htmlimageelement.cpp

linux下开源浏览器WebKit的源码,市面上的很多商用浏览器都是移植自WebKit

/*
 * Copyright (C) 1999 Lars Knoll ([e-mail])
 *           (C) 1999 Antti Koivisto ([e-mail])
 * Copyright (C) 2004, 2005, 2006, 2007, 2008 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 "HTMLImageElement.h"

#include "CSSHelper.h"
#include "CSSPropertyNames.h"
#include "CSSValueKeywords.h"
#include "EventNames.h"
#include "Frame.h"
#include "HTMLDocument.h"
#include "HTMLFormElement.h"
#include "HTMLNames.h"
#include "RenderImage.h"

using namespace std;

namespace WebCore {

using namespace HTMLNames;

HTMLImageElement::HTMLImageElement(const QualifiedName& tagName, Document* doc, HTMLFormElement* form)
    : HTMLElement(tagName, doc)
    , m_imageLoader(this)
    , ismap(false)
    , m_form(form)
    , m_compositeOperator(CompositeSourceOver)
{
    ASSERT(hasTagName(imgTag));
    if (form)
        form->registerImgElement(this);
}

HTMLImageElement::~HTMLImageElement()
{
    if (m_form)
        m_form->removeImgElement(this);
}

bool HTMLImageElement::mapToEntry(const QualifiedName& attrName, MappedAttributeEntry& result) const
{
    if (attrName == widthAttr ||
        attrName == heightAttr ||
        attrName == vspaceAttr ||
        attrName == hspaceAttr ||
        attrName == valignAttr) {
        result = eUniversal;
        return false;
    }
    
    if (attrName == borderAttr || attrName == alignAttr) {
        result = eReplaced; // Shared with embed and iframe elements.
        return false;
    }

    return HTMLElement::mapToEntry(attrName, result);
}

void HTMLImageElement::parseMappedAttribute(MappedAttribute* attr)
{
    const QualifiedName& attrName = attr->name();
    if (attrName == altAttr) {
        if (renderer() && renderer()->isImage())
            toRenderImage(renderer())->updateAltText();
    } else if (attrName == srcAttr)
        m_imageLoader.updateFromElementIgnoringPreviousError();
    else if (attrName == widthAttr)
        addCSSLength(attr, CSSPropertyWidth, attr->value());
    else if (attrName == heightAttr)
        addCSSLength(attr, CSSPropertyHeight, attr->value());
    else if (attrName == borderAttr) {
        // border="noborder" -> border="0"
        addCSSLength(attr, CSSPropertyBorderWidth, attr->value().toInt() ? attr->value() : "0");
        addCSSProperty(attr, CSSPropertyBorderTopStyle, CSSValueSolid);
        addCSSProperty(attr, CSSPropertyBorderRightStyle, CSSValueSolid);
        addCSSProperty(attr, CSSPropertyBorderBottomStyle, CSSValueSolid);
        addCSSProperty(attr, CSSPropertyBorderLeftStyle, CSSValueSolid);
    } else if (attrName == vspaceAttr) {
        addCSSLength(attr, CSSPropertyMarginTop, attr->value());
        addCSSLength(attr, CSSPropertyMarginBottom, attr->value());
    } else if (attrName == hspaceAttr) {
        addCSSLength(attr, CSSPropertyMarginLeft, attr->value());
        addCSSLength(attr, CSSPropertyMarginRight, attr->value());
    } else if (attrName == alignAttr)
        addHTMLAlignment(attr);
    else if (attrName == valignAttr)
        addCSSProperty(attr, CSSPropertyVerticalAlign, attr->value());
    else if (attrName == usemapAttr) {
        if (attr->value().string()[0] == '#')
            usemap = attr->value();
        else
            usemap = document()->completeURL(parseURL(attr->value())).string();
        setIsLink(!attr->isNull());
    } else if (attrName == ismapAttr)
        ismap = true;
    else if (attrName == onabortAttr)
        setInlineEventListenerForTypeAndAttribute(eventNames().abortEvent, attr);
    else if (attrName == onloadAttr)
        setInlineEventListenerForTypeAndAttribute(eventNames().loadEvent, attr);
    else if (attrName == compositeAttr) {
        if (!parseCompositeOperator(attr->value(), m_compositeOperator))
            m_compositeOperator = CompositeSourceOver;
    } else if (attrName == nameAttr) {
        const AtomicString& newName = attr->value();
        if (inDocument() && document()->isHTMLDocument()) {
            HTMLDocument* document = static_cast<HTMLDocument*>(this->document());
            document->removeNamedItem(m_name);
            document->addNamedItem(newName);
        }
        m_name = newName;
    } else if (attr->name() == idAttr) {
        const AtomicString& newId = attr->value();
        if (inDocument() && document()->isHTMLDocument()) {
            HTMLDocument* document = static_cast<HTMLDocument*>(this->document());
            document->removeExtraNamedItem(m_id);
            document->addExtraNamedItem(newId);
        }
        m_id = newId;
        // also call superclass
        HTMLElement::parseMappedAttribute(attr);
    } else
        HTMLElement::parseMappedAttribute(attr);
}

