root/Source/modules/speech/SpeechSynthesis.cpp

DEFINITIONS

1. create
2. m_isPaused
3. setPlatformSynthesizer
4. executionContext
5. voicesDidChange
6. getVoices
7. speaking
8. pending
9. paused
10. startSpeakingImmediately
11. speak
12. cancel
13. pause
14. resume
15. fireEvent
16. handleSpeakingCompleted
17. boundaryEventOccurred
18. didStartSpeaking
19. didPauseSpeaking
20. didResumeSpeaking
21. didFinishSpeaking
22. speakingErrorOccurred
23. currentSpeechUtterance
24. interfaceName
25. trace

/*
 * Copyright (C) 2013 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE COMPUTER, INC. ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL APPLE COMPUTER, INC. OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "config.h"
#include "modules/speech/SpeechSynthesis.h"

#include "bindings/v8/ExceptionState.h"
#include "core/dom/ExecutionContext.h"
#include "modules/speech/SpeechSynthesisEvent.h"
#include "platform/speech/PlatformSpeechSynthesisVoice.h"
#include "wtf/CurrentTime.h"

namespace WebCore {

PassRefPtrWillBeRawPtr<SpeechSynthesis> SpeechSynthesis::create(ExecutionContext* context)
{
    return adoptRefWillBeRefCountedGarbageCollected(new SpeechSynthesis(context));
}

SpeechSynthesis::SpeechSynthesis(ExecutionContext* context)
    : ContextLifecycleObserver(context)
    , m_platformSpeechSynthesizer(PlatformSpeechSynthesizer::create(this))
    , m_isPaused(false)
{
    ScriptWrappable::init(this);
}

void SpeechSynthesis::setPlatformSynthesizer(PassOwnPtr<PlatformSpeechSynthesizer> synthesizer)
{
    m_platformSpeechSynthesizer = synthesizer;
}

ExecutionContext* SpeechSynthesis::executionContext() const
{
    return ContextLifecycleObserver::executionContext();
}

void SpeechSynthesis::voicesDidChange()
{
    m_voiceList.clear();
    if (!executionContext()->activeDOMObjectsAreStopped())
        dispatchEvent(Event::create(EventTypeNames::voiceschanged));
}

const WillBeHeapVector<RefPtrWillBeMember<SpeechSynthesisVoice> >& SpeechSynthesis::getVoices()
{
    if (m_voiceList.size())
        return m_voiceList;

    // If the voiceList is empty, that's the cue to get the voices from the platform again.
    const Vector<RefPtr<PlatformSpeechSynthesisVoice> >& platformVoices = m_platformSpeechSynthesizer->voiceList();
    size_t voiceCount = platformVoices.size();
    for (size_t k = 0; k < voiceCount; k++)
        m_voiceList.append(SpeechSynthesisVoice::create(platformVoices[k]));

    return m_voiceList;
}

bool SpeechSynthesis::speaking() const
{
    // If we have a current speech utterance, then that means we're assumed to be in a speaking state.
    // This state is independent of whether the utterance happens to be paused.
    return currentSpeechUtterance();
}

bool SpeechSynthesis::pending() const
{
    // This is true if there are any utterances that have not started.
    // That means there will be more than one in the queue.
    return m_utteranceQueue.size() > 1;
}

bool SpeechSynthesis::paused() const
{
    return m_isPaused;
}

void SpeechSynthesis::startSpeakingImmediately()
{
    SpeechSynthesisUtterance* utterance = currentSpeechUtterance();
    ASSERT(utterance);

    utterance->setStartTime(monotonicallyIncreasingTime());
    m_isPaused = false;
    m_platformSpeechSynthesizer->speak(utterance->platformUtterance());
}

void SpeechSynthesis::speak(SpeechSynthesisUtterance* utterance, ExceptionState& exceptionState)
{
    if (!utterance) {
        exceptionState.throwTypeError("Invalid utterance argument");
        return;
    }

    m_utteranceQueue.append(utterance);

