import { attendance_leave_type } from '@prisma/client';
import prisma from '../config/database';

const VALID_LEAVE_TYPES = ['work', 'vacation', 'sick', 'holiday', 'unpaid'] as const;

const MONTH_NAMES = [
  'Leden', 'Únor', 'Březen', 'Duben', 'Květen', 'Červen',
  'Červenec', 'Srpen', 'Září', 'Říjen', 'Listopad', 'Prosinec',
];

// ── Helpers ──────────────────────────────────────────────────────────

function countWorkingDays(year: number, month: number, upToDay?: number): number {
  let count = 0;
  const cur = new Date(year, month, 1);
  while (cur.getMonth() === month && (!upToDay || cur.getDate() <= upToDay)) {
    const dow = cur.getDay();
    if (dow !== 0 && dow !== 6) count++;
    cur.setDate(cur.getDate() + 1);
  }
  return count;
}

function calcWorkedHours(arrival: Date, departure: Date, breakStart: Date | null, breakEnd: Date | null): number {
  let mins = (departure.getTime() - arrival.getTime()) / 60000;
  if (breakStart && breakEnd) {
    mins -= (breakEnd.getTime() - breakStart.getTime()) / 60000;
  }
  return Math.max(0, mins) / 60;
}

const roundUp15 = (d: Date) => {
  const ms = 15 * 60 * 1000;
  return new Date(Math.ceil(d.getTime() / ms) * ms);
};

const roundDown15 = (d: Date) => {
  const ms = 15 * 60 * 1000;
  return new Date(Math.floor(d.getTime() / ms) * ms);
};

// ── Interfaces ───────────────────────────────────────────────────────

export interface ListAttendanceParams {
  page: number;
  limit: number;
  skip: number;
  order: 'asc' | 'desc';
  userId?: number;
  isAdmin: boolean;
  authUserId: number;
  month?: number;
  year?: number;
}

export interface PunchData {
  punch_action: string;
  latitude?: number | string | null;
  longitude?: number | string | null;
  accuracy?: number | string | null;
  address?: string | null;
}

export interface CreateAttendanceData {
  user_id?: number;
  shift_date: string;
  arrival_time?: string | null;
  arrival_lat?: number | null;
  arrival_lng?: number | null;
  arrival_accuracy?: number | null;
  arrival_address?: string | null;
  departure_time?: string | null;
  departure_lat?: number | null;
  departure_lng?: number | null;
  departure_accuracy?: number | null;
  departure_address?: string | null;
  notes?: string | null;
  project_id?: number | null;
  leave_type: string;
  leave_hours?: number | null;
  project_logs?: Array<{ project_id: number; hours?: number; minutes?: number }>;
}

export interface UpdateAttendanceData {
  arrival_time?: string | null;
  departure_time?: string | null;
  break_start?: string | null;
  break_end?: string | null;
  notes?: string | null;
  project_id?: number | null;
  leave_type?: string;
  leave_hours?: number | null;
  project_logs?: Array<{ project_id: number; hours?: number; minutes?: number }>;
}

export interface LeaveData {
  user_id?: number;
  date_from: string;
  date_to?: string;
  leave_type: string;
  leave_hours?: number;
  notes?: string;
}

export interface BulkAttendanceData {
  month: string;
  user_ids: number[];
  arrival_time: string;
  departure_time: string;
  break_start_time: string;
  break_end_time: string;
}

export interface BalancesData {
  user_id: number;
  year?: number;
  action_type: string;
  vacation_total?: number | null;
  vacation_used?: number | null;
  sick_used?: number | null;
}

// ── Service Functions ────────────────────────────────────────────────

export async function getStatus(userId: number) {
  const now = new Date();
  const y = now.getFullYear(), m = now.getMonth(), d = now.getDate();
  const todayStart = new Date(y, m, d, 0, 0, 0);
  const todayEnd = new Date(y, m, d, 23, 59, 59);

  // 1) Ongoing shift (no departure)
  const ongoingShift = await prisma.attendance.findFirst({
    where: { user_id: userId, departure_time: null, arrival_time: { not: null } },
    orderBy: { created_at: 'desc' },
  });

  // 2) Today's completed shifts
  const todayShifts = await prisma.attendance.findMany({
    where: {
      user_id: userId,
      shift_date: { gte: todayStart, lte: todayEnd },
      departure_time: { not: null },
    },
    orderBy: { arrival_time: 'asc' },
  });

  // 3) Leave balance
  const balance = await prisma.leave_balances.findFirst({
    where: { user_id: userId, year: y },
  });
  const leaveBalance = {
    vacation_total: balance ? Number(balance.vacation_total) : 160,
    vacation_used: balance ? Number(balance.vacation_used) : 0,
    vacation_remaining: balance ? Number(balance.vacation_total) - Number(balance.vacation_used) : 160,
    sick_used: balance ? Number(balance.sick_used) : 0,
  };

