nj/app/lib/features/discover/models/discover_models.dart

// 发现页数据模型 — 手写不可变类（避免 build_runner 依赖）

/// 发现页聚合响应 — 一次 API 返回全部板块数据
class DiscoverData {
  final InspirationItem? dailyInspiration;
  final List<TagCount> hotTopics;
  final List<DiscoverTemplateItem> featuredTemplates;
  final List<ExpertDiaryItem> expertDiaries;

  const DiscoverData({
    this.dailyInspiration,
    this.hotTopics = const [],
    this.featuredTemplates = const [],
    this.expertDiaries = const [],
  });

  factory DiscoverData.fromJson(Map<String, dynamic> json) => DiscoverData(
        dailyInspiration: json['daily_inspiration'] != null
            ? InspirationItem.fromJson(
                json['daily_inspiration'] as Map<String, dynamic>)
            : null,
        hotTopics: (json['hot_topics'] as List? ?? [])
            .map((e) => TagCount.fromJson(e as Map<String, dynamic>))
            .toList(),
        featuredTemplates: (json['featured_templates'] as List? ?? [])
            .map(
                (e) => DiscoverTemplateItem.fromJson(e as Map<String, dynamic>))
            .toList(),
        expertDiaries: (json['expert_diaries'] as List? ?? [])
            .map((e) => ExpertDiaryItem.fromJson(e as Map<String, dynamic>))
            .toList(),
      );

  /// 心情 → emoji 映射
  static String moodToEmoji(String mood) => switch (mood) {
        'happy' => '😊',
        'calm' => '😌',
        'sad' => '😢',
        'angry' => '😤',
        'thinking' => '🤔',
        _ => '📝',
      };
}

/// 每日推荐条目
class InspirationItem {
  final String journalId;
  final String title;
  final String authorName;
  final String mood;
  final DateTime date;

  const InspirationItem({
    required this.journalId,
    required this.title,
    required this.authorName,
    required this.mood,
    required this.date,
  });

  factory InspirationItem.fromJson(Map<String, dynamic> json) =>
      InspirationItem(
        journalId: json['journal_id'] as String,
        title: json['title'] as String,
        authorName: json['author_name'] as String,
        mood: json['mood'] as String,
        date: DateTime.parse(json['date'] as String),
      );
}

/// 热门话题
class TagCount {
  final String tag;
  final int count;

  const TagCount({required this.tag, required this.count});

  factory TagCount.fromJson(Map<String, dynamic> json) => TagCount(
        tag: json['tag'] as String,
        count: json['count'] as int,
      );
}

/// 精选模板条目（轻量版，不含 layout_data）
class DiscoverTemplateItem {
  final String id;
  final String name;
  final String? previewUrl;
  final String? category;
  final bool isFree;

  const DiscoverTemplateItem({
    required this.id,
    required this.name,
    this.previewUrl,
    this.category,
    this.isFree = true,
  });

  factory DiscoverTemplateItem.fromJson(Map<String, dynamic> json) =>
      DiscoverTemplateItem(
        id: json['id'] as String,
        name: json['name'] as String,
        previewUrl: json['preview_url'] as String?,
        category: json['category'] as String?,
        isFree: json['is_free'] as bool? ?? true,
      );

  /// 分类 → emoji 映射
  String get emoji => switch (category) {
        '日常' => '📖',
        '旅行' => '✈️',
        '校园' => '🎓',
        '节日' => '🎄',
        '创意' => '✨',
        '心情' => '🌿',
        _ => '📝',
      };

  /// 使用人数展示文本
  String get usageText => isFree ? '免费模板' : '精品模板';
}

/// 达人日记条目
class ExpertDiaryItem {
  final String journalId;
  final String title;
  final String authorId;
  final String authorName;
  final String authorEmoji;
  final String contentPreview;
  final int likeCount;
  final DateTime createdAt;

  const ExpertDiaryItem({
    required this.journalId,
    required this.title,
    required this.authorId,
    required this.authorName,
    required this.authorEmoji,
    required this.contentPreview,
    required this.likeCount,
    required this.createdAt,
  });

  factory ExpertDiaryItem.fromJson(Map<String, dynamic> json) =>
      ExpertDiaryItem(
        journalId: json['journal_id'] as String,
        title: json['title'] as String,
        authorId: json['author_id'] as String,
        authorName: json['author_name'] as String,
        authorEmoji: json['author_emoji'] as String,
        contentPreview: json['content_preview'] as String? ?? '',
        likeCount: json['like_count'] as int? ?? 0,
        createdAt: DateTime.parse(json['created_at'] as String),
      );

  /// 点赞数展示文本
  String get likeText => '$likeCount 赞';
}