import 'package:flutter/material.dart';
import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:geolocator/geolocator.dart';

import '../../models/attendance_log.dart';
import '../../models/duty_schedule.dart';
import '../../models/pass_slip.dart';
import '../../models/profile.dart';
import '../../providers/attendance_provider.dart';
import '../../providers/notifications_provider.dart';
import '../../providers/pass_slip_provider.dart';
import '../../providers/profile_provider.dart';
import '../../providers/reports_provider.dart';
import '../../providers/whereabouts_provider.dart';
import '../../providers/workforce_provider.dart';
import '../../theme/m3_motion.dart';
import '../../utils/app_time.dart';
import '../../widgets/responsive_body.dart';

class AttendanceScreen extends ConsumerStatefulWidget {
  const AttendanceScreen({super.key});

  @override
  ConsumerState<AttendanceScreen> createState() => _AttendanceScreenState();
}

class _AttendanceScreenState extends ConsumerState<AttendanceScreen>
    with SingleTickerProviderStateMixin {
  late TabController _tabController;

  @override
  void initState() {
    super.initState();
    _tabController = TabController(length: 3, vsync: this);
  }

  @override
  void dispose() {
    _tabController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);

    return ResponsiveBody(
      child: Column(
        children: [
          Padding(
            padding: const EdgeInsets.fromLTRB(16, 12, 16, 0),
            child: Row(
              children: [
                Expanded(
                  child: Text(
                    'Attendance',
                    style: theme.textTheme.titleLarge?.copyWith(
                      fontWeight: FontWeight.w700,
                    ),
                  ),
                ),
              ],
            ),
          ),
          TabBar(
            controller: _tabController,
            tabs: const [
              Tab(text: 'Check In'),
              Tab(text: 'Logbook'),
              Tab(text: 'Pass Slip'),
            ],
          ),
          Expanded(
            child: TabBarView(
              controller: _tabController,
              children: const [_CheckInTab(), _LogbookTab(), _PassSlipTab()],
            ),
          ),
        ],
      ),
    );
  }
}

// ────────────────────────────────────────────────
// Tab 1 – Check In / Check Out
// ────────────────────────────────────────────────

class _CheckInTab extends ConsumerStatefulWidget {
  const _CheckInTab();

  @override
  ConsumerState<_CheckInTab> createState() => _CheckInTabState();
}

class _CheckInTabState extends ConsumerState<_CheckInTab> {
  bool _loading = false;

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final colors = theme.colorScheme;
    final profile = ref.watch(currentProfileProvider).valueOrNull;
    final schedulesAsync = ref.watch(dutySchedulesProvider);
    final logsAsync = ref.watch(attendanceLogsProvider);
    final allowTracking = profile?.allowTracking ?? false;

    if (profile == null) {
      return const Center(child: CircularProgressIndicator());
    }

    final now = AppTime.now();
    final today = DateTime(now.year, now.month, now.day);

    // Find today's schedule for the current user
    final schedules = schedulesAsync.valueOrNull ?? [];
    final todaySchedule = schedules.where((s) {
      final sDay = DateTime(
        s.startTime.year,
        s.startTime.month,
        s.startTime.day,
      );
      return s.userId == profile.id && sDay == today;
    }).toList();

    // Find active attendance log (checked in but not out)
    final logs = logsAsync.valueOrNull ?? [];
    final activeLog = logs
        .where((l) => l.userId == profile.id && !l.isCheckedOut)
        .toList();

    return SingleChildScrollView(
      padding: const EdgeInsets.all(16),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        children: [
          // Location tracking toggle
          Card(
            child: Padding(
              padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 8),
              child: Row(
                children: [
                  Icon(
                    Icons.location_on,
                    size: 20,
                    color: allowTracking ? colors.primary : colors.outline,
                  ),
                  const SizedBox(width: 8),
                  Expanded(
                    child: Text(
                      'Location Tracking',
                      style: theme.textTheme.bodyMedium,
                    ),
                  ),
                  Switch(
                    value: allowTracking,
                    onChanged: (v) =>
                        ref.read(whereaboutsControllerProvider).setTracking(v),
                  ),
                ],
              ),
            ),
          ),
          const SizedBox(height: 16),

          // Today's schedule
          Text(
            "Today's Schedule",
            style: theme.textTheme.titleMedium?.copyWith(
              fontWeight: FontWeight.w600,
            ),
          ),
          const SizedBox(height: 8),

          if (todaySchedule.isEmpty)
            Card(
              child: Padding(
                padding: const EdgeInsets.all(24),
                child: Center(
                  child: Text(
                    'No schedule assigned for today.',
                    style: theme.textTheme.bodyMedium?.copyWith(
                      color: colors.onSurfaceVariant,
                    ),
                  ),
                ),
              ),
            )
          else
            ...todaySchedule.map((schedule) {
              final hasCheckedIn = schedule.checkInAt != null;
              final isActive = activeLog.any(
                (l) => l.dutyScheduleId == schedule.id,
              );
              final completedLog = logs
                  .where(
                    (l) => l.dutyScheduleId == schedule.id && l.isCheckedOut,
                  )
                  .toList();
              final isCompleted = completedLog.isNotEmpty;

