceTimer);
      if (!stompConnectedRef.current) return;
      graceTimer = setTimeout(() => {
        for (const market of activeMarkets) recomputeStatus(market);
      }, CONN_GRACE_MS);
    };

    const offConn = subscribeStompConnection(next => {
      stompConnectedRef.current = next;
      stompConnectedAtRef.current = next ? Date.now() : null;
      for (const market of activeMarkets) recomputeStatus(market);
      if (next) scheduleGraceRecompute();
    });

    if (stompConnectedRef.current) scheduleGraceRecompute();

    const staleId = window.setInterval(() => {
      for (const market of activeMarkets) recomputeStatus(market);
    }, 3000);

    return () => {
      unsubs.forEach(u => u());
      offConn();
      clearInterval(staleId);
      if (graceTimer) clearTimeout(graceTimer);
    };
  }, [targetsKey, running, eagerConnect]);

  return { statusByMarket: byMarket, lastTickAtByMarket };
}