import 'dart:convert';
import 'package:http/http.dart' as http;
import 'settings.dart';

class ApiException implements Exception {
  final String message;
  final int? status;
  ApiException(this.message, [this.status]);
  @override
  String toString() => message;
}

class Profile {
  final String gid, fullName, role;
  final String? employeeCode, departmentName, designationTitle, reportingManagerName;
  final bool isManager;
  Profile.fromJson(Map<String, dynamic> j)
      : gid = j['gid'] ?? '',
        fullName = j['fullName'] ?? '',
        role = j['role'] ?? 'EMPLOYEE',
        employeeCode = j['employeeCode'],
        departmentName = j['departmentName'],
        designationTitle = j['designationTitle'],
        reportingManagerName = j['reportingManagerName'],
        isManager = j['isManager'] == true;
}

class Today {
  final String? status, checkIn, checkOut, date;
  final num? hours, otHours;
  final int? lateMinutes;
  final bool checkedIn;
  Today.fromJson(Map<String, dynamic> j)
      : status = j['status'],
        checkIn = j['checkIn'],
        checkOut = j['checkOut'],
        date = j['date'],
        hours = j['hours'],
        otHours = j['otHours'],
        lateMinutes = j['lateMinutes'],
        checkedIn = j['checkedIn'] == true;
}

class LeaveBalance {
  final String leaveTypeGid, leaveTypeName;
  final bool paid;
  final num allocated, used, available;
  LeaveBalance.fromJson(Map<String, dynamic> j)
      : leaveTypeGid = j['leaveTypeGid'] ?? '',
        leaveTypeName = j['leaveTypeName'] ?? '',
        paid = j['paid'] == true,
        allocated = j['allocated'] ?? 0,
        used = j['used'] ?? 0,
        available = j['available'] ?? 0;
}

class LeaveType {
  final String gid, name;
  final bool paid;
  LeaveType.fromJson(Map<String, dynamic> j)
      : gid = j['gid'] ?? '',
        name = j['name'] ?? '',
        paid = j['paid'] == true;
}

class LeaveRequest {
  final String gid, status;
  final String? leaveTypeName, fromDate, toDate, reason, employeeName;
  final num? days;
  LeaveRequest.fromJson(Map<String, dynamic> j)
      : gid = j['gid'] ?? '',
        status = j['status'] ?? '',
        leaveTypeName = j['leaveTypeName'],
        fromDate = j['fromDate'],
        toDate = j['toDate'],
        reason = j['reason'],
        employeeName = j['employeeName'],
        days = j['days'];
}

class Payslip {
  final String gid, periodMonth, status;
  final num gross, totalDeductions, netPay;
  Payslip.fromJson(Map<String, dynamic> j)
      : gid = j['gid'] ?? '',
        periodMonth = j['periodMonth'] ?? '',
        status = j['status'] ?? '',
        gross = j['gross'] ?? 0,
        totalDeductions = j['totalDeductions'] ?? 0,
        netPay = j['netPay'] ?? 0;
}

class TeamMember {
  final String employeeGid, employeeName, status;
  final String? employeeCode, checkIn, checkOut;
  final num? hours;
  final bool checkedIn;
  TeamMember.fromJson(Map<String, dynamic> j)
      : employeeGid = j['employeeGid'] ?? '',
        employeeName = j['employeeName'] ?? '',
        status = j['status'] ?? '—',
        employeeCode = j['employeeCode'],
        checkIn = j['checkIn'],
        checkOut = j['checkOut'],
        hours = j['hours'],
        checkedIn = j['checkedIn'] == true;
}

class ApiService {
  final Settings settings;
  ApiService(this.settings);

  Uri _uri(String p, [Map<String, String>? q]) =>
      Uri.parse('${settings.baseUrl}$p').replace(queryParameters: q);

  Map<String, String> get _h => {
        'Content-Type': 'application/json',
        if ((settings.token ?? '').isNotEmpty) 'Authorization': 'Bearer ${settings.token}',
      };