    // If the queue was empty, speak this immediately.
    if (m_utteranceQueue.size() == 1)
        startSpeakingImmediately();
}

void SpeechSynthesis::cancel()
{
    // Remove all the items from the utterance queue. The platform
    // may still have references to some of these utterances and may
    // fire events on them asynchronously.
    m_utteranceQueue.clear();
    m_platformSpeechSynthesizer->cancel();
}

void SpeechSynthesis::pause()
{
    if (!m_isPaused)
        m_platformSpeechSynthesizer->pause();
}

void SpeechSynthesis::resume()
{
    if (!currentSpeechUtterance())
        return;
    m_platformSpeechSynthesizer->resume();
}

void SpeechSynthesis::fireEvent(const AtomicString& type, SpeechSynthesisUtterance* utterance, unsigned long charIndex, const String& name)
{
    if (!executionContext()->activeDOMObjectsAreStopped())
        utterance->dispatchEvent(SpeechSynthesisEvent::create(type, charIndex, (currentTime() - utterance->startTime()), name));
}

void SpeechSynthesis::handleSpeakingCompleted(SpeechSynthesisUtterance* utterance, bool errorOccurred)
{
    ASSERT(utterance);

    bool didJustFinishCurrentUtterance = false;
    // If the utterance that completed was the one we're currently speaking,
    // remove it from the queue and start speaking the next one.
    if (utterance == currentSpeechUtterance()) {
        m_utteranceQueue.removeFirst();
        didJustFinishCurrentUtterance = true;
    }

    // Always fire the event, because the platform may have asynchronously
    // sent an event on an utterance before it got the message that we
    // canceled it, and we should always report to the user what actually
    // happened.
    fireEvent(errorOccurred ? EventTypeNames::error : EventTypeNames::end, utterance, 0, String());

    // Start the next utterance if we just finished one and one was pending.
    if (didJustFinishCurrentUtterance && !m_utteranceQueue.isEmpty())
        startSpeakingImmediately();
}

void SpeechSynthesis::boundaryEventOccurred(PassRefPtr<PlatformSpeechSynthesisUtterance> utterance, SpeechBoundary boundary, unsigned charIndex)
{
    DEFINE_STATIC_LOCAL(const String, wordBoundaryString, ("word"));
    DEFINE_STATIC_LOCAL(const String, sentenceBoundaryString, ("sentence"));

    switch (boundary) {
    case SpeechWordBoundary:
        fireEvent(EventTypeNames::boundary, static_cast<SpeechSynthesisUtterance*>(utterance->client()), charIndex, wordBoundaryString);
        break;
    case SpeechSentenceBoundary:
        fireEvent(EventTypeNames::boundary, static_cast<SpeechSynthesisUtterance*>(utterance->client()), charIndex, sentenceBoundaryString);
        break;
    default:
        ASSERT_NOT_REACHED();
    }
}

void SpeechSynthesis::didStartSpeaking(PassRefPtr<PlatformSpeechSynthesisUtterance> utterance)
{
    if (utterance->client())
        fireEvent(EventTypeNames::start, static_cast<SpeechSynthesisUtterance*>(utterance->client()), 0, String());
}

void SpeechSynthesis::didPauseSpeaking(PassRefPtr<PlatformSpeechSynthesisUtterance> utterance)
{
    m_isPaused = true;
    if (utterance->client())
        fireEvent(EventTypeNames::pause, static_cast<SpeechSynthesisUtterance*>(utterance->client()), 0, String());
}

void SpeechSynthesis::didResumeSpeaking(PassRefPtr<PlatformSpeechSynthesisUtterance> utterance)
{
    m_isPaused = false;
    if (utterance->client())
        fireEvent(EventTypeNames::resume, static_cast<SpeechSynthesisUtterance*>(utterance->client()), 0, String());
}

void SpeechSynthesis::didFinishSpeaking(PassRefPtr<PlatformSpeechSynthesisUtterance> utterance)
{
    if (utterance->client())
        handleSpeakingCompleted(static_cast<SpeechSynthesisUtterance*>(utterance->client()), false);
}

void SpeechSynthesis::speakingErrorOccurred(PassRefPtr<PlatformSpeechSynthesisUtterance> utterance)
{
    if (utterance->client())
        handleSpeakingCompleted(static_cast<SpeechSynthesisUtterance*>(utterance->client()), true);
}

SpeechSynthesisUtterance* SpeechSynthesis::currentSpeechUtterance() const
{
    if (!m_utteranceQueue.isEmpty())
        return m_utteranceQueue.first().get();
    return 0;
}

const AtomicString& SpeechSynthesis::interfaceName() const
{
    return EventTargetNames::SpeechSynthesisUtterance;
}

void SpeechSynthesis::trace(Visitor* visitor)
{
    visitor->trace(m_voiceList);
    visitor->trace(m_utteranceQueue);
}

} // namespace WebCore