feat: add package source compatibility controls

lib/runtime/packages/game_package_repository.dart

@@ -38,6 +38,35 @@ class AssetGamePackageRepository implements GamePackageRepository {
   }
 }
 
+class FileGamePackageRepository implements GamePackageRepository {
+  const FileGamePackageRepository({
+    required this.baseDirectory,
+    this.runtimeOptions = const RuntimeOptions(),
+  });
+
+  final String baseDirectory;
+  final RuntimeOptions runtimeOptions;
+
+  @override
+  Future<GamePackage> load(String gameId) async {
+    final root = Directory(p.join(baseDirectory, gameId));
+    final manifestFile = File(p.join(root.path, 'manifest.json'));
+    if (!manifestFile.existsSync()) {
+      throw FileSystemException(
+        'Game package manifest not found',
+        manifestFile.path,
+      );
+    }
+    return GamePackage.file(
+      rootPath: root.path,
+      manifest: GamePackageManifest.fromJsonString(
+        await manifestFile.readAsString(),
+      ),
+      runtimeLuaRoot: runtimeOptions.runtimeLuaRoot,
+    );
+  }
+}
+
 class RemoteGamePackageRepository implements GamePackageRepository {
   RemoteGamePackageRepository({
     required this.baseUri,
@@ -103,6 +132,10 @@ class RemoteGamePackageRepository implements GamePackageRepository {
     if (remoteManifest.gameId != gameId) {
       throw const FormatException('Remote manifest gameId mismatch');
     }
+    remoteManifest.compatibility.verify(
+      runtimeApiVersion: runtimeApiVersion,
+      runtimeOptions: runtimeOptions,
+    );
 
     final packageRoot = await _downloadAndExtract(
       client,
@@ -130,7 +163,7 @@ class RemoteGamePackageRepository implements GamePackageRepository {
     http.Client client,
     String gameId,
   ) async {
-    final uri = baseUri.resolve('$gameId/remote_manifest.json');
+    final uri = _remoteManifestUri(gameId);
     final response = await client.get(uri);
     if (response.statusCode != 200) {
       throw HttpException(
@@ -143,6 +176,19 @@ class RemoteGamePackageRepository implements GamePackageRepository {
     );
   }
 
+  Uri _remoteManifestUri(String gameId) {
+    final uri = baseUri.resolve('$gameId/remote_manifest.json');
+    final query = Map<String, String>.from(uri.queryParameters)
+      ..addAll({
+        'runtimeApiVersion': runtimeApiVersion.toString(),
+        'runtimeVersion': runtimeOptions.runtimeVersion,
+        'hostBuild': runtimeOptions.hostBuild.toString(),
+        'platform': _platformName(runtimeOptions.platform),
+        'channel': runtimeOptions.channel,
+      });
+    return uri.replace(queryParameters: query);
+  }
+
   Future<Directory> _downloadAndExtract(
     http.Client client,
     String gameId,
@@ -200,12 +246,14 @@ class RemotePackageManifest {
     required this.version,
     required this.packageUrl,
     required this.sha256,
+    this.compatibility = const RemotePackageCompatibility(),
   });
 
   final String gameId;
   final String version;
   final Uri packageUrl;
   final String sha256;
+  final RemotePackageCompatibility compatibility;
 
   static RemotePackageManifest fromMap(Map<String, Object?> map) {
     return RemotePackageManifest(
@@ -213,6 +261,7 @@ class RemotePackageManifest {
       version: _string(map, 'version'),
       packageUrl: Uri.parse(_string(map, 'packageUrl')),
       sha256: _string(map, 'sha256'),
+      compatibility: RemotePackageCompatibility.fromMap(map['compat']),
     );
   }
 