              return Card(
                child: Padding(
                  padding: const EdgeInsets.all(16),
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Row(
                        children: [
                          Icon(Icons.schedule, size: 20, color: colors.primary),
                          const SizedBox(width: 8),
                          Expanded(
                            child: Text(
                              _shiftLabel(schedule.shiftType),
                              style: theme.textTheme.titleSmall?.copyWith(
                                fontWeight: FontWeight.w600,
                              ),
                            ),
                          ),
                          _statusChip(
                            context,
                            isCompleted
                                ? 'Completed'
                                : isActive
                                ? 'On Duty'
                                : hasCheckedIn
                                ? 'Checked In'
                                : 'Scheduled',
                          ),
                        ],
                      ),
                      const SizedBox(height: 8),
                      Text(
                        '${AppTime.formatTime(schedule.startTime)} – ${AppTime.formatTime(schedule.endTime)}',
                        style: theme.textTheme.bodyMedium,
                      ),
                      const SizedBox(height: 12),
                      if (!hasCheckedIn && !isCompleted)
                        SizedBox(
                          width: double.infinity,
                          child: FilledButton.icon(
                            onPressed: _loading
                                ? null
                                : () => _handleCheckIn(schedule),
                            icon: _loading
                                ? const SizedBox(
                                    width: 16,
                                    height: 16,
                                    child: CircularProgressIndicator(
                                      strokeWidth: 2,
                                    ),
                                  )
                                : const Icon(Icons.login),
                            label: const Text('Check In'),
                          ),
                        )
                      else if (isActive)
                        SizedBox(
                          width: double.infinity,
                          child: FilledButton.tonalIcon(
                            onPressed: _loading
                                ? null
                                : () => _handleCheckOut(
                                    activeLog.firstWhere(
                                      (l) => l.dutyScheduleId == schedule.id,
                                    ),
                                  ),
                            icon: _loading
                                ? const SizedBox(
                                    width: 16,
                                    height: 16,
                                    child: CircularProgressIndicator(
                                      strokeWidth: 2,
                                    ),
                                  )
                                : const Icon(Icons.logout),
                            label: const Text('Check Out'),
                          ),
                        )
                      else if (isCompleted)
                        Row(
                          children: [
                            Icon(
                              Icons.check_circle,
                              size: 16,
                              color: colors.primary,
                            ),
                            const SizedBox(width: 6),
                            Expanded(
                              child: Text(
                                'Checked out at ${AppTime.formatTime(completedLog.first.checkOutAt!)}',
                                style: theme.textTheme.bodySmall?.copyWith(
                                  color: colors.onSurfaceVariant,
                                ),
                              ),
                            ),
                          ],
                        ),
                    ],
                  ),
                ),
              );
            }),
        ],
      ),
    );
  }

  Future<void> _handleCheckIn(DutySchedule schedule) async {
    setState(() => _loading = true);
    try {
      final geoCfg = await ref.read(geofenceProvider.future);
      final position = await Geolocator.getCurrentPosition(
        locationSettings: const LocationSettings(
          accuracy: LocationAccuracy.high,
        ),
      );
      // Client-side geofence check
      if (geoCfg != null) {
        bool inside = false;
        if (geoCfg.hasPolygon) {
          inside = geoCfg.containsPolygon(
            position.latitude,
            position.longitude,
          );
        } else if (geoCfg.hasCircle) {
          final dist = Geolocator.distanceBetween(
            position.latitude,
            position.longitude,
            geoCfg.lat!,
            geoCfg.lng!,
          );
          inside = dist <= (geoCfg.radiusMeters ?? 0);
        }
        if (!inside && mounted) {
          ScaffoldMessenger.of(context).showSnackBar(
            const SnackBar(content: Text('You are outside the geofence area.')),
          );
          return;
        }
      }
      await ref
          .read(attendanceControllerProvider)
          .checkIn(
            dutyScheduleId: schedule.id,
            lat: position.latitude,
            lng: position.longitude,
          );
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(content: Text('Checked in successfully.')),
        );
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(SnackBar(content: Text('Check-in failed: $e')));
      }
    } finally {
      if (mounted) setState(() => _loading = false);
    }
  }

  Future<void> _handleCheckOut(AttendanceLog log) async {
    setState(() => _loading = true);
    try {
      final position = await Geolocator.getCurrentPosition(
        locationSettings: const LocationSettings(
          accuracy: LocationAccuracy.high,
        ),
      );
      await ref
          .read(attendanceControllerProvider)
          .checkOut(
            attendanceId: log.id,
            lat: position.latitude,
            lng: position.longitude,
          );
      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(content: Text('Checked out successfully.')),
        );
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(SnackBar(content: Text('Check-out failed: $e')));
      }
    } finally {
      if (mounted) setState(() => _loading = false);
    }
  }

