dom/media/webvtt/TextTrack.cpp

   1 /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim:set ts=2 sw=2 et tw=78: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #include "mozilla/dom/TextTrack.h"
   8
   9 #include "mozilla/AsyncEventDispatcher.h"
  10 #include "mozilla/dom/HTMLMediaElement.h"
  11 #include "mozilla/dom/HTMLTrackElement.h"
  12 #include "mozilla/dom/TextTrackBinding.h"
  13 #include "mozilla/dom/TextTrackCue.h"
  14 #include "mozilla/dom/TextTrackCueList.h"
  15 #include "mozilla/dom/TextTrackList.h"
  16 #include "mozilla/dom/TextTrackRegion.h"
  17 #include "nsGlobalWindowInner.h"
  18
  19 extern mozilla::LazyLogModule gTextTrackLog;
  20
  21 #define WEBVTT_LOG(msg, ...)              \
  22   MOZ_LOG(gTextTrackLog, LogLevel::Debug, \
  23           ("TextTrack=%p, " msg, this, ##__VA_ARGS__))
  24
  25 namespace mozilla::dom {
  26
  27 NS_IMPL_CYCLE_COLLECTION_INHERITED(TextTrack, DOMEventTargetHelper, mCueList,
  28                                    mActiveCueList, mTextTrackList,
  29                                    mTrackElement)
  30
  31 NS_IMPL_ADDREF_INHERITED(TextTrack, DOMEventTargetHelper)
  32 NS_IMPL_RELEASE_INHERITED(TextTrack, DOMEventTargetHelper)
  33 NS_INTERFACE_MAP_BEGIN_CYCLE_COLLECTION(TextTrack)
  34 NS_INTERFACE_MAP_END_INHERITING(DOMEventTargetHelper)
  35
  36 TextTrack::TextTrack(nsPIDOMWindowInner* aOwnerWindow, TextTrackKind aKind,
  37                      const nsAString& aLabel, const nsAString& aLanguage,
  38                      TextTrackMode aMode, TextTrackReadyState aReadyState,
  39                      TextTrackSource aTextTrackSource)
  40     : DOMEventTargetHelper(aOwnerWindow),
  41       mKind(aKind),
  42       mLabel(aLabel),
  43       mLanguage(aLanguage),
  44       mMode(aMode),
  45       mReadyState(aReadyState),
  46       mTextTrackSource(aTextTrackSource) {
  47   SetDefaultSettings();
  48 }
  49
  50 TextTrack::TextTrack(nsPIDOMWindowInner* aOwnerWindow,
  51                      TextTrackList* aTextTrackList, TextTrackKind aKind,
  52                      const nsAString& aLabel, const nsAString& aLanguage,
  53                      TextTrackMode aMode, TextTrackReadyState aReadyState,
  54                      TextTrackSource aTextTrackSource)
  55     : DOMEventTargetHelper(aOwnerWindow),
  56       mTextTrackList(aTextTrackList),
  57       mKind(aKind),
  58       mLabel(aLabel),
  59       mLanguage(aLanguage),
  60       mMode(aMode),
  61       mReadyState(aReadyState),
  62       mTextTrackSource(aTextTrackSource) {
  63   SetDefaultSettings();
  64 }
  65
  66 TextTrack::~TextTrack() = default;
  67
  68 void TextTrack::SetDefaultSettings() {
  69   nsPIDOMWindowInner* ownerWindow = GetOwnerWindow();
  70   mCueList = new TextTrackCueList(ownerWindow);
  71   mActiveCueList = new TextTrackCueList(ownerWindow);
  72   mCuePos = 0;
  73   mDirty = false;
  74 }
  75
  76 JSObject* TextTrack::WrapObject(JSContext* aCx,
  77                                 JS::Handle<JSObject*> aGivenProto) {
  78   return TextTrack_Binding::Wrap(aCx, this, aGivenProto);
  79 }
  80
  81 void TextTrack::SetMode(TextTrackMode aValue) {
  82   if (mMode == aValue) {
  83     return;
  84   }
  85   WEBVTT_LOG("Set mode=%s for track kind %s", GetEnumString(aValue).get(),
  86              GetEnumString(mKind).get());
  87   mMode = aValue;
  88
  89   HTMLMediaElement* mediaElement = GetMediaElement();
  90   if (aValue == TextTrackMode::Disabled) {
  91     for (size_t i = 0; i < mCueList->Length() && mediaElement; ++i) {
  92       mediaElement->NotifyCueRemoved(*(*mCueList)[i]);
  93     }
  94     SetCuesInactive();
  95   } else {
  96     for (size_t i = 0; i < mCueList->Length() && mediaElement; ++i) {
  97       mediaElement->NotifyCueAdded(*(*mCueList)[i]);
  98     }
  99   }
 100   if (mediaElement) {
 101     mediaElement->NotifyTextTrackModeChanged();
 102   }
 103   // https://html.spec.whatwg.org/multipage/media.html#sourcing-out-of-band-text-tracks:start-the-track-processing-model
 104   // Run the `start-the-track-processing-model` to track's corresponding track
 105   // element whenever track's mode changes.
