import 'package:uuid/uuid.dart';

class Message {
  final String id;
  final String role; // 'user' or 'assistant'
  final String content;
  final DateTime timestamp;
  final bool isStreaming;
  final List<String>? attachments;

  Message({
    String? id,
    required this.role,
    required this.content,
    DateTime? timestamp,
    this.isStreaming = false,
    this.attachments,
  })  : id = id ?? const Uuid().v4(),
        timestamp = timestamp ?? DateTime.now();

  Message copyWith({
    String? id,
    String? role,
    String? content,
    DateTime? timestamp,
    bool? isStreaming,
    List<String>? attachments,
  }) {
    return Message(
      id: id ?? this.id,
      role: role ?? this.role,
      content: content ?? this.content,
      timestamp: timestamp ?? this.timestamp,
      isStreaming: isStreaming ?? this.isStreaming,
      attachments: attachments ?? this.attachments,
    );
  }

  factory Message.fromJson(Map<String, dynamic> json) {
    return Message(
      id: json['id'],
      role: json['role'],
      content: json['content'],
      timestamp: json['timestamp'] != null
          ? DateTime.parse(json['timestamp'])
          : DateTime.now(),
      attachments: json['attachments'] != null
          ? List<String>.from(json['attachments'])
          : null,
    );
  }

  Map<String, dynamic> toJson() {
    return {
      'id': id,
      'role': role,
      'content': content,
      'timestamp': timestamp.toIso8601String(),
      'attachments': attachments,
    };
  }

  bool get isUser => role == 'user';
  bool get isAssistant => role == 'assistant';
}