const PAGE = "https://example.com/browser/toolkit/content/tests/browser/file_multipleAudio.html";

var SuspendedType = {
  NONE_SUSPENDED             : 0,
  SUSPENDED_PAUSE            : 1,
  SUSPENDED_BLOCK            : 2,
  SUSPENDED_PAUSE_DISPOSABLE : 3
};

function* wait_for_tab_playing_event(tab, expectPlaying) {
  if (tab.soundPlaying == expectPlaying) {
    ok(true, "The tab should " + (expectPlaying ? "" : "not ") + "be playing");
  } else {
    yield BrowserTestUtils.waitForEvent(tab, "TabAttrModified", false, (event) => {
      if (event.detail.changed.indexOf("soundplaying") >= 0) {
        is(tab.soundPlaying, expectPlaying, "The tab should " + (expectPlaying ? "" : "not ") + "be playing");
        return true;
      }
      return false;
    });
  }
}

function check_audio_suspended(suspendedType) {
  var autoPlay = content.document.getElementById('autoplay');
  if (!autoPlay) {
    ok(false, "Can't get the audio element!");
  }

  is(autoPlay.computedSuspended, suspendedType,
     "The suspeded state of autoplay audio is correct.");
}

add_task(function* setup_test_preference() {
  yield new Promise(resolve => {
    SpecialPowers.pushPrefEnv({"set": [
      ["media.useAudioChannelService.testing", true],
      ["media.block-autoplay-until-in-foreground", true]
    ]}, resolve);
  });
});

add_task(function* block_autoplay_media() {
  info("- open new background tab1 -");
  let tab1 = window.gBrowser.addTab("about:blank");
  tab1.linkedBrowser.loadURI(PAGE);
  yield BrowserTestUtils.browserLoaded(tab1.linkedBrowser);

  info("- should block autoplay media for non-visited tab1 -");
  yield ContentTask.spawn(tab1.linkedBrowser, SuspendedType.SUSPENDED_BLOCK,
                          check_audio_suspended);

  info("- open new background tab2 -");
  let tab2 = window.gBrowser.addTab("about:blank");
  tab2.linkedBrowser.loadURI(PAGE);
  yield BrowserTestUtils.browserLoaded(tab2.linkedBrowser);

  info("- should block autoplay for non-visited tab2 -");
  yield ContentTask.spawn(tab2.linkedBrowser, SuspendedType.SUSPENDED_BLOCK,
                          check_audio_suspended);

  info("- select tab1 as foreground tab -");
  yield BrowserTestUtils.switchTab(window.gBrowser, tab1);

  info("- media should be unblocked because the tab was visited -");
  yield wait_for_tab_playing_event(tab1, true);
  yield ContentTask.spawn(tab1.linkedBrowser, SuspendedType.NONE_SUSPENDED,
                          check_audio_suspended);

  info("- open another new foreground tab3 -");
  let tab3 = yield BrowserTestUtils.openNewForegroundTab(window.gBrowser,
                                                         "about:blank");
  info("- should still play media from tab1 -");
  yield wait_for_tab_playing_event(tab1, true);
  yield ContentTask.spawn(tab1.linkedBrowser, SuspendedType.NONE_SUSPENDED,
                          check_audio_suspended);

  info("- should still block media from tab2 -");
  yield wait_for_tab_playing_event(tab2, false);
  yield ContentTask.spawn(tab2.linkedBrowser, SuspendedType.SUSPENDED_BLOCK,
                          check_audio_suspended);

  info("- remove tabs -");
  yield BrowserTestUtils.removeTab(tab1);
  yield BrowserTestUtils.removeTab(tab2);
  yield BrowserTestUtils.removeTab(tab3);
});