Initial implementation of AudioTrack, AudioTrackList, VideoTrack, and VideoTrackList.

Source/core/html/HTMLMediaElement.cpp

Index: Source/core/html/HTMLMediaElement.cpp
diff --git a/Source/core/html/HTMLMediaElement.cpp b/Source/core/html/HTMLMediaElement.cpp
index 9ad6b79ad0a4cd28b8491c4090ebd0f33350abb0..2a38583edc84d997006621ecfbe72bf98d6aae7f 100644
--- a/Source/core/html/HTMLMediaElement.cpp
+++ b/Source/core/html/HTMLMediaElement.cpp
@@ -52,9 +52,13 @@
 #include "core/html/MediaFragmentURIParser.h"
 #include "core/html/TimeRanges.h"
 #include "core/html/shadow/MediaControls.h"
+#include "core/html/track/AudioTrack.h"
+#include "core/html/track/AudioTrackList.h"
 #include "core/html/track/InbandTextTrack.h"
 #include "core/html/track/TextTrackCueList.h"
 #include "core/html/track/TextTrackList.h"
+#include "core/html/track/VideoTrack.h"
+#include "core/html/track/VideoTrackList.h"
 #include "core/loader/FrameLoader.h"
 #include "core/rendering/RenderVideo.h"
 #include "core/rendering/RenderView.h"
@@ -85,6 +89,7 @@
 using namespace std;
 using blink::WebInbandTextTrack;
 using blink::WebMimeRegistry;
+using blink::WebMediaPlayerClient;
 
 namespace WebCore {
 
@@ -163,6 +168,52 @@ private:
     HTMLMediaElement* m_mediaElement;
 };
 
+static const AtomicString& VideoKindToString(WebMediaPlayerClient::VideoTrackKind kind)
+{
+    switch (kind) {
+    case WebMediaPlayerClient::VideoTrackKindNone:
+        return emptyAtom;
+    case WebMediaPlayerClient::VideoTrackKindAlternative:
+        return VideoTrack::alternativeKeyword();
+    case WebMediaPlayerClient::VideoTrackKindCaptions:
+        return VideoTrack::captionsKeyword();
+    case WebMediaPlayerClient::VideoTrackKindMain:
+        return VideoTrack::mainKeyword();
+    case WebMediaPlayerClient::VideoTrackKindSign:
+        return VideoTrack::signKeyword();
+    case WebMediaPlayerClient::VideoTrackKindSubtitles:
+        return VideoTrack::subtitlesKeyword();
+    case WebMediaPlayerClient::VideoTrackKindCommentary:
+        return VideoTrack::commentaryKeyword();
+    }
+
+    ASSERT_NOT_REACHED();
+    return emptyAtom;
+}
+
+static const AtomicString& AudioKindToString(WebMediaPlayerClient::AudioTrackKind kind)
+{
+    switch (kind) {
+    case WebMediaPlayerClient::AudioTrackKindNone:
+        return emptyAtom;
+    case WebMediaPlayerClient::AudioTrackKindAlternative:
+        return AudioTrack::alternativeKeyword();
+    case WebMediaPlayerClient::AudioTrackKindDescriptions:
+        return AudioTrack::descriptionsKeyword();
+    case WebMediaPlayerClient::AudioTrackKindMain:
+        return AudioTrack::mainKeyword();
+    case WebMediaPlayerClient::AudioTrackKindMainDescriptions:
+        return AudioTrack::mainDescriptionsKeyword();
+    case WebMediaPlayerClient::AudioTrackKindTranslation:
+        return AudioTrack::translationKeyword();
+    case WebMediaPlayerClient::AudioTrackKindCommentary:
+        return AudioTrack::commentaryKeyword();
+    }
+
+    ASSERT_NOT_REACHED();
+    return emptyAtom;
+}
+
 static bool canLoadURL(const KURL& url, const ContentType& contentType, const String& keySystem)
 {
     DEFINE_STATIC_LOCAL(const String, codecs, ("codecs"));
@@ -309,6 +360,12 @@ HTMLMediaElement::~HTMLMediaElement()
     if (m_textTracks)
         m_textTracks->clearOwner();
 
+    if (m_audioTracks)
+        m_audioTracks->shutdown();
+
+    if (m_videoTracks)
+        m_videoTracks->shutdown();
+
     if (m_mediaController) {
         m_mediaController->removeMediaElement(this);
         m_mediaController = nullptr;
@@ -368,6 +425,15 @@ void HTMLMediaElement::didMoveToNewDocument(Document& oldDocument)
     oldDocument.decrementLoadEventDelayCount();
 
     ActiveDOMObject::didMoveToNewExecutionContext(&document());
+
+    // Notify track lists so they don't stop firing events when moved to a new document
+    // and the original document gets destroyed.
+    if (m_audioTracks)
+        m_audioTracks->didMoveToNewExecutionContext(&document());
+
+    if (m_videoTracks)
+        m_videoTracks->didMoveToNewExecutionContext(&document());
+
     HTMLElement::didMoveToNewDocument(oldDocument);
 }
 
