gecko/content/media/TextTrackCue.h

355 lines
8.2 KiB
C++

/* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim:set ts=2 sw=2 et tw=78: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef mozilla_dom_TextTrackCue_h
#define mozilla_dom_TextTrackCue_h
#include "mozilla/dom/DocumentFragment.h"
#include "mozilla/dom/TextTrack.h"
#include "mozilla/dom/TextTrackCueBinding.h"
#include "nsCycleCollectionParticipant.h"
#include "nsDOMEventTargetHelper.h"
struct webvtt_node;
namespace mozilla {
namespace dom {
class HTMLTrackElement;
class TextTrack;
class TextTrackCue MOZ_FINAL : public nsDOMEventTargetHelper
{
public:
NS_DECL_ISUPPORTS_INHERITED
NS_DECL_CYCLE_COLLECTION_SCRIPT_HOLDER_CLASS_INHERITED(TextTrackCue,
nsDOMEventTargetHelper)
// TextTrackCue WebIDL
// See bug 868509 about splitting out the WebVTT-specific interfaces.
static already_AddRefed<TextTrackCue>
Constructor(GlobalObject& aGlobal,
double aStartTime,
double aEndTime,
const nsAString& aText,
ErrorResult& aRv)
{
nsRefPtr<TextTrackCue> ttcue = new TextTrackCue(aGlobal.Get(), aStartTime,
aEndTime, aText);
return ttcue.forget();
}
TextTrackCue(nsISupports* aGlobal, double aStartTime, double aEndTime,
const nsAString& aText);
TextTrackCue(nsISupports* aGlobal, double aStartTime, double aEndTime,
const nsAString& aText, HTMLTrackElement* aTrackElement,
webvtt_node* head);
~TextTrackCue();
virtual JSObject* WrapObject(JSContext* aCx,
JS::Handle<JSObject*> aScope) MOZ_OVERRIDE;
nsISupports* GetParentObject()
{
return mGlobal;
}
TextTrack* GetTrack() const
{
return mTrack;
}
void GetId(nsAString& aId) const
{
aId = mId;
}
void SetId(const nsAString& aId)
{
if (mId == aId) {
return;
}
mId = aId;
CueChanged();
}
double StartTime() const
{
return mStartTime;
}
void SetStartTime(double aStartTime)
{
//XXXhumph: validate? bug 868519.
if (mStartTime == aStartTime)
return;
mStartTime = aStartTime;
CueChanged();
}
double EndTime() const
{
return mEndTime;
}
void SetEndTime(double aEndTime)
{
//XXXhumph: validate? bug 868519.
if (mEndTime == aEndTime)
return;
mEndTime = aEndTime;
CueChanged();
}
bool PauseOnExit()
{
return mPauseOnExit;
}
void SetPauseOnExit(bool aPauseOnExit)
{
if (mPauseOnExit == aPauseOnExit)
return;
mPauseOnExit = aPauseOnExit;
CueChanged();
}
void GetVertical(nsAString& aVertical)
{
aVertical = mVertical;
}
void SetVertical(const nsAString& aVertical)
{
if (mVertical == aVertical)
return;
mReset = true;
mVertical = aVertical;
CueChanged();
}
bool SnapToLines()
{
return mSnapToLines;
}
void SetSnapToLines(bool aSnapToLines)
{
if (mSnapToLines == aSnapToLines)
return;
mReset = true;
mSnapToLines = aSnapToLines;
CueChanged();
}
double Line() const
{
return mLine;
}
void SetLine(double aLine)
{
//XXX: validate? bug 868519.
mReset = true;
mLine = aLine;
}
int32_t Position() const
{
return mPosition;
}
void SetPosition(int32_t aPosition)
{
// XXXhumph: validate? bug 868519.
if (mPosition == aPosition)
return;
mReset = true;
mPosition = aPosition;
CueChanged();
}
int32_t Size() const
{
return mSize;
}
void SetSize(int32_t aSize)
{
if (mSize == aSize) {
return;
}
if (aSize < 0 || aSize > 100) {
//XXX:throw IndexSizeError; bug 868519.
