function _createDiv(attrs) {
    var div = document.createElement("div");
    for (key in attrs) {
        div.setAttribute(key, attrs[key]);
    }
    document.body.appendChild(div);
    return div;
}

describe("The enumeration object", function () {
  it("BackgroundType should exist", function () {
    expect(BackgroundType).toBeDefined();
  });

  it("GradientType should exist", function () {
    expect(GradientType).toBeDefined();
  });

  it("HorizontalAlign should exist", function () {
    expect(HorizontalAlign).toBeDefined();
  });

  it("VerticalAlign should exist", function () {
    expect(VerticalAlign).toBeDefined();
  });

  it("AudioState should exist", function () {
    expect(AudioState).toBeDefined();
  });
});

describe("The function", function () {
  it("$() should return the right element", function () {
    var div = _createDiv({"id": "dollar-test"});
    expect($("#dollar-test")[0]).toBe(div);
  });

  it("_buildLinearGradient() should build the correct string", function () {
    var gradient = _buildLinearGradient("left top", "left bottom", "#000", "#fff");
    expect(gradient).toBe("-webkit-gradient(linear, left top, left bottom, from(#000), to(#fff)) fixed");
  });

  it("_buildRadialGradient() should build the correct string", function () {
    var gradient = _buildRadialGradient(10, "#000", "#fff");
    expect(gradient).toBe("-webkit-gradient(radial, 10 50%, 100, 10 50%, 10, from(#000), to(#fff)) fixed");
  });

  it("_getStyle should return the correct style on an element", function () {
    var div = _createDiv({"id": "style-test"});
    div.style.setProperty("width", "100px");
    expect(_getStyle($("#style-test")[0], "width")).toBe("100px");
  });

  it("_nl2br should turn UNIX newlines into <br> tags", function () {
    var text = "Amazing grace, how sweet the sound\nThat saved a wretch like me";
    expect(_nl2br(text)).toEqual("Amazing grace, how sweet the sound<br>That saved a wretch like me");
  });

  it("_nl2br should turn Windows newlines into <br> tags", function () {
    var text = "Amazing grace, how sweet the sound\r\nThat saved a wretch like me";
    expect(_nl2br(text)).toEqual("Amazing grace, how sweet the sound<br>That saved a wretch like me");
  });

  it("_prepareText should turn verse text into a paragraph", function () {
    var text = "Amazing grace, how sweet the sound\nThat saved a wretch like me";
    expect(_prepareText(text)).toEqual("<p>Amazing grace, how sweet the sound<br>That saved a wretch like me</p>");
  });
});

describe("The Display object", function () {
  it("should start with a blank _slides object", function () {
    expect(Display._slides).toEqual({});
  });

  it("should have the correct Reveal config", function () {
    expect(Display._revealConfig).toEqual({
      margin: 0.0,
      minScale: 1.0,
      maxScale: 1.0,
      controls: false,
      progress: false,
      history: false,
      overview: false,
      center: false,
      help: false,
      transition: "none",
      backgroundTransition: "none",
      viewDistance: 9999,
      width: "100%",
      height: "100%"
    });
  });

  it("should have an init() method", function () {
    expect(Display.init).toBeDefined();
  });

  it("should initialise Reveal when init is called", function () {
    spyOn(Reveal, "initialize");
    Display.init();
    expect(Reveal.initialize).toHaveBeenCalled();
  });

  it("should have a reinit() method", function () {
    expect(Display.reinit).toBeDefined();
  });

  it("should re-initialise Reveal when reinit is called", function () {
    spyOn(Reveal, "reinitialize");
    Display.reinit();
    expect(Reveal.reinitialize).toHaveBeenCalled();
  });

  it("should have a setTransition() method", function () {
    expect(Display.setTransition).toBeDefined();
  });

  it("should have a correctly functioning setTransition() method", function () {
    spyOn(Reveal, "configure");
    Display.setTransition("fade");
    expect(Reveal.configure).toHaveBeenCalledWith({"transition": "fade"});
  });

  it("should have a correctly functioning clearSlides() method", function () {
    expect(Display.clearSlides).toBeDefined();

    document.body.innerHTML = "";
    var slidesDiv = _createDiv({"class": "slides"});
    slidesDiv.innerHTML = "<section><p></p></section>";