  // ---- auth ----
  Future<Profile> login(String identifier, String pin) async {
    http.Response res;
    try {
      res = await http
          .post(_uri('/api/v1/employee/auth/login'),
              headers: {'Content-Type': 'application/json'},
              body: jsonEncode({'identifier': identifier.trim(), 'pin': pin}))
          .timeout(const Duration(seconds: 20));
    } catch (_) {
      throw ApiException('Cannot reach server. Check the URL and connection.');
    }
    final body = _json(res);
    if (res.statusCode != 200 || body is! Map) {
      throw ApiException(_msg(body) ?? 'Invalid email or PIN', res.statusCode);
    }
    final p = Profile.fromJson(body['profile'] as Map<String, dynamic>);
    await settings.saveSession(token: body['accessToken'] as String, name: p.fullName, role: p.role);
    return p;
  }

  // ---- me ----
  Future<Profile> profile() async => Profile.fromJson(await _get('/api/v1/me/profile'));
  Future<Today> today() async => Today.fromJson(await _get('/api/v1/me/attendance/today'));

  Future<void> checkIn({double? lat, double? lng, String? selfie}) =>
      _post('/api/v1/me/attendance/check-in', _geo(lat, lng, selfie));
  Future<void> checkOut({double? lat, double? lng, String? selfie}) =>
      _post('/api/v1/me/attendance/check-out', _geo(lat, lng, selfie));
  Map<String, dynamic> _geo(double? lat, double? lng, String? selfie) => {
        if (lat != null) 'lat': lat,
        if (lng != null) 'lng': lng,
        if (selfie != null) 'selfie': selfie,
      };

  Future<List<LeaveType>> leaveTypes() async =>
      (await _get('/api/v1/me/leave/types') as List).map((e) => LeaveType.fromJson(e)).toList();
  Future<List<LeaveBalance>> leaveBalances() async =>
      (await _get('/api/v1/me/leave/balances') as List).map((e) => LeaveBalance.fromJson(e)).toList();
  Future<List<LeaveRequest>> myLeave() async =>
      (await _get('/api/v1/me/leave/requests') as List).map((e) => LeaveRequest.fromJson(e)).toList();
  Future<void> applyLeave(String typeGid, String from, String to, String reason) =>
      _post('/api/v1/me/leave/requests', {'leaveTypeGid': typeGid, 'fromDate': from, 'toDate': to, 'reason': reason});

  Future<List<Payslip>> payslips() async =>
      (await _get('/api/v1/me/payslips') as List).map((e) => Payslip.fromJson(e)).toList();

  Future<List<TeamMember>> team() async =>
      (await _get('/api/v1/me/team') as List).map((e) => TeamMember.fromJson(e)).toList();
  Future<List<LeaveRequest>> teamLeave() async =>
      (await _get('/api/v1/me/team/leave') as List).map((e) => LeaveRequest.fromJson(e)).toList();
  Future<void> approve(String gid) => _post('/api/v1/me/team/leave/$gid/approve', {});
  Future<void> reject(String gid) => _post('/api/v1/me/team/leave/$gid/reject', {});

  // ---- helpers ----
  Future<dynamic> _get(String p, [Map<String, String>? q]) async {
    http.Response r;
    try {
      r = await http.get(_uri(p, q), headers: _h).timeout(const Duration(seconds: 20));
    } catch (_) {
      throw ApiException('Network error');
    }
    return _handle(r);
  }

  Future<dynamic> _post(String p, Map<String, dynamic> body) async {
    http.Response r;
    try {
      r = await http.post(_uri(p), headers: _h, body: jsonEncode(body)).timeout(const Duration(seconds: 20));
    } catch (_) {
      throw ApiException('Network error');
    }
    return _handle(r);
  }

  dynamic _handle(http.Response r) {
    if (r.statusCode == 401) throw ApiException('Session expired. Please sign in again.', 401);
    if (r.statusCode == 204 || r.body.isEmpty) return null;
    final body = _json(r);
    if (r.statusCode >= 400) throw ApiException(_msg(body) ?? 'Request failed (${r.statusCode})', r.statusCode);
    if (body is Map && body.containsKey('data') && body.containsKey('success')) return body['data'];
    return body;
  }

  dynamic _json(http.Response r) {
    try {
      return jsonDecode(r.body);
    } catch (_) {
      return null;
    }
  }

  String? _msg(dynamic b) => (b is Map && b['message'] is String) ? b['message'] as String : null;
}