}
mReset = true;
mSize = aSize;
CueChanged();
}
TextTrackCueAlign Align() const
{
return mAlign;
}
void SetAlign(TextTrackCueAlign& aAlign)
{
if (mAlign == aAlign)
return;
mReset = true;
mAlign = aAlign;
CueChanged();
}
void GetText(nsAString& aText) const
{
aText = mText;
}
void SetText(const nsAString& aText)
{
// XXXhumph: validate? bug 868519.
if (mText == aText)
return;
mReset = true;
mText = aText;
CueChanged();
}
already_AddRefed<DocumentFragment> GetCueAsHTML() const
{
// XXXhumph: todo. Bug 868509.
return nullptr;
}
IMPL_EVENT_HANDLER(enter)
IMPL_EVENT_HANDLER(exit)
// Helper functions for implementation.
bool
operator==(const TextTrackCue& rhs) const
{
return mId.Equals(rhs.mId);
}
const nsAString& Id() const
{
return mId;
}
/**
* Overview of WEBVTT cuetext and anonymous content setup.
*
* webvtt_nodes are the parsed version of WEBVTT cuetext. WEBVTT cuetext is
* the portion of a WEBVTT cue that specifies what the caption will actually
* show up as on screen.
*
* WEBVTT cuetext can contain markup that loosely relates to HTML markup. It
* can contain tags like <b>, <u>, <i>, <c>, <v>, <ruby>, <rt>, <lang>,
* including timestamp tags.
*
* When the caption is ready to be displayed the webvtt_nodes are converted
* over to anonymous DOM content. <i>, <u>, <b>, <ruby>, and <rt> all become
* HTMLElements of their corresponding HTML markup tags. <c> and <v> are
* converted to <span> tags. Timestamp tags are converted to XML processing
* instructions. Additionally, all cuetext tags support specifying of classes.
* This takes the form of <foo.class.subclass>. These classes are then parsed
* and set as the anonymous content's class attribute.
*
* Rules on constructing DOM objects from webvtt_nodes can be found here
* http://dev.w3.org/html5/webvtt/#webvtt-cue-text-dom-construction-rules.
* Current rules are taken from revision on April 15, 2013.
*/
/**
* Converts the TextTrackCue's cuetext into a tree of DOM objects and attaches
* it to a div on it's owning TrackElement's MediaElement's caption overlay.
*/
void RenderCue();
/**
* Produces a tree of anonymous content based on the tree of the processed
* cue text. This lives in a tree of C nodes whose head is mHead.
*
* Returns a DocumentFragment that is the head of the tree of anonymous
* content.
*/
already_AddRefed<DocumentFragment> GetCueAsHTML();
/**
* Converts mHead to a list of DOM elements and attaches it to aParentContent.
*
* Processes the C node tree in a depth-first pre-order traversal and creates
* a mirrored DOM tree. The conversion rules come from the webvtt DOM
* construction rules:
* http://dev.w3.org/html5/webvtt/#webvtt-cue-text-dom-construction-rules
* Current rules taken from revision on May 13, 2013.
*/
void
ConvertNodeTreeToDOMTree(nsIContent* aParentContent);
/**
* Converts an internal webvtt node, i.e. one that has children, to an
* anonymous HTMLElement.
*/
already_AddRefed<nsIContent>
ConvertInternalNodeToContent(const webvtt_node* aWebVTTNode);
/**
* Converts a leaf webvtt node, i.e. one that does not have children, to
* either a text node or processing instruction.
*/
already_AddRefed<nsIContent>
ConvertLeafNodeToContent(const webvtt_node* aWebVTTNode);
private:
void CueChanged();
void SetDefaultCueSettings();
void CreateCueOverlay();
nsCOMPtr<nsISupports> mGlobal;
nsString mText;
double mStartTime;
double mEndTime;
nsRefPtr<TextTrack> mTrack;
nsRefPtr<HTMLTrackElement> mTrackElement;
webvtt_node *mHead;
nsString mId;
int32_t mPosition;
int32_t mSize;
bool mPauseOnExit;
bool mSnapToLines;
nsString mVertical;
int mLine;
TextTrackCueAlign mAlign;
// Holds the computed DOM elements that represent the parsed cue text.
// http://www.whatwg.org/specs/web-apps/current-work/#text-track-cue-display-state
nsCOMPtr<nsIContent> mDisplayState;
// Tells whether or not we need to recompute mDisplayState. This is set
// anytime a property that relates to the display of the TextTrackCue is
// changed.
bool mReset;
};
} // namespace dom
} // namespace mozilla
#endif // mozilla_dom_TextTrackCue_h