 106   if (mTrackElement) {
 107     mTrackElement->MaybeDispatchLoadResource();
 108   }
 109   // Ensure the TimeMarchesOn is called in case that the mCueList
 110   // is empty.
 111   NotifyCueUpdated(nullptr);
 112 }
 113
 114 void TextTrack::GetId(nsAString& aId) const {
 115   // If the track has a track element then its id should be the same as the
 116   // track element's id.
 117   if (mTrackElement) {
 118     mTrackElement->GetAttr(nsGkAtoms::id, aId);
 119   }
 120 }
 121
 122 void TextTrack::AddCue(TextTrackCue& aCue) {
 123   WEBVTT_LOG("AddCue %p [%f:%f]", &aCue, aCue.StartTime(), aCue.EndTime());
 124   TextTrack* oldTextTrack = aCue.GetTrack();
 125   if (oldTextTrack) {
 126     ErrorResult dummy;
 127     oldTextTrack->RemoveCue(aCue, dummy);
 128   }
 129   mCueList->AddCue(aCue);
 130   aCue.SetTrack(this);
 131   HTMLMediaElement* mediaElement = GetMediaElement();
 132   if (mediaElement && (mMode != TextTrackMode::Disabled)) {
 133     mediaElement->NotifyCueAdded(aCue);
 134   }
 135 }
 136
 137 void TextTrack::RemoveCue(TextTrackCue& aCue, ErrorResult& aRv) {
 138   WEBVTT_LOG("RemoveCue %p", &aCue);
 139   // Bug1304948, check the aCue belongs to the TextTrack.
 140   mCueList->RemoveCue(aCue, aRv);
 141   if (aRv.Failed()) {
 142     return;
 143   }
 144   aCue.SetActive(false);
 145   aCue.SetTrack(nullptr);
 146   HTMLMediaElement* mediaElement = GetMediaElement();
 147   if (mediaElement) {
 148     mediaElement->NotifyCueRemoved(aCue);
 149   }
 150 }
 151
 152 void TextTrack::ClearAllCues() {
 153   WEBVTT_LOG("ClearAllCues");
 154   ErrorResult dummy;
 155   while (!mCueList->IsEmpty()) {
 156     RemoveCue(*(*mCueList)[0], dummy);
 157   }
 158 }
 159
 160 void TextTrack::SetCuesDirty() {
 161   for (uint32_t i = 0; i < mCueList->Length(); i++) {
 162     ((*mCueList)[i])->Reset();
 163   }
 164 }
 165
 166 TextTrackCueList* TextTrack::GetActiveCues() {
 167   if (mMode != TextTrackMode::Disabled) {
 168     return mActiveCueList;
 169   }
 170   return nullptr;
 171 }
 172
 173 void TextTrack::GetActiveCueArray(nsTArray<RefPtr<TextTrackCue> >& aCues) {
 174   if (mMode != TextTrackMode::Disabled) {
 175     mActiveCueList->GetArray(aCues);
 176   }
 177 }
 178
 179 TextTrackReadyState TextTrack::ReadyState() const { return mReadyState; }
 180
 181 void TextTrack::SetReadyState(TextTrackReadyState aState) {
 182   WEBVTT_LOG("SetReadyState=%s", EnumValueToString(aState));
 183   mReadyState = aState;
 184   HTMLMediaElement* mediaElement = GetMediaElement();
 185   if (mediaElement && (mReadyState == TextTrackReadyState::Loaded ||
 186                        mReadyState == TextTrackReadyState::FailedToLoad)) {
 187     mediaElement->RemoveTextTrack(this, true);
 188     mediaElement->UpdateReadyState();
 189   }
 190 }
 191
 192 TextTrackList* TextTrack::GetTextTrackList() { return mTextTrackList; }
 193
 194 void TextTrack::SetTextTrackList(TextTrackList* aTextTrackList) {
 195   mTextTrackList = aTextTrackList;
 196 }
 197
 198 HTMLTrackElement* TextTrack::GetTrackElement() { return mTrackElement; }
 199
 200 void TextTrack::SetTrackElement(HTMLTrackElement* aTrackElement) {
 201   mTrackElement = aTrackElement;
 202 }
 203
 204 void TextTrack::SetCuesInactive() {
 205   WEBVTT_LOG("SetCuesInactive");
 206   mCueList->SetCuesInactive();
 207 }
 208
 209 void TextTrack::NotifyCueUpdated(TextTrackCue* aCue) {
 210   WEBVTT_LOG("NotifyCueUpdated, cue=%p", aCue);
 211   mCueList->NotifyCueUpdated(aCue);
 212   HTMLMediaElement* mediaElement = GetMediaElement();
 213   if (mediaElement) {
 214     mediaElement->NotifyCueUpdated(aCue);
 215   }
 216 }
 217
 218 void TextTrack::GetLabel(nsAString& aLabel) const {
 219   if (mTrackElement) {
 220     mTrackElement->GetLabel(aLabel);
 221   } else {
 222     aLabel = mLabel;
 223   }
 224 }
 225 void TextTrack::GetLanguage(nsAString& aLanguage) const {
 226   if (mTrackElement) {
 227     mTrackElement->GetSrclang(aLanguage);
 228   } else {
 229     aLanguage = mLanguage;
 230   }
 231 }
 232
 233 void TextTrack::DispatchAsyncTrustedEvent(const nsString& aEventName) {
 234   nsGlobalWindowInner* win = GetOwnerWindow();
 235   if (!win) {
 236     return;
 237   }
 238   win->Dispatch(
 239       NS_NewRunnableFunction("dom::TextTrack::DispatchAsyncTrustedEvent",
 240                              [self = RefPtr{this}, aEventName]() {
 241                                self->DispatchTrustedEvent(aEventName);
 242                              }));
 243 }
 244
 245 bool TextTrack::IsLoaded() {
 246   if (mMode == TextTrackMode::Disabled) {
 247     return true;
 248   }
 249   // If the TrackElement's src is null, we can not block the
 250   // MediaElement.
