Rename files

ts/main/NativeThemeNotifier.main.ts

@@ -0,0 +1,46 @@
+// Copyright 2021 Signal Messenger, LLC
+// SPDX-License-Identifier: AGPL-3.0-only
+
+import type { BrowserWindow } from 'electron';
+import { ipcMain as ipc, nativeTheme } from 'electron';
+
+import type { NativeThemeState } from '../types/NativeThemeNotifier.d.ts';
+
+function getState(): NativeThemeState {
+  return {
+    shouldUseDarkColors: nativeTheme.shouldUseDarkColors,
+  };
+}
+
+export class NativeThemeNotifier {
+  readonly #listeners = new Set<BrowserWindow>();
+
+  public initialize(): void {
+    nativeTheme.on('updated', () => {
+      this.#notifyListeners();
+    });
+
+    ipc.on('native-theme:init', event => {
+      // eslint-disable-next-line no-param-reassign
+      event.returnValue = getState();
+    });
+  }
+
+  public addWindow(window: BrowserWindow): void {
+    if (this.#listeners.has(window)) {
+      return;
+    }
+
+    this.#listeners.add(window);
+
+    window.once('closed', () => {
+      this.#listeners.delete(window);
+    });
+  }
+
+  #notifyListeners(): void {
+    for (const window of this.#listeners) {
+      window.webContents.send('native-theme:changed', getState());
+    }
+  }
+}