BlockSeasons/lib/game/models/season.dart

import 'stage.dart';

class SeasonTheme {
  const SeasonTheme({required this.tileSet, required this.background});

  factory SeasonTheme.fromJson(Map<String, dynamic> json) => SeasonTheme(
        tileSet: json['tileSet'] as String,
        background: json['background'] as String,
      );

  final String tileSet;
  final String background;

  Map<String, dynamic> toJson() =>
      {'tileSet': tileSet, 'background': background};
}

/// A season's full content: metadata, theme, and its stages. The unit of
/// remote (or bundled) delivery.
class SeasonPack {
  const SeasonPack({
    required this.schemaVersion,
    required this.seasonId,
    required this.version,
    required this.title,
    required this.theme,
    required this.stages,
  });

  /// Bump when the pack format changes incompatibly; older app builds skip
  /// packs with a newer schema instead of crashing.
  static const int supportedSchema = 1;

  factory SeasonPack.fromJson(Map<String, dynamic> json) {
    final schema = json['schemaVersion'] as int;
    if (schema > supportedSchema) {
      throw FormatException('Unsupported pack schema: $schema');
    }
    return SeasonPack(
      schemaVersion: schema,
      seasonId: json['seasonId'] as String,
      version: json['version'] as int,
      title: (json['title'] as Map<String, dynamic>)
          .map((k, v) => MapEntry(k, v as String)),
      theme: SeasonTheme.fromJson(json['theme'] as Map<String, dynamic>),
      stages: [
        for (final stage in json['stages'] as List)
          StageConfig.fromJson(stage as Map<String, dynamic>),
      ],
    );
  }

  final int schemaVersion;
  final String seasonId;
  final int version;
  final Map<String, String> title;
  final SeasonTheme theme;
  final List<StageConfig> stages;

  String titleFor(String languageCode) =>
      title[languageCode] ?? title['en'] ?? seasonId;

  Map<String, dynamic> toJson() => {
        'schemaVersion': schemaVersion,
        'seasonId': seasonId,
        'version': version,
        'title': title,
        'theme': theme.toJson(),
        'stages': [for (final stage in stages) stage.toJson()],
      };
}