diff --git a/apps/ai-game-creator-shell/src/features/project-workspace/ResourceReferenceInput.tsx b/apps/ai-game-creator-shell/src/features/project-workspace/ResourceReferenceInput.tsx
index 7deef1bc7..ffbbe4035 100644
--- a/apps/ai-game-creator-shell/src/features/project-workspace/ResourceReferenceInput.tsx
+++ b/apps/ai-game-creator-shell/src/features/project-workspace/ResourceReferenceInput.tsx
@@ -300,6 +300,22 @@ function applyContentToRoot(
   });
 }
 
+/**
+ * 取当前可用的选区：选区缺失、或指向已被重建掉的节点时（跨会话恢复草稿后就是这种），
+ * 统一回落到草稿末尾，避免把内容插到一个已经不存在的位置。取不到时返回 `null`。
+ */
+function $selectionOrRootEnd() {
+  let selection = $getSelection();
+  if (
+    !$isRangeSelection(selection) ||
+    !selection.anchor.getNode().isAttached()
+  ) {
+    $getRoot().selectEnd();
+    selection = $getSelection();
+  }
+  return $isRangeSelection(selection) ? selection : null;
+}
+
 /**
  * 粘贴插入：在光标处就地插入 content 对应的节点，正文其余部分逐字不动。
  *
@@ -311,31 +327,19 @@ function $insertContentAtSelection(
   content: readonly DirectCodexUserContentPart[],
   providers: readonly ReferenceProvider[],
 ) {
-  // 与 insertReferences 同一处置：选区可能指向已被重建掉的节点，统一回落到草稿末尾。
-  // 每插一段都重新取一次选区：插入会移动光标，缓存下来的那个 RangeSelection 会过期。
-  const currentSelection = () => {
-    let selection = $getSelection();
-    if (
-      !$isRangeSelection(selection) ||
-      !selection.anchor.getNode().isAttached()
-    ) {
-      $getRoot().selectEnd();
-      selection = $getSelection();
-    }
-    return $isRangeSelection(selection) ? selection : null;
-  };
-  if (!currentSelection()) return;
+  // 每插一段都重新取一次选区：插入会移动光标，上一轮拿到的那个 RangeSelection 会过期。
+  if (!$selectionOrRootEnd()) return;
   content.forEach((part) => {
     if (part.type === 'input_text') {
       part.text.split('\n').forEach((line, index) => {
-        if (index > 0) currentSelection()?.insertParagraph();
-        if (line) currentSelection()?.insertText(line);
+        if (index > 0) $selectionOrRootEnd()?.insertParagraph();
+        if (line) $selectionOrRootEnd()?.insertText(line);
       });
       return;
     }
     const reference = referenceFromPart(providers, part);
     if (reference) {
-      currentSelection()?.insertNodes([
+      $selectionOrRootEnd()?.insertNodes([
         $createResourceReferenceNode(reference),
       ]);
     }
@@ -413,24 +417,14 @@ function ResourceReferenceEditor({
     (nextReferences: ChatReference[]) => {
       if (nextReferences.length === 0) return;
       editor.update(() => {
-        let selection = $getSelection();
-        // 跨会话恢复草稿后选区可能仍指向已被重建掉的节点，这里统一回落到草稿末尾，
-        // 避免把引用插到一个已经不存在的位置。
-        if (
-          !$isRangeSelection(selection) ||
-          !selection.anchor.getNode().isAttached()
-        ) {
-          $getRoot().selectEnd();
-          selection = $getSelection();
-        }
-        if ($isRangeSelection(selection)) {
-          selection.insertNodes(
-            nextReferences.flatMap((reference) => [
-              $createResourceReferenceNode(reference),
-              $createTextNode(' '),
-            ]),
-          );
-        }
+        const selection = $selectionOrRootEnd();
+        if (!selection) return;
+        selection.insertNodes(
+          nextReferences.flatMap((reference) => [
+            $createResourceReferenceNode(reference),
+            $createTextNode(' '),
+          ]),
+        );
       });
       editor.focus();
     },
@@ -442,19 +436,11 @@ function ResourceReferenceEditor({
       const insert = text.replace(/\s+$/u, '');
       if (!insert.trim()) return;
       editor.update(() => {
-        let selection = $getSelection();
-        if (
-          !$isRangeSelection(selection) ||
-          !selection.anchor.getNode().isAttached()
-        ) {
-          $getRoot().selectEnd();
-          selection = $getSelection();
-        }
-        if ($isRangeSelection(selection)) {
-          const rootText = $getRoot().getTextContent();
-          if (rootText && !/\s$/u.test(rootText)) selection.insertText(' ');
-          selection.insertText(insert);
-        }
+        const selection = $selectionOrRootEnd();
+        if (!selection) return;
+        const rootText = $getRoot().getTextContent();
+        if (rootText && !/\s$/u.test(rootText)) selection.insertText(' ');
+        selection.insertText(insert);
       });
       editor.focus();
     },