  // 4) Monthly fund
  const monthStart = new Date(y, m, 1);
  const monthEnd = new Date(y, m + 1, 0, 23, 59, 59);
  const monthRecords = await prisma.attendance.findMany({
    where: { user_id: userId, shift_date: { gte: monthStart, lte: monthEnd } },
  });

  const workingDays = countWorkingDays(y, m);
  const fund = workingDays * 8;

  let workedHours = 0;
  let vacationHours = 0;
  let sickHours = 0;
  let holidayHours = 0;
  let unpaidHours = 0;

  for (const rec of monthRecords) {
    const lt = (rec.leave_type as string) || 'work';
    if (lt !== 'work') {
      const hrs = Number(rec.leave_hours) || 8;
      if (lt === 'vacation') vacationHours += hrs;
      else if (lt === 'sick') sickHours += hrs;
      else if (lt === 'holiday') holidayHours += hrs;
      else if (lt === 'unpaid') unpaidHours += hrs;
      continue;
    }
    if (rec.arrival_time && rec.departure_time) {
      workedHours += calcWorkedHours(rec.arrival_time, rec.departure_time, rec.break_start, rec.break_end);
    }
  }

  const worked = Math.round(workedHours * 100) / 100;
  const holidayDays = monthRecords.filter(r => (r.leave_type as string) === 'holiday').length;
  const adjustedFund = Math.max(0, (workingDays - holidayDays) * 8);
  const leaveHours = vacationHours + sickHours;
  const covered = worked + leaveHours;
  const remaining = Math.max(0, adjustedFund - covered);
  const overtime = Math.max(0, covered - adjustedFund);

  const monthlyFund = {
    month_name: `${MONTH_NAMES[m]} ${y}`,
    fund: adjustedFund,
    business_days: workingDays - holidayDays,
    worked,
    covered,
    remaining,
    overtime,
    leave_hours: leaveHours,
    vacation_hours: vacationHours,
    sick_hours: sickHours,
    holiday_hours: holidayHours,
    unpaid_hours: unpaidHours,
  };

  // 5) Project logs for ongoing shift
  let projectLogs: Array<{ id: number; attendance_id: number; project_id: number; started_at: Date | null; ended_at: Date | null; project_name?: string }> = [];
  let activeProjectId: number | null = null;

  if (ongoingShift) {
    const logs = await prisma.attendance_project_logs.findMany({
      where: { attendance_id: ongoingShift.id },
      orderBy: { started_at: 'asc' },
    });

    const projectIds = [...new Set(logs.map(l => l.project_id))];
    const projectNames = new Map<number, string>();
    if (projectIds.length > 0) {
      const projects = await prisma.projects.findMany({
        where: { id: { in: projectIds } },
        select: { id: true, name: true, project_number: true },
      });
      for (const p of projects) {
        projectNames.set(p.id, p.project_number ? `${p.project_number} – ${p.name}` : (p.name || ''));
      }
    }

    projectLogs = logs.map(l => ({
      ...l,
      project_name: projectNames.get(l.project_id) || `Projekt #${l.project_id}`,
    }));

    const activeLog = logs.find(l => l.ended_at === null);
    if (activeLog) {
      activeProjectId = activeLog.project_id;
    } else {
      activeProjectId = ongoingShift.project_id ?? null;
    }
  }

  return {
    ongoing_shift: ongoingShift,
    today_shifts: todayShifts,
    leave_balance: leaveBalance,
    monthly_fund: monthlyFund,
    date: now.toISOString().split('T')[0],
    project_logs: projectLogs,
    active_project_id: activeProjectId,
  };
}

export async function saveNotes(userId: number, notes: string | null) {
  const ongoing = await prisma.attendance.findFirst({
    where: { user_id: userId, departure_time: null, arrival_time: { not: null } },
    orderBy: { created_at: 'desc' },
  });
  if (!ongoing) return { error: 'Nemáte aktivní směnu.' };

  await prisma.attendance.update({
    where: { id: ongoing.id },
    data: { notes: notes ? String(notes) : null },
  });

  return { success: true };
}

export async function updateAddress(userId: number, address: string | null, punchAction: string) {
  const latest = await prisma.attendance.findFirst({
    where: { user_id: userId },
    orderBy: { created_at: 'desc' },
  });
  if (!latest) return { error: 'Nenalezen záznam' };

  const data: Record<string, unknown> = {};
  if (punchAction === 'departure') {
    data.departure_address = address;
  } else {
    data.arrival_address = address;
  }

  await prisma.attendance.update({ where: { id: latest.id }, data });
  return { success: true };
}

export async function switchProject(userId: number, projectId: number | null) {
  const ongoing = await prisma.attendance.findFirst({
    where: { user_id: userId, departure_time: null, arrival_time: { not: null } },
    orderBy: { created_at: 'desc' },
  });
  if (!ongoing) return { error: 'Nemáte aktivní směnu.' };

  const now = new Date();

  await prisma.attendance_project_logs.updateMany({
    where: { attendance_id: ongoing.id, ended_at: null },
    data: { ended_at: now },
  });