  Widget _statusChip(BuildContext context, String label) {
    final colors = Theme.of(context).colorScheme;
    Color bg;
    Color fg;
    switch (label) {
      case 'Completed':
        bg = colors.primaryContainer;
        fg = colors.onPrimaryContainer;
      case 'On Duty':
        bg = colors.tertiaryContainer;
        fg = colors.onTertiaryContainer;
      case 'Checked In':
        bg = colors.secondaryContainer;
        fg = colors.onSecondaryContainer;
      default:
        bg = colors.surfaceContainerHighest;
        fg = colors.onSurface;
    }
    return Container(
      padding: const EdgeInsets.symmetric(horizontal: 10, vertical: 4),
      decoration: BoxDecoration(
        color: bg,
        borderRadius: BorderRadius.circular(12),
      ),
      child: Text(
        label,
        style: Theme.of(context).textTheme.labelSmall?.copyWith(color: fg),
      ),
    );
  }

  String _shiftLabel(String shiftType) {
    switch (shiftType) {
      case 'normal':
        return 'Normal Shift';
      case 'night':
        return 'Night Shift';
      case 'overtime':
        return 'Overtime';
      default:
        return shiftType;
    }
  }
}

// ────────────────────────────────────────────────
// Tab 2 – Logbook
// ────────────────────────────────────────────────

class _LogbookTab extends ConsumerWidget {
  const _LogbookTab();

  @override
  Widget build(BuildContext context, WidgetRef ref) {
    final theme = Theme.of(context);
    final colors = theme.colorScheme;
    final range = ref.watch(attendanceDateRangeProvider);
    final logsAsync = ref.watch(attendanceLogsProvider);
    final profilesAsync = ref.watch(profilesProvider);

    final Map<String, Profile> profileById = {
      for (final p in profilesAsync.valueOrNull ?? []) p.id: p,
    };

    return Column(
      children: [
        // Date filter card
        Padding(
          padding: const EdgeInsets.fromLTRB(16, 12, 16, 0),
          child: Card(
            child: Padding(
              padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 8),
              child: Row(
                children: [
                  Icon(Icons.calendar_today, size: 18, color: colors.primary),
                  const SizedBox(width: 8),
                  Expanded(
                    child: Column(
                      crossAxisAlignment: CrossAxisAlignment.start,
                      mainAxisSize: MainAxisSize.min,
                      children: [
                        Text(range.label, style: theme.textTheme.labelLarge),
                        Text(
                          AppTime.formatDateRange(range.dateTimeRange),
                          style: theme.textTheme.bodySmall?.copyWith(
                            color: colors.onSurfaceVariant,
                          ),
                        ),
                      ],
                    ),
                  ),
                  FilledButton.tonalIcon(
                    onPressed: () => _showDateFilterDialog(context, ref),
                    icon: const Icon(Icons.tune, size: 18),
                    label: const Text('Change'),
                  ),
                ],
              ),
            ),
          ),
        ),
        const SizedBox(height: 8),
        Expanded(
          child: logsAsync.when(
            data: (logs) {
              final filtered = logs.where((log) {
                return !log.checkInAt.isBefore(range.start) &&
                    log.checkInAt.isBefore(range.end);
              }).toList();

              if (filtered.isEmpty) {
                return Center(
                  child: Text(
                    'No attendance logs for this period.',
                    style: theme.textTheme.bodyMedium?.copyWith(
                      color: colors.onSurfaceVariant,
                    ),
                  ),
                );
              }

              return LayoutBuilder(
                builder: (context, constraints) {
                  if (constraints.maxWidth >= 700) {
                    return _buildDataTable(context, filtered, profileById);
                  }
                  return _buildLogList(context, filtered, profileById);
                },
              );
            },
            loading: () => const Center(child: CircularProgressIndicator()),
            error: (e, _) => Center(child: Text('Failed to load logs: $e')),
          ),
        ),
      ],
    );
  }

  void _showDateFilterDialog(BuildContext context, WidgetRef ref) {
    m3ShowDialog(
      context: context,
      builder: (ctx) => _AttendanceDateFilterDialog(
        current: ref.read(attendanceDateRangeProvider),
        onApply: (newRange) {
          ref.read(attendanceDateRangeProvider.notifier).state = newRange;
        },
      ),
    );
  }

