/*
 * Copyright (C) 2010, Google 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 INC. AND ITS CONTRIBUTORS ``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 INC. OR ITS 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"

#if ENABLE(WEB_AUDIO)

#include "RealtimeAnalyserNode.h"

#include "AudioNodeInput.h"
#include "AudioNodeOutput.h"

namespace WebCore {

RealtimeAnalyserNode::RealtimeAnalyserNode(AudioContext* context, float sampleRate)
    : AudioNode(context, sampleRate)
{
    addInput(adoptPtr(new AudioNodeInput(this)));
    addOutput(adoptPtr(new AudioNodeOutput(this, 2)));
    
    setNodeType(NodeTypeAnalyser);
    
    initialize();
}

RealtimeAnalyserNode::~RealtimeAnalyserNode()
{
    uninitialize();
}

void RealtimeAnalyserNode::process(size_t framesToProcess)
{
    AudioBus* outputBus = output(0)->bus();

    if (!isInitialized() || !input(0)->isConnected()) {
        outputBus->zero();
        return;
    }

    AudioBus* inputBus = input(0)->bus();
    
    // Give the analyser the audio which is passing through this AudioNode.
    m_analyser.writeInput(inputBus, framesToProcess);

    // For in-place processing, our override of pullInputs() will just pass the audio data through unchanged if the channel count matches from input to output
    // (resulting in inputBus == outputBus).  Otherwise, do an up-mix to stereo.
    if (inputBus != outputBus)
        outputBus->copyFrom(*inputBus);
}

// We override pullInputs() as an optimization allowing this node to take advantage of in-place processing,
// where the input is simply passed through unprocessed to the output.
// Note: this only applies if the input and output channel counts match.
void RealtimeAnalyserNode::pullInputs(size_t framesToProcess)
{
    // Render input stream - try to render directly into output bus for pass-through processing where process() doesn't need to do anything...
    input(0)->pull(output(0)->bus(), framesToProcess);
}

void RealtimeAnalyserNode::reset()
{
    m_analyser.reset();
}

} // namespace WebCore

#endif // ENABLE(WEB_AUDIO)