@@ -1566,7 +1632,12 @@ void HTMLMediaElement::setReadyState(MediaPlayer::ReadyState state)
     }
 
     if (m_readyState >= HAVE_METADATA && oldState < HAVE_METADATA) {
+        createPlaceholderTracksIfNecessary();
+
         prepareMediaFragmentURI();
+
+        selectInitialTracksIfNecessary();
+
         scheduleEvent(EventTypeNames::durationchange);
         if (isVideo())
             scheduleEvent(EventTypeNames::resize);
@@ -2189,6 +2260,116 @@ bool HTMLMediaElement::canPlay() const
     return paused() || ended() || m_readyState < HAVE_METADATA;
 }
 
+AudioTrackList& HTMLMediaElement::audioTracks()
+{
+    ASSERT(RuntimeEnabledFeatures::audioVideoTracksEnabled());
+
+    if (!m_audioTracks)
+        m_audioTracks = AudioTrackList::create(this);
+
+    return *m_audioTracks;
+}
+
+void HTMLMediaElement::audioTrackChanged(const AtomicString& audioTrackID, bool enabled)
+{
+    WTF_LOG(Media, "HTMLMediaElement::audioTrackChanged('%s', %d)", audioTrackID.ascii().data(), enabled);
+    ASSERT(RuntimeEnabledFeatures::audioVideoTracksEnabled());
+    ASSERT(!audioTrackID.isEmpty());
+
+    audioTracks().scheduleChangeEvent();
+
+    // FIXME: Add call on m_mediaSource to notify it of track changes once the SourceBuffer.audioTracks attribute is added.
+
+    if (webMediaPlayer())
+        webMediaPlayer()->enabledAudioTrackChange(audioTrackID, enabled);
+}
+
+VideoTrackList& HTMLMediaElement::videoTracks()
+{
+    ASSERT(RuntimeEnabledFeatures::audioVideoTracksEnabled());
+
+    if (!m_videoTracks)
+        m_videoTracks = VideoTrackList::create(this);
+
+    return *m_videoTracks;
+}
+
+void HTMLMediaElement::selectedVideoTrackChanged(const AtomicString& selectedTrackID)
+{
+    WTF_LOG(Media, "HTMLMediaElement::selectedVideoTrackChanged('%s')", selectedTrackID.ascii().data());
+    ASSERT(RuntimeEnabledFeatures::audioVideoTracksEnabled());
+
+    AtomicString unselectedTrackID;
+
+    int oldSelectedIndex = videoTracks().selectedIndex();
+    if (oldSelectedIndex != -1)
+        unselectedTrackID = videoTracks().anonymousIndexedGetter(oldSelectedIndex)->id();
+
+    ASSERT(unselectedTrackID != selectedTrackID);
+
+    videoTracks().trackSelected(selectedTrackID);
+
+    // FIXME: Add call on m_mediaSource to notify it of track changes once the SourceBuffer.videoTracks attribute is added.
+
+    ASSERT(!unselectedTrackID.isEmpty() || !selectedTrackID.isEmpty());
+
+    if (webMediaPlayer())
+        webMediaPlayer()->selectedVideoTrackChange(unselectedTrackID, selectedTrackID);
+}
+
+void HTMLMediaElement::addVideoTrack(const AtomicString& id, blink::WebMediaPlayerClient::VideoTrackKind kind, const AtomicString& label, const AtomicString& language, bool selected)
+{
+    AtomicString kindString = VideoKindToString(kind);
+    WTF_LOG(Media, "HTMLMediaElement::addVideoTrack('%s', '%s', '%s', '%s', %d)",
+        id.ascii().data(), kindString.ascii().data(), label.ascii().data(), language.ascii().data(), selected);
+    ASSERT(!id.isEmpty());
+
+    RefPtr<VideoTrack> videoTrack = VideoTrack::create(this, id, kindString, label, language);
+    videoTracks().add(videoTrack.get());
+
+    if (selected)
+        videoTrack->setSelected(true);
+}
+
+void HTMLMediaElement::removeVideoTrack(const AtomicString& id)
+{
+    WTF_LOG(Media, "HTMLMediaElement::removeVideoTrack('%s')", id.ascii().data());
+    ASSERT(!id.isEmpty());
+
+    if (!RuntimeEnabledFeatures::audioVideoTracksEnabled())
+        return;
+
+    videoTracks().remove(id);
+}
+
+void HTMLMediaElement::addAudioTrack(const AtomicString& id, blink::WebMediaPlayerClient::AudioTrackKind kind, const AtomicString& label, const AtomicString& language, bool enabled)
+{
+    AtomicString kindString = AudioKindToString(kind);
+    WTF_LOG(Media, "HTMLMediaElement::addAudioTrack('%s', '%s', '%s', '%s', %d)",
+        id.ascii().data(), kindString.ascii().data(), label.ascii().data(), language.ascii().data(), enabled);
+    ASSERT(!id.isEmpty());
+
+    if (!RuntimeEnabledFeatures::audioVideoTracksEnabled())
+        return;
+
+    RefPtr<AudioTrack> audioTrack = AudioTrack::create(this, id, kindString, label, language);
+    audioTracks().add(audioTrack.get());
+
+    if (enabled)
+        audioTrack->setEnabled(true);
+}
+
+void HTMLMediaElement::removeAudioTrack(const AtomicString& id)
+{
+    WTF_LOG(Media, "HTMLMediaElement::removeAudioTrack('%s')", id.ascii().data());
+    ASSERT(!id.isEmpty());
+
+    if (!RuntimeEnabledFeatures::audioVideoTracksEnabled())
+        return;
+
+    audioTracks().remove(id);
+}
+
 void HTMLMediaElement::mediaPlayerDidAddTextTrack(WebInbandTextTrack* webTrack)
 {
     if (!RuntimeEnabledFeatures::videoTrackEnabled())
@@ -2264,11 +2445,20 @@ void HTMLMediaElement::removeTextTrack(TextTrack* track)
 