  Widget _buildDataTable(
    BuildContext context,
    List<AttendanceLog> logs,
    Map<String, Profile> profileById,
  ) {
    return SingleChildScrollView(
      padding: const EdgeInsets.symmetric(horizontal: 16),
      child: DataTable(
        columns: const [
          DataColumn(label: Text('Staff')),
          DataColumn(label: Text('Role')),
          DataColumn(label: Text('Date')),
          DataColumn(label: Text('Check In')),
          DataColumn(label: Text('Check Out')),
          DataColumn(label: Text('Duration')),
          DataColumn(label: Text('Status')),
        ],
        rows: logs.map((log) {
          final p = profileById[log.userId];
          final name = p?.fullName ?? log.userId;
          final role = p?.role ?? '-';
          final date = AppTime.formatDate(log.checkInAt);
          final checkIn = AppTime.formatTime(log.checkInAt);
          final checkOut = log.isCheckedOut
              ? AppTime.formatTime(log.checkOutAt!)
              : '—';
          final duration = log.isCheckedOut
              ? _formatDuration(log.checkOutAt!.difference(log.checkInAt))
              : 'On duty';
          final status = log.isCheckedOut ? 'Completed' : 'On duty';

          return DataRow(
            cells: [
              DataCell(Text(name)),
              DataCell(Text(_roleLabel(role))),
              DataCell(Text(date)),
              DataCell(Text(checkIn)),
              DataCell(Text(checkOut)),
              DataCell(Text(duration)),
              DataCell(
                Text(
                  status,
                  style: TextStyle(
                    color: log.isCheckedOut ? Colors.green : Colors.orange,
                  ),
                ),
              ),
            ],
          );
        }).toList(),
      ),
    );
  }

  Widget _buildLogList(
    BuildContext context,
    List<AttendanceLog> logs,
    Map<String, Profile> profileById,
  ) {
    return ListView.builder(
      padding: const EdgeInsets.symmetric(horizontal: 16),
      itemCount: logs.length,
      itemBuilder: (context, index) {
        final log = logs[index];
        final p = profileById[log.userId];
        final name = p?.fullName ?? log.userId;
        final role = p?.role ?? '-';

        return Card(
          child: ListTile(
            title: Text(name),
            subtitle: Text(
              '${_roleLabel(role)} · ${AppTime.formatDate(log.checkInAt)}\n'
              'In: ${AppTime.formatTime(log.checkInAt)}'
              '${log.isCheckedOut ? " · Out: ${AppTime.formatTime(log.checkOutAt!)}" : " · On duty"}',
            ),
            isThreeLine: true,
            trailing: log.isCheckedOut
                ? Text(
                    _formatDuration(log.checkOutAt!.difference(log.checkInAt)),
                    style: Theme.of(context).textTheme.bodySmall,
                  )
                : Chip(
                    label: const Text('On duty'),
                    backgroundColor: Theme.of(
                      context,
                    ).colorScheme.tertiaryContainer,
                  ),
          ),
        );
      },
    );
  }

  String _formatDuration(Duration d) {
    final hours = d.inHours;
    final minutes = d.inMinutes.remainder(60);
    return '${hours}h ${minutes}m';
  }

  String _roleLabel(String role) {
    switch (role) {
      case 'admin':
        return 'Admin';
      case 'dispatcher':
        return 'Dispatcher';
      case 'it_staff':
        return 'IT Staff';
      default:
        return 'Standard';
    }
  }
}

// ────────────────────────────────────────────────
// Date filter dialog (reuses Metabase-style pattern)
// ────────────────────────────────────────────────

class _AttendanceDateFilterDialog extends StatefulWidget {
  const _AttendanceDateFilterDialog({
    required this.current,
    required this.onApply,
  });

  final ReportDateRange current;
  final ValueChanged<ReportDateRange> onApply;

  @override
  State<_AttendanceDateFilterDialog> createState() =>
      _AttendanceDateFilterDialogState();
}

class _AttendanceDateFilterDialogState
    extends State<_AttendanceDateFilterDialog>
    with SingleTickerProviderStateMixin {
  late TabController _tabCtrl;
  int _relativeAmount = 7;
  String _relativeUnit = 'days';
  DateTime? _customStart;
  DateTime? _customEnd;

  static const _units = ['days', 'weeks', 'months', 'quarters', 'years'];

  @override
  void initState() {
    super.initState();
    _tabCtrl = TabController(length: 3, vsync: this);
    _customStart = widget.current.start;
    _customEnd = widget.current.end;
  }

  @override
  void dispose() {
    _tabCtrl.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final colors = theme.colorScheme;
    final text = theme.textTheme;

    return Dialog(
      shape: RoundedRectangleBorder(borderRadius: BorderRadius.circular(20)),
      child: ConstrainedBox(
        constraints: const BoxConstraints(maxWidth: 440, maxHeight: 520),
        child: Column(
          mainAxisSize: MainAxisSize.min,
          children: [
            Padding(
              padding: const EdgeInsets.fromLTRB(20, 16, 20, 0),
              child: Row(
                children: [
                  Icon(Icons.date_range, color: colors.primary),
                  const SizedBox(width: 8),
                  Text('Filter Date Range', style: text.titleMedium),
                  const Spacer(),
                  IconButton(
                    icon: const Icon(Icons.close, size: 20),
                    onPressed: () => Navigator.pop(context),
                  ),
                ],
              ),
            ),
            TabBar(
              controller: _tabCtrl,
              labelStyle: text.labelMedium,
              tabs: const [
                Tab(text: 'Presets'),
                Tab(text: 'Relative'),
                Tab(text: 'Custom'),
              ],
            ),
            Flexible(
              child: TabBarView(
                controller: _tabCtrl,
                children: [
                  _buildPresetsTab(context),
                  _buildRelativeTab(context),
                  _buildCustomTab(context),
                ],
              ),
            ),
          ],
        ),
      ),
    );
  }

