import { Hono } from 'hono';
import { db } from '../db/index';
import { projects, gitCommits, gitPRs, objectives, keyResults, users, projectRepos, krLogs } from '../db/schema';
import { eq, desc, gte, inArray } from 'drizzle-orm';
import { getAllowedProjectIds } from '../services/permissions';
import dayjs from 'dayjs';

/** 根据项目绑定的仓库名，提取纯仓库名 Set */
async function getAllowedRepoNames(allowedProjectIds: string[]): Promise<Set<string>> {
  if (allowedProjectIds.length === 0) return new Set();
  const repos = await db.select().from(projectRepos)
    .where(inArray(projectRepos.projectId, allowedProjectIds));
  return new Set(repos.map(r => {
    let cleaned = r.repoName.trim().replace(/\.git$/, '');
    if (cleaned.includes('://')) {
      try { const parts = new URL(cleaned).pathname.split('/').filter(Boolean); return parts[parts.length - 1] || cleaned; } catch {}
    }
    if (cleaned.includes('/')) return cleaned.split('/').pop() || cleaned;
    return cleaned;
  }));
}

export const overviewRoutes = new Hono();

async function getRecentCommits(allowedRepos?: Set<string>) {
  const recent = await db.select().from(gitCommits).orderBy(desc(gitCommits.committedAt)).limit(50);
  const allUsers = await db.select().from(users);
  const userMap = new Map(allUsers.map(u => [u.id, u.displayName]));
  let filtered = recent;
  if (allowedRepos) {
    filtered = recent.filter(c => allowedRepos.has(c.repoName));
  }
  return filtered.slice(0, 15).map(c => ({
    sha: c.sha?.slice(0, 7) || '',
    message: (c.message || '').split('\n')[0].slice(0, 60),
    authorName: c.userId ? userMap.get(c.userId) || c.authorName : c.authorName,
    repoName: c.repoName,
    committedAt: c.committedAt instanceof Date ? c.committedAt.toISOString() : c.committedAt,
  }));
}

overviewRoutes.get('/overview', async (c) => {
  const user = c.get('user');
  const period = c.req.query('period');
  let projectIds = c.req.query('projectIds')?.split(',').filter(Boolean) || [];

  // 观察者：强制限定到已分配的项目
  const allowedIds = await getAllowedProjectIds(user);
  let mustFilterByProject = false;
  if (allowedIds !== null) {
    mustFilterByProject = true;
    if (projectIds.length > 0) {
      projectIds = projectIds.filter(id => allowedIds.includes(id));
    } else {
      projectIds = allowedIds;
    }
  }

  // 观察者：获取可访问的仓库名（用于过滤 git 相关数据）
  const allowedRepos = mustFilterByProject ? await getAllowedRepoNames(projectIds) : undefined;
  // 观察者：获取可访问项目下的 objective IDs（用于过滤 KR 数据）
  let allowedObjIds: Set<string> | undefined;
  if (mustFilterByProject) {
    const objs = projectIds.length > 0
      ? (await db.select().from(objectives)).filter(o => o.projectId && projectIds.includes(o.projectId))
      : [];
    allowedObjIds = new Set(objs.map(o => o.id));
  }

  // ─── 性能优化:一次性批量拉取,内存里做 join,避免 N+1 ───
  const [allProjects, allObjectivesRaw, allKRs, allUsersData] = await Promise.all([
    db.select().from(projects),
    db.select().from(objectives),
    db.select().from(keyResults),
    db.select().from(users),
  ]);

  // 索引化方便 O(1) 查找
  const objectivesByProject = new Map<string, typeof allObjectivesRaw>();
  for (const o of allObjectivesRaw) {
    if (!o.projectId) continue;
    if (!objectivesByProject.has(o.projectId)) objectivesByProject.set(o.projectId, []);
    objectivesByProject.get(o.projectId)!.push(o);
  }
  const krsByObjective = new Map<string, typeof allKRs>();
  for (const kr of allKRs) {
    if (!krsByObjective.has(kr.objectiveId)) krsByObjective.set(kr.objectiveId, []);
    krsByObjective.get(kr.objectiveId)!.push(kr);
  }
  const usersById = new Map(allUsersData.map(u => [u.id, u]));
  const projectsById = new Map(allProjects.map(p => [p.id, p]));
  const objectivesById = new Map(allObjectivesRaw.map(o => [o.id, o]));

