/// Domain Entity: News Article
///
/// Pure business entity representing a news article or blog post.
/// This entity is framework-independent and contains only business logic.
library;

/// News Article Entity
///
/// Represents a news article/blog post in the app.
/// Used for displaying news, tips, project showcases, and professional content.
class NewsArticle {
  /// Unique article ID
  final String id;

  /// Article title
  final String title;

  /// Article excerpt/summary
  final String excerpt;

  /// Full article content (optional, may load separately)
  final String? content;

  /// Featured image URL
  final String imageUrl;

  /// Article category
  final NewsCategory category;

  /// Publication date
  final DateTime publishedDate;

  /// View count
  final int viewCount;

  /// Estimated reading time in minutes
  final int readingTimeMinutes;

  /// Whether this is a featured article
  final bool isFeatured;

  /// Author name (optional)
  final String? authorName;

  /// Author avatar URL (optional)
  final String? authorAvatar;

  /// Tags/keywords for the article
  final List<String> tags;

  /// Like count
  final int likeCount;

  /// Comment count
  final int commentCount;

  /// Share count
  final int shareCount;

  /// Constructor
  const NewsArticle({
    required this.id,
    required this.title,
    required this.excerpt,
    this.content,
    required this.imageUrl,
    required this.category,
    required this.publishedDate,
    required this.viewCount,
    required this.readingTimeMinutes,
    this.isFeatured = false,
    this.authorName,
    this.authorAvatar,
    this.tags = const [],
    this.likeCount = 0,
    this.commentCount = 0,
    this.shareCount = 0,
  });

  /// Get formatted publication date (dd/MM/yyyy)
  String get formattedDate {
    return '${publishedDate.day.toString().padLeft(2, '0')}/'
        '${publishedDate.month.toString().padLeft(2, '0')}/'
        '${publishedDate.year}';
  }

  /// Get formatted view count (e.g., "2.3K")
  String get formattedViewCount {
    if (viewCount >= 1000) {
      return '${(viewCount / 1000).toStringAsFixed(1)}K';
    }
    return viewCount.toString();
  }

  /// Get reading time display text
  String get readingTimeText => '$readingTimeMinutes phút đọc';

  /// Copy with method for immutability
  NewsArticle copyWith({
    String? id,
    String? title,
    String? excerpt,
    String? content,
    String? imageUrl,
    NewsCategory? category,
    DateTime? publishedDate,
    int? viewCount,
    int? readingTimeMinutes,
    bool? isFeatured,
    String? authorName,
    String? authorAvatar,
    List<String>? tags,
    int? likeCount,
    int? commentCount,
    int? shareCount,
  }) {
    return NewsArticle(
      id: id ?? this.id,
      title: title ?? this.title,
      excerpt: excerpt ?? this.excerpt,
      content: content ?? this.content,
      imageUrl: imageUrl ?? this.imageUrl,
      category: category ?? this.category,
      publishedDate: publishedDate ?? this.publishedDate,
      viewCount: viewCount ?? this.viewCount,
      readingTimeMinutes: readingTimeMinutes ?? this.readingTimeMinutes,
      isFeatured: isFeatured ?? this.isFeatured,
      authorName: authorName ?? this.authorName,
      authorAvatar: authorAvatar ?? this.authorAvatar,
      tags: tags ?? this.tags,
      likeCount: likeCount ?? this.likeCount,
      commentCount: commentCount ?? this.commentCount,
      shareCount: shareCount ?? this.shareCount,
    );
  }

  /// Equality operator
  @override
  bool operator ==(Object other) {
    if (identical(this, other)) return true;

    return other is NewsArticle && other.id == id;
  }

  /// Hash code
  @override
  int get hashCode {
    return id.hashCode;
  }

  /// String representation
  @override
  String toString() {
    return 'NewsArticle(id: $id, title: $title, category: $category, '
        'publishedDate: $publishedDate, isFeatured: $isFeatured)';
  }
}

/// News Category enum
enum NewsCategory {
  /// General news
  news,

  /// Professional/technical content
  professional,

  /// Project showcases
  projects,

  /// Events
  events,

  /// Promotions
  promotions,
}

/// Extension for News Category display
extension NewsCategoryX on NewsCategory {
  String get displayName {
    switch (this) {
      case NewsCategory.news:
        return 'Tin tức';
      case NewsCategory.professional:
        return 'Chuyên môn';
      case NewsCategory.projects:
        return 'Dự án';
      case NewsCategory.events:
        return 'Sự kiện';
      case NewsCategory.promotions:
        return 'Khuyến mãi';
    }
  }

  String get filterName {
    switch (this) {
      case NewsCategory.news:
        return 'news';
      case NewsCategory.professional:
        return 'professional';
      case NewsCategory.projects:
        return 'projects';
      case NewsCategory.events:
        return 'events';
      case NewsCategory.promotions:
        return 'promotions';
    }
  }
}