  Widget _buildPresetsTab(BuildContext context) {
    final now = AppTime.now();
    final today = DateTime(now.year, now.month, now.day);

    final presets = <_Preset>[
      _Preset('Today', today, today.add(const Duration(days: 1))),
      _Preset('Yesterday', today.subtract(const Duration(days: 1)), today),
      _Preset(
        'Last 7 Days',
        today.subtract(const Duration(days: 7)),
        today.add(const Duration(days: 1)),
      ),
      _Preset(
        'Last 30 Days',
        today.subtract(const Duration(days: 30)),
        today.add(const Duration(days: 1)),
      ),
      _Preset(
        'Last 90 Days',
        today.subtract(const Duration(days: 90)),
        today.add(const Duration(days: 1)),
      ),
      _Preset(
        'This Week',
        today.subtract(Duration(days: today.weekday - 1)),
        today.add(const Duration(days: 1)),
      ),
      _Preset(
        'This Month',
        DateTime(now.year, now.month, 1),
        DateTime(now.year, now.month + 1, 1),
      ),
      _Preset(
        'This Year',
        DateTime(now.year, 1, 1),
        DateTime(now.year + 1, 1, 1),
      ),
    ];

    return SingleChildScrollView(
      padding: const EdgeInsets.all(16),
      child: Wrap(
        spacing: 8,
        runSpacing: 8,
        children: presets.map((p) {
          final isSelected = widget.current.label == p.label;
          return ChoiceChip(
            label: Text(p.label),
            selected: isSelected,
            onSelected: (_) {
              widget.onApply(
                ReportDateRange(start: p.start, end: p.end, label: p.label),
              );
              Navigator.pop(context);
            },
          );
        }).toList(),
      ),
    );
  }

  Widget _buildRelativeTab(BuildContext context) {
    final theme = Theme.of(context);
    final text = theme.textTheme;
    final preview = _computeRelativeRange(_relativeAmount, _relativeUnit);
    final previewText = AppTime.formatDateRange(preview.dateTimeRange);

    return Padding(
      padding: const EdgeInsets.all(20),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        mainAxisSize: MainAxisSize.min,
        children: [
          Text('Previous', style: text.labelLarge),
          const SizedBox(height: 12),
          Row(
            children: [
              SizedBox(
                width: 80,
                child: TextFormField(
                  initialValue: _relativeAmount.toString(),
                  keyboardType: TextInputType.number,
                  decoration: const InputDecoration(
                    isDense: true,
                    contentPadding: EdgeInsets.symmetric(
                      horizontal: 12,
                      vertical: 10,
                    ),
                  ),
                  onChanged: (v) => setState(() {
                    _relativeAmount = int.tryParse(v) ?? _relativeAmount;
                  }),
                ),
              ),
              const SizedBox(width: 12),
              Expanded(
                child: DropdownButtonFormField<String>(
                  initialValue: _relativeUnit,
                  decoration: const InputDecoration(
                    isDense: true,
                    contentPadding: EdgeInsets.symmetric(
                      horizontal: 12,
                      vertical: 10,
                    ),
                  ),
                  items: _units
                      .map((u) => DropdownMenuItem(value: u, child: Text(u)))
                      .toList(),
                  onChanged: (v) {
                    if (v != null) setState(() => _relativeUnit = v);
                  },
                ),
              ),
              const SizedBox(width: 12),
              Text('ago', style: text.bodyLarge),
            ],
          ),
          const SizedBox(height: 16),
          Text(
            previewText,
            style: text.bodyMedium?.copyWith(
              color: theme.colorScheme.onSurfaceVariant,
            ),
          ),
          const SizedBox(height: 20),
          Align(
            alignment: Alignment.centerRight,
            child: FilledButton(
              onPressed: () {
                widget.onApply(preview);
                Navigator.pop(context);
              },
              child: const Text('Apply'),
            ),
          ),
        ],
      ),
    );
  }

  ReportDateRange _computeRelativeRange(int amount, String unit) {
    final now = AppTime.now();
    final end = now;
    DateTime start;
    switch (unit) {
      case 'days':
        start = now.subtract(Duration(days: amount));
      case 'weeks':
        start = now.subtract(Duration(days: amount * 7));
      case 'months':
        start = DateTime(now.year, now.month - amount, now.day);
      case 'quarters':
        start = DateTime(now.year, now.month - (amount * 3), now.day);
      case 'years':
        start = DateTime(now.year - amount, now.month, now.day);
      default:
        start = now.subtract(Duration(days: amount));
    }
    return ReportDateRange(start: start, end: end, label: 'Last $amount $unit');
  }

