import 'dart:typed_data';
import 'dart:convert';
import 'package:http/http.dart' as http;
import '../models/work_day.dart';
import '../models/work_interval.dart';
import '../models/month_start.dart';
import '../utils/helpers.dart';

class BookingApi {
  final http.Client client;
  BookingApi({required this.client});

  /// Monatliche Buchungen holen (für YYYY-MM)
  Future<List<WorkDay>> getBookingList(DateTime monthStart) async {
    final y = monthStart.year.toString().padLeft(4, '0');
    final m = monthStart.month.toString().padLeft(2, '0');
    final uri = Uri.parse(
      'https://api.windesign.at/workinghours.php?module=booking&function=getList&date=$y-$m',
    );

    final res = await client.get(uri);
    if (res.statusCode != 200) {
      throw Exception('booking/getList failed: ${res.statusCode} ${res.body}');
    }
    final map = jsonDecode(res.body) as Map<String, dynamic>;
    if (map['error'] == true) {
      throw Exception('booking/getList error: ${map['errmsg']}');
    }
    final list = (map['bookings'] as List?) ?? const [];
    final items = <WorkDay>[];

    for (final e in list) {
      final row = e as Map<String, dynamic>;
      final dayStr = (row['bookingDay'] as String?) ?? '';
      final date = DateTime.tryParse(dayStr);
      if (date == null) continue;

      String? code = (row['code'] as String?)?.trim();
      if (code != null && code.isEmpty) code = null;

      final starts = <String?>[
        row['come1'] as String?, row['come2'] as String?,
        row['come3'] as String?, row['come4'] as String?, row['come5'] as String?,
      ];
      final ends = <String?>[
        row['leave1'] as String?, row['leave2'] as String?,
        row['leave3'] as String?, row['leave4'] as String?, row['leave5'] as String?,
      ];
      final intervals = <WorkInterval>[];
      for (int i = 0; i < 5; i++) {
        final s = parseDbTime(starts[i]);
        final e2 = parseDbTime(ends[i]);
        if (s != null && e2 != null) {
          intervals.add(WorkInterval(s, e2));
        }
      }

      items.add(WorkDay(
        date: DateTime(date.year, date.month, date.day),
        intervals: intervals,
        targetMinutes: 0, // wird im UI mit Tagesplan/Feiertag ersetzt
        code: code,
      ));
    }

    return items;
  }

  /// Monatliche Startdaten (Startsaldo, Vacation, Overtime, Correction)
  Future<MonthStart> getMonthStart(DateTime monthStart) async {
    final y = monthStart.year.toString().padLeft(4, '0');
    final m = monthStart.month.toString().padLeft(2, '0');
    final uri = Uri.parse(
      'https://api.windesign.at/workinghours.php'
      '?module=monthlybooking&function=getList&date=$y-$m-01',
    );
    final res = await client.get(uri);
    if (res.statusCode != 200) {
      throw Exception('monthlybooking/getList failed: ${res.statusCode} ${res.body}');
    }
    final map = jsonDecode(res.body) as Map<String, dynamic>;
    if (map['error'] == true) {
      throw Exception('monthlybooking/getList error: ${map['errmsg']}');
    }
    return MonthStart.fromJson(map);
  }

  /// Einen Tag speichern: date (YYYY-MM-DD), code, come1..leave5 ("HH:mm" oder null/leer)
  Future<void> saveDay(WorkDay day) async {
    final y = day.date.year.toString().padLeft(4, '0');
    final m = day.date.month.toString().padLeft(2, '0');
    final d = day.date.day.toString().padLeft(2, '0');
    final dateStr = '$y-$m-$d';

    // Intervalle in 5 Slots abbilden
    final starts = List<String?>.filled(5, null);
    final ends   = List<String?>.filled(5, null);
    for (int i = 0; i < day.intervals.length && i < 5; i++) {
      starts[i] = fmtTimeOfDay(day.intervals[i].start);
      ends[i]   = fmtTimeOfDay(day.intervals[i].end);
    }

    // Codes, die Zeiten serverseitig leeren
    final lockCodes = {'G', 'U', 'SU', 'K'};
    final payload = <String, dynamic>{
      'module': 'booking',
      'function': 'saveDay',
      'date': dateStr,
      'code': day.code, // null → wird als NULL gespeichert
      'come1': lockCodes.contains(day.code) ? null : starts[0],
      'leave1': lockCodes.contains(day.code) ? null : ends[0],
      'come2': lockCodes.contains(day.code) ? null : starts[1],
      'leave2': lockCodes.contains(day.code) ? null : ends[1],
      'come3': lockCodes.contains(day.code) ? null : starts[2],
      'leave3': lockCodes.contains(day.code) ? null : ends[2],
      'come4': lockCodes.contains(day.code) ? null : starts[3],
      'leave4': lockCodes.contains(day.code) ? null : ends[3],
      'come5': lockCodes.contains(day.code) ? null : starts[4],
      'leave5': lockCodes.contains(day.code) ? null : ends[4],
    };

    final uri = Uri.parse('https://api.windesign.at/workinghours.php');
    final res = await client.post(
      uri,
      headers: {'Content-Type': 'application/json'},
      body: jsonEncode(payload),
    );

    if (res.statusCode != 200) {
      throw Exception('booking/saveDay failed: ${res.statusCode} ${res.body}');
    }
    final map = jsonDecode(res.body) as Map<String, dynamic>;
    if (map['error'] == true) {
      throw Exception('booking/saveDay error: ${map['errmsg']}');
    }
  }

  /// Startwerte für einen Monat speichern (Upsert auf monthlybooking).
  /// `monthStart` = 1. des Monats.
  Future<void> saveMonthStart(
    DateTime monthStart, {
    required int starthours,
    required int startvacation,
    int overtime = 0,
    int correction = 0,
  }) async {
    final y = monthStart.year.toString().padLeft(4, '0');
    final m = monthStart.month.toString().padLeft(2, '0');
    final d = '01'; // normalize
    final uri = Uri.parse('https://api.windesign.at/workinghours.php');

    final payload = {
      'module': 'monthlybooking',
      'function': 'saveStart',
      'date': '$y-$m-$d',
      'starthours': starthours,
      'startvacation': startvacation,
      'overtime': overtime,
      'correction': correction,
    };

    final res = await client.post(
      uri,
      headers: {'Content-Type': 'application/json'},
      body: jsonEncode(payload),
    );

    if (res.statusCode != 200) {
      throw Exception('monthlybooking/saveStart failed: ${res.statusCode} ${res.body}');
    }
    final map = jsonDecode(res.body) as Map<String, dynamic>;
    if (map['error'] == true) {
      throw Exception('monthlybooking/saveStart error: ${map['errmsg']}');
    }
  }

}