class VideoItem {
  const VideoItem({
    required this.id,
    required this.title,
    required this.author,
    required this.thumbnailUrl,
    this.duration,
    this.channelId,
    this.viewCount,
    this.likeCount,
    this.commentCount,
    this.description = '',
    this.uploadDate,
  });

  final String id;
  final String title;
  final String author;
  final String thumbnailUrl;
  final Duration? duration;

  /// YouTube channel ID when it is known.
  ///
  /// Old history/favorites saved before step 18.3 simply have null here.
  /// The channel screen can resolve it lazily from the video ID.
  final String? channelId;

  /// Public YouTube view count at the time the metadata was fetched.
  final int? viewCount;

  /// Public likes for this video when YouTube exposes the statistic.
  final int? likeCount;

  /// Public comments for this video when YouTube exposes the statistic.
  final int? commentCount;

  /// Public YouTube video description.
  final String description;

  /// YouTube upload date when available.
  final DateTime? uploadDate;

  String get durationLabel {
    final value = duration;
    if (value == null) {
      return '';
    }

    final hours = value.inHours;
    final minutes = value.inMinutes.remainder(60);
    final seconds = value.inSeconds.remainder(60);

    if (hours > 0) {
      return '$hours:${minutes.toString().padLeft(2, '0')}:'
          '${seconds.toString().padLeft(2, '0')}';
    }

    return '$minutes:${seconds.toString().padLeft(2, '0')}';
  }

  Map<String, dynamic> toJson() {
    return {
      'id': id,
      'title': title,
      'author': author,
      'thumbnailUrl': thumbnailUrl,
      'durationSeconds': duration?.inSeconds,
      if (channelId != null) 'channelId': channelId,
      if (viewCount != null) 'viewCount': viewCount,
      if (likeCount != null) 'likeCount': likeCount,
      if (commentCount != null) 'commentCount': commentCount,
      if (description.isNotEmpty) 'description': description,
      if (uploadDate != null)
        'uploadDate': uploadDate!.toIso8601String(),
    };
  }

  factory VideoItem.fromJson(Map<String, dynamic> json) {
    final durationSeconds = json['durationSeconds'];
    final rawViewCount = json['viewCount'];
    final rawLikeCount = json['likeCount'];
    final rawCommentCount = json['commentCount'];
    final rawUploadDate = json['uploadDate'];

    return VideoItem(
      id: json['id'] as String,
      title: json['title'] as String,
      author: json['author'] as String,
      thumbnailUrl: json['thumbnailUrl'] as String,
      duration: durationSeconds is num
          ? Duration(seconds: durationSeconds.toInt())
          : null,
      channelId: json['channelId'] is String
          ? json['channelId'] as String
          : null,
      viewCount: rawViewCount is num
          ? rawViewCount.toInt()
          : null,
      likeCount: rawLikeCount is num
          ? rawLikeCount.toInt()
          : null,
      commentCount: rawCommentCount is num
          ? rawCommentCount.toInt()
          : null,
      description: json['description'] is String
          ? json['description'] as String
          : '',
      uploadDate: rawUploadDate is String
          ? DateTime.tryParse(rawUploadDate)
          : null,
    );
  }
}