  Widget _buildCustomTab(BuildContext context) {
    final theme = Theme.of(context);
    final text = theme.textTheme;

    return Padding(
      padding: const EdgeInsets.all(20),
      child: Column(
        crossAxisAlignment: CrossAxisAlignment.start,
        mainAxisSize: MainAxisSize.min,
        children: [
          Text('Start Date', style: text.labelLarge),
          const SizedBox(height: 8),
          OutlinedButton.icon(
            icon: const Icon(Icons.calendar_today, size: 16),
            label: Text(
              _customStart != null
                  ? AppTime.formatDate(_customStart!)
                  : 'Select start date',
            ),
            onPressed: () async {
              final picked = await showDatePicker(
                context: context,
                initialDate: _customStart ?? AppTime.now(),
                firstDate: DateTime(2020),
                lastDate: DateTime(2030),
              );
              if (picked != null) setState(() => _customStart = picked);
            },
          ),
          const SizedBox(height: 16),
          Text('End Date', style: text.labelLarge),
          const SizedBox(height: 8),
          OutlinedButton.icon(
            icon: const Icon(Icons.calendar_today, size: 16),
            label: Text(
              _customEnd != null
                  ? AppTime.formatDate(_customEnd!)
                  : 'Select end date',
            ),
            onPressed: () async {
              final picked = await showDatePicker(
                context: context,
                initialDate: _customEnd ?? AppTime.now(),
                firstDate: DateTime(2020),
                lastDate: DateTime(2030),
              );
              if (picked != null) setState(() => _customEnd = picked);
            },
          ),
          const SizedBox(height: 20),
          Align(
            alignment: Alignment.centerRight,
            child: FilledButton(
              onPressed: (_customStart != null && _customEnd != null)
                  ? () {
                      widget.onApply(
                        ReportDateRange(
                          start: _customStart!,
                          end: _customEnd!,
                          label: 'Custom',
                        ),
                      );
                      Navigator.pop(context);
                    }
                  : null,
              child: const Text('Apply'),
            ),
          ),
        ],
      ),
    );
  }
}

class _Preset {
  const _Preset(this.label, this.start, this.end);
  final String label;
  final DateTime start;
  final DateTime end;
}

// ────────────────────────────────────────────────
// Tab 3 – Pass Slip
// ────────────────────────────────────────────────

class _PassSlipTab extends ConsumerStatefulWidget {
  const _PassSlipTab();

  @override
  ConsumerState<_PassSlipTab> createState() => _PassSlipTabState();
}

class _PassSlipTabState extends ConsumerState<_PassSlipTab> {
  final _reasonController = TextEditingController();
  bool _submitting = false;

  @override
  void dispose() {
    _reasonController.dispose();
    super.dispose();
  }

  @override
  Widget build(BuildContext context) {
    final theme = Theme.of(context);
    final colors = theme.colorScheme;
    final profile = ref.watch(currentProfileProvider).valueOrNull;
    final slipsAsync = ref.watch(passSlipsProvider);
    final schedulesAsync = ref.watch(dutySchedulesProvider);
    final profilesAsync = ref.watch(profilesProvider);
    final activeSlip = ref.watch(activePassSlipProvider);
    final isAdmin = profile?.role == 'admin' || profile?.role == 'dispatcher';

    final Map<String, Profile> profileById = {
      for (final p in profilesAsync.valueOrNull ?? []) p.id: p,
    };

    if (profile == null) {
      return const Center(child: CircularProgressIndicator());
    }

    // Find today's schedule for passing to request form
    final now = AppTime.now();
    final today = DateTime(now.year, now.month, now.day);
    final schedules = schedulesAsync.valueOrNull ?? [];
    final todaySchedule = schedules.where((s) {
      final sDay = DateTime(
        s.startTime.year,
        s.startTime.month,
        s.startTime.day,
      );
      return s.userId == profile.id && sDay == today;
    }).toList();

