DateTime? _parseDateTime(dynamic value) {
  if (value == null) return null;
  final s = value.toString().trim();
  if (s.isEmpty) return null;
  try {
    return DateTime.parse(s);
  } catch (_) {
    return null;
  }
}

class User {
  final String id;
  final String mobileNumber;
  final String fullName;
  final String role; // 'manager' or 'member'
  final String? createdBy; // Manager who created this account
  final bool isActive;
  final String? email;
  final String? address;
  final String? emergencyContact;
  final DateTime createdAt;
  final DateTime updatedAt;

  User({
    required this.id,
    required this.mobileNumber,
    required this.fullName,
    required this.role,
    this.createdBy,
    required this.isActive,
    this.email,
    this.address,
    this.emergencyContact,
    required this.createdAt,
    required this.updatedAt,
  });

  factory User.fromJson(Map<String, dynamic> json) {
    return User(
      id: json['id'] ?? '',
      mobileNumber: json['mobile_number'] ?? '',
      fullName: json['full_name'] ?? '',
      role: json['role'] ?? 'member',
      createdBy: json['created_by'],
      isActive: json['is_active'] ?? true,
      email: json['email'],
      address: json['address'],
      emergencyContact: json['emergency_contact'],
      createdAt: _parseDateTime(json['created_at']) ?? DateTime.now(),
      updatedAt: _parseDateTime(json['updated_at']) ?? DateTime.now(),
    );
  }

  Map<String, dynamic> toJson() {
    return {
      'id': id,
      'mobile_number': mobileNumber,
      'full_name': fullName,
      'role': role,
      'created_by': createdBy,
      'is_active': isActive,
      if (email != null) 'email': email,
      if (address != null) 'address': address,
      if (emergencyContact != null) 'emergency_contact': emergencyContact,
      'created_at': createdAt.toIso8601String(),
      'updated_at': updatedAt.toIso8601String(),
    };
  }

  User copyWith({
    String? id,
    String? mobileNumber,
    String? fullName,
    String? role,
    String? createdBy,
    bool? isActive,
    String? email,
    String? address,
    String? emergencyContact,
    DateTime? createdAt,
    DateTime? updatedAt,
  }) {
    return User(
      id: id ?? this.id,
      mobileNumber: mobileNumber ?? this.mobileNumber,
      fullName: fullName ?? this.fullName,
      role: role ?? this.role,
      createdBy: createdBy ?? this.createdBy,
      isActive: isActive ?? this.isActive,
      email: email ?? this.email,
      address: address ?? this.address,
      emergencyContact: emergencyContact ?? this.emergencyContact,
      createdAt: createdAt ?? this.createdAt,
      updatedAt: updatedAt ?? this.updatedAt,
    );
  }
}