Initial flame_lua_runtime package

tool/generate_lua_runtime_defs.dart

@@ -0,0 +1,93 @@
+import 'dart:io';
+
+const _commonPath = 'tool/lua_runtime_defs_common.lua';
+const _runtimeMarker = 'runtime = runtime';
+const _gamesRoot = 'assets/games';
+
+void main(List<String> args) {
+  final checkOnly = args.contains('--check');
+  final commonFile = File(_commonPath);
+  if (!commonFile.existsSync()) {
+    stderr.writeln('Missing common Lua runtime defs template: $_commonPath');
+    exitCode = 1;
+    return;
+  }
+
+  final common = _normalizeCommon(commonFile.readAsStringSync());
+  var changed = false;
+  final targets = _runtimeDefTargets();
+  if (targets.isEmpty) {
+    stderr.writeln('No Lua runtime defs targets found under $_gamesRoot');
+    exitCode = 1;
+    return;
+  }
+
+  for (final target in targets) {
+    final targetPath = target.path;
+    final current = target.existsSync() ? target.readAsStringSync() : '';
+    final suffix = current.isEmpty
+        ? ''
+        : _gameSpecificSuffix(current, targetPath);
+    final generated = suffix.isEmpty ? common : '$common\n$suffix';
+
+    if (current == generated) {
+      stdout.writeln('up to date: $targetPath');
+      continue;
+    }
+
+    changed = true;
+    if (checkOnly) {
+      stderr.writeln('out of date: $targetPath');
+    } else {
+      target.writeAsStringSync(generated);
+      stdout.writeln('generated: $targetPath');
+    }
+  }
+
+  if (checkOnly && changed) {
+    stderr.writeln(
+      'Lua runtime defs are out of date. Run: dart run tool/generate_lua_runtime_defs.dart',
+    );
+    exitCode = 1;
+  }
+}
+
+List<File> _runtimeDefTargets() {
+  final root = Directory(_gamesRoot);
+  if (!root.existsSync()) {
+    return const [];
+  }
+  final targets = <File>[];
+  for (final entity in root.listSync()) {
+    if (entity is! Directory) {
+      continue;
+    }
+    final scripts = Directory('${entity.path}/scripts');
+    if (!scripts.existsSync()) {
+      continue;
+    }
+    targets.add(File('${scripts.path}/runtime_defs.lua'));
+  }
+  targets.sort((a, b) => a.path.compareTo(b.path));
+  return targets;
+}
+
+String _normalizeCommon(String source) {
+  final text = source.replaceAll('\r\n', '\n').trimRight();
+  if (!text.contains(_runtimeMarker)) {
+    throw const FormatException(
+      'Common template must contain runtime = runtime',
+    );
+  }
+  return '$text\n';
+}
+
+String _gameSpecificSuffix(String source, String targetPath) {
+  final text = source.replaceAll('\r\n', '\n');
+  final index = text.indexOf(_runtimeMarker);
+  if (index < 0) {
+    throw FormatException('$targetPath must contain $_runtimeMarker');
+  }
+  final suffixStart = index + _runtimeMarker.length;
+  return text.substring(suffixStart).trimLeft();
+}