  if (projectId) {
    await prisma.attendance_project_logs.create({
      data: {
        attendance_id: ongoing.id,
        project_id: projectId,
        started_at: now,
        ended_at: null,
      },
    });
  }

  await prisma.attendance.update({
    where: { id: ongoing.id },
    data: { project_id: projectId },
  });

  return { success: true };
}

export async function getBalances(year: number) {
  const users = await prisma.users.findMany({
    where: { is_active: true },
    select: { id: true, first_name: true, last_name: true },
    orderBy: { last_name: 'asc' },
  });

  const balances: Record<string, { name: string; vacation_total: number; vacation_used: number; vacation_remaining: number; sick_used: number }> = {};
  for (const u of users) {
    const lb = await prisma.leave_balances.findFirst({ where: { user_id: u.id, year } });
    const vTotal = lb ? Number(lb.vacation_total) : 160;
    const vUsed = lb ? Number(lb.vacation_used) : 0;
    const sUsed = lb ? Number(lb.sick_used) : 0;
    balances[String(u.id)] = {
      name: `${u.first_name} ${u.last_name}`.trim(),
      vacation_total: vTotal,
      vacation_used: vUsed,
      vacation_remaining: vTotal - vUsed,
      sick_used: sUsed,
    };
  }

  return {
    users: users.map(u => ({ id: u.id, name: `${u.first_name} ${u.last_name}`.trim() })),
    balances,
  };
}

export async function getWorkfund(year: number) {
  const users = await prisma.users.findMany({
    where: { is_active: true },
    select: { id: true, first_name: true, last_name: true },
    orderBy: { last_name: 'asc' },
  });

  const now = new Date();
  const currentYear = now.getFullYear();
  const currentMonth = now.getMonth(); // 0-based
  const maxMonth = year < currentYear ? 11 : (year === currentYear ? currentMonth : -1);

  if (maxMonth < 0) {
    return { months: {}, users: users.map(u => ({ id: u.id, name: `${u.first_name} ${u.last_name}`.trim() })), balances: {} };
  }

  const yearStart = new Date(year, 0, 1);
  const yearEnd = new Date(year, maxMonth + 1, 0, 23, 59, 59);
  const allRecords = await prisma.attendance.findMany({
    where: { shift_date: { gte: yearStart, lte: yearEnd } },
  });

  const months: Record<string, { month_name: string; fund: number; fund_to_date: number; business_days: number; users: Record<string, { name: string; worked: number; covered: number; overtime: number; missing: number }> }> = {};

  for (let m = 0; m <= maxMonth; m++) {
    const isCurrentMonth = year === currentYear && m === currentMonth;
    const bizDays = countWorkingDays(year, m);
    const bizDaysToDate = isCurrentMonth ? countWorkingDays(year, m, now.getDate()) : bizDays;
    const fund = bizDays * 8;
    const fundToDate = bizDaysToDate * 8;
    const monthStart = new Date(year, m, 1);
    const monthEnd = new Date(year, m + 1, 0, 23, 59, 59);

    const monthUsers: Record<string, { name: string; worked: number; covered: number; overtime: number; missing: number }> = {};

    for (const u of users) {
      const recs = allRecords.filter(r => r.user_id === u.id && r.shift_date >= monthStart && r.shift_date <= monthEnd);
      let worked = 0;
      let vacationHours = 0;
      let sickHours = 0;
      let holidayDays = 0;

      for (const rec of recs) {
        const lt = (rec.leave_type as string) || 'work';
        if (lt === 'work') {
          if (rec.arrival_time && rec.departure_time) {
            worked += calcWorkedHours(rec.arrival_time, rec.departure_time, rec.break_start, rec.break_end);
          }
        } else if (lt === 'vacation') {
          vacationHours += Number(rec.leave_hours) || 8;
        } else if (lt === 'sick') {
          sickHours += Number(rec.leave_hours) || 8;
        } else if (lt === 'holiday') {
          holidayDays++;
        }
      }

      const userFund = bizDaysToDate * 8;
      const workedRound = Math.round(worked * 10) / 10;
      const holidayHours = holidayDays * 8;
      const leaveHours = vacationHours + sickHours + holidayHours;
      const covered = Math.round((worked + leaveHours) * 10) / 10;
      const missing = Math.max(0, Math.round((userFund - covered) * 10) / 10);
      const overtime = Math.max(0, Math.round((covered - userFund) * 10) / 10);

      monthUsers[String(u.id)] = {
        name: `${u.first_name} ${u.last_name}`.trim(),
        worked: workedRound,
        covered,
        overtime,
        missing,
      };
    }

    months[String(m + 1)] = {
      month_name: MONTH_NAMES[m],
      fund,
      fund_to_date: fundToDate,
      business_days: bizDays,
      users: monthUsers,
    };
  }

  return {
    months,
    users: users.map(u => ({ id: u.id, name: `${u.first_name} ${u.last_name}`.trim() })),
    balances: {},
    holidays: [],
  };
}

