backsplash-app/src/windowState.ts

An AI powered wallpaper app.

import { sendToRenderer } from "src/webContents";

export type WindowState = "minimized" | "normal" | "maximized" | "full-screen" | "hidden";

export function getWindowState(window: Electron.BrowserWindow): WindowState {
  if (window.isFullScreen()) {
    return "full-screen";
  } else if (window.isMaximized()) {
    return "maximized";
  } else if (window.isMinimized()) {
    return "minimized";
  } else if (!window.isVisible()) {
    return "hidden";
  } else {
    return "normal";
  }
}

/**
 * Registers event handlers for all window state transition events and
 * forwards those to the renderer process for a given window.
 */
export function registerWindowStateChangedEvents(window: Electron.BrowserWindow) {
  window.on("enter-full-screen", () => sendWindowStateEvent(window, "full-screen"));

  // So this is a bit of a hack. If we call window.isFullScreen directly after
  // receiving the leave-full-screen event it'll return true which isn't what
  // we're after. So we'll say that we're transitioning to 'normal' even though
  // we might be maximized. This works because electron will emit a 'maximized'
  // event after 'leave-full-screen' if the state prior to full-screen was maximized.
  window.on("leave-full-screen", () => sendWindowStateEvent(window, "normal"));

  window.on("maximize", () => sendWindowStateEvent(window, "maximized"));
  window.on("minimize", () => sendWindowStateEvent(window, "minimized"));
  window.on("unmaximize", () => sendWindowStateEvent(window, "normal"));
  window.on("restore", () => sendWindowStateEvent(window, "normal"));
  window.on("hide", () => sendWindowStateEvent(window, "hidden"));
  window.on("show", () => {
    // because the app can be maximized before being closed - which will restore it
    // maximized on the next launch - this function should inspect the current state
    // rather than always assume it is a 'normal' launch
    sendWindowStateEvent(window, getWindowState(window));
  });
}

function sendWindowStateEvent(window: Electron.BrowserWindow, state: WindowState) {
  sendToRenderer(window.webContents, "window-state-changed", state);
}