    Display.clearSlides();
    expect($(".slides")[0].innerHTML).toEqual("");
    expect(Display._slides).toEqual({});
  });

  it("should have a correct goToSlide() method", function () {
    spyOn(Reveal, "slide");
    spyOn(Display, "_slides");
    Display._slides["v1"] = 0;

    Display.goToSlide("v1");
    expect(Reveal.slide).toHaveBeenCalledWith(0);
  });
});

describe("Display.addTextSlide", function () {
  beforeEach(function() {
    document.body.innerHTML = "";
    _createDiv({"class": "slides"});
    _createDiv({"class": "footer"});
    Display._slides = {};
  });

  it("should add a new slide", function () {
    var verse = "v1",
        text = "Amazing grace,\nhow sweet the sound",
        footer = "Public Domain";
    spyOn(Display, "reinit");

    Display.addTextSlide(verse, text, footer);

    expect(Display._slides[verse]).toEqual(0);
    expect($(".slides > section").length).toEqual(1);
    expect($(".slides > section")[0].innerHTML).toEqual(_prepareText(text));
    expect(Display.reinit).toHaveBeenCalled();
  });

  it("should add a new slide without calling reinit()", function () {
    var verse = "v1",
        text = "Amazing grace,\nhow sweet the sound",
        footer = "Public Domain";
    spyOn(Display, "reinit");

    Display.addTextSlide(verse, text, footer, false);

    expect(Display._slides[verse]).toEqual(0);
    expect($(".slides > section").length).toEqual(1);
    expect($(".slides > section")[0].innerHTML).toEqual(_prepareText(text));
    expect(Display.reinit).not.toHaveBeenCalled();
  });

  it("should update an existing slide", function () {
    var verse = "v1",
        text = "Amazing grace, how sweet the sound\nThat saved a wretch like me", 
        footer = "Public Domain";
    Display.addTextSlide(verse, "Amazing grace,\nhow sweet the sound", footer, false);
    spyOn(Display, "reinit");

    Display.addTextSlide(verse, text, true);

    expect(Display._slides[verse]).toEqual(0);
    expect($(".slides > section").length).toEqual(1);
    expect($(".slides > section")[0].innerHTML).toEqual(_prepareText(text));
    expect(Display.reinit).toHaveBeenCalled();
  });
});

describe("Display.setTextSlides", function () {
  beforeEach(function() {
    document.body.innerHTML = "";
    _createDiv({"class": "slides"});
    _createDiv({"class": "footer"});
    _createDiv({"id": "global-background"});
    Display._slides = {};
  });

  it("should add a list of slides", function () {
    var slides = [
      {
        "verse": "v1",
        "text": "Amazing grace, how sweet the sound\nThat saved a wretch like me\n" +
                "I once was lost, but now I'm found\nWas blind but now I see",
        "footer": "Public Domain"
      },
      {
        "verse": "v2",
        "text": "'twas Grace that taught, my heart to fear\nAnd grace, my fears relieved.\n" +
                "How precious did that grace appear,\nthe hour I first believed.",
        "footer": "Public Domain"
      }
    ];
    spyOn(Display, "clearSlides");
    spyOn(Display, "reinit");
    spyOn(Reveal, "slide");

    Display.setTextSlides(slides);

    expect(Display.clearSlides).toHaveBeenCalledTimes(1);
    expect(Display._slides["v1"]).toEqual(0);
    expect(Display._slides["v2"]).toEqual(1);
    expect($(".slides > section").length).toEqual(2);
    expect(Display.reinit).toHaveBeenCalledTimes(1);
    expect(Reveal.slide).toHaveBeenCalledWith(0);
  });

  xit("should correctly set outline width (skipped for now)", function () {
    const slides = [
      {
        "verse": "v1",
        "text": "Amazing grace, how sweet the sound\nThat saved a wretch like me\n" +
                "I once was lost, but now I'm found\nWas blind but now I see",
        "footer": "Public Domain"
      }
    ];
    const theme = {
      'font_main_color': 'yellow',
      'font_main_outline': true,
      'font_main_outline_size': 42,
      'font_main_outline_color': 'red'
    };
    spyOn(Display, "reinit");

