/**

 * This file is part of the DOM implementation for KDE.

 *

 * Copyright (C) 1999 Lars Knoll (knoll@kde.org)

 *           (C) 1999 Antti Koivisto (koivisto@kde.org)

 *           (C) 2000 Dirk Mueller (mueller@kde.org)

 *           (C) 2006 Allan Sandfeld Jensen (kde@carewolf.com)

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

 * Copyright (C) 2003, 2004, 2005, 2006 Apple Computer, Inc.

 *

 * 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 "RenderImage.h"

#include "BitmapImage.h"

#include "Document.h"

#include "GraphicsContext.h"

#include "HTMLImageElement.h"

#include "HTMLInputElement.h"

#include "HTMLMapElement.h"

#include "HTMLNames.h"

#include "HitTestResult.h"

#include "Page.h"

#include "RenderView.h"

#include "TextStyle.h"

using namespace std;

namespace WebCore {

using namespace HTMLNames;

RenderImage::RenderImage(Node* node)

    : RenderReplaced(node, IntSize(0, 0))

    , m_cachedImage(0)

    , m_isAnonymousImage(false)

{

    updateAltText();

}

RenderImage::~RenderImage()

{

    if (m_cachedImage)

        m_cachedImage->deref(this);

}

void RenderImage::setCachedImage(CachedImage* newImage)

{

    if (m_isAnonymousImage || m_cachedImage == newImage)

        return;

    if (m_cachedImage)

        m_cachedImage->deref(this);

    m_cachedImage = newImage;

    if (m_cachedImage) {

        m_cachedImage->ref(this);

        if (m_cachedImage->errorOccurred())

            imageChanged(m_cachedImage);

    }

}

// If we'll be displaying either alt text or an image, add some padding.

static const unsigned short paddingWidth = 4;

static const unsigned short paddingHeight = 4;

// Alt text is restricted to this maximum size, in pixels.  These are

// signed integers because they are compared with other signed values.

static const int maxAltTextWidth = 1024;

static const int maxAltTextHeight = 256;

// Sets the image height and width to fit the alt text.  Returns true if the

// image size changed.

bool RenderImage::setImageSizeForAltText(CachedImage* newImage /* = 0 */)

{

    int imageWidth = 0;

    int imageHeight = 0;

    // If we'll be displaying either text or an image, add a little padding.

    if (!m_altText.isEmpty() || newImage) {

        imageWidth = paddingWidth;

        imageHeight = paddingHeight;

    }

    if (newImage) {

        imageWidth += newImage->image()->width();

        imageHeight += newImage->image()->height();

    }

    // we have an alt and the user meant it (its not a text we invented)

    if (!m_altText.isEmpty()) {

        const Font& font = style()->font();

        imageWidth = max(imageWidth, min(font.width(TextRun(m_altText.characters(), m_altText.length())), maxAltTextWidth));

#if PLATFORM(SYMBIAN)

        // display both alt text and broken image

        imageHeight+= min(font.height(), maxAltTextHeight);

#else

        imageHeight = max(imageHeight, min(font.height(), maxAltTextHeight));

#endif

    }

    IntSize imageSize = IntSize(imageWidth, imageHeight);

    if (imageSize == intrinsicSize())

        return false;

    setIntrinsicSize(imageSize);

    return true;

}

void RenderImage::imageChanged(CachedImage* newImage)

{

    if (documentBeingDestroyed())

        return;

    if (hasBoxDecorations())

        RenderReplaced::imageChanged(newImage);

    if (newImage != m_cachedImage)

        return;

    bool imageSizeChanged = false;

    // Set image dimensions, taking into account the size of the alt text.

    if (newImage->errorOccurred())

        imageSizeChanged = setImageSizeForAltText(newImage);

    bool shouldRepaint = true;

    // Image dimensions have been changed, see what needs to be done

    if (newImage->imageSize() != intrinsicSize() || imageSizeChanged) {

        if (!newImage->errorOccurred())

            setIntrinsicSize(newImage->imageSize());

        // In the case of generated image content using :before/:after, we might not be in the

        // render tree yet.  In that case, we don't need to worry about check for layout, since we'll get a

        // layout when we get added in to the render tree hierarchy later.

        if (containingBlock()) {

            // lets see if we need to relayout at all..

            int oldwidth = m_width;

            int oldheight = m_height;

            if (!prefWidthsDirty())

                setPrefWidthsDirty(true);

            calcWidth();

            calcHeight();

            if (imageSizeChanged || m_width != oldwidth || m_height != oldheight) {

                shouldRepaint = false;

                if (!selfNeedsLayout())

                    setNeedsLayout(true);

            }

            m_width = oldwidth;

            m_height = oldheight;

        }

    }

    if (shouldRepaint)

        // FIXME: We always just do a complete repaint, since we always pass in the full image