    return slipsAsync.when(
      data: (slips) {
        return ListView(
          padding: const EdgeInsets.all(16),
          children: [
            // Active slip banner
            if (activeSlip != null) ...[
              Card(
                color: activeSlip.isExceeded
                    ? colors.errorContainer
                    : colors.tertiaryContainer,
                child: Padding(
                  padding: const EdgeInsets.all(16),
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      Row(
                        children: [
                          Icon(
                            activeSlip.isExceeded
                                ? Icons.warning
                                : Icons.directions_walk,
                            color: activeSlip.isExceeded
                                ? colors.onErrorContainer
                                : colors.onTertiaryContainer,
                          ),
                          const SizedBox(width: 8),
                          Expanded(
                            child: Text(
                              activeSlip.isExceeded
                                  ? 'Pass Slip Exceeded (>1 hour)'
                                  : 'Active Pass Slip',
                              style: theme.textTheme.titleSmall?.copyWith(
                                fontWeight: FontWeight.w600,
                                color: activeSlip.isExceeded
                                    ? colors.onErrorContainer
                                    : colors.onTertiaryContainer,
                              ),
                            ),
                          ),
                        ],
                      ),
                      const SizedBox(height: 8),
                      Text(
                        'Reason: ${activeSlip.reason}',
                        style: theme.textTheme.bodyMedium,
                      ),
                      if (activeSlip.slipStart != null)
                        Text(
                          'Started: ${AppTime.formatTime(activeSlip.slipStart!)}',
                          style: theme.textTheme.bodySmall,
                        ),
                      const SizedBox(height: 12),
                      SizedBox(
                        width: double.infinity,
                        child: FilledButton.icon(
                          onPressed: _submitting
                              ? null
                              : () => _completeSlip(activeSlip.id),
                          icon: const Icon(Icons.check),
                          label: const Text('Complete / Return'),
                        ),
                      ),
                    ],
                  ),
                ),
              ),
              const SizedBox(height: 16),
            ],

            // Request form (only for non-admin staff with a schedule today)
            if (!isAdmin && activeSlip == null && todaySchedule.isNotEmpty) ...[
              Text(
                'Request Pass Slip',
                style: theme.textTheme.titleMedium?.copyWith(
                  fontWeight: FontWeight.w600,
                ),
              ),
              const SizedBox(height: 8),
              Card(
                child: Padding(
                  padding: const EdgeInsets.all(16),
                  child: Column(
                    crossAxisAlignment: CrossAxisAlignment.start,
                    children: [
                      TextField(
                        controller: _reasonController,
                        decoration: const InputDecoration(
                          labelText: 'Reason',
                          hintText: 'Brief reason for pass slip',
                        ),
                        maxLines: 2,
                      ),
                      const SizedBox(height: 12),
                      SizedBox(
                        width: double.infinity,
                        child: FilledButton.tonalIcon(
                          onPressed: _submitting
                              ? null
                              : () => _requestSlip(todaySchedule.first.id),
                          icon: _submitting
                              ? const SizedBox(
                                  width: 16,
                                  height: 16,
                                  child: CircularProgressIndicator(
                                    strokeWidth: 2,
                                  ),
                                )
                              : const Icon(Icons.send),
                          label: const Text('Submit Request'),
                        ),
                      ),
                    ],
                  ),
                ),
              ),
              const SizedBox(height: 16),
            ],

            // Pending slips for admin approval
            if (isAdmin) ...[
              Text(
                'Pending Approvals',
                style: theme.textTheme.titleMedium?.copyWith(
                  fontWeight: FontWeight.w600,
                ),
              ),
              const SizedBox(height: 8),
              ...slips
                  .where((s) => s.status == 'pending')
                  .map(
                    (slip) => _buildSlipCard(
                      context,
                      slip,
                      profileById,
                      showActions: true,
                    ),
                  ),
              if (slips.where((s) => s.status == 'pending').isEmpty)
                Padding(
                  padding: const EdgeInsets.symmetric(vertical: 8),
                  child: Text(
                    'No pending pass slip requests.',
                    style: theme.textTheme.bodyMedium?.copyWith(
                      color: colors.onSurfaceVariant,
                    ),
                  ),
                ),
              const SizedBox(height: 16),
            ],

            // History
            Text(
              'Pass Slip History',
              style: theme.textTheme.titleMedium?.copyWith(
                fontWeight: FontWeight.w600,
              ),
            ),
            const SizedBox(height: 8),
            ...slips
                .where((s) => s.status != 'pending' || !isAdmin)
                .take(50)
                .map(
                  (slip) => _buildSlipCard(
                    context,
                    slip,
                    profileById,
                    showActions: false,
                  ),
                ),
            if (slips.isEmpty)
              Center(
                child: Padding(
                  padding: const EdgeInsets.symmetric(vertical: 24),
                  child: Text(
                    'No pass slip records.',
                    style: theme.textTheme.bodyMedium?.copyWith(
                      color: colors.onSurfaceVariant,
                    ),
                  ),
                ),
              ),
          ],
        );
      },
      loading: () => const Center(child: CircularProgressIndicator()),
      error: (e, _) => Center(child: Text('Failed to load pass slips: $e')),
    );
  }

  Widget _buildSlipCard(
    BuildContext context,
    PassSlip slip,
    Map<String, Profile> profileById, {
    required bool showActions,
  }) {
    final theme = Theme.of(context);
    final colors = theme.colorScheme;
    final p = profileById[slip.userId];
    final name = p?.fullName ?? slip.userId;

