'use client';

import { useCallback, useEffect, useMemo, useState } from 'react';
import { useHasPermission } from '@/components/auth/Guard';
import { useAuthStore } from '@/stores/useAuthStore';
import { useBugStore } from '@/stores/useBugStore';
import { useDevTaskStore } from '@/stores/useDevTaskStore';
import { useProductStore } from '@/stores/useProductStore';
import { useRequirementStore } from '@/stores/useRequirementStore';
import { useTaskWorklogStore } from '@/stores/useTaskWorklogStore';
import { useTestCaseStore } from '@/stores/useTestCaseStore';
import { useVersionPlanStore } from '@/stores/useVersionPlanStore';
import { useWorkActivityStore } from '@/stores/useWorkActivityStore';
import { useXiaobaoRiskStore } from '@/stores/useXiaobaoRiskStore';
import { flattenVersions } from '@/lib/derive';
import { loadV22XiaobaoWarnings, type V22XiaobaoWarningSummary } from '@/lib/v22-api';
import { buildVersionDataScopeMap } from '@/lib/version-data-scope';
import {
  buildXiaobaoRisksFromV22Summaries,
  collectV22XiaobaoLatestInsights,
  filterV22XiaobaoSummariesForVisibleVersions,
  mergeV22XiaobaoLatestInsights,
  shouldLoadXiaobaoStoreFallback,
  type V22XiaobaoSummaryLoadState,
} from '@/lib/xiaobao-v22-summary';
import { calcXiaobaoVersionRisk } from '@/lib/xiaobao-risk';
import { buildVersionDailyEvidence, buildXiaobaoWorkItems } from '@/lib/xiaobao-risk-evidence';
import { filterXiaobaoWarningVersions } from '@/lib/xiaobao-warning-view';

export function useXiaobaoWarningRisks({ loadRiskCache = false }: { loadRiskCache?: boolean } = {}) {
  const canManage = useHasPermission('xiaobao.warning:manage');
  const user = useAuthStore((s) => s.user);
  const { overview, fetchOverview } = useProductStore();
  const { plans, fetchPlans } = useVersionPlanStore();
  const { requirements, fetchRequirements } = useRequirementStore();
  const { tasks: devTasks, fetchTasks } = useDevTaskStore();
  const { testCases, fetchTestCases } = useTestCaseStore();
  const { bugs, fetchBugs } = useBugStore();
  const { activities, fetchActivities } = useWorkActivityStore();
  const { worklogs, fetchWorklogs } = useTaskWorklogStore();
  const {
    snapshots,
    insights,
    pendingInsightKeys,
    insightRequestAttempts,
    riskDataLoaded,
    fetchRiskData,
    saveSnapshot,
    saveInsight,
    beginInsightUpdate,
    finishInsightUpdate,
  } = useXiaobaoRiskStore();
  const [calculationNow] = useState(() => new Date());
  const [v22SummaryState, setV22SummaryState] = useState<V22XiaobaoSummaryLoadState>('idle');
  const [v22Summaries, setV22Summaries] = useState<V22XiaobaoWarningSummary[]>([]);
  const today = useMemo(() => new Date().toISOString().slice(0, 10), []);
  const v22UserId = user?.name || user?.id || '';
  const shouldLoadFallback = shouldLoadXiaobaoStoreFallback(v22SummaryState);
  const relationInsights = useMemo(() => collectV22XiaobaoLatestInsights(v22Summaries), [v22Summaries]);
  const mergedInsights = useMemo(
    () => mergeV22XiaobaoLatestInsights(relationInsights, insights),
    [insights, relationInsights],
  );
  const allVersions = useMemo(() => flattenVersions(overview), [overview]);
  const visibleVersions = useMemo(
    () => filterXiaobaoWarningVersions(allVersions, { canManage, userName: user?.name }),
    [allVersions, canManage, user?.name],
  );
  const hydrateXiaobaoStoreFallback = useCallback(() => {
    for (const version of visibleVersions) {
      void fetchRequirements({ productId: version.productId, versionId: version.id });
      void fetchPlans({ versionId: version.id });
      void fetchTasks({ versionId: version.id });
      void fetchTestCases({ versionId: version.id });
      void fetchBugs({ versionId: version.id });
    }
  }, [fetchBugs, fetchPlans, fetchRequirements, fetchTasks, fetchTestCases, visibleVersions]);