 void HTMLMediaElement::forgetResourceSpecificTracks()
 {
+    // Implements the "forget the media element's media-resource-specific tracks" algorithm.
+    // The order is explicitly specified as text, then audio, and finally video. Also
+    // 'removetrack' events should not be fired.
     if (m_textTracks) {
         TrackDisplayUpdateScope scope(this);
         m_textTracks->removeAllInbandTracks();
         closeCaptionTracksChanged();
     }
+
+    if (m_audioTracks)
+        m_audioTracks->removeAll();
+
+    if (m_videoTracks)
+        m_videoTracks->removeAll();
 }
 
 PassRefPtr<TextTrack> HTMLMediaElement::addTextTrack(const AtomicString& kind, const AtomicString& label, const AtomicString& language, ExceptionState& exceptionState)
@@ -3580,6 +3770,8 @@ void HTMLMediaElement::prepareMediaFragmentURI()
     } else
         m_fragmentEndTime = MediaPlayer::invalidTime();
 
+    // FIXME: Add support for selecting tracks by ID with the Media Fragments track dimension.
+
     if (m_fragmentStartTime != MediaPlayer::invalidTime() && m_readyState < HAVE_FUTURE_DATA)
         prepareToPlay();
 }
@@ -3638,4 +3830,32 @@ bool HTMLMediaElement::isInteractiveContent() const
     return fastHasAttribute(controlsAttr);
 }
 
+void HTMLMediaElement::createPlaceholderTracksIfNecessary()
+{
+    if (!RuntimeEnabledFeatures::audioVideoTracksEnabled())
+        return;
+
+    // Create a placeholder audio track if |m_player| says it has audio but it didn't explicitly announce the tracks.
+    if (m_player->hasAudio() && !audioTracks().length())
+        addAudioTrack("audio", WebMediaPlayerClient::AudioTrackKindMain, "Audio Track", "", true);
+
+    // Create a placeholder video track if |m_player| says it has video but it didn't explicitly announce the tracks.
+    if (m_player->hasVideo() && !videoTracks().length())

[philipj_slow, 2014/03/14 03:51:59]

hasVideo() can only be true for HTMLVideoElement, but the spec's "If the media
resource is found to have a video track" steps don't discriminate between audio
and video elements. In other words, we need to test that audio elements work the
same as video elements as far as this is concerned. We could also file a spec
bug, but I'm not sure hiding video tracks for HTMLAudioElement would actually be
useful.

[acolwell GONE FROM CHROMIUM, 2014/03/18 22:02:15]

This is m_player->hasVideo() not hasVideo(). It reports the presence of video
tracks independent of whether this is an HTMLVideoElement or HTMLAudioElement.

[philipj_slow, 2014/03/20 16:17:40]

You're right.

+        addVideoTrack("video", WebMediaPlayerClient::VideoTrackKindMain, "Video Track", "", true);
+}
+
+void HTMLMediaElement::selectInitialTracksIfNecessary()
+{
+    if (!RuntimeEnabledFeatures::audioVideoTracksEnabled())
+        return;
+
+    // Enable the first audio track if an audio track hasn't been enabled yet.
+    if (audioTracks().length() > 0 && !audioTracks().hasEnabledTrack())
+        audioTracks().anonymousIndexedGetter(0)->setEnabled(true);
+
+    // Select the first video track if a video track hasn't been selected yet.
+    if (videoTracks().length() > 0 && videoTracks().selectedIndex() == -1)
+        videoTracks().anonymousIndexedGetter(0)->setSelected(true);
+}
+
 }