/**
 * 분석레포트 — 좌: 백테스팅/실시간 목록(백테스팅 화면과 동일) · 우: PDF 10 Variations 탭
 */
import React, { useCallback, useEffect, useMemo, useRef, useState } from 'react';
import type { Theme } from '../../types';
import {
  loadBacktestResults,
  loadPaperTrades,
  loadPaperSummary,
  loadStrategies,
  type BacktestResultRecord,
  type StrategyDto,
} from '../../utils/backendApi';
import type { AnalysisReportTypeId } from '../../utils/analysisReportTypes';
import { ANALYSIS_REPORT_TYPES } from '../../utils/analysisReportTypes';
import {
  buildContextFromBacktest,
  buildContextFromLive,
} from '../../utils/analysisReportContext';
import { buildLiveExecutionItems, type LiveExecutionItem } from '../../utils/liveExecutionGroups';
import { PAPER_TRADES_CHANGED_EVENT } from '../../utils/paperTradeEvents';
import {
  readStoredSize,
  storeSize,
  usePanelResize,
} from '../strategyEditor/usePanelResize';
import BacktestExecutionList, { type ExecutionListTab } from '../backtest/BacktestExecutionList';
import AnalysisReportViews from './AnalysisReportViews';
import BacktestAnalysisReportModal from '../backtest/BacktestAnalysisReportModal';
import {
  buildBacktestReportModel,
  buildLiveReportModel,
} from '../../utils/backtestReportModel';
import '../../styles/strategyEditorTheme.css';
import '../../styles/backtestDashboard.css';
import '../../styles/analysisReportPage.css';

const LEFT_KEY = 'arp-left-width';
const LEFT_DEFAULT = 380;

interface Props {
  theme?: Theme;
}

function pickCompareBacktest(
  selected: BacktestResultRecord,
  records: BacktestResultRecord[],
): BacktestResultRecord | null {
  const others = records.filter(r => r.id !== selected.id);
  const sameSymbol = others.filter(r => r.symbol === selected.symbol);
  return sameSymbol[0] ?? others[0] ?? null;
}

export function AnalysisReportPage({ theme = 'dark' }: Props) {
  const [reportTypeId, setReportTypeId] = useState<AnalysisReportTypeId>('standard');
  const [sourceTab, setSourceTab] = useState<ExecutionListTab>('backtest');
  const [records, setRecords] = useState<BacktestResultRecord[]>([]);
  const [liveItems, setLiveItems] = useState<LiveExecutionItem[]>([]);
  const [selectedBacktest, setSelectedBacktest] = useState<BacktestResultRecord | null>(null);
  const [selectedLive, setSelectedLive] = useState<LiveExecutionItem | null>(null);
  const [strategies, setStrategies] = useState<StrategyDto[]>([]);
  const [loading, setLoading] = useState(true);
  const [reportOpen, setReportOpen] = useState(false);

  const [leftWidth, setLeftWidth] = useState(() => Math.max(readStoredSize(LEFT_KEY, LEFT_DEFAULT), 300));
  const leftRef = useRef(leftWidth);
  leftRef.current = leftWidth;
  const onLeftSplit = usePanelResize('vertical', setLeftWidth, () => leftRef.current, 300, 520, v => storeSize(LEFT_KEY, v));

  const refreshLive = useCallback(async () => {
    const [trades, summary, stratList] = await Promise.all([
      loadPaperTrades(),
      loadPaperSummary(),
      loadStrategies(),
    ]);
    setStrategies(stratList);
    const strategyNames = Object.fromEntries(stratList.map(s => [s.id, s.name]));
    const live = buildLiveExecutionItems(trades, summary, strategyNames);
    setLiveItems(live);
    setSelectedLive(prev => (prev && live.some(x => x.id === prev.id) ? prev : live[0] ?? null));
  }, []);

  const fetchAll = useCallback(async () => {
    setLoading(true);
    try {
      const [recs, stratList] = await Promise.all([
        loadBacktestResults(),
        loadStrategies(),
      ]);
      setRecords(recs);
      setStrategies(stratList);
      setSelectedBacktest(prev => (prev && recs.some(r => r.id === prev.id) ? prev : recs[0] ?? null));
      await refreshLive();
    } finally {
      setLoading(false);
    }
  }, [refreshLive]);

  useEffect(() => { void fetchAll(); }, [fetchAll]);
  useEffect(() => {
    const onPaper = () => { void refreshLive(); };
    window.addEventListener(PAPER_TRADES_CHANGED_EVENT, onPaper);
    return () => window.removeEventListener(PAPER_TRADES_CHANGED_EVENT, onPaper);
  }, [refreshLive]);