export async function getProjectReport(year: number) {
  const yearStart = new Date(year, 0, 1);
  const yearEnd = new Date(year, 11, 31, 23, 59, 59);

  const records = await prisma.attendance.findMany({
    where: {
      shift_date: { gte: yearStart, lte: yearEnd },
      leave_type: 'work',
      arrival_time: { not: null },
      departure_time: { not: null },
    },
    include: {
      users: { select: { id: true, first_name: true, last_name: true } },
    },
  });

  const projectIds = [...new Set(records.filter(r => r.project_id).map(r => r.project_id!))];
  const projectsMap = new Map<number, { name: string; project_number: string }>();
  if (projectIds.length > 0) {
    const projects = await prisma.projects.findMany({
      where: { id: { in: projectIds } },
      select: { id: true, name: true, project_number: true },
    });
    for (const p of projects) {
      projectsMap.set(p.id, { name: p.name || '', project_number: p.project_number || '' });
    }
  }

  const months: Record<string, { month_name: string; projects: Array<{ project_id: number | null; project_number?: string; project_name?: string; hours: number; users: Array<{ user_id: number; user_name: string; hours: number }> }> }> = {};

  for (let m = 0; m < 12; m++) {
    const monthStart = new Date(year, m, 1);
    const monthEnd = new Date(year, m + 1, 0, 23, 59, 59);
    const monthRecs = records.filter(r => r.shift_date >= monthStart && r.shift_date <= monthEnd);

    if (monthRecs.length === 0) continue;

    const projectMap = new Map<number | null, { project_number?: string; project_name?: string; userMap: Map<number, { name: string; hours: number }> }>();

    for (const rec of monthRecs) {
      const hours = calcWorkedHours(rec.arrival_time!, rec.departure_time!, rec.break_start, rec.break_end);
      const pid = rec.project_id;

      if (!projectMap.has(pid)) {
        const projInfo = pid ? projectsMap.get(pid) : undefined;
        projectMap.set(pid, {
          project_number: projInfo?.project_number || undefined,
          project_name: projInfo?.name || undefined,
          userMap: new Map(),
        });
      }

      const pg = projectMap.get(pid)!;
      const uid = rec.user_id;
      const uName = rec.users ? `${rec.users.first_name} ${rec.users.last_name}`.trim() : `User #${uid}`;
      if (!pg.userMap.has(uid)) {
        pg.userMap.set(uid, { name: uName, hours: 0 });
      }
      pg.userMap.get(uid)!.hours += hours;
    }

    const projects = Array.from(projectMap.entries()).map(([pid, pg]) => ({
      project_id: pid,
      project_number: pg.project_number,
      project_name: pg.project_name,
      hours: Math.round(Array.from(pg.userMap.values()).reduce((s, u) => s + u.hours, 0) * 10) / 10,
      users: Array.from(pg.userMap.entries()).map(([uid, ud]) => ({
        user_id: uid,
        user_name: ud.name,
        hours: Math.round(ud.hours * 10) / 10,
      })),
    }));

    months[String(m + 1)] = {
      month_name: MONTH_NAMES[m],
      projects,
    };
  }

  return { months };
}

export async function getPrintData(monthStr: string, filterUserId: number | null) {
  const [yearStr, monthNumStr] = monthStr.split('-');
  const yr = Number(yearStr);
  const mo = Number(monthNumStr);

  const monthStart = new Date(yr, mo - 1, 1);
  const monthEnd = new Date(yr, mo, 0, 23, 59, 59);

  const users = await prisma.users.findMany({
    where: { is_active: true },
    select: { id: true, first_name: true, last_name: true },
    orderBy: { last_name: 'asc' },
  });

  const where: Record<string, unknown> = {
    shift_date: { gte: monthStart, lte: monthEnd },
  };
  if (filterUserId) where.user_id = filterUserId;

  const records = await prisma.attendance.findMany({
    where,
    include: {
      users: { select: { id: true, first_name: true, last_name: true } },
      attendance_project_logs: {
        orderBy: { started_at: 'asc' },
      },
    },
    orderBy: [{ users: { last_name: 'asc' } }, { shift_date: 'asc' }],
  });

  const fundHours = countWorkingDays(yr, mo - 1) * 8;

  // Load project names for enrichment
  const projectIds = [...new Set(records.flatMap(r => (r as any).attendance_project_logs?.map((l: any) => l.project_id) || []).filter(Boolean))];
  const projectMap: Record<number, string> = {};
  if (projectIds.length > 0) {
    const projects = await prisma.projects.findMany({
      where: { id: { in: projectIds } },
      select: { id: true, name: true, project_number: true },
    });
    for (const p of projects) {
      projectMap[p.id] = p.project_number ? `${p.project_number} – ${p.name}` : (p.name || `#${p.id}`);
    }
  }