 251   if (mTrackElement) {
 252     nsAutoString src;
 253     if (!(mTrackElement->GetAttr(nsGkAtoms::src, src))) {
 254       return true;
 255     }
 256   }
 257   return mReadyState >= TextTrackReadyState::Loaded;
 258 }
 259
 260 void TextTrack::NotifyCueActiveStateChanged(TextTrackCue* aCue) {
 261   MOZ_ASSERT(aCue);
 262   if (aCue->GetActive()) {
 263     MOZ_ASSERT(!mActiveCueList->IsCueExist(aCue));
 264     WEBVTT_LOG("NotifyCueActiveStateChanged, add cue %p to the active list",
 265                aCue);
 266     mActiveCueList->AddCue(*aCue);
 267   } else {
 268     MOZ_ASSERT(mActiveCueList->IsCueExist(aCue));
 269     WEBVTT_LOG(
 270         "NotifyCueActiveStateChanged, remove cue %p from the active list",
 271         aCue);
 272     mActiveCueList->RemoveCue(*aCue);
 273   }
 274 }
 275
 276 void TextTrack::GetCurrentCuesAndOtherCues(
 277     RefPtr<TextTrackCueList>& aCurrentCues,
 278     RefPtr<TextTrackCueList>& aOtherCues,
 279     const media::TimeInterval& aInterval) const {
 280   const HTMLMediaElement* mediaElement = GetMediaElement();
 281   if (!mediaElement) {
 282     return;
 283   }
 284
 285   if (Mode() == TextTrackMode::Disabled) {
 286     return;
 287   }
 288
 289   // According to `time marches on` step1, current cue list contains the cues
 290   // whose start times are less than or equal to the current playback position
 291   // and whose end times are greater than the current playback position.
 292   // https://html.spec.whatwg.org/multipage/media.html#time-marches-on
 293   MOZ_ASSERT(aCurrentCues && aOtherCues);
 294   const double playbackTime = mediaElement->CurrentTime();
 295   for (uint32_t idx = 0; idx < mCueList->Length(); idx++) {
 296     TextTrackCue* cue = (*mCueList)[idx];
 297     WEBVTT_LOG("cue %p [%f:%f], playbackTime=%f", cue, cue->StartTime(),
 298                cue->EndTime(), playbackTime);
 299     if (cue->StartTime() <= playbackTime && cue->EndTime() > playbackTime) {
 300       WEBVTT_LOG("Add cue %p [%f:%f] to current cue list", cue,
 301                  cue->StartTime(), cue->EndTime());
 302       aCurrentCues->AddCue(*cue);
 303     } else {
 304       // As the spec didn't have a restriction for the negative duration, it
 305       // does happen sometime if user sets it explicitly. It would be treated as
 306       // a `missing cue` later in the `TimeMarchesOn` but it won't be displayed.
 307       if (cue->EndTime() < cue->StartTime()) {
 308         // Add cue into `otherCue` only when its start time is contained by the
 309         // current time interval.
 310         if (aInterval.Contains(
 311                 media::TimeUnit::FromSeconds(cue->StartTime()))) {
 312           WEBVTT_LOG("[Negative duration] Add cue %p [%f:%f] to other cue list",
 313                      cue, cue->StartTime(), cue->EndTime());
 314           aOtherCues->AddCue(*cue);
 315         }
 316         continue;
 317       }
 318       media::TimeInterval cueInterval(
 319           media::TimeUnit::FromSeconds(cue->StartTime()),
 320           media::TimeUnit::FromSeconds(cue->EndTime()));
 321       // cues are completely outside the time interval.
 322       if (!aInterval.Touches(cueInterval)) {
 323         continue;
 324       }
 325       // contains any cues which are overlapping within the time interval.
 326       WEBVTT_LOG("Add cue %p [%f:%f] to other cue list", cue, cue->StartTime(),
 327                  cue->EndTime());
 328       aOtherCues->AddCue(*cue);
 329     }
 330   }
 331 }
 332
 333 HTMLMediaElement* TextTrack::GetMediaElement() const {
 334   return mTextTrackList ? mTextTrackList->GetMediaElement() : nullptr;
 335 }
 336
 337 }  // namespace mozilla::dom