  // 1. 各项目 OKR 整体进度
  const projectOKRProgress: { projectId: string; name: string; identifier: string; progress: number; objectiveCount: number }[] = [];
  for (const proj of allProjects) {
    if ((mustFilterByProject || projectIds.length > 0) && !projectIds.includes(proj.id)) continue;
    let projObjectives = objectivesByProject.get(proj.id) || [];
    if (period) {
      projObjectives = projObjectives.filter(o => o.period === period);
    }
    const avgProgress = projObjectives.length > 0
      ? Math.round(projObjectives.reduce((s, o) => s + (o.progress || 0), 0) / projObjectives.length)
      : 0;
    projectOKRProgress.push({
      projectId: proj.id,
      name: proj.name,
      identifier: proj.identifier || '',
      progress: avgProgress,
      objectiveCount: projObjectives.length,
    });
  }

  // 2. KR 完成状态分布
  let filteredKRs = allKRs;
  if (mustFilterByProject || projectIds.length > 0) {
    const projObjIds = new Set(
      allObjectivesRaw.filter(o => o.projectId && projectIds.includes(o.projectId)).map(o => o.id)
    );
    filteredKRs = allKRs.filter(kr => projObjIds.has(kr.objectiveId));
  }

  const krDistribution = {
    completed: filteredKRs.filter(kr => (kr.currentValue || 0) >= (kr.targetValue || 100)).length,
    inProgress: filteredKRs.filter(kr => {
      const cv = kr.currentValue || 0;
      const tv = kr.targetValue || 100;
      return cv > 0 && cv < tv;
    }).length,
    notStarted: filteredKRs.filter(kr => (kr.currentValue || 0) === 0).length,
    total: filteredKRs.length,
  };

  // 3. 产品线进度（读 OKR 进度）
  const projectProgress = projectOKRProgress.map(p => ({
    projectId: p.projectId,
    name: p.name,
    identifier: p.identifier,
    currentCycleProgress: p.progress,
    totalPoints: p.objectiveCount,
    completedPoints: 0,
  }));

  // 4. Weekly Code Activity (last 12 weeks)
  const twelveWeeksAgo = dayjs().subtract(12, 'week').startOf('week').toDate();
  const [commitsRaw, prsRaw] = await Promise.all([
    db.select().from(gitCommits).where(gte(gitCommits.committedAt, twelveWeeksAgo)),
    db.select().from(gitPRs).where(gte(gitPRs.createdAt, twelveWeeksAgo)),
  ]);
  let commits = commitsRaw;
  let prs = prsRaw;
  if (allowedRepos) {
    commits = commits.filter(c => allowedRepos.has(c.repoName));
    prs = prs.filter(p => allowedRepos.has(p.repoName));
  }
  const allUsers = allUsersData;  // 复用上面已 fetch 的

  const weekMap: Record<string, Record<string, { commits: number; prs: number }>> = {};
  for (let i = 0; i < 12; i++) {
    const ws = dayjs().subtract(11 - i, 'week').startOf('week').format('YYYY-MM-DD');
    weekMap[ws] = {};
  }

  for (const commit of commits) {
    const ws = dayjs(commit.committedAt).startOf('week').format('YYYY-MM-DD');
    if (weekMap[ws] && commit.userId) {
      if (!weekMap[ws][commit.userId]) weekMap[ws][commit.userId] = { commits: 0, prs: 0 };
      weekMap[ws][commit.userId].commits++;
    }
  }

  for (const pr of prs) {
    const ws = dayjs(pr.createdAt).startOf('week').format('YYYY-MM-DD');
    if (weekMap[ws] && pr.userId) {
      if (!weekMap[ws][pr.userId]) weekMap[ws][pr.userId] = { commits: 0, prs: 0 };
      weekMap[ws][pr.userId].prs++;
    }
  }

  const userMap = new Map(allUsers.map(u => [u.id, u.displayName]));
  const weeklyCodeActivity = {
    weeks: Object.entries(weekMap).map(([weekStart, members]) => ({
      weekStart,
      members: Object.entries(members).map(([userId, data]) => ({
        userId,
        name: userMap.get(userId) || 'Unknown',
        ...data,
      })),
    })),
  };

