import 'package:flutter/foundation.dart';

/// Immutable application-level user identity representation.
/// Keeps Firebase types out of the presentation and telemetry layers.
@immutable
class AuthUser {
  final String uid;
  final String? email;
  final String? displayName;
  final String? photoUrl;
  final bool isAnonymous;
  final bool emailVerified;
  final String? providerId;
  final DateTime? createdAt;
  final DateTime? lastSignInTime;

  const AuthUser({
    required this.uid,
    this.email,
    this.displayName,
    this.photoUrl,
    this.isAnonymous = false,
    this.emailVerified = false,
    this.providerId,
    this.createdAt,
    this.lastSignInTime,
  });

  /// True if the user has an authenticated email or external identity
  bool get hasIdentifiedAccount => !isAnonymous && (email != null || displayName != null);

  /// Formatted display name fallback
  String get displayLabel {
    if (displayName != null && displayName!.isNotEmpty) return displayName!;
    if (email != null && email!.isNotEmpty) return email!;
    if (isAnonymous) return 'Anonymous Rider';
    return 'Rider ($uid)';
  }

  Map<String, dynamic> toJson() => {
        'uid': uid,
        'email': email,
        'displayName': displayName,
        'photoUrl': photoUrl,
        'isAnonymous': isAnonymous,
        'emailVerified': emailVerified,
        'providerId': providerId,
        'createdAt': createdAt?.toIso8601String(),
        'lastSignInTime': lastSignInTime?.toIso8601String(),
      };

  factory AuthUser.fromJson(Map<String, dynamic> json) => AuthUser(
        uid: json['uid'] as String? ?? '',
        email: json['email'] as String?,
        displayName: json['displayName'] as String?,
        photoUrl: json['photoUrl'] as String?,
        isAnonymous: json['isAnonymous'] as bool? ?? false,
        emailVerified: json['emailVerified'] as bool? ?? false,
        providerId: json['providerId'] as String?,
        createdAt: json['createdAt'] != null
            ? DateTime.tryParse(json['createdAt'] as String)
            : null,
        lastSignInTime: json['lastSignInTime'] != null
            ? DateTime.tryParse(json['lastSignInTime'] as String)
            : null,
      );

  AuthUser copyWith({
    String? uid,
    String? email,
    String? displayName,
    String? photoUrl,
    bool? isAnonymous,
    bool? emailVerified,
    String? providerId,
    DateTime? createdAt,
    DateTime? lastSignInTime,
  }) {
    return AuthUser(
      uid: uid ?? this.uid,
      email: email ?? this.email,
      displayName: displayName ?? this.displayName,
      photoUrl: photoUrl ?? this.photoUrl,
      isAnonymous: isAnonymous ?? this.isAnonymous,
      emailVerified: emailVerified ?? this.emailVerified,
      providerId: providerId ?? this.providerId,
      createdAt: createdAt ?? this.createdAt,
      lastSignInTime: lastSignInTime ?? this.lastSignInTime,
    );
  }

  @override
  bool operator ==(Object other) =>
      identical(this, other) ||
      other is AuthUser &&
          runtimeType == other.runtimeType &&
          uid == other.uid &&
          email == other.email &&
          displayName == other.displayName &&
          isAnonymous == other.isAnonymous &&
          emailVerified == other.emailVerified &&
          providerId == other.providerId;

  @override
  int get hashCode =>
      uid.hashCode ^
      email.hashCode ^
      displayName.hashCode ^
      isAnonymous.hashCode ^
      emailVerified.hashCode ^
      providerId.hashCode;

  @override
  String toString() =>
      'AuthUser(uid: $uid, email: $email, name: $displayName, anon: $isAnonymous, provider: $providerId)';
}