Update shell

src/main.c

@@ -50,6 +50,23 @@ static int s_mars_depth = 0;
 #define PAUSE_ITEM_COUNT 3
 static int s_pause_selection = 0; /* 0=Resume, 1=Restart, 2=Quit */
 
+#ifdef __EMSCRIPTEN__
+/* JS-initiated level load request (level-select dropdown in shell). */
+static int  s_js_load_request = 0;
+static char          s_js_load_path[ASSET_PATH_MAX] = {0};
+#endif
+
+#ifdef __EMSCRIPTEN__
+/* Called from the JS shell level-select dropdown to load a level into
+ * gameplay mode. Sets a deferred request that game_update() picks up on
+ * the next frame so we don't mutate game state from an arbitrary call site. */
+EMSCRIPTEN_KEEPALIVE
+void game_load_level(const char *path) {
+    snprintf(s_js_load_path, sizeof(s_js_load_path), "%s", path);
+    s_js_load_request = 1;
+}
+#endif
+
 static const char *theme_name(LevelTheme t) {
     switch (t) {
         case THEME_PLANET_SURFACE: return "Planet Surface";
@@ -343,6 +360,39 @@ static void pause_update(void) {
 }
 
 static void game_update(float dt) {
+#ifdef __EMSCRIPTEN__
+    /* Handle deferred level load from JS shell dropdown. */
+    if (s_js_load_request && s_js_load_path[0]) {
+        s_js_load_request = 0;
+
+        /* Tear down whatever mode we are in. */
+        if (s_mode == MODE_PLAY || s_mode == MODE_PAUSED) {
+            level_free(&s_level);
+        } else if (s_mode == MODE_EDITOR) {
+            editor_free(&s_editor);
+        }
+
+        s_mode = MODE_PLAY;
+        s_testing_from_editor = false;
+
+        if (!load_level_file(s_js_load_path)) {
+            fprintf(stderr, "Failed to load level from shell: %s\n",
+                    s_js_load_path);
+            /* Fall back to the first campaign level. */
+            if (!load_level_file("assets/levels/moon01.lvl")) {
+                g_engine.running = false;
+            }
+        }
+
+        /* Also seed the editor path so pressing E opens this level. */
+        snprintf(s_edit_path, sizeof(s_edit_path), "%s", s_js_load_path);
+        s_js_load_path[0] = '\0';
+
+        SDL_SetWindowTitle(g_engine.window, "Jump 'n Run");
+        return;
+    }
+#endif
+
     if (s_mode == MODE_EDITOR) {
         editor_update(&s_editor, dt);