    Display.setTextSlides(slides);
    Display.setTheme(theme);

    const slidesDiv = $(".slides")[0];
    expect(slidesDiv.style['-webkit-text-stroke']).toEqual('42pt red');
    expect(slidesDiv.style['padding-left']).toEqual('84pt');
    expect(slidesDiv.style['-webkit-text-fill-color']).toEqual('yellow');
  })
});

describe("Display.setImageSlides", function () {
  beforeEach(function() {
    document.body.innerHTML = "";
    _createDiv({"class": "slides"});
    _createDiv({"class": "footer"});
    _createDiv({"id": "global-background"});
    Display._slides = {};
  });

  it("should add a list of images", function () {
    var slides = [{"path": "file:///openlp1.jpg"}, {"path": "file:///openlp2.jpg"}];
    spyOn(Display, "clearSlides");
    spyOn(Display, "reinit");

    Display.setImageSlides(slides);

    expect(Display.clearSlides).toHaveBeenCalledTimes(1);
    expect(Display._slides["0"]).toEqual(0);
    expect(Display._slides["1"]).toEqual(1);
    expect($(".slides > section").length).toEqual(2);
    expect($(".slides > section > img").length).toEqual(2);
    expect($(".slides > section > img")[0].getAttribute("src")).toEqual("file:///openlp1.jpg")
    expect($(".slides > section > img")[0].getAttribute("style")).toEqual("max-width: 100%; max-height: 100%; margin: 0; position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%);")
    expect($(".slides > section > img")[1].getAttribute("src")).toEqual("file:///openlp2.jpg")
    expect($(".slides > section > img")[1].getAttribute("style")).toEqual("max-width: 100%; max-height: 100%; margin: 0; position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%);")
    expect(Display.reinit).toHaveBeenCalledTimes(1);
  });
});

describe("Display.setVideo", function () {
  beforeEach(function() {
    document.body.innerHTML = "";
    _createDiv({"class": "slides"});
    _createDiv({"id": "global-background"});
    Display._slides = {};
  });

  it("should add a video to the page", function () {
    var video = {"path": "file:///video.mp4"};
    spyOn(Display, "clearSlides");
    spyOn(Display, "reinit");

    Display.setVideo(video);

    expect(Display.clearSlides).toHaveBeenCalledTimes(1);
    expect($(".slides > section").length).toEqual(1);
    expect($(".slides > section > video").length).toEqual(1);
    expect($(".slides > section > video")[0].src).toEqual("file:///video.mp4")
    expect(Display.reinit).toHaveBeenCalledTimes(1);
  });
});

describe("Display.playVideo", function () {
  var playCalled = false,
      mockVideo = {
        play: function () {
          playCalled = true;
        }
      };

  beforeEach(function () {
    spyOn(window, "$").and.returnValue([mockVideo]);
  });

  it("should play the video when called", function () {
    Display.playVideo();
    expect(playCalled).toEqual(true);
  });
});

describe("Display.pauseVideo", function () {
  var pauseCalled = false,
      mockVideo = {
        pause: function () {
          pauseCalled = true;
        }
      };

  beforeEach(function () {
    spyOn(window, "$").and.returnValue([mockVideo]);
  });

  it("should pause the video when called", function () {
    Display.pauseVideo();
    expect(pauseCalled).toEqual(true);
  });
});

describe("Display.stopVideo", function () {
  var pauseCalled = false,
      mockVideo = {
        pause: function () {
          pauseCalled = true;
        },
        currentTime: 10.0
      };

  beforeEach(function () {
    spyOn(window, "$").and.returnValue([mockVideo]);
  });

  it("should play the video when called", function () {
    Display.stopVideo();
    expect(pauseCalled).toEqual(true);
    expect(mockVideo.currentTime).toEqual(0.0);
  });
});

