typedef JsonMap = Map<String, dynamic>;

String asString(Object? value, [String fallback = '']) =>
    value == null ? fallback : value.toString();

int asInt(Object? value, [int fallback = 0]) {
  if (value is int) return value;
  if (value is num) return value.round();
  return int.tryParse(asString(value)) ?? fallback;
}

bool asBool(Object? value) => value == true;

List<String> asStringList(Object? value) {
  if (value is List) return value.map((item) => item.toString()).toList();
  return const [];
}

JsonMap asMap(Object? value) {
  if (value is Map<String, dynamic>) return value;
  if (value is Map) {
    return value.map((key, val) => MapEntry(key.toString(), val));
  }
  return const {};
}

List<JsonMap> asMapList(Object? value) {
  if (value is List) {
    return value.map(asMap).where((item) => item.isNotEmpty).toList();
  }
  return const [];
}

String formatDate(String? iso) {
  if (iso == null || iso.isEmpty) return '';
  final parsed = DateTime.tryParse(iso);
  if (parsed == null) return iso;
  return '${parsed.year}年${parsed.month}月${parsed.day}日';
}

String formatDuration(int seconds) {
  final safe = seconds < 0 ? 0 : seconds;
  final minutes = safe ~/ 60;
  final secs = safe % 60;
  return '$minutes:${secs.toString().padLeft(2, '0')}';
}

class Institution {
  const Institution({
    required this.id,
    required this.nameCn,
    this.nameEn = '',
    this.logoUrl = '',
    this.institutionType = '',
    this.sourceTier = '',
    this.websiteUrl = '',
    this.coveredTopics = const [],
    this.reportCount = 0,
    this.latestReportAt,
    this.credibilityNote = '',
    this.introCn = '',
    this.recentReports = const [],
  });

  final String id;
  final String nameCn;
  final String nameEn;
  final String logoUrl;
  final String institutionType;
  final String sourceTier;
  final String websiteUrl;
  final List<String> coveredTopics;
  final int reportCount;
  final String? latestReportAt;
  final String credibilityNote;
  final String introCn;
  final List<ReportCardModel> recentReports;

  factory Institution.fromJson(JsonMap json) {
    return Institution(
      id: asString(json['institution_id']),
      nameCn: asString(json['name_cn']),
      nameEn: asString(json['name_en']),
      logoUrl: asString(json['logo_url']),
      institutionType: asString(json['institution_type']),
      sourceTier: asString(json['source_tier']),
      websiteUrl: asString(json['website_url']),
      coveredTopics: asStringList(json['covered_topics']),
      reportCount: asInt(json['report_count']),
      latestReportAt: json['latest_report_at']?.toString(),
      credibilityNote: asString(json['credibility_note']),
      introCn: asString(json['intro_cn']),
      recentReports: asMapList(
        json['recent_reports'],
      ).map(ReportCardModel.fromJson).toList(),
    );
  }
}

class ReportCardModel {
  const ReportCardModel({
    required this.id,
    required this.titleCn,
    required this.institution,
    this.subtitleCn = '',
    this.oneLiner = '',
    this.topics = const [],
    this.releasedAt,
    this.hasAudio = false,
    this.interpretationLabel = '研报解读',
    this.sourceTier = '',
    this.cacheVersion = '',
  });

  final String id;
  final String titleCn;
  final String subtitleCn;
  final String oneLiner;
  final Institution institution;
  final List<String> topics;
  final String? releasedAt;
  final bool hasAudio;
  final String interpretationLabel;
  final String sourceTier;
  final String cacheVersion;

  factory ReportCardModel.fromJson(JsonMap json) {
    final institution = Institution.fromJson(asMap(json['institution']));
    return ReportCardModel(
      id: asString(json['report_id']),
      titleCn: asString(json['title_cn']),
      subtitleCn: asString(json['subtitle_cn']),
      oneLiner: asString(json['one_liner']),
      institution: institution,
      topics: asStringList(json['topics']),
      releasedAt: json['released_at']?.toString(),
      hasAudio: asBool(json['has_audio']),
      interpretationLabel: asString(json['interpretation_label'], '研报解读'),
      sourceTier: asString(json['source_tier']),
      cacheVersion: asString(json['cache_version']),
    );
  }
}

class AudioItem {
  const AudioItem({
    required this.audioId,
    required this.reportId,
    required this.titleCn,
    required this.reportTitleCn,
    required this.durationSec,
    required this.institution,
    this.releasedAt,
    this.cacheVersion = '',
  });

  final String audioId;
  final String reportId;
  final String titleCn;
  final String reportTitleCn;
  final int durationSec;
  final Institution institution;
  final String? releasedAt;
  final String cacheVersion;

