refactor for shared states and multi chapters

assets/js/games/engine/scene-registry.js

@@ -0,0 +1,66 @@
+// Scene Registry - Global registry for shared scene factories
+// Scene factories are functions that take a context and return scene definitions
+
+// Initialize global scene factories object
+window.SceneFactories = window.SceneFactories || {};
+
+// Helper class for working with scene factories
+class SceneRegistry {
+  // Register a scene factory
+  static register(id, factory) {
+    if (typeof factory !== "function") {
+      console.error(`Scene factory must be a function: ${id}`);
+      return false;
+    }
+    window.SceneFactories[id] = factory;
+    return true;
+  }
+
+  // Get a scene factory
+  static get(id) {
+    return window.SceneFactories[id] || null;
+  }
+
+  // Check if a factory exists
+  static has(id) {
+    return id in window.SceneFactories;
+  }
+
+  // List all registered factories
+  static list() {
+    return Object.keys(window.SceneFactories);
+  }
+
+  // Unregister a factory
+  static unregister(id) {
+    delete window.SceneFactories[id];
+  }
+
+  // Create scenes from a factory with context
+  static createScenes(id, context) {
+    const factory = this.get(id);
+    if (!factory) {
+      console.warn(`Scene factory not found: ${id}`);
+      return {};
+    }
+    try {
+      return factory(context);
+    } catch (e) {
+      console.error(`Error creating scenes from factory ${id}:`, e);
+      return {};
+    }
+  }
+
+  // Merge multiple factories into one scene object
+  static mergeFactories(factoryIds, context) {
+    const merged = {};
+    for (const id of factoryIds) {
+      const scenes = this.createScenes(id, context);
+      Object.assign(merged, scenes);
+    }
+    return merged;
+  }
+}
+
+// Make available globally
+window.SceneRegistry = SceneRegistry;