  // 5. OKR Progress(用前面已 fetch 的 allObjectivesRaw + krsByObjective + usersById)
  let allObjectives = period
    ? allObjectivesRaw.filter(o => o.period === period)
    : allObjectivesRaw;

  if (mustFilterByProject || projectIds.length > 0) {
    allObjectives = allObjectives.filter(o => o.projectId && projectIds.includes(o.projectId));
  }

  const okrProgress = allObjectives.map(obj => {
    const krs = krsByObjective.get(obj.id) || [];
    const owner = obj.ownerId ? usersById.get(obj.ownerId) : null;
    return {
      id: obj.id,
      title: obj.title,
      ownerName: owner?.displayName || '未指定',
      progress: obj.progress || 0,
      startDate: obj.startDate || null,
      endDate: obj.endDate || null,
      keyResults: krs.map(kr => ({
        title: kr.title,
        current: kr.currentValue || 0,
        target: kr.targetValue,
        unit: kr.unit || '',
      })),
    };
  });

  // 6. 指定周的 KR（支持 weekOffset 参数，0=本周，1=下周，-1=上周）
  const weekOffset = parseInt(c.req.query('weekOffset') || '0');
  const weekStart = dayjs().startOf('week').add(weekOffset, 'week');
  const weekEnd = dayjs().endOf('week').add(weekOffset, 'week');

  let allKRsRaw = allKRs;  // 复用前面 fetch
  const allObjsMap = objectivesById;
  if (allowedObjIds) {
    allKRsRaw = allKRsRaw.filter(kr => allowedObjIds!.has(kr.objectiveId));
  }

  const thisWeekKRs = allKRsRaw.filter(kr => {
    if (!kr.endDate) return false;
    const end = dayjs(kr.endDate);
    // 严格筛选：截止日期在本周一到本周日之间
    return (end.isAfter(weekStart) || end.isSame(weekStart, 'day')) &&
           (end.isBefore(weekEnd) || end.isSame(weekEnd, 'day'));
  }).sort((a, b) => {
    // 未完成的排前面，已完成的排后面；同状态按截止日期排
    const aDone = (a.currentValue || 0) >= (a.targetValue || 100) ? 1 : 0;
    const bDone = (b.currentValue || 0) >= (b.targetValue || 100) ? 1 : 0;
    if (aDone !== bDone) return aDone - bDone;
    return dayjs(a.endDate).valueOf() - dayjs(b.endDate).valueOf();
  });

  const urgentKRs = [];
  for (const kr of thisWeekKRs.slice(0, 20)) {
    const obj = allObjsMap.get(kr.objectiveId);
    const owner = obj?.ownerId ? usersById.get(obj.ownerId) : null;
    const proj = obj?.projectId ? projectsById.get(obj.projectId) : null;

    const endDate = kr.endDate || '';
    const isOverdue = dayjs(endDate).isBefore(dayjs().startOf('day'));
    const daysLeft = dayjs(endDate).startOf('day').diff(dayjs().startOf('day'), 'day');

    const isCompleted = (kr.currentValue || 0) >= (kr.targetValue || 100);
    const krStatus = kr.status || 'active';

    // 确定显示状态
    let displayStatus: string;
    if (krStatus === 'cancelled') displayStatus = 'cancelled';
    else if (krStatus === 'paused') displayStatus = 'paused';
    else if (isCompleted) displayStatus = 'completed';
    else if (isOverdue) displayStatus = 'overdue';
    else displayStatus = 'active';

    urgentKRs.push({
      id: kr.id,
      title: kr.title,
      progress: kr.currentValue || 0,
      endDate,
      isOverdue: displayStatus === 'overdue',
      isCompleted: displayStatus === 'completed',
      isPaused: displayStatus === 'paused',
      isCancelled: displayStatus === 'cancelled',
      displayStatus,
      daysLeft,
      objectiveTitle: obj?.title || '',
      ownerName: owner?.displayName || '未指定',
      projectName: proj?.name || '',
      projectIdentifier: proj?.identifier || '',
    });
  }