  useEffect(() => { fetchOverview(); }, [fetchOverview]);
  useEffect(() => {
    if (!canManage && !v22UserId) {
      setV22SummaryState('idle');
      setV22Summaries([]);
      return;
    }

    let ignore = false;
    setV22SummaryState('loading');
    loadV22XiaobaoWarnings({
      userId: v22UserId || undefined,
      manager: canManage,
    }).then((summaries) => {
      if (ignore) return;
      setV22Summaries(summaries);
      setV22SummaryState(summaries.length > 0 ? 'ready' : 'empty');
    }).catch(() => {
      if (ignore) return;
      setV22Summaries([]);
      setV22SummaryState('failed');
    });

    return () => {
      ignore = true;
    };
  }, [canManage, v22UserId]);
  useEffect(() => {
    if (shouldLoadFallback) hydrateXiaobaoStoreFallback();
  }, [hydrateXiaobaoStoreFallback, shouldLoadFallback]);
  useEffect(() => { if (shouldLoadFallback) fetchActivities(); }, [fetchActivities, shouldLoadFallback]);
  useEffect(() => { if (shouldLoadFallback) fetchWorklogs(); }, [fetchWorklogs, shouldLoadFallback]);
  useEffect(() => {
    if (loadRiskCache) fetchRiskData();
  }, [fetchRiskData, loadRiskCache]);

  const visibleVersionScopeMap = useMemo(() => buildVersionDataScopeMap({
    versionIds: visibleVersions.map((version) => version.id),
    plans,
    requirements,
    devTasks,
    testCases,
    bugs,
  }), [bugs, devTasks, plans, requirements, testCases, visibleVersions]);

  const workItemsByVersion = useMemo(() => {
    const map = new Map<string, ReturnType<typeof buildXiaobaoWorkItems>>();
    for (const version of visibleVersions) {
      const scope = visibleVersionScopeMap[version.id];
      if (!scope) continue;
      map.set(version.id, buildXiaobaoWorkItems({
        plans: scope.plans,
        devTasks: scope.devTasks,
        testCases: scope.testCases,
        bugs: scope.bugs,
        versions: [{
          id: version.id,
          name: version.name,
          productName: version.productName,
          projectName: version.projectName,
        }],
        requirementVersionMap: new Map(scope.requirements.map((requirement) => [requirement.id, version.id])),
      }));
    }
    return map;
  }, [visibleVersionScopeMap, visibleVersions]);

  const risks = useMemo(() => {
    if (v22SummaryState === 'ready') {
      return buildXiaobaoRisksFromV22Summaries({
        summaries: filterV22XiaobaoSummariesForVisibleVersions(v22Summaries, visibleVersions),
        versions: visibleVersions,
        snapshots,
        now: calculationNow,
      });
    }

    return visibleVersions.map((version) => {
      const scope = visibleVersionScopeMap[version.id];
      const workItems = workItemsByVersion.get(version.id) ?? [];
      const dailyEvidence = buildVersionDailyEvidence({
        versionId: version.id,
        workItems,
        activities,
        worklogs,
      });

      return calcXiaobaoVersionRisk({
        version,
        devTasks: scope?.devTasks ?? [],
        testCases: scope?.testCases ?? [],
        bugs: scope?.bugs ?? [],
        dailyEvidence,
        recentActivityCount: dailyEvidence.recentActivityCount,
        lastActivityAt: dailyEvidence.lastActivityAt,
        snapshots: snapshots.filter((snapshot) => snapshot.versionId === version.id && snapshot.date < today),
        now: calculationNow,
      });
    }).sort((a, b) => b.riskScore - a.riskScore);
  }, [
    activities,
    visibleVersionScopeMap,
    visibleVersions,
    workItemsByVersion,
    worklogs,
    snapshots,
    today,
    calculationNow,
    v22Summaries,
    v22SummaryState,
  ]);

  return {
    risks,
    snapshots,
    insights: mergedInsights,
    pendingInsightKeys,
    insightRequestAttempts,
    riskDataLoaded,
    saveSnapshot,
    saveInsight,
    beginInsightUpdate,
    finishInsightUpdate,
    today,
  };
}