chore: Move editor into codebase (#2930)

shared/utils/getDataTransferFiles.ts

@@ -0,0 +1,28 @@
+export default function getDataTransferFiles(
+  event:
+    | Event
+    | React.FormEvent<HTMLInputElement>
+    | React.DragEvent<HTMLElement>
+): File[] {
+  let dataTransferItemsList!: FileList | DataTransferItemList;
+
+  if ("dataTransfer" in event) {
+    const dt = event.dataTransfer;
+
+    if (dt.files && dt.files.length) {
+      dataTransferItemsList = dt.files;
+    } else if (dt.items && dt.items.length) {
+      // During the drag even the dataTransfer.files is null
+      // but Chrome implements some drag store, which is accesible via dataTransfer.items
+      dataTransferItemsList = dt.items;
+    }
+  } else if (event.target && "files" in event.target) {
+    // @ts-expect-error fallback
+    dataTransferItemsList = event.target.files;
+  }
+
+  // Convert from DataTransferItemsList to the native Array
+  return dataTransferItemsList
+    ? Array.prototype.slice.call(dataTransferItemsList)
+    : [];
+}