Simplify loader helpers

src/main.js

@@ -1,14 +1,15 @@
 (() => {
   const { World, Body, Constraint, Events, Vector } = Matter;
 
-  const fromWindow = (key, fallback = {}) => window[key] ?? fallback;
+  const load = (key, { create, fallback = {} } = {}) => {
-
+    const mod = window[key] ?? fallback;
-  const getFactory = (key, fallbackFactory) => {
+    if (!create) return mod;
-    const mod = fromWindow(key);
+    return typeof mod[create] === "function" ? mod[create].bind(mod) : fallback;
-    return typeof mod.create === "function" ? mod.create : fallbackFactory;
   };
 
-  const createConfig = getFactory("PhysilinksConfig", () => ({
+  const createConfig = load("PhysilinksConfig", {
+    create: "create",
+    fallback: () => ({
       config: {},
       defaultMessageConfig: {
         durationMs: 4200,
@@ -16,7 +17,8 @@
         text: null,
         colors: null,
       },
-  }));
+    }),
+  });
 
   const { config: baseConfig, defaultMessageConfig } = createConfig();
 
@@ -64,16 +66,14 @@
     config.messages = normalized.messages;
   };
 
-  const {
+  const scenesMod = load("PhysilinksScenes", { fallback: {} });
-    scenes = [],
+  const { scenes = [], defaultSceneId, order: sceneOrder = [] } = scenesMod;
-    defaultSceneId,
-    order: sceneOrder = [],
-  } = fromWindow("PhysilinksScenes", {});
 
+  const registry = load("PhysilinksSceneRegistry", { fallback: {} });
   const { getSceneById, getSceneIdFromUrl, setSceneIdInUrl, getNextSceneId } =
-    fromWindow("PhysilinksSceneRegistry", {});
+    registry;
 
-  const createUI = getFactory("PhysilinksUI");
+  const createUI = load("PhysilinksUI", { create: "create" });
   const ui = createUI();
   const { sceneEl } = ui;
 
@@ -99,7 +99,7 @@
 
   const BALL_BASELINE = 680; // reference height used for relative ball sizing
 
-  const createEngine = getFactory("PhysilinksEngine");
+  const createEngine = load("PhysilinksEngine", { create: "create" });
   const { engine, render, runner, startRunner, stopRunner, setRenderSize } =
     createEngine({
       sceneEl,
@@ -143,7 +143,7 @@
   let spawnSystem = null;
   let input = null;
 
-  const storage = fromWindow("PhysilinksStorage", {});
+  const storage = load("PhysilinksStorage", { fallback: {} });
   const {
     loadHighScore = () => 0,
     loadLongestChain = () => 0,
@@ -233,7 +233,7 @@
     ui.showGameOver(state.score);
   };
 
-  const createSpawn = getFactory("PhysilinksSpawn");
+  const createSpawn = load("PhysilinksSpawn", { create: "create" });
   spawnSystem = createSpawn({
     config,
     world,
@@ -246,7 +246,7 @@
     isGameOver: () => state.gameOver,
     ballBaseline: BALL_BASELINE,
   });
-  const createGoals = getFactory("PhysilinksGoals");
+  const createGoals = load("PhysilinksGoals", { create: "create" });
   const goals = createGoals({
     config,
     getCurrentScene: () => currentScene,
@@ -580,7 +580,7 @@
     goals.maybeAnnounceGoalProgress(goal);
   };
 
-  const createInput = getFactory("PhysilinksInput");
+  const createInput = load("PhysilinksInput", { create: "create" });
   input = createInput({
     render,
     world,