Moves DraftAttachments into redux

ts/util/handleVideoAttachment.ts

@@ -0,0 +1,43 @@
+// Copyright 2021 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { blobToArrayBuffer } from 'blob-util';
+
+import * as log from '../logging/log';
+import { makeVideoScreenshot } from '../types/VisualAttachment';
+import { IMAGE_PNG, stringToMIMEType } from '../types/MIME';
+import { InMemoryAttachmentDraftType } from '../types/Attachment';
+import { fileToBytes } from './fileToBytes';
+
+export async function handleVideoAttachment(
+  file: Readonly<File>
+): Promise<InMemoryAttachmentDraftType> {
+  const objectUrl = URL.createObjectURL(file);
+  if (!objectUrl) {
+    throw new Error('Failed to create object url for video!');
+  }
+  try {
+    const screenshotContentType = IMAGE_PNG;
+    const screenshotBlob = await makeVideoScreenshot({
+      objectUrl,
+      contentType: screenshotContentType,
+      logger: log,
+    });
+    const screenshotData = await blobToArrayBuffer(screenshotBlob);
+    const data = await fileToBytes(file);
+
+    return {
+      contentType: stringToMIMEType(file.type),
+      data,
+      fileName: file.name,
+      path: file.name,
+      pending: false,
+      screenshotContentType,
+      screenshotData: new Uint8Array(screenshotData),
+      screenshotSize: screenshotData.byteLength,
+      size: data.byteLength,
+    };
+  } finally {
+    URL.revokeObjectURL(objectUrl);
+  }
+}