  // Group records by user and calculate totals
  const userTotals: Record<string, Record<string, unknown>> = {};
  for (const rec of records) {
    const uid = String(rec.user_id);
    if (!userTotals[uid]) {
      const u = (rec as any).users;
      userTotals[uid] = {
        name: u ? `${u.first_name} ${u.last_name}`.trim() : `User #${uid}`,
        minutes: 0,
        records: [],
        vacation_hours: 0,
        sick_hours: 0,
        holiday_hours: 0,
        unpaid_hours: 0,
        fund: fundHours,
        worked_hours: 0,
        covered: 0,
        missing: 0,
        overtime: 0,
      };
    }

    // Build record with project_logs for frontend
    const projectLogs = (rec as any).attendance_project_logs?.map((log: any) => ({
      project_id: log.project_id,
      project_name: projectMap[log.project_id] || null,
      hours: log.hours,
      minutes: log.minutes,
      started_at: log.started_at,
      ended_at: log.ended_at,
    })) || [];

    (userTotals[uid].records as unknown[]).push({
      ...rec,
      project_logs: projectLogs,
      project_name: projectLogs.length > 0 ? projectLogs[0].project_name : null,
    });

    const lt = (rec.leave_type as string) || 'work';
    if (lt !== 'work') {
      const hrs = Number(rec.leave_hours) || 8;
      if (lt === 'vacation') (userTotals[uid].vacation_hours as number) += hrs;
      else if (lt === 'sick') (userTotals[uid].sick_hours as number) += hrs;
      else if (lt === 'holiday') (userTotals[uid].holiday_hours as number) += hrs;
      else if (lt === 'unpaid') (userTotals[uid].unpaid_hours as number) += hrs;
    } else if (rec.arrival_time && rec.departure_time) {
      const mins = calcWorkedHours(rec.arrival_time, rec.departure_time, rec.break_start, rec.break_end) * 60;
      (userTotals[uid].minutes as number) += Math.round(mins);
    }
  }

  // Calculate fund coverage per user
  for (const uid of Object.keys(userTotals)) {
    const ut = userTotals[uid];
    const workedH = Math.round((ut.minutes as number) / 60 * 10) / 10;
    ut.worked_hours = workedH;
    const covered = workedH + (ut.vacation_hours as number) + (ut.sick_hours as number) + (ut.holiday_hours as number);
    ut.covered = Math.round(covered * 10) / 10;
    ut.missing = Math.max(0, Math.round(((ut.fund as number) - covered) * 10) / 10);
    ut.overtime = Math.max(0, Math.round((covered - (ut.fund as number)) * 10) / 10);
  }

  // Leave balances
  const leaveBalances: Record<string, Record<string, number>> = {};
  const balanceRecords = await prisma.leave_balances.findMany({ where: { year: yr } });
  for (const bal of balanceRecords) {
    const uid = String(bal.user_id);
    leaveBalances[uid] = {
      vacation_total: Number(bal.vacation_total) || 160,
      vacation_remaining: (Number(bal.vacation_total) || 160) - (Number(bal.vacation_used) || 0),
    };
  }

  // Selected user name
  let selectedUserName = '';
  if (filterUserId) {
    const u = users.find(u => u.id === filterUserId);
    if (u) selectedUserName = `${u.first_name} ${u.last_name}`.trim();
  }

  return {
    user_totals: userTotals,
    leave_balances: leaveBalances,
    users: users.map(u => ({ id: u.id, name: `${u.first_name} ${u.last_name}`.trim() })),
    month: monthStr,
    month_name: `${MONTH_NAMES[mo - 1]} ${yr}`,
    selected_user: filterUserId,
    selected_user_name: selectedUserName,
    year: yr,
    fund: { business_days: countWorkingDays(yr, mo - 1), hours: fundHours },
  };
}

export async function getActiveProjects() {
  const activeProjects = await prisma.projects.findMany({
    where: { status: 'aktivni' },
    select: { id: true, name: true, project_number: true },
    orderBy: { name: 'asc' },
  });
  return activeProjects.map(p => ({
    id: p.id,
    name: p.project_number ? `${p.project_number} – ${p.name}` : p.name,
  }));
}

export async function getProjectLogs(attendanceId: number) {
  return prisma.attendance_project_logs.findMany({
    where: { attendance_id: attendanceId },
    orderBy: { started_at: 'asc' },
  });
}

export async function getLocationRecord(id: number) {
  return prisma.attendance.findUnique({
    where: { id },
    include: { users: { select: { id: true, first_name: true, last_name: true } } },
  });
}

export async function listAttendance(params: ListAttendanceParams) {
  const { page, limit, skip, order, isAdmin, authUserId } = params;

  const where: Record<string, unknown> = {};
  if (!isAdmin) {
    where.user_id = authUserId;
  } else if (params.userId) {
    where.user_id = params.userId;
  }
  if (params.month && params.year) {
    where.shift_date = {
      gte: new Date(params.year, params.month - 1, 1),
      lt: new Date(params.year, params.month, 1),
    };
  }

  const [records, total] = await Promise.all([
    prisma.attendance.findMany({
      where,
      skip,
      take: limit,
      orderBy: { shift_date: order },
      include: {
        users: { select: { id: true, first_name: true, last_name: true, username: true } },
        attendance_project_logs: { orderBy: { started_at: 'asc' } },
      },
    }),
    prisma.attendance.count({ where }),
  ]);