describe("Display.seekVideo", function () {
  var mockVideo = {
        currentTime: 1.0
      };

  beforeEach(function () {
    spyOn(window, "$").and.returnValue([mockVideo]);
  });

  it("should seek to the specified position within the video when called", function () {
    Display.seekVideo(7.34);
    expect(mockVideo.currentTime).toEqual(7.34);
  });
});

describe("Display.setPlaybackRate", function () {
  var mockVideo = {
        playbackRate: 1.0
      };

  beforeEach(function () {
    spyOn(window, "$").and.returnValue([mockVideo]);
  });

  it("should set the playback rate of the video when called", function () {
    // Let's sound like chipmunks!
    Display.setPlaybackRate(1.25);
    expect(mockVideo.playbackRate).toEqual(1.25);
  });
});

describe("Display.setVideoVolume", function () {
  var mockVideo = {
        volume: 1.0
      };

  beforeEach(function () {
    spyOn(window, "$").and.returnValue([mockVideo]);
  });

  it("should set the correct volume of the video when called", function () {
    // Make it quiet
    Display.setVideoVolume(30);
    expect(mockVideo.volume).toEqual(0.3);
  });
});

describe("Display.toggleVideoMute", function () {
  var mockVideo = {
        muted: false
      };

  beforeEach(function () {
    spyOn(window, "$").and.returnValue([mockVideo]);
  });

  it("should mute the video when called", function () {
    mockVideo.muted = false;
    Display.toggleVideoMute();
    expect(mockVideo.muted).toEqual(true);
  });

  it("should unmute the video when called", function () {
    mockVideo.muted = true;
    Display.toggleVideoMute();
    expect(mockVideo.muted).toEqual(false);
  });
});

describe("AudioPlayer", function () {
  var audioPlayer, audioElement;

  beforeEach(function () {
    audioElement = {
      _eventListeners: {},
      _playing: false,
      _paused: false,
      _stopped: false,
      src: "",
      addEventListener: function (eventType, listener) {
        this._eventListeners[eventType] = this._eventListeners[eventType] || [];
        this._eventListeners[eventType].push(listener);
      },
      play: function () {
        this._playing = true;
        this._paused = false;
        this._stopped = false;
      },
      pause: function () {
        this._playing = false;
        this._paused = true;
        this._stopped = false;
      }
    };
    spyOn(document, "createElement").and.returnValue(audioElement);
    audioPlayer = new AudioPlayer();
  });

  it("should create an object", function () {
    expect(audioPlayer).toBeDefined();
    expect(audioPlayer._audioElement).not.toBeNull();
    expect(audioPlayer._eventListeners).toEqual({});
    expect(audioPlayer._playlist).toEqual([]);
    expect(audioPlayer._currentTrack).toEqual(null);
    expect(audioPlayer._canRepeat).toEqual(false);
    expect(audioPlayer._state).toEqual(AudioState.Stopped);
  });

  it("should call the correct method when _callListener is called", function () {
    var testCalled = false;
    function test(event) {
      testCalled = true;
    }
    audioPlayer._eventListeners["test"] = [test];
    audioPlayer._callListener({"type": "test"});
    expect(testCalled).toEqual(true);
  });

  it("should log a warning when _callListener is called for an unknown event", function () {
    spyOn(console, "warn");
    audioPlayer._callListener({"type": "test"});
    expect(console.warn).toHaveBeenCalledWith("Received unknown event \"test\", doing nothing.");
  });

  it("should add all the correct event listeners", function () {
    expectedListeners = {
      "ended": [audioPlayer.onEnded, audioPlayer._callListener],
      "timeupdate": [audioPlayer._callListener],
      "volumechange": [audioPlayer._callListener],
      "durationchange": [audioPlayer._callListener],
      "loadeddata": [audioPlayer._callListener]
    };
    expect(audioElement._eventListeners).toEqual(expectedListeners);
  });

  it("should add the correct event listener when calling addEventListener", function () {
    function dummy () {};
    var expectedListeners = {
      "test": [dummy]
    };
    audioPlayer.addEventListener("test", dummy);
    expect(audioPlayer._eventListeners).toEqual(expectedListeners);
  });