  const compareBacktest = useMemo(() => {
    if (!selectedBacktest) return null;
    return pickCompareBacktest(selectedBacktest, records);
  }, [records, selectedBacktest]);

  const compareLive = useMemo(() => {
    if (!selectedLive) return null;
    return liveItems.find(x => x.id !== selectedLive.id) ?? null;
  }, [liveItems, selectedLive]);

  const ctx = useMemo(() => {
    if (sourceTab === 'backtest' && selectedBacktest) {
      return buildContextFromBacktest(selectedBacktest, compareBacktest);
    }
    if (sourceTab === 'live' && selectedLive) {
      return buildContextFromLive(selectedLive);
    }
    return null;
  }, [sourceTab, selectedBacktest, selectedLive, compareBacktest]);

  const strategyNamesById = useMemo(
    () => Object.fromEntries(strategies.map(s => [s.id, s.name])),
    [strategies],
  );

  const reportModel = useMemo(() => {
    if (sourceTab === 'backtest' && selectedBacktest && ctx?.analysis) {
      return buildBacktestReportModel(
        selectedBacktest,
        ctx.analysis,
        ctx.signals,
        strategyNamesById,
      );
    }
    if (sourceTab === 'live' && selectedLive) {
      return buildLiveReportModel(selectedLive, ctx?.signals ?? [], '1h');
    }
    return null;
  }, [sourceTab, selectedBacktest, selectedLive, ctx, strategyNamesById]);

  if (loading) {
    return (
      <div className={`arp-page se-page se-page--${theme}`}>
        <header className="arp-header">
          <h1 className="arp-header-title">분석레포트</h1>
        </header>
        <div className="arp-loading">데이터 로딩…</div>
      </div>
    );
  }

  return (
    <div className={`arp-page se-page se-page--${theme}`}>
      <header className="arp-header">
        <div className="arp-header-brand">
          <h1 className="arp-header-title">분석레포트</h1>
          <span className="arp-header-sub">TradingReport UI Design · 10 Variations</span>
        </div>
        <div className="arp-header-actions">
          <button type="button" className="arp-btn" onClick={() => void fetchAll()}>새로고침</button>
          <button
            type="button"
            className="arp-btn arp-btn--gold"
            disabled={!reportModel}
            onClick={() => setReportOpen(true)}
          >
            인쇄 / PDF
          </button>
        </div>
      </header>

      <div className="arp-body">
        <aside
          className="arp-sidebar btd-sidebar"
          style={{ width: leftWidth, flex: `0 0 ${leftWidth}px` }}
        >
          <BacktestExecutionList
            tab={sourceTab}
            onTabChange={setSourceTab}
            backtestRecords={records}
            liveItems={liveItems}
            selectedBacktestId={selectedBacktest?.id ?? null}
            selectedLiveId={selectedLive?.id ?? null}
            onSelectBacktest={r => {
              setSelectedBacktest(r);
              setSourceTab('backtest');
            }}
            onSelectLive={item => {
              setSelectedLive(item);
              setSourceTab('live');
            }}
          />
        </aside>

        <div
          className="arp-splitter btd-splitter btd-splitter--v"
          role="separator"
          aria-orientation="vertical"
          aria-label="좌측 패널 너비"
          onPointerDown={onLeftSplit}
        />

        <main className="arp-main">
          <div className="arp-type-tabs" role="tablist" aria-label="레포트 유형">
            {ANALYSIS_REPORT_TYPES.map(t => (
              <button
                key={t.id}
                type="button"
                role="tab"
                aria-selected={reportTypeId === t.id}
                className={`arp-type-tab${reportTypeId === t.id ? ' arp-type-tab--on' : ''}`}
                title={t.subtitle}
                onClick={() => setReportTypeId(t.id)}
              >
                <span className="arp-type-tab-num">{t.tabLabel.split(' ')[0]}</span>
                <span className="arp-type-tab-name">{t.tabLabel.replace(/^\d+\s*/, '')}</span>
              </button>
            ))}
          </div>
          <div className="arp-viewport">
            <AnalysisReportViews
              typeId={reportTypeId}
              ctx={ctx}
              theme={theme}
              allBacktests={records}
              compareBacktest={compareBacktest}
              compareLive={compareLive}
            />
          </div>
        </main>
      </div>

      <BacktestAnalysisReportModal
        open={reportOpen}
        onClose={() => setReportOpen(false)}
        model={reportModel}
      />
    </div>
  );
}

export default AnalysisReportPage;