        // rect at the moment anyway.

        repaintRectangle(contentBox());

}

void RenderImage::resetAnimation()

{

    if (m_cachedImage) {

        image()->resetAnimation();

        if (!needsLayout())

            repaint();

    }

}

void RenderImage::paint(PaintInfo& paintInfo, int tx, int ty)

{

    if (!shouldPaint(paintInfo, tx, ty))

        return;

    tx += m_x;

    ty += m_y;

    if (hasBoxDecorations() && paintInfo.phase != PaintPhaseOutline && paintInfo.phase != PaintPhaseSelfOutline) 

        paintBoxDecorations(paintInfo, tx, ty);

    GraphicsContext* context = paintInfo.context;

    if ((paintInfo.phase == PaintPhaseOutline || paintInfo.phase == PaintPhaseSelfOutline) && style()->outlineWidth() && style()->visibility() == VISIBLE)

        paintOutline(context, tx, ty, width(), height(), style());

    if (paintInfo.phase != PaintPhaseForeground && paintInfo.phase != PaintPhaseSelection)

        return;

    if (!shouldPaintWithinRoot(paintInfo))

        return;

    bool isPrinting = document()->printing();

    bool drawSelectionTint = isSelected() && !isPrinting;

    if (paintInfo.phase == PaintPhaseSelection) {

        if (selectionState() == SelectionNone)

            return;

        drawSelectionTint = false;

    }

    int cWidth = contentWidth();

    int cHeight = contentHeight();

    int leftBorder = borderLeft();

    int topBorder = borderTop();

    int leftPad = paddingLeft();

    int topPad = paddingTop();

    if (isPrinting && !view()->printImages())

        return;

    if (!m_cachedImage || errorOccurred()) {

        if (paintInfo.phase == PaintPhaseSelection)

            return;

        if (cWidth > 2 && cHeight > 2) {

            if (!errorOccurred()) {

                context->setStrokeStyle(SolidStroke);

                context->setStrokeColor(Color::lightGray);

                context->setFillColor(Color::transparent);

                context->drawRect(IntRect(tx + leftBorder + leftPad, ty + topBorder + topPad, cWidth, cHeight));

            }

            bool errorPictureDrawn = false;

            int imageX = 0;

            int imageY = 0;

            int usableWidth = cWidth;

            int usableHeight = cHeight;

            if (errorOccurred() && !image()->isNull() && (usableWidth >= image()->width()) && (usableHeight >= image()->height())) {

                // Center the error image, accounting for border and padding.

                int centerX = (usableWidth - image()->width()) / 2;

                if (centerX < 0)

                    centerX = 0;

#if PLATFORM(SYMBIAN)

                // push image to the bottom to make space for alt text. centerY is a little bit misleading here

                int centerY = usableHeight - image()->height();

#else

                int centerY = (usableHeight - image()->height()) / 2;                

#endif                

                if (centerY < 0)

                    centerY = 0;

                imageX = leftBorder + leftPad + centerX;

                imageY = topBorder + topPad + centerY;

                context->drawImage(image(), IntPoint(tx + imageX, ty + imageY));

                errorPictureDrawn = true;

            }

            if (!m_altText.isEmpty()) {

                DeprecatedString text = m_altText.deprecatedString();

                text.replace('\\', backslashAsCurrencySymbol());

                context->setFont(style()->font());

                context->setFillColor(style()->color());

                int ax = tx + leftBorder + leftPad;

                int ay = ty + topBorder + topPad;

                const Font& font = style()->font();

                int ascent = font.ascent();

                // Only draw the alt text if it'll fit within the content box,

                // and only if it fits above the error image.

                TextRun textRun(reinterpret_cast<const UChar*>(text.unicode()), text.length());

                int textWidth = font.width(textRun);

                if (errorPictureDrawn) {

                    if (usableWidth >= textWidth && font.height() <= imageY)

                        context->drawText(textRun, IntPoint(ax, ay + ascent));

                } else if (usableWidth >= textWidth && cHeight >= font.height())

                    context->drawText(textRun, IntPoint(ax, ay + ascent));

            }

        }

    } else if (m_cachedImage && !image()->isNull()) {

#if PLATFORM(MAC)

        if (style()->highlight() != nullAtom && !paintInfo.context->paintingDisabled())

            paintCustomHighlight(tx - m_x, ty - m_y, style()->highlight(), true);

#endif

        IntRect rect(IntPoint(tx + leftBorder + leftPad, ty + topBorder + topPad), IntSize(cWidth, cHeight));

        HTMLImageElement* imageElt = (element() && element()->hasTagName(imgTag)) ? static_cast<HTMLImageElement*>(element()) : 0;

        CompositeOperator compositeOperator = imageElt ? imageElt->compositeOperator() : CompositeSourceOver;

        context->drawImage(image(), rect, compositeOperator, document()->page()->inLowQualityImageInterpolationMode());

