/*

    Copyright (C) 1998 Lars Knoll (knoll@mpi-hd.mpg.de)

    Copyright (C) 2001 Dirk Mueller (mueller@kde.org)

    Copyright (C) 2002 Waldo Bastian (bastian@kde.org)

    Copyright (C) 2006 Samuel Weinig (sam.weinig@gmail.com)

    Copyright (C) 2004, 2005, 2006, 2007 Apple Inc. All rights reserved.

    This library is free software; you can redistribute it and/or

    modify it under the terms of the GNU Library General Public

    License as published by the Free Software Foundation; either

    version 2 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,

    but WITHOUT ANY WARRANTY; without even the implied warranty of

    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

    Library General Public License for more details.

    You should have received a copy of the GNU Library General Public License

    along with this library; see the file COPYING.LIB.  If not, write to

    the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,

    Boston, MA 02110-1301, USA.

*/

#include "config.h"

#include "CachedImage.h"

#include "BitmapImage.h"

#include "Cache.h"

#include "CachedResourceClient.h"

#include "CachedResourceClientWalker.h"

#include "DocLoader.h"

#include "Frame.h"

#include "FrameLoaderTypes.h"

#include "FrameView.h"

#include "Request.h"

#include "Settings.h"

#include "SharedBuffer.h"

#include <wtf/CurrentTime.h>

#include <wtf/StdLibExtras.h>

#include <wtf/Vector.h>

#if PLATFORM(CG)

#include "PDFDocumentImage.h"

#endif

#if ENABLE(SVG_AS_IMAGE)

#include "SVGImage.h"

#endif

using std::max;

namespace WebCore {

CachedImage::CachedImage(const String& url)

    : CachedResource(url, ImageResource)

    , m_image(0)

    , m_decodedDataDeletionTimer(this, &CachedImage::decodedDataDeletionTimerFired)

    , m_httpStatusCodeErrorOccurred(false)

{

    setStatus(Unknown);

}

CachedImage::CachedImage(Image* image)

    : CachedResource(String(), ImageResource)

    , m_image(image)

    , m_decodedDataDeletionTimer(this, &CachedImage::decodedDataDeletionTimerFired)

    , m_httpStatusCodeErrorOccurred(false)

{

    setStatus(Cached);

    setLoading(false);

}

CachedImage::~CachedImage()

{

}

void CachedImage::decodedDataDeletionTimerFired(Timer<CachedImage>*)

{

    ASSERT(!hasClients());

    destroyDecodedData();

}

void CachedImage::load(DocLoader* docLoader)

{

    if (!docLoader || docLoader->autoLoadImages())

        CachedResource::load(docLoader, true, DoSecurityCheck, true);

    else

        setLoading(false);

}

void CachedImage::didAddClient(CachedResourceClient* c)

{

    if (m_decodedDataDeletionTimer.isActive())

        m_decodedDataDeletionTimer.stop();

    if (m_data && !m_image && !errorOccurred()) {

        createImage();

        m_image->setData(m_data, true);

    }

    if (m_image && !m_image->isNull())

        c->imageChanged(this);

    if (!isLoading())

        c->notifyFinished(this);

}

void CachedImage::allClientsRemoved()

{

    if (m_image && !errorOccurred())

        m_image->resetAnimation();

    if (double interval = cache()->deadDecodedDataDeletionInterval())

        m_decodedDataDeletionTimer.startOneShot(interval);

}

static Image* brokenImage()

{

    DEFINE_STATIC_LOCAL(RefPtr<Image>, brokenImage, (Image::loadPlatformResource("missingImage")));

    return brokenImage.get();

}

static Image* nullImage()

{

    DEFINE_STATIC_LOCAL(RefPtr<BitmapImage>, nullImage, (BitmapImage::create()));

    return nullImage.get();

}

Image* CachedImage::image() const

{

    ASSERT(!isPurgeable());

    if (errorOccurred())

        return brokenImage();

    if (m_image)

        return m_image.get();

    return nullImage();

}

void CachedImage::setImageContainerSize(const IntSize& containerSize)

{

    if (m_image)

        m_image->setContainerSize(containerSize);

}

bool CachedImage::usesImageContainerSize() const

{

    if (m_image)

        return m_image->usesContainerSize();

    return false;

}

bool CachedImage::imageHasRelativeWidth() const

{

    if (m_image)

        return m_image->hasRelativeWidth();

    return false;

}

bool CachedImage::imageHasRelativeHeight() const

{

    if (m_image)

        return m_image->hasRelativeHeight();

    return false;

}

IntSize CachedImage::imageSize(float multiplier) const

{

    ASSERT(!isPurgeable());

    if (!m_image)

        return IntSize();

    if (multiplier == 1.0f)

        return m_image->size();

    // Don't let images that have a width/height >= 1 shrink below 1 when zoomed.

    bool hasWidth = m_image->size().width() > 0;

    bool hasHeight = m_image->size().height() > 0;

    int width = m_image->size().width() * (m_image->hasRelativeWidth() ? 1.0f : multiplier);

    int height = m_image->size().height() * (m_image->hasRelativeHeight() ? 1.0f : multiplier);

    if (hasWidth)

        width = max(1, width);

    if (hasHeight)

        height = max(1, height);

    return IntSize(width, height);