    Color statusColor;
    switch (slip.status) {
      case 'approved':
        statusColor = Colors.green;
      case 'rejected':
        statusColor = colors.error;
      case 'completed':
        statusColor = colors.primary;
      default:
        statusColor = Colors.orange;
    }

    return Card(
      child: Padding(
        padding: const EdgeInsets.all(12),
        child: Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: [
            Row(
              children: [
                Expanded(child: Text(name, style: theme.textTheme.titleSmall)),
                Container(
                  padding: const EdgeInsets.symmetric(
                    horizontal: 10,
                    vertical: 4,
                  ),
                  decoration: BoxDecoration(
                    color: statusColor.withValues(alpha: 0.15),
                    borderRadius: BorderRadius.circular(12),
                  ),
                  child: Text(
                    slip.status.toUpperCase(),
                    style: theme.textTheme.labelSmall?.copyWith(
                      color: statusColor,
                      fontWeight: FontWeight.w600,
                    ),
                  ),
                ),
              ],
            ),
            const SizedBox(height: 4),
            Text(slip.reason, style: theme.textTheme.bodyMedium),
            Text(
              'Requested: ${AppTime.formatDate(slip.requestedAt)} ${AppTime.formatTime(slip.requestedAt)}',
              style: theme.textTheme.bodySmall?.copyWith(
                color: colors.onSurfaceVariant,
              ),
            ),
            if (slip.slipStart != null)
              Text(
                'Started: ${AppTime.formatTime(slip.slipStart!)}'
                '${slip.slipEnd != null ? " · Ended: ${AppTime.formatTime(slip.slipEnd!)}" : ""}',
                style: theme.textTheme.bodySmall?.copyWith(
                  color: colors.onSurfaceVariant,
                ),
              ),
            if (showActions && slip.status == 'pending') ...[
              const SizedBox(height: 8),
              Row(
                mainAxisAlignment: MainAxisAlignment.end,
                children: [
                  TextButton(
                    onPressed: _submitting ? null : () => _rejectSlip(slip.id),
                    child: Text(
                      'Reject',
                      style: TextStyle(color: colors.error),
                    ),
                  ),
                  const SizedBox(width: 8),
                  FilledButton(
                    onPressed: _submitting ? null : () => _approveSlip(slip.id),
                    child: const Text('Approve'),
                  ),
                ],
              ),
            ],
          ],
        ),
      ),
    );
  }

  Future<void> _requestSlip(String scheduleId) async {
    final reason = _reasonController.text.trim();
    if (reason.isEmpty) {
      ScaffoldMessenger.of(
        context,
      ).showSnackBar(const SnackBar(content: Text('Please enter a reason.')));
      return;
    }
    setState(() => _submitting = true);
    try {
      await ref
          .read(passSlipControllerProvider)
          .requestSlip(dutyScheduleId: scheduleId, reason: reason);
      _reasonController.clear();

      // Notify all admin users via push notification
      final profiles = ref.read(profilesProvider).valueOrNull ?? [];
      final adminIds = profiles
          .where((p) => p.role == 'admin')
          .map((p) => p.id)
          .toList();
      final currentProfile = ref.read(currentProfileProvider).valueOrNull;
      final actorName = currentProfile?.fullName ?? 'A staff member';
      if (adminIds.isNotEmpty && currentProfile != null) {
        ref
            .read(notificationsControllerProvider)
            .createNotification(
              userIds: adminIds,
              type: 'pass_slip_request',
              actorId: currentProfile.id,
              pushTitle: 'Pass Slip Request',
              pushBody: '$actorName requested a pass slip: $reason',
            );
      }

      if (mounted) {
        ScaffoldMessenger.of(context).showSnackBar(
          const SnackBar(content: Text('Pass slip request submitted.')),
        );
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(SnackBar(content: Text('Failed: $e')));
      }
    } finally {
      if (mounted) setState(() => _submitting = false);
    }
  }

  Future<void> _approveSlip(String slipId) async {
    setState(() => _submitting = true);
    try {
      await ref.read(passSlipControllerProvider).approveSlip(slipId);
      if (mounted) {
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(const SnackBar(content: Text('Pass slip approved.')));
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(SnackBar(content: Text('Failed: $e')));
      }
    } finally {
      if (mounted) setState(() => _submitting = false);
    }
  }

  Future<void> _rejectSlip(String slipId) async {
    setState(() => _submitting = true);
    try {
      await ref.read(passSlipControllerProvider).rejectSlip(slipId);
      if (mounted) {
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(const SnackBar(content: Text('Pass slip rejected.')));
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(SnackBar(content: Text('Failed: $e')));
      }
    } finally {
      if (mounted) setState(() => _submitting = false);
    }
  }

  Future<void> _completeSlip(String slipId) async {
    setState(() => _submitting = true);
    try {
      await ref.read(passSlipControllerProvider).completeSlip(slipId);
      if (mounted) {
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(const SnackBar(content: Text('Pass slip completed.')));
      }
    } catch (e) {
      if (mounted) {
        ScaffoldMessenger.of(
          context,
        ).showSnackBar(SnackBar(content: Text('Failed: $e')));
      }
    } finally {
      if (mounted) setState(() => _submitting = false);
    }
  }
}