Transcode heic/heif images

ts/workers/heicConverterMain.ts

@@ -0,0 +1,68 @@
+// Copyright 2021 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import { join } from 'path';
+import { Worker } from 'worker_threads';
+
+export type WrappedWorkerRequest = {
+  readonly uuid: string;
+  readonly data: ArrayBuffer;
+};
+
+export type WrappedWorkerResponse = {
+  readonly uuid: string;
+  readonly error: string | undefined;
+  readonly response?: File;
+};
+
+const ASAR_PATTERN = /app\.asar$/;
+
+export function getHeicConverter(): (
+  uuid: string,
+  data: ArrayBuffer
+) => Promise<WrappedWorkerResponse> {
+  let appDir = join(__dirname, '..', '..');
+  let isBundled = false;
+  if (ASAR_PATTERN.test(appDir)) {
+    appDir = appDir.replace(ASAR_PATTERN, 'app.asar.unpacked');
+    isBundled = true;
+  }
+  const scriptDir = join(appDir, 'ts', 'workers');
+  const worker = new Worker(
+    join(
+      scriptDir,
+      isBundled ? 'heicConverter.bundle.js' : 'heicConverterWorker.js'
+    )
+  );
+
+  const ResponseMap = new Map<
+    string,
+    (response: WrappedWorkerResponse) => void
+  >();
+
+  worker.on('message', (wrappedResponse: WrappedWorkerResponse) => {
+    const { uuid } = wrappedResponse;
+
+    const resolve = ResponseMap.get(uuid);
+    if (!resolve) {
+      throw new Error(`Cannot find resolver for ${uuid}`);
+    }
+
+    resolve(wrappedResponse);
+  });
+
+  return async (uuid, data) => {
+    const wrappedRequest: WrappedWorkerRequest = {
+      uuid,
+      data,
+    };
+
+    const result = new Promise<WrappedWorkerResponse>(resolve => {
+      ResponseMap.set(uuid, resolve);
+    });
+
+    worker.postMessage(wrappedRequest);
+
+    return result;
+  };
+}