/*

 * Copyright (C) 2006 Friedemann Kleint <fkleint@trolltech.com>

 * Copyright (C) 2008 Nokia Corporation and/or its subsidiary(-ies)

 *

 * 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 "ImageDecoderQt.h"

#include <QtCore/QByteArray>

#include <QtCore/QBuffer>

#include <QtGui/QImageReader>

#include <qdebug.h>

namespace WebCore {

ImageDecoder* ImageDecoder::create(const SharedBuffer& data)

{

    // We need at least 4 bytes to figure out what kind of image we're dealing with.

    if (data.size() < 4)

        return 0;

    return new ImageDecoderQt;

}

ImageDecoderQt::ImageDecoderQt()

    : m_repetitionCount(cAnimationNone)

{

}

ImageDecoderQt::~ImageDecoderQt()

{

}

void ImageDecoderQt::setData(SharedBuffer* data, bool allDataReceived)

{

    if (failed())

        return;

    // No progressive loading possible

    if (!allDataReceived)

        return;

    // Cache our own new data.

    ImageDecoder::setData(data, allDataReceived);

    // We expect to be only called once with allDataReceived

    ASSERT(!m_buffer);

    ASSERT(!m_reader);

    // Attempt to load the data

    QByteArray imageData = QByteArray::fromRawData(m_data->data(), m_data->size());

    m_buffer.set(new QBuffer);

    m_buffer->setData(imageData);

    m_buffer->open(QIODevice::ReadOnly | QIODevice::Unbuffered);

    m_reader.set(new QImageReader(m_buffer.get(), m_format));

    // QImageReader only allows retrieving the format before reading the image

    m_format = m_reader->format();

}

bool ImageDecoderQt::isSizeAvailable()

{

    if (!ImageDecoder::isSizeAvailable() && m_reader)

        internalDecodeSize();

    return ImageDecoder::isSizeAvailable();

}

size_t ImageDecoderQt::frameCount()

{

    if (m_frameBufferCache.isEmpty() && m_reader) {

        if (m_reader->supportsAnimation()) {

            int imageCount = m_reader->imageCount();

            // Fixup for Qt decoders... imageCount() is wrong

            // and jumpToNextImage does not work either... so

            // we will have to parse everything...

            if (!imageCount)

                forceLoadEverything();

            else

                m_frameBufferCache.resize(imageCount);

        } else

            m_frameBufferCache.resize(1);

    }

    return m_frameBufferCache.size();

}

int ImageDecoderQt::repetitionCount() const

{

    if (m_reader && m_reader->supportsAnimation())

        m_repetitionCount = m_reader->loopCount();

    return m_repetitionCount;

}

String ImageDecoderQt::filenameExtension() const

{

    return String(m_format.constData(), m_format.length());

};

RGBA32Buffer* ImageDecoderQt::frameBufferAtIndex(size_t index)

{

    // In case the ImageDecoderQt got recreated we don't know

    // yet how many images we are going to have and need to

    // find that out now.

    size_t count = m_frameBufferCache.size();

    if (!failed() && !count) {

        internalDecodeSize();

        count = frameCount();

    }

    if (index >= count)

        return 0;

    RGBA32Buffer& frame = m_frameBufferCache[index];

    if (frame.status() != RGBA32Buffer::FrameComplete && m_reader)

        internalReadImage(index);

    return &frame;

}

void ImageDecoderQt::clearFrameBufferCache(size_t /*index*/)

{

}

void ImageDecoderQt::internalDecodeSize()

{

    ASSERT(m_reader);

    // If we have a QSize() something failed

    QSize size = m_reader->size();

    if (size.isEmpty()) {

        setFailed();

        return clearPointers();

    }

    setSize(size.width(), size.height());

}

void ImageDecoderQt::internalReadImage(size_t frameIndex)

{

    ASSERT(m_reader);

    if (m_reader->supportsAnimation())

        m_reader->jumpToImage(frameIndex);

    else if (frameIndex) {

        setFailed();

        return clearPointers();

    }

    if (!internalHandleCurrentImage(frameIndex))

      setFailed();

    // Attempt to return some memory

    for (int i = 0; i < m_frameBufferCache.size(); ++i) {

        if (m_frameBufferCache[i].status() != RGBA32Buffer::FrameComplete)

            return;

    }

    clearPointers();

}

bool ImageDecoderQt::internalHandleCurrentImage(size_t frameIndex)

{

    QPixmap pixmap;

        frameCount();

        repetitionCount();

        clearPointers();

        return false;

    }

    // now into the RGBA32Buffer - even if the image is not

    RGBA32Buffer* const buffer = &m_frameBufferCache[frameIndex];

    buffer->setRect(m_reader->currentImageRect());

    buffer->setStatus(RGBA32Buffer::FrameComplete);

    buffer->setDuration(m_reader->nextImageDelay());

    buffer->setPixmap(pixmap);

    return true;

}

// The QImageIOHandler is not able to tell us how many frames

// we have and we need to parse every image. We do this by

// increasing the m_frameBufferCache by one and try to parse

// the image. We stop when QImage::read fails and then need

// to resize the m_frameBufferCache to the final size and update

// the failed bit. If we failed to decode the first image

// then we truly failed to decode, otherwise we're OK.

// TODO: Do not increment the m_frameBufferCache.size() by one but more than one

void ImageDecoderQt::forceLoadEverything()

{

    int imageCount = 0;

    do {

        m_frameBufferCache.resize(++imageCount);

    } while (internalHandleCurrentImage(imageCount - 1));

    // If we failed decoding the first image we actually

    // have no images and need to set the failed bit.

    // Otherwise, we want to forget about

    // the last attempt to decode a image.

    m_frameBufferCache.resize(imageCount - 1);

    if (imageCount == 1)

      setFailed();

}

void ImageDecoderQt::clearPointers()

{

    m_reader.clear();

    m_buffer.clear();

}

}

// vim: ts=4 sw=4 et