@@ -224,3 +273,182 @@ class RemotePackageManifest {
     throw FormatException('remote_manifest.$key must be a non-empty string');
   }
 }
+
+class RemotePackageCompatibility {
+  const RemotePackageCompatibility({
+    this.runtimeApiVersion,
+    this.minRuntimeVersion,
+    this.maxRuntimeVersion,
+    this.minHostBuild,
+    this.maxHostBuild,
+    this.platforms = const [],
+    this.channels = const [],
+  });
+
+  final int? runtimeApiVersion;
+  final String? minRuntimeVersion;
+  final String? maxRuntimeVersion;
+  final int? minHostBuild;
+  final int? maxHostBuild;
+  final List<String> platforms;
+  final List<String> channels;
+
+  static RemotePackageCompatibility fromMap(Object? value) {
+    if (value == null) {
+      return const RemotePackageCompatibility();
+    }
+    if (value is! Map) {
+      throw const FormatException('remote_manifest.compat must be a map');
+    }
+    final map = Map<String, Object?>.from(value);
+    return RemotePackageCompatibility(
+      runtimeApiVersion: _optionalInt(map, 'runtimeApiVersion'),
+      minRuntimeVersion: _optionalString(map, 'minRuntimeVersion'),
+      maxRuntimeVersion: _optionalString(map, 'maxRuntimeVersion'),
+      minHostBuild: _optionalInt(map, 'minHostBuild'),
+      maxHostBuild: _optionalInt(map, 'maxHostBuild'),
+      platforms: _optionalStringList(map, 'platforms'),
+      channels: _optionalStringList(map, 'channels'),
+    );
+  }
+
+  void verify({
+    required int runtimeApiVersion,
+    required RuntimeOptions runtimeOptions,
+  }) {
+    if (this.runtimeApiVersion != null &&
+        this.runtimeApiVersion != runtimeApiVersion) {
+      throw const FormatException('Remote package runtimeApiVersion mismatch');
+    }
+    if (minRuntimeVersion != null &&
+        _compareVersions(runtimeOptions.runtimeVersion, minRuntimeVersion!) <
+            0) {
+      throw const FormatException('Remote package requires newer runtime');
+    }
+    if (maxRuntimeVersion != null &&
+        _compareVersions(runtimeOptions.runtimeVersion, maxRuntimeVersion!) >
+            0) {
+      throw const FormatException(
+        'Remote package does not support this runtime',
+      );
+    }
+    if (minHostBuild != null && runtimeOptions.hostBuild < minHostBuild!) {
+      throw const FormatException('Remote package requires newer host build');
+    }
+    if (maxHostBuild != null && runtimeOptions.hostBuild > maxHostBuild!) {
+      throw const FormatException(
+        'Remote package does not support this host build',
+      );
+    }
+    final platform = _platformName(runtimeOptions.platform);
+    if (platforms.isNotEmpty && !platforms.contains(platform)) {
+      throw const FormatException(
+        'Remote package does not support this platform',
+      );
+    }
+    if (channels.isNotEmpty && !channels.contains(runtimeOptions.channel)) {
+      throw const FormatException(
+        'Remote package does not support this channel',
+      );
+    }
+  }
+
+  static String? _optionalString(Map<String, Object?> map, String key) {
+    final value = map[key];
+    if (value == null) {
+      return null;
+    }
+    if (value is String && value.isNotEmpty) {
+      return value;
+    }
+    throw FormatException('remote_manifest.compat.$key must be a string');
+  }
+
+  static int? _optionalInt(Map<String, Object?> map, String key) {
+    final value = map[key];
+    if (value == null) {
+      return null;
+    }
+    if (value is num) {
+      return value.toInt();
+    }
+    throw FormatException('remote_manifest.compat.$key must be an integer');
+  }
+
+  static List<String> _optionalStringList(
+    Map<String, Object?> map,
+    String key,
+  ) {
+    final value = map[key];
+    if (value == null) {
+      return const [];
+    }
+    if (value is! List) {
+      throw FormatException(
+        'remote_manifest.compat.$key must be a string list',
+      );
+    }
+    return value
+        .map((item) {
+          if (item is String && item.isNotEmpty) {
+            return item;
+          }
+          throw FormatException(
+            'remote_manifest.compat.$key must be a string list',
+          );
+        })
+        .toList(growable: false);
+  }
+}
+
+String _platformName(String? explicitPlatform) {
+  if (explicitPlatform != null && explicitPlatform.isNotEmpty) {
+    return explicitPlatform;
+  }
+  if (Platform.isAndroid) {
+    return 'android';
+  }
+  if (Platform.isIOS) {
+    return 'ios';
+  }
+  if (Platform.isMacOS) {
+    return 'macos';
+  }
+  if (Platform.isWindows) {
+    return 'windows';
+  }
+  if (Platform.isLinux) {
+    return 'linux';
+  }
+  if (Platform.isFuchsia) {
+    return 'fuchsia';
+  }
+  return 'unknown';
+}
+
+int _compareVersions(String left, String right) {
+  final leftParts = _versionParts(left);
+  final rightParts = _versionParts(right);
+  final count = leftParts.length > rightParts.length
+      ? leftParts.length
+      : rightParts.length;
+  for (var index = 0; index < count; index++) {
+    final leftValue = index < leftParts.length ? leftParts[index] : 0;
+    final rightValue = index < rightParts.length ? rightParts[index] : 0;
+    if (leftValue != rightValue) {
+      return leftValue.compareTo(rightValue);
+    }
+  }
+  return 0;
+}
+
+List<int> _versionParts(String value) {
+  final normalized = value.split('-').first;
+  return normalized
+      .split('.')
+      .map((part) {
+        final digits = RegExp(r'^\d+').firstMatch(part)?.group(0);
+        return int.tryParse(digits ?? '') ?? 0;
+      })
+      .toList(growable: false);
+}