migrate app focus logic to events sent from node

ts/hooks/useAppFocused.ts

@@ -1,36 +1,25 @@
-import { app } from 'electron';
-import { useCallback, useEffect } from 'react';
+import { useEffect } from 'react';
 import { useDispatch, useSelector } from 'react-redux';
-import { isElectronWindowFocused } from '../session/utils/WindowUtils';
 import { setIsAppFocused } from '../state/ducks/section';
 import { getIsAppFocused } from '../state/selectors/section';
+import { ipcRenderer } from 'electron';
 
+/**
+ * This custom hook should be called on the top of the app only once.
+ * It sets up a listener for events from main_node.ts and update the global redux state with the focused state.
+ */
 export function useAppIsFocused() {
   const dispatch = useDispatch();
   const isFocused = useSelector(getIsAppFocused);
 
-  useEffect(() => {
-    dispatch(setIsAppFocused(isElectronWindowFocused()));
-  }, []);
-
-  const onFocusCallback = useCallback((_event, win) => {
-    if (win.webContents.id === 1) {
-      dispatch(setIsAppFocused(true));
-    }
-  }, []);
-
-  const onBlurCallback = useCallback((_event, win) => {
-    if (win.webContents.id === 1) {
-      dispatch(setIsAppFocused(false));
-    }
-  }, []);
+  const ipcCallback = (_event: unknown, isFocused: unknown) => {
+    dispatch(setIsAppFocused(Boolean(isFocused)));
+  };
 
   useEffect(() => {
-    // app.on('browser-window-focus', onFocusCallback);
-    // app.on('browser-window-blur', onBlurCallback);
+    ipcRenderer.on('set-window-focus', ipcCallback);
     return () => {
-      // app.removeListener('browser-window-blur', onBlurCallback);
-      // app.removeListener('browser-window-focus', onFocusCallback);
+      ipcRenderer.removeListener('set-window-focus', ipcCallback);
     };
   });
 

ts/mains/main_node.ts

@@ -311,6 +311,18 @@ async function createWindow() {
   mainWindow = new BrowserWindow(windowOptions);
   setupSpellChecker(mainWindow, locale.messages);
 
+  const setWindowFocus = () => {
+    if (!mainWindow) {
+      return;
+    }
+    mainWindow.webContents.send('set-window-focus', mainWindow.isFocused());
+  };
+  mainWindow.on('focus', setWindowFocus);
+  mainWindow.on('blur', setWindowFocus);
+  mainWindow.once('ready-to-show', setWindowFocus);
+  // This is a fallback in case we drop an event for some reason.
+  global.setInterval(setWindowFocus, 5000);
+
   electronLocalshortcut.register(mainWindow, 'F5', () => {
     if (!mainWindow) {
       return;

ts/session/utils/WindowUtils.ts

@@ -1,9 +0,0 @@
-import { BrowserWindow } from 'electron';
-
-export function isElectronWindowFocused() {
-  // const [yourBrowserWindow] = BrowserWindow.getAllWindows();
-  // const isFocused = yourBrowserWindow?.isFocused() || false;
-  // throw new Error('TOFIX');
-  return false;
-  return isFocused;
-}