  const allProjectIds = new Set<number>();
  for (const rec of records) {
    if (rec.project_id) allProjectIds.add(rec.project_id);
    for (const log of rec.attendance_project_logs) {
      allProjectIds.add(log.project_id);
    }
  }
  const projectNameMap = new Map<number, string>();
  if (allProjectIds.size > 0) {
    const projects = await prisma.projects.findMany({
      where: { id: { in: [...allProjectIds] } },
      select: { id: true, name: true, project_number: true },
    });
    for (const p of projects) {
      projectNameMap.set(p.id, p.project_number ? `${p.project_number} – ${p.name}` : (p.name || ''));
    }
  }

  const enriched = records.map(rec => {
    const logs = rec.attendance_project_logs.map(l => ({
      ...l,
      project_name: projectNameMap.get(l.project_id) || `Projekt #${l.project_id}`,
    }));
    const u = rec.users;
    return {
      ...rec,
      user_name: u ? `${u.first_name} ${u.last_name}`.trim() : '',
      project_name: rec.project_id ? (projectNameMap.get(rec.project_id) || null) : null,
      project_logs: logs,
    };
  });

  return { records: enriched, total, page, limit };
}

export async function handleBalances(data: BalancesData) {
  const yr = data.year || new Date().getFullYear();

  if (data.action_type === 'edit') {
    await prisma.leave_balances.upsert({
      where: { user_id_year: { user_id: data.user_id, year: yr } },
      update: {
        vacation_total: data.vacation_total != null ? Number(data.vacation_total) : undefined,
        vacation_used: data.vacation_used != null ? Number(data.vacation_used) : undefined,
        sick_used: data.sick_used != null ? Number(data.sick_used) : undefined,
        updated_at: new Date(),
      },
      create: {
        user_id: data.user_id,
        year: yr,
        vacation_total: Number(data.vacation_total) || 160,
        vacation_used: Number(data.vacation_used) || 0,
        sick_used: Number(data.sick_used) || 0,
      },
    });
    return { success: true, message: 'Bilance byla uložena', year: yr };
  }

  if (data.action_type === 'reset') {
    await prisma.leave_balances.upsert({
      where: { user_id_year: { user_id: data.user_id, year: yr } },
      update: { vacation_used: 0, sick_used: 0, updated_at: new Date() },
      create: { user_id: data.user_id, year: yr, vacation_total: 160, vacation_used: 0, sick_used: 0 },
    });
    return { success: true, message: 'Bilance byla resetována', year: yr };
  }

  return { error: 'Neplatný typ akce' };
}

export async function bulkCreateAttendance(data: BulkAttendanceData) {
  const [yrStr, moStr] = data.month.split('-');
  const yr = Number(yrStr);
  const mo = Number(moStr);
  const daysInMonth = new Date(yr, mo, 0).getDate();

  const dateFrom = new Date(yr, mo - 1, 1);
  const dateTo = new Date(yr, mo, 0, 23, 59, 59);
  const existing = await prisma.attendance.findMany({
    where: { user_id: { in: data.user_ids.map(Number) }, shift_date: { gte: dateFrom, lte: dateTo } },
    select: { user_id: true, shift_date: true },
  });
  const existingSet = new Set(existing.map(r => `${r.user_id}:${r.shift_date.toISOString().split('T')[0]}`));

  let inserted = 0;
  let skipped = 0;

  for (const userId of data.user_ids.map(Number)) {
    for (let day = 1; day <= daysInMonth; day++) {
      const date = new Date(yr, mo - 1, day);
      const dateStr = date.toISOString().split('T')[0];
      const dow = date.getDay();

      if (dow === 0 || dow === 6) continue;

      if (existingSet.has(`${userId}:${dateStr}`)) {
        skipped++;
        continue;
      }

      const shiftDate = new Date(Date.UTC(yr, mo - 1, day, 12, 0, 0));
      await prisma.attendance.create({
        data: {
          user_id: userId,
          shift_date: shiftDate,
          arrival_time: new Date(`${dateStr}T${data.arrival_time}:00`),
          departure_time: new Date(`${dateStr}T${data.departure_time}:00`),
          break_start: new Date(`${dateStr}T${data.break_start_time}:00`),
          break_end: new Date(`${dateStr}T${data.break_end_time}:00`),
          leave_type: 'work',
        },
      });
      inserted++;
    }
  }

  let msg = `Vytvořeno ${inserted} záznamů`;
  if (skipped > 0) msg += ` (${skipped} přeskočeno — již existují)`;

  return { inserted, skipped, message: msg };
}

export async function createLeave(data: LeaveData, authUserId: number) {
  const userId = data.user_id ?? authUserId;
  const dateFrom = data.date_from;
  const dateTo = data.date_to || dateFrom;
  const leaveTypeStr = data.leave_type;
  if (!VALID_LEAVE_TYPES.includes(leaveTypeStr as typeof VALID_LEAVE_TYPES[number])) {
    return { error: 'Neplatný typ nepřítomnosti' };
  }
  const leaveType = leaveTypeStr as attendance_leave_type;