}

IntRect CachedImage::imageRect(float multiplier) const

{

    ASSERT(!isPurgeable());

    if (!m_image)

        return IntRect();

    if (multiplier == 1.0f || (!m_image->hasRelativeWidth() && !m_image->hasRelativeHeight()))

        return m_image->rect();

    float widthMultiplier = (m_image->hasRelativeWidth() ? 1.0f : multiplier);

    float heightMultiplier = (m_image->hasRelativeHeight() ? 1.0f : multiplier);

    // Don't let images that have a width/height >= 1 shrink below 1 when zoomed.

    bool hasWidth = m_image->rect().width() > 0;

    bool hasHeight = m_image->rect().height() > 0;

    int width = static_cast<int>(m_image->rect().width() * widthMultiplier);

    int height = static_cast<int>(m_image->rect().height() * heightMultiplier);

    if (hasWidth)

        width = max(1, width);

    if (hasHeight)

        height = max(1, height);

    int x = static_cast<int>(m_image->rect().x() * widthMultiplier);

    int y = static_cast<int>(m_image->rect().y() * heightMultiplier);

    return IntRect(x, y, width, height);

}

void CachedImage::notifyObservers(const IntRect* changeRect)

{

    CachedResourceClientWalker w(m_clients);

    while (CachedResourceClient* c = w.next())

        c->imageChanged(this, changeRect);

}

void CachedImage::clear()

{

    destroyDecodedData();

    m_image = 0;

    setEncodedSize(0);

}

inline void CachedImage::createImage()

{

    // Create the image if it doesn't yet exist.

    if (m_image)

        return;

#if PLATFORM(CG)

    if (m_response.mimeType() == "application/pdf") {

        m_image = PDFDocumentImage::create();

        return;

    }

#endif

#if ENABLE(SVG_AS_IMAGE)

    if (m_response.mimeType() == "image/svg+xml") {

        m_image = SVGImage::create(this);

        return;

    }

#endif

    m_image = BitmapImage::create(this);

}

size_t CachedImage::maximumDecodedImageSize()

{

    Frame* frame = m_request ? m_request->docLoader()->frame() : 0;

    if (!frame)

        return 0;

    Settings* settings = frame->settings();

    return settings ? settings->maximumDecodedImageSize() : 0;

}

void CachedImage::data(PassRefPtr<SharedBuffer> data, bool allDataReceived)

{

    m_data = data;

    createImage();

    bool sizeAvailable = false;

    // Have the image update its data from its internal buffer.

    // It will not do anything now, but will delay decoding until 

    // queried for info (like size or specific image frames).

    sizeAvailable = m_image->setData(m_data, allDataReceived);

    // Go ahead and tell our observers to try to draw if we have either

    // received all the data or the size is known.  Each chunk from the

    // network causes observers to repaint, which will force that chunk

    // to decode.

    if (sizeAvailable || allDataReceived) {

        size_t maxDecodedImageSize = maximumDecodedImageSize();

        IntSize s = imageSize(1.0f);

        size_t estimatedDecodedImageSize = s.width() * s.height() * 4; // no overflow check

        if (m_image->isNull() || (maxDecodedImageSize > 0 && estimatedDecodedImageSize > maxDecodedImageSize)) {

            error();

            if (inCache())

                cache()->remove(this);

            return;

        }

        // It would be nice to only redraw the decoded band of the image, but with the current design

        // (decoding delayed until painting) that seems hard.

        notifyObservers();

        if (m_image)

            setEncodedSize(m_image->data() ? m_image->data()->size() : 0);

    }

    if (allDataReceived) {

        setLoading(false);

        checkNotify();

    }

}

void CachedImage::error()

{

    clear();

    setErrorOccurred(true);

    m_data.clear();

    notifyObservers();

    setLoading(false);

    checkNotify();

}

void CachedImage::checkNotify()

{

    if (isLoading())

        return;

    CachedResourceClientWalker w(m_clients);

    while (CachedResourceClient* c = w.next())

        c->notifyFinished(this);

}

void CachedImage::destroyDecodedData()

{

    bool canDeleteImage = !m_image || (m_image->hasOneRef() && m_image->isBitmapImage());

    if (isSafeToMakePurgeable() && canDeleteImage && !isLoading()) {

        // Image refs the data buffer so we should not make it purgeable while the image is alive. 

        // Invoking addClient() will reconstruct the image object.

        m_image = 0;

        setDecodedSize(0);

        makePurgeable(true);

    } else if (m_image && !errorOccurred())

        m_image->destroyDecodedData();

}

void CachedImage::decodedSizeChanged(const Image* image, int delta)

{

    if (image != m_image)

        return;

    setDecodedSize(decodedSize() + delta);

}

void CachedImage::didDraw(const Image* image)

{

    if (image != m_image)

        return;

    double timeStamp = FrameView::currentPaintTimeStamp();

    if (!timeStamp) // If didDraw is called outside of a Frame paint.

        timeStamp = currentTime();

    CachedResource::didAccessDecodedData(timeStamp);

}

bool CachedImage::shouldPauseAnimation(const Image* image)

{

    if (image != m_image)

        return false;

    CachedResourceClientWalker w(m_clients);

    while (CachedResourceClient* c = w.next()) {

        if (c->willRenderImage(this))

            return false;

    }

    return true;

}

void CachedImage::animationAdvanced(const Image* image)

{

    if (image == m_image)

        notifyObservers();

}

void CachedImage::changedInRect(const Image* image, const IntRect& rect)

{

    if (image == m_image)

        notifyObservers(&rect);

}

} //namespace WebCore