  // 7. 异常事项（逾期未完成 + 暂停 + 取消）
  const abnormalKRs = allKRsRaw.filter(kr => {
    // 暂停的
    if (kr.status === 'paused') return true;
    // 取消的
    if (kr.status === 'cancelled') return true;
    // 逾期未完成的（active 但截止日期已过且未 100%）
    if (kr.status === 'active' && kr.endDate && (kr.currentValue || 0) < (kr.targetValue || 100)) {
      return dayjs(kr.endDate).isBefore(dayjs().startOf('day'));
    }
    return false;
  }).sort((a, b) => {
    // 逾期排最前，暂停其次，取消最后
    const order = (kr: any) => kr.status === 'active' ? 0 : kr.status === 'paused' ? 1 : 2;
    return order(a) - order(b);
  });

  // 批量取异常 KRs 的最后日志(单次 IN 查询代替循环)
  const abnormalKrIds = abnormalKRs.slice(0, 20).map(k => k.id);
  const lastLogByKr = new Map<string, string>();
  if (abnormalKrIds.length > 0) {
    const logs = await db.select().from(krLogs)
      .where(inArray(krLogs.krId, abnormalKrIds))
      .orderBy(desc(krLogs.createdAt));
    for (const log of logs) {
      if (!lastLogByKr.has(log.krId)) lastLogByKr.set(log.krId, log.detail || '');
    }
  }

  const overdueList = [];
  for (const kr of abnormalKRs.slice(0, 20)) {
    const obj = allObjsMap.get(kr.objectiveId);
    const owner = obj?.ownerId ? usersById.get(obj.ownerId) : null;
    const proj = obj?.projectId ? projectsById.get(obj.projectId) : null;
    const reason = lastLogByKr.get(kr.id) || '';

    let itemStatus: string;
    let statusLabel: string;
    if (kr.status === 'paused') {
      itemStatus = 'paused';
      statusLabel = '已暂停';
    } else if (kr.status === 'cancelled') {
      itemStatus = 'cancelled';
      statusLabel = '已取消';
    } else {
      itemStatus = 'overdue';
      statusLabel = '逾期' + dayjs().startOf('day').diff(dayjs(kr.endDate!).startOf('day'), 'day') + '天';
    }

    overdueList.push({
      id: kr.id,
      title: kr.title,
      progress: kr.currentValue || 0,
      endDate: kr.endDate,
      status: itemStatus,
      statusLabel,
      reason,
      ownerName: owner?.displayName || '未指定',
      projectName: proj?.name || '',
      projectIdentifier: proj?.identifier || '',
    });
  }

  const activeKRs = urgentKRs.filter(kr => !kr.isCancelled && !kr.isPaused);
  const weeklyTotal = urgentKRs.length;
  const weeklyCompleted = urgentKRs.filter(kr => kr.isCompleted).length;
  const weeklyCancelled = urgentKRs.filter(kr => kr.isCancelled).length;
  const weeklyPaused = urgentKRs.filter(kr => kr.isPaused).length;
  const weeklyAvgProgress = activeKRs.length > 0
    ? Math.round(activeKRs.reduce((s, kr) => s + kr.progress, 0) / activeKRs.length)
    : 0;

  return c.json({
    code: 0,
    data: {
      projectOKRProgress,
      krDistribution,
      projectProgress,
      weeklyCodeActivity,
      okrProgress,
      urgentKRs,
      weeklyKRStats: {
        total: weeklyTotal, completed: weeklyCompleted, avgProgress: weeklyAvgProgress,
        weekOffset,
        weekLabel: weekStart.format('MM/DD') + ' ~ ' + weekEnd.format('MM/DD'),
      },
      overdueKRs: overdueList,
      recentCommits: await getRecentCommits(allowedRepos),
    },
    message: 'success',
  });
});