import 'package:ac_web/Api/JsonReader.dart';

/// Dart counterpart of the backend `AgentTaskDto`.
///
/// A task is one piece of work an agent is currently busy with. While it runs
/// the agent appends short lines to [statusUpdates], so the list doubles as
/// the history of the task.
class AgentTaskDto {
  const AgentTaskDto({
    required this.title,
    this.startTime,
    this.statusUpdates = const <String>[],
  });

  final String title;

  /// Moment the agent picked the task up, if the api reports it.
  final DateTime? startTime;

  /// Every status line the agent reported so far, oldest first.
  final List<String> statusUpdates;

  bool get hasStatusUpdates => statusUpdates.isNotEmpty;

  /// The most recent status line, or null while the agent did not report one.
  String? get latestStatus => statusUpdates.isEmpty ? null : statusUpdates.last;

  factory AgentTaskDto.fromJson(Map<String, dynamic> json) {
    return AgentTaskDto(
      // Older builds of the api called the property "Name".
      title: JsonReader.optionalString(json, 'Title') ??
          JsonReader.optionalString(json, 'Name') ??
          '',
      startTime: JsonReader.optionalDateTime(json, 'StartTime'),
      statusUpdates: JsonReader.stringList(json, 'StatusUpdates'),
    );
  }

  Map<String, dynamic> toJson() {
    return <String, dynamic>{
      'Title': title,
      if (startTime != null) 'StartTime': startTime!.toIso8601String(),
      'StatusUpdates': statusUpdates,
    };
  }

  @override
  String toString() => 'AgentTaskDto(title: $title, updates: ${statusUpdates.length})';
}