  if (!dateFrom) return { error: 'Datum je povinné' };

  const start = new Date(dateFrom);
  const end = new Date(dateTo);
  let created = 0;

  const current = new Date(start);
  while (current <= end) {
    const dow = current.getDay();
    if (dow !== 0 && dow !== 6) {
      const dateStr = current.toISOString().split('T')[0];
      const shiftDate = new Date(Date.UTC(current.getFullYear(), current.getMonth(), current.getDate(), 12, 0, 0));
      await prisma.attendance.create({
        data: {
          user_id: userId,
          shift_date: shiftDate,
          leave_type: leaveType,
          leave_hours: data.leave_hours ? Number(data.leave_hours) : 8,
          notes: data.notes ? String(data.notes) : null,
        },
      });
      created++;
    }
    current.setDate(current.getDate() + 1);
  }

  // Update leave balance for vacation/sick
  const totalLeaveHours = created * (data.leave_hours ? Number(data.leave_hours) : 8);
  if ((leaveType === 'vacation' || leaveType === 'sick') && totalLeaveHours > 0) {
    const year = new Date(dateFrom).getFullYear();
    const existingBalance = await prisma.leave_balances.findFirst({
      where: { user_id: userId, year },
    });
    if (existingBalance) {
      const updateField = leaveType === 'vacation' ? 'vacation_used' : 'sick_used';
      await prisma.leave_balances.update({
        where: { id: existingBalance.id },
        data: { [updateField]: Number(existingBalance[updateField]) + totalLeaveHours, updated_at: new Date() },
      });
    } else {
      await prisma.leave_balances.create({
        data: {
          user_id: userId,
          year,
          vacation_total: 160,
          vacation_used: leaveType === 'vacation' ? totalLeaveHours : 0,
          sick_used: leaveType === 'sick' ? totalLeaveHours : 0,
        },
      });
    }
  }

  return { created, message: `Vytvořeno ${created} záznamů nepřítomnosti` };
}

export async function punchAction(userId: number, data: PunchData) {
  const action = data.punch_action;
  const now = new Date();
  const y = now.getFullYear(), m = now.getMonth(), d = now.getDate();
  const today = new Date(Date.UTC(y, m, d, 12, 0, 0));

  const gpsLat = data.latitude != null && data.latitude !== '' ? Number(data.latitude) : null;
  const gpsLng = data.longitude != null && data.longitude !== '' ? Number(data.longitude) : null;
  const gpsAcc = data.accuracy != null && data.accuracy !== '' ? Number(data.accuracy) : null;
  const gpsAddr = data.address ?? null;

  if (action === 'arrival') {
    const ongoing = await prisma.attendance.findFirst({
      where: { user_id: userId, departure_time: null, arrival_time: { not: null } },
      orderBy: { created_at: 'desc' },
    });
    if (ongoing) {
      return { error: 'Máte již aktivní směnu. Nejdříve zaznamenejte odchod.' };
    }

    const arrivalTime = roundUp15(now);
    const record = await prisma.attendance.create({
      data: {
        user_id: userId,
        shift_date: today,
        arrival_time: arrivalTime,
        arrival_lat: gpsLat,
        arrival_lng: gpsLng,
        arrival_accuracy: gpsAcc,
        arrival_address: gpsAddr,
        leave_type: 'work',
      },
    });

    return { id: record.id, status: 201, message: 'Příchod zaznamenán', auditAction: 'create' as const, auditDescription: 'Zaznamenán příchod' };

  } else if (action === 'departure') {
    const ongoing = await prisma.attendance.findFirst({
      where: { user_id: userId, departure_time: null, arrival_time: { not: null } },
      orderBy: { created_at: 'desc' },
    });
    if (!ongoing) {
      return { error: 'Nemáte aktivní směnu.' };
    }

    const departureTime = roundDown15(now);

    const updateData: Record<string, unknown> = {
      departure_time: departureTime,
      departure_lat: gpsLat,
      departure_lng: gpsLng,
      departure_accuracy: gpsAcc,
      departure_address: gpsAddr,
    };

    if (!ongoing.break_start && ongoing.arrival_time) {
      const shiftMs = departureTime.getTime() - ongoing.arrival_time.getTime();
      const shiftHours = shiftMs / (1000 * 60 * 60);
      if (shiftHours > 6) {
        const midpoint = new Date(ongoing.arrival_time.getTime() + shiftMs / 2);
        const breakMins = shiftHours > 12 ? 30 : 15;
        updateData.break_start = midpoint;
        updateData.break_end = new Date(midpoint.getTime() + breakMins * 60 * 1000);
      }
    }

    await prisma.attendance.update({ where: { id: ongoing.id }, data: updateData });

    await prisma.attendance_project_logs.updateMany({
      where: { attendance_id: ongoing.id, ended_at: null },
      data: { ended_at: departureTime },
    });

    return { id: ongoing.id, status: 200, message: 'Odchod zaznamenán', auditAction: 'update' as const, auditDescription: 'Zaznamenán odchod' };