    }

    // draw the selection tint even if the image itself is not available

    if (drawSelectionTint)

        context->fillRect(selectionRect(), selectionBackgroundColor());

}

void RenderImage::layout()

{

    ASSERT(needsLayout());

    IntRect oldBounds;

    IntRect oldOutlineBox;

    bool checkForRepaint = checkForRepaintDuringLayout();

    if (checkForRepaint) {

        oldBounds = absoluteClippedOverflowRect();

        oldOutlineBox = absoluteOutlineBox();

    }

    // minimum height

    m_height = m_cachedImage && m_cachedImage->errorOccurred() ? intrinsicSize().height() : 0;

    calcWidth();

    calcHeight();

    adjustOverflowForBoxShadow();

    if (checkForRepaint)

        repaintAfterLayoutIfNeeded(oldBounds, oldOutlineBox);

    setNeedsLayout(false);

}

HTMLMapElement* RenderImage::imageMap()

{

    HTMLImageElement* i = element() && element()->hasTagName(imgTag) ? static_cast<HTMLImageElement*>(element()) : 0;

    return i ? i->document()->getImageMap(i->imageMap()) : 0;

}

bool RenderImage::nodeAtPoint(const HitTestRequest& request, HitTestResult& result, int _x, int _y, int _tx, int _ty, HitTestAction hitTestAction)

{

    bool inside = RenderReplaced::nodeAtPoint(request, result, _x, _y, _tx, _ty, hitTestAction);

    if (inside && element()) {

        int tx = _tx + m_x;

        int ty = _ty + m_y;

        HTMLMapElement* map = imageMap();

        if (map) {

            // we're a client side image map

            inside = map->mapMouseEvent(_x - tx, _y - ty, IntSize(contentWidth(), contentHeight()), result);

            result.setInnerNonSharedNode(element());

        }

    }

    return inside;

}

void RenderImage::updateAltText()

{

    if (!element())

        return;

    if (element()->hasTagName(inputTag))

        m_altText = static_cast<HTMLInputElement*>(element())->altText();

    else if (element()->hasTagName(imgTag))

        m_altText = static_cast<HTMLImageElement*>(element())->altText();

}

bool RenderImage::isWidthSpecified() const

{

    switch (style()->width().type()) {

        case Fixed:

        case Percent:

            return true;

        default:

            return false;

    }

}

bool RenderImage::isHeightSpecified() const

{

    switch (style()->height().type()) {

        case Fixed:

        case Percent:

            return true;

        default:

            return false;

    }

}

int RenderImage::calcReplacedWidth() const

{

    int width;

    if (isWidthSpecified())

        width = calcReplacedWidthUsing(style()->width());

    else

        width = calcAspectRatioWidth();

    int minW = calcReplacedWidthUsing(style()->minWidth());

    int maxW = style()->maxWidth().isUndefined() ? width : calcReplacedWidthUsing(style()->maxWidth());

    return max(minW, min(width, maxW));

}

int RenderImage::calcReplacedHeight() const

{

    int height;

    if (isHeightSpecified())

        height = calcReplacedHeightUsing(style()->height());

    else

        height = calcAspectRatioHeight();

    int minH = calcReplacedHeightUsing(style()->minHeight());

    int maxH = style()->maxHeight().isUndefined() ? height : calcReplacedHeightUsing(style()->maxHeight());

    return max(minH, min(height, maxH));

}

int RenderImage::calcAspectRatioWidth() const

{

    IntSize size = intrinsicSize();

    if (!size.height())

        return 0;

    if (!m_cachedImage || m_cachedImage->errorOccurred())

        return size.width(); // Don't bother scaling.

    return RenderReplaced::calcReplacedHeight() * size.width() / size.height();

}

int RenderImage::calcAspectRatioHeight() const

{

    IntSize size = intrinsicSize();

    if (!size.width())

        return 0;

    if (!m_cachedImage || m_cachedImage->errorOccurred())

        return size.height(); // Don't bother scaling.

    return RenderReplaced::calcReplacedWidth() * size.height() / size.width();

}

void RenderImage::calcPrefWidths()

{

    ASSERT(prefWidthsDirty());

    m_maxPrefWidth = calcReplacedWidth() + paddingLeft() + paddingRight() + borderLeft() + borderRight();

    if (style()->width().isPercent() || style()->height().isPercent() || 

        style()->maxWidth().isPercent() || style()->maxHeight().isPercent() ||

        style()->minWidth().isPercent() || style()->minHeight().isPercent())

        m_minPrefWidth = 0;

    else

        m_minPrefWidth = m_maxPrefWidth;

    setPrefWidthsDirty(false);

}

Image* RenderImage::nullImage()

{

    static BitmapImage sharedNullImage;

    return &sharedNullImage;

}

} // namespace WebCore