import 'dart:typed_data';

import 'package:flutter_riverpod/flutter_riverpod.dart';
import 'package:supabase_flutter/supabase_flutter.dart';

import '../models/attendance_log.dart';
import '../utils/app_time.dart';
import 'profile_provider.dart';
import 'reports_provider.dart';
import 'supabase_provider.dart';
import 'stream_recovery.dart';
import 'realtime_controller.dart';

/// Date range for attendance logbook, defaults to "Last 7 Days".
final attendanceDateRangeProvider = StateProvider<ReportDateRange>((ref) {
  final now = AppTime.now();
  final today = DateTime(now.year, now.month, now.day);
  return ReportDateRange(
    start: today,
    end: today.add(const Duration(days: 1)),
    label: 'Today',
  );
});

/// All visible attendance logs (own for standard, all for admin/dispatcher/it_staff).
final attendanceLogsProvider = StreamProvider<List<AttendanceLog>>((ref) {
  final client = ref.watch(supabaseClientProvider);
  final profileAsync = ref.watch(currentProfileProvider);
  final profile = profileAsync.valueOrNull;
  if (profile == null) return Stream.value(const <AttendanceLog>[]);

  final hasFullAccess =
      profile.role == 'admin' ||
      profile.role == 'dispatcher' ||
      profile.role == 'it_staff';

  final wrapper = StreamRecoveryWrapper<AttendanceLog>(
    stream: hasFullAccess
        ? client
              .from('attendance_logs')
              .stream(primaryKey: ['id'])
              .order('check_in_at', ascending: false)
        : client
              .from('attendance_logs')
              .stream(primaryKey: ['id'])
              .eq('user_id', profile.id)
              .order('check_in_at', ascending: false),
    onPollData: () async {
      final query = client.from('attendance_logs').select();
      final data = hasFullAccess
          ? await query.order('check_in_at', ascending: false)
          : await query
                .eq('user_id', profile.id)
                .order('check_in_at', ascending: false);
      return data.map(AttendanceLog.fromMap).toList();
    },
    fromMap: AttendanceLog.fromMap,
    channelName: 'attendance_logs',
    onStatusChanged: ref.read(realtimeControllerProvider).handleChannelStatus,
  );

  ref.onDispose(wrapper.dispose);
  return wrapper.stream.map((result) => result.data);
});

final attendanceControllerProvider = Provider<AttendanceController>((ref) {
  final client = ref.watch(supabaseClientProvider);
  return AttendanceController(client);
});

class AttendanceController {
  AttendanceController(this._client);

  final SupabaseClient _client;

  /// Check in to a duty schedule. Returns the attendance log ID.
  Future<String?> checkIn({
    required String dutyScheduleId,
    required double lat,
    required double lng,
  }) async {
    final data = await _client.rpc(
      'attendance_check_in',
      params: {'p_duty_id': dutyScheduleId, 'p_lat': lat, 'p_lng': lng},
    );
    return data as String?;
  }

  /// Check out from an attendance log.
  Future<void> checkOut({
    required String attendanceId,
    required double lat,
    required double lng,
    String? justification,
  }) async {
    await _client.rpc(
      'attendance_check_out',
      params: {
        'p_attendance_id': attendanceId,
        'p_lat': lat,
        'p_lng': lng,
        // ignore: use_null_aware_elements
        if (justification != null) 'p_justification': justification,
      },
    );
  }

  /// Overtime check-in (no pre-existing schedule required).
  /// Creates an overtime duty schedule + attendance log in one RPC call.
  Future<String?> overtimeCheckIn({
    required double lat,
    required double lng,
    String? justification,
  }) async {
    final data = await _client.rpc(
      'overtime_check_in',
      params: {'p_lat': lat, 'p_lng': lng, 'p_justification': justification},
    );
    return data as String?;
  }

  /// Upload a verification selfie and update the attendance log.
  Future<void> uploadVerification({
    required String attendanceId,
    required Uint8List bytes,
    required String fileName,
    required String status, // 'verified', 'unverified'
    bool isCheckOut = false,
  }) async {
    final userId = _client.auth.currentUser!.id;
    final ext = fileName.split('.').last.toLowerCase();
    final prefix = isCheckOut ? 'checkout' : 'checkin';
    final path = '$userId/${prefix}_$attendanceId.$ext';
    await _client.storage
        .from('attendance-verification')
        .uploadBinary(
          path,
          bytes,
          fileOptions: const FileOptions(upsert: true),
        );
    final url = _client.storage
        .from('attendance-verification')
        .getPublicUrl(path);
    final column = isCheckOut
        ? 'check_out_verification_photo_url'
        : 'check_in_verification_photo_url';
    await _client
        .from('attendance_logs')
        .update({'verification_status': status, column: url})
        .eq('id', attendanceId);
  }

  /// Mark an attendance log as skipped verification.
  Future<void> skipVerification(String attendanceId) async {
    await _client
        .from('attendance_logs')
        .update({'verification_status': 'skipped'})
        .eq('id', attendanceId);
  }
}