/*
 * Beamer Viewer, a web-based PDF presentation viewer
 * Copyright 2018-2024 Pacien TRAN-GIRARD
 * SPDX-License-Identifier: EUPL-1.2
 */

"use strict";

class Stage {
  constructor(onReady, onNext, onPrevious) {
    this.audienceScreen = null;
    this.presenterScreen = null;

    this.onReady = onReady;
    this.eventHandlers = [
      new KeyboardEventHandler(onNext, onPrevious),
      new MouseClickEventHandler(onNext, onPrevious),
      new TouchSwipeEventHandler(onNext, onPrevious)
    ];
  }

  start() {
    this.projector = window.open(window.location.href, "_blank", "toolbar=0,location=0,menubar=0");
    if (this.projector == null)
      alert("Please allow pop-ups, then refresh this page.");

    this.projector.addEventListener("load", () => {
      this.audienceScreen = new Screen(this.projector, false, false);
      this.presenterScreen = new Screen(window, true, true);
      this._watchDetach();
      this.onReady();
    });

    this._registerEventHandler(window);
    this._registerEventHandler(this.projector);
  }

  setPage(page) {
    this.audienceScreen.setPage(page);
    this.presenterScreen.setPage(page);
  }

  _registerEventHandler(window) {
    if (window == null) return;

    this.eventHandlers
      .forEach(eventHandler => eventHandler.register(window));
  }

  _watchDetach() {
    window.addEventListener("beforeunload", () =>
      this._setMessage(this.projector, "Controller detached")
    );

    this.projector.addEventListener("beforeunload", () =>
      this._setMessage(window, "Viewer detached")
    );
  }

  _setMessage(window, message) {
    const messageBar = window.document.getElementById("message");
    messageBar.textContent = message;
  }
}