String HTMLImageElement::altText() const
{
    // lets figure out the alt text.. magic stuff
    // http://www.w3.org/TR/1998/REC-html40-19980424/appendix/notes.html#altgen
    // also heavily discussed by Hixie on bugzilla
    String alt = getAttribute(altAttr);
    // fall back to title attribute
    if (alt.isNull())
        alt = getAttribute(titleAttr);
    return alt;
}

RenderObject* HTMLImageElement::createRenderer(RenderArena* arena, RenderStyle* style)
{
     if (style->contentData())
        return RenderObject::createObject(this, style);
     
     return new (arena) RenderImage(this);
}

void HTMLImageElement::attach()
{
    HTMLElement::attach();

    if (renderer() && renderer()->isImage()) {
        RenderImage* imageObj = toRenderImage(renderer());
        if (imageObj->hasImage())
            return;
        imageObj->setCachedImage(m_imageLoader.image());
        
        // If we have no image at all because we have no src attribute, set
        // image height and width for the alt text instead.
        if (!m_imageLoader.image() && !imageObj->cachedImage())
            imageObj->setImageSizeForAltText();
    }
}

void HTMLImageElement::insertedIntoDocument()
{
    if (document()->isHTMLDocument()) {
        HTMLDocument* document = static_cast<HTMLDocument*>(this->document());
        document->addNamedItem(m_name);
        document->addExtraNamedItem(m_id);
    }

    // If we have been inserted from a renderer-less document,
    // our loader may have not fetched the image, so do it now.
    if (!m_imageLoader.image())
        m_imageLoader.updateFromElement();

    HTMLElement::insertedIntoDocument();
}

void HTMLImageElement::removedFromDocument()
{
    if (document()->isHTMLDocument()) {
        HTMLDocument* document = static_cast<HTMLDocument*>(this->document());
        document->removeNamedItem(m_name);
        document->removeExtraNamedItem(m_id);
    }

    HTMLElement::removedFromDocument();
}

int HTMLImageElement::width(bool ignorePendingStylesheets) const
{
    if (!renderer()) {
        // check the attribute first for an explicit pixel value
        bool ok;
        int width = getAttribute(widthAttr).toInt(&ok);
        if (ok)
            return width;
        
        // if the image is available, use its width
        if (m_imageLoader.image()) {
            float zoomFactor = document()->frame() ? document()->frame()->pageZoomFactor() : 1.0f;
            return m_imageLoader.image()->imageSize(zoomFactor).width();
        }
    }

    if (ignorePendingStylesheets)
        document()->updateLayoutIgnorePendingStylesheets();
    else
        document()->updateLayout();

    return renderBox() ? renderBox()->contentWidth() : 0;
}

int HTMLImageElement::height(bool ignorePendingStylesheets) const
{
    if (!renderer()) {
        // check the attribute first for an explicit pixel value
        bool ok;
        int height = getAttribute(heightAttr).toInt(&ok);
        if (ok)
            return height;
        