  factory AudioItem.fromJson(JsonMap json) {
    return AudioItem(
      audioId: asString(json['audio_id']),
      reportId: asString(json['report_id']),
      titleCn: asString(json['title_cn']),
      reportTitleCn: asString(
        json['report_title_cn'],
        asString(json['title_cn']),
      ),
      durationSec: asInt(json['duration_sec']),
      institution: Institution.fromJson(asMap(json['institution'])),
      releasedAt: json['released_at']?.toString(),
      cacheVersion: asString(json['cache_version']),
    );
  }
}

class DisplayModule {
  const DisplayModule({
    required this.id,
    required this.type,
    required this.titleCn,
    required this.renderMode,
    this.layer = '',
    this.hasDetailPage = false,
    this.sortOrder = 0,
    this.content = const {},
    this.preview = const {},
    this.contentRef = '',
    this.contentEtag = '',
  });

  final String id;
  final String type;
  final String titleCn;
  final String layer;
  final String renderMode;
  final bool hasDetailPage;
  final int sortOrder;
  final JsonMap content;
  final JsonMap preview;
  final String contentRef;
  final String contentEtag;

  factory DisplayModule.fromJson(JsonMap json) {
    return DisplayModule(
      id: asString(json['module_id']),
      type: asString(json['type']),
      titleCn: asString(json['title_cn'], asString(json['type'])),
      layer: asString(json['layer']),
      renderMode: asString(json['render_mode'], 'inline'),
      hasDetailPage: asBool(json['has_detail_page']),
      sortOrder: asInt(json['sort_order']),
      content: asMap(json['content']),
      preview: asMap(json['preview']),
      contentRef: asString(json['content_ref']),
      contentEtag: asString(json['content_etag']),
    );
  }
}

class ReportDetail {
  const ReportDetail({
    required this.id,
    required this.titleCn,
    required this.institution,
    this.subtitleCn = '',
    this.originalTitle = '',
    this.oneLiner = '',
    this.source = const {},
    this.topics = const [],
    this.hasAudio = false,
    this.interpretationLabel = '研报解读',
    this.riskDisclaimer = '',
    this.releasedAt,
    this.cacheVersion = '',
    this.modules = const [],
  });

  final String id;
  final String titleCn;
  final String subtitleCn;
  final String originalTitle;
  final String oneLiner;
  final Institution institution;
  final JsonMap source;
  final List<String> topics;
  final bool hasAudio;
  final String interpretationLabel;
  final String riskDisclaimer;
  final String? releasedAt;
  final String cacheVersion;
  final List<DisplayModule> modules;

  factory ReportDetail.fromJson(JsonMap json) {
    return ReportDetail(
      id: asString(json['report_id']),
      titleCn: asString(json['title_cn']),
      subtitleCn: asString(json['subtitle_cn']),
      originalTitle: asString(json['original_title']),
      oneLiner: asString(json['one_liner']),
      institution: Institution.fromJson(asMap(json['institution'])),
      source: asMap(json['source']),
      topics: asStringList(json['topics']),
      hasAudio: asBool(json['has_audio']),
      interpretationLabel: asString(json['interpretation_label'], '研报解读'),
      riskDisclaimer: asString(json['risk_disclaimer']),
      releasedAt: json['released_at']?.toString(),
      cacheVersion: asString(json['cache_version']),
      modules: asMapList(json['modules']).map(DisplayModule.fromJson).toList(),
    );
  }

  ReportCardModel asCard() {
    return ReportCardModel(
      id: id,
      titleCn: titleCn,
      subtitleCn: subtitleCn,
      oneLiner: oneLiner,
      institution: institution,
      topics: topics,
      releasedAt: releasedAt,
      hasAudio: hasAudio,
      interpretationLabel: interpretationLabel,
      sourceTier: asString(source['source_tier']),
      cacheVersion: cacheVersion,
    );
  }
}

class ModuleDetail {
  const ModuleDetail({
    required this.id,
    required this.type,
    required this.titleCn,
    this.content = const {},
    this.contentEtag = '',
    this.cacheVersion = '',
  });

  final String id;
  final String type;
  final String titleCn;
  final JsonMap content;
  final String contentEtag;
  final String cacheVersion;

  factory ModuleDetail.fromJson(JsonMap json) {
    return ModuleDetail(
      id: asString(json['module_id']),
      type: asString(json['type']),
      titleCn: asString(json['title_cn'], asString(json['type'])),
      content: asMap(json['content']),
      contentEtag: asString(json['content_etag']),
      cacheVersion: asString(json['cache_version']),
    );
  }
}