refactor(editor): rename block-std to std (#11250)

Closes: BS-2946

blocksuite/framework/std/src/clipboard/utils.ts

@@ -0,0 +1,33 @@
+import type { RootContentMap } from 'hast';
+
+type HastUnionType<
+  K extends keyof RootContentMap,
+  V extends RootContentMap[K],
+> = V;
+
+export function onlyContainImgElement(
+  ast: HastUnionType<keyof RootContentMap, RootContentMap[keyof RootContentMap]>
+): 'yes' | 'no' | 'maybe' {
+  if (ast.type === 'element') {
+    switch (ast.tagName) {
+      case 'html':
+      case 'body':
+        return ast.children.map(onlyContainImgElement).reduce((a, b) => {
+          if (a === 'no' || b === 'no') {
+            return 'no';
+          }
+          if (a === 'maybe' && b === 'maybe') {
+            return 'maybe';
+          }
+          return 'yes';
+        }, 'maybe');
+      case 'img':
+        return 'yes';
+      case 'head':
+        return 'maybe';
+      default:
+        return 'no';
+    }
+  }
+  return 'maybe';
+}