Various search UI improvements

ts/components/leftPane/handleKeydownForSearch.ts

@@ -0,0 +1,33 @@
+// Copyright 2021 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+export function handleKeydownForSearch(
+  event: Readonly<KeyboardEvent>,
+  {
+    searchInConversation,
+    selectedConversationId,
+    startSearch,
+  }: Readonly<{
+    searchInConversation: (conversationId: string) => unknown;
+    selectedConversationId: undefined | string;
+    startSearch: () => unknown;
+  }>
+): void {
+  const { ctrlKey, metaKey, shiftKey, key } = event;
+  const commandKey = window.platform === 'darwin' && metaKey;
+  const controlKey = window.platform !== 'darwin' && ctrlKey;
+  const commandOrCtrl = commandKey || controlKey;
+  const commandAndCtrl = commandKey && ctrlKey;
+
+  if (commandOrCtrl && !commandAndCtrl && key.toLowerCase() === 'f') {
+    if (!shiftKey) {
+      startSearch();
+      event.preventDefault();
+      event.stopPropagation();
+    } else if (selectedConversationId) {
+      searchInConversation(selectedConversationId);
+      event.preventDefault();
+      event.stopPropagation();
+    }
+  }
+}