  it("should set call nextTrack when the onEnded listener is called", function () {
    spyOn(audioPlayer, "nextTrack");
    audioPlayer.onEnded({});
    expect(audioPlayer.nextTrack).toHaveBeenCalled();
  });

  it("should set the _canRepeat property when calling setCanRepeat", function () {
    audioPlayer.setCanRepeat(true);
    expect(audioPlayer._canRepeat).toEqual(true);
  });

  it("should clear the playlist when clearTracks is called", function () {
    audioPlayer._playlist = ["one", "two", "three"];
    audioPlayer.clearTracks();
    expect(audioPlayer._playlist).toEqual([]);
  });

  it("should add a track to the playlist when addTrack is called", function () {
    audioPlayer._playlist = [];
    audioPlayer.addTrack("one");
    expect(audioPlayer._playlist).toEqual(["one"]);
  });

  it("should move to the first track when canRepeat is true and nextTrack is called", function () {
    spyOn(audioPlayer, "play");
    audioPlayer.addTrack("one");
    audioPlayer.addTrack("two");
    audioPlayer.setCanRepeat(true);
    audioPlayer._currentTrack = "two";

    audioPlayer.nextTrack();

    expect(audioPlayer.play).toHaveBeenCalledWith("one");
  });

  it("should move to the next track when nextTrack is called", function () {
    spyOn(audioPlayer, "play");
    audioPlayer.addTrack("one");
    audioPlayer.addTrack("two");
    audioPlayer._currentTrack = "one";

    audioPlayer.nextTrack();

    expect(audioPlayer.play).toHaveBeenCalledWith("two");
  });

  it("should stop when canRepeat is false and nextTrack is called on the last track in the list", function () {
    spyOn(audioPlayer, "play");
    spyOn(audioPlayer, "stop");
    audioPlayer.addTrack("one");
    audioPlayer.addTrack("two");
    audioPlayer.setCanRepeat(false);
    audioPlayer._currentTrack = "two";

    audioPlayer.nextTrack();

    expect(audioPlayer.play).not.toHaveBeenCalled();
    expect(audioPlayer.stop).toHaveBeenCalled();
  });

  it("should play the first track when nextTrack is called when no songs are playing", function () {
    spyOn(audioPlayer, "play");
    audioPlayer.addTrack("one");
    audioPlayer.nextTrack();
    expect(audioPlayer.play).toHaveBeenCalledWith("one");
  });

  it("should log a warning when nextTrack is called when no songs are in the playlist", function () {
    spyOn(console, "warn");
    audioPlayer.nextTrack();
    expect(console.warn).toHaveBeenCalledWith("No tracks in playlist, doing nothing.");
  });

  it("should play the track specified when play is called with a filename", function () {
    audioPlayer.addTrack("one");
    audioPlayer.play("one");

    expect(audioPlayer._currentTrack).toEqual("one");
    expect(audioElement._playing).toEqual(true);
    expect(audioElement.src).toEqual("one");
    expect(audioPlayer._state).toEqual(AudioState.Playing);
  });

  it("should continue playing when play is called without a filename and the player is paused", function () {
    audioPlayer._state = AudioState.Paused;
    audioPlayer.play();

    expect(audioElement._playing).toEqual(true);
    expect(audioPlayer._state).toEqual(AudioState.Playing);
  });

  it("should do nothing when play is called without a filename and the player is not paused", function () {
    spyOn(console, "warn");
    audioPlayer._state = AudioState.Playing;
    audioPlayer.play();

    expect(console.warn).toHaveBeenCalledWith("No track currently paused and no track specified, doing nothing.");
  });

  it("should pause the current track when pause is called", function () {
    audioPlayer.pause();
    expect(audioPlayer._state).toEqual(AudioState.Paused);
    expect(audioElement._paused).toEqual(true);
  });

  it("should stop the current track when stop is called", function () {
    audioPlayer.stop();
    expect(audioPlayer._state).toEqual(AudioState.Stopped);
    expect(audioElement._paused).toEqual(true);
    expect(audioElement.src).toEqual("");
  });
});