        // if the image is available, use its height
        if (m_imageLoader.image()) {
            float zoomFactor = document()->frame() ? document()->frame()->pageZoomFactor() : 1.0f;
            return m_imageLoader.image()->imageSize(zoomFactor).height();
        }
    }

    if (ignorePendingStylesheets)
        document()->updateLayoutIgnorePendingStylesheets();
    else
        document()->updateLayout();

    return renderBox() ? renderBox()->contentHeight() : 0;
}

int HTMLImageElement::naturalWidth() const
{
    if (!m_imageLoader.image())
        return 0;

    return m_imageLoader.image()->imageSize(1.0f).width();
}

int HTMLImageElement::naturalHeight() const
{
    if (!m_imageLoader.image())
        return 0;
    
    return m_imageLoader.image()->imageSize(1.0f).height();
}
    
bool HTMLImageElement::isURLAttribute(Attribute* attr) const
{
    return attr->name() == srcAttr
        || attr->name() == lowsrcAttr
        || attr->name() == longdescAttr
        || (attr->name() == usemapAttr && attr->value().string()[0] != '#');
}

String HTMLImageElement::name() const
{
    return getAttribute(nameAttr);
}

void HTMLImageElement::setName(const String& value)
{
    setAttribute(nameAttr, value);
}

String HTMLImageElement::align() const
{
    return getAttribute(alignAttr);
}

void HTMLImageElement::setAlign(const String& value)
{
    setAttribute(alignAttr, value);
}

String HTMLImageElement::alt() const
{
    return getAttribute(altAttr);
}

void HTMLImageElement::setAlt(const String& value)
{
    setAttribute(altAttr, value);
}

String HTMLImageElement::border() const
{
    return getAttribute(borderAttr);
}

void HTMLImageElement::setBorder(const String& value)
{
    setAttribute(borderAttr, value);
}

void HTMLImageElement::setHeight(int value)
{
    setAttribute(heightAttr, String::number(value));
}

int HTMLImageElement::hspace() const
{
    // ### return actual value
    return getAttribute(hspaceAttr).toInt();
}

void HTMLImageElement::setHspace(int value)
{
    setAttribute(hspaceAttr, String::number(value));
}

bool HTMLImageElement::isMap() const
{
    return !getAttribute(ismapAttr).isNull();
}

void HTMLImageElement::setIsMap(bool isMap)
{
    setAttribute(ismapAttr, isMap ? "" : 0);
}

KURL HTMLImageElement::longDesc() const
{
    return document()->completeURL(getAttribute(longdescAttr));
}

void HTMLImageElement::setLongDesc(const String& value)
{
    setAttribute(longdescAttr, value);
}

KURL HTMLImageElement::lowsrc() const
{
    return document()->completeURL(getAttribute(lowsrcAttr));
}

void HTMLImageElement::setLowsrc(const String& value)
{
    setAttribute(lowsrcAttr, value);
}

KURL HTMLImageElement::src() const
{
    return document()->completeURL(getAttribute(srcAttr));
}

void HTMLImageElement::setSrc(const String& value)
{
    setAttribute(srcAttr, value);
}

String HTMLImageElement::useMap() const
{
    return getAttribute(usemapAttr);
}

void HTMLImageElement::setUseMap(const String& value)
{
    setAttribute(usemapAttr, value);
}

int HTMLImageElement::vspace() const
{
    // ### return actual vspace
    return getAttribute(vspaceAttr).toInt();
}

void HTMLImageElement::setVspace(int value)
{
    setAttribute(vspaceAttr, String::number(value));
}

void HTMLImageElement::setWidth(int value)
{
    setAttribute(widthAttr, String::number(value));
}

int HTMLImageElement::x() const
{
    RenderObject* r = renderer();
    if (!r)
        return 0;

    // FIXME: This doesn't work correctly with transforms.
    FloatPoint absPos = r->localToAbsolute();
    return absPos.x();
}

int HTMLImageElement::y() const
{
    RenderObject* r = renderer();
    if (!r)
        return 0;

    // FIXME: This doesn't work correctly with transforms.
    FloatPoint absPos = r->localToAbsolute();
    return absPos.y();
}

bool HTMLImageElement::complete() const
{
    return m_imageLoader.imageComplete();
}

void HTMLImageElement::addSubresourceAttributeURLs(ListHashSet<KURL>& urls) const
{
    HTMLElement::addSubresourceAttributeURLs(urls);

    addSubresourceURL(urls, src());
    addSubresourceURL(urls, document()->completeURL(useMap()));
}

}