  } else if (action === 'break_start') {
    const ongoing = await prisma.attendance.findFirst({
      where: { user_id: userId, departure_time: null, arrival_time: { not: null }, break_start: null },
      orderBy: { created_at: 'desc' },
    });
    if (!ongoing) {
      return { error: 'Nemáte aktivní směnu bez přestávky.' };
    }

    const ms10 = 10 * 60 * 1000;
    const breakStart = new Date(Math.round(now.getTime() / ms10) * ms10);
    const breakEnd = new Date(breakStart.getTime() + 30 * 60 * 1000);

    await prisma.attendance.update({
      where: { id: ongoing.id },
      data: { break_start: breakStart, break_end: breakEnd },
    });

    return { id: ongoing.id, status: 200, message: 'Přestávka zaznamenána', auditAction: 'update' as const, auditDescription: 'Zaznamenána přestávka' };
  }

  return { error: 'Neplatná akce' };
}

export async function createAttendance(data: CreateAttendanceData, authUserId: number) {
  const record = await prisma.attendance.create({
    data: {
      user_id: data.user_id ?? authUserId,
      shift_date: new Date(data.shift_date),
      arrival_time: data.arrival_time ? new Date(data.arrival_time) : null,
      arrival_lat: data.arrival_lat ?? null,
      arrival_lng: data.arrival_lng ?? null,
      arrival_accuracy: data.arrival_accuracy ?? null,
      arrival_address: data.arrival_address ?? null,
      departure_time: data.departure_time ? new Date(data.departure_time) : null,
      departure_lat: data.departure_lat ?? null,
      departure_lng: data.departure_lng ?? null,
      departure_accuracy: data.departure_accuracy ?? null,
      departure_address: data.departure_address ?? null,
      notes: data.notes ?? null,
      project_id: data.project_id ?? null,
      leave_type: data.leave_type as attendance_leave_type,
      leave_hours: data.leave_hours ?? null,
    },
  });

  if (Array.isArray(data.project_logs)) {
    const logs = data.project_logs
      .filter(l => l.project_id && (Number(l.hours) > 0 || Number(l.minutes) > 0));
    if (logs.length > 0) {
      await prisma.attendance_project_logs.createMany({
        data: logs.map(l => ({
          attendance_id: record.id,
          project_id: Number(l.project_id),
          hours: Number(l.hours) || 0,
          minutes: Number(l.minutes) || 0,
        })),
      });
    }
  }

  return { id: record.id };
}

export async function updateAttendance(id: number, data: UpdateAttendanceData, authUserId: number, isAdmin: boolean) {
  const existing = await prisma.attendance.findUnique({ where: { id } });
  if (!existing) return { error: 'Záznam nenalezen', status: 404 };

  if (existing.user_id !== authUserId && !isAdmin) {
    return { error: 'Nemáte oprávnění upravit tento záznam', status: 403 };
  }

  await prisma.attendance.update({
    where: { id },
    data: {
      arrival_time: data.arrival_time !== undefined ? (data.arrival_time ? new Date(String(data.arrival_time)) : null) : undefined,
      departure_time: data.departure_time !== undefined ? (data.departure_time ? new Date(String(data.departure_time)) : null) : undefined,
      break_start: data.break_start !== undefined ? (data.break_start ? new Date(String(data.break_start)) : null) : undefined,
      break_end: data.break_end !== undefined ? (data.break_end ? new Date(String(data.break_end)) : null) : undefined,
      notes: data.notes !== undefined ? (data.notes ? String(data.notes) : null) : undefined,
      project_id: data.project_id !== undefined ? (data.project_id ? Number(data.project_id) : null) : undefined,
      leave_type: data.leave_type !== undefined ? String(data.leave_type) as attendance_leave_type : undefined,
      leave_hours: data.leave_hours !== undefined ? (data.leave_hours ? Number(data.leave_hours) : null) : undefined,
    },
  });

  if (Array.isArray(data.project_logs)) {
    await prisma.attendance_project_logs.deleteMany({ where: { attendance_id: id } });
    const logs = data.project_logs
      .filter(l => l.project_id && (Number(l.hours) > 0 || Number(l.minutes) > 0));
    if (logs.length > 0) {
      await prisma.attendance_project_logs.createMany({
        data: logs.map(l => ({
          attendance_id: id,
          project_id: Number(l.project_id),
          hours: Number(l.hours) || 0,
          minutes: Number(l.minutes) || 0,
        })),
      });
    }
  }

  return { id };
}

export async function deleteAttendance(id: number) {
  const existing = await prisma.attendance.findUnique({ where: { id } });
  if (!existing) return { error: 'Záznam nenalezen' };

  await prisma.attendance.delete({ where: { id } });
  return { success: true };
}