/*
    Copyright (C) 2004, 2005, 2006, 2007, 2008 Nikolas Zimmermann <zimmermann@kde.org>
                  2004, 2005, 2006, 2007 Rob Buis <buis@kde.org>

    This file is part of the KDE project

    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.
*/

#if ENABLE(SVG)
#include "SVGPatternElement.h"

#include "AffineTransform.h"
#include "Document.h"
#include "FloatConversion.h"
#include "GraphicsContext.h"
#include "ImageBuffer.h"
#include "PatternAttributes.h"
#include "RenderSVGContainer.h"
#include "SVGLength.h"
#include "SVGNames.h"
#include "SVGRenderSupport.h"
#include "SVGStyledTransformableElement.h"
#include "SVGSVGElement.h"
#include "SVGTransformList.h"
#include "SVGTransformable.h"
#include "SVGUnitTypes.h"

#include <math.h>
#include <wtf/OwnPtr.h>
#include <wtf/MathExtras.h>

using namespace std;

namespace WebCore
{

SVGPatternElement::SVGPatternElement(const QualifiedName &tagName, Document *doc)
    : SVGStyledElement(tagName, doc)
    , SVGURIReference()
    , SVGTests()
    , SVGLangSpace()
    , SVGExternalResourcesRequired()
    , SVGFitToViewBox()
    , m_x(this, LengthModeWidth)
    , m_y(this, LengthModeHeight)
    , m_width(this, LengthModeWidth)
    , m_height(this, LengthModeHeight)
    , m_patternUnits(SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX)
    , m_patternContentUnits(SVGUnitTypes::SVG_UNIT_TYPE_USERSPACEONUSE)
    , m_patternTransform(SVGTransformList::create(SVGNames::patternTransformAttr))
{
}

SVGPatternElement::~SVGPatternElement()
{
}

ANIMATED_PROPERTY_DEFINITIONS(SVGPatternElement, int, Enumeration, enumeration, PatternUnits, patternUnits, SVGNames::patternUnitsAttr, m_patternUnits)
ANIMATED_PROPERTY_DEFINITIONS(SVGPatternElement, int, Enumeration, enumeration, PatternContentUnits, patternContentUnits, SVGNames::patternContentUnitsAttr, m_patternContentUnits)
ANIMATED_PROPERTY_DEFINITIONS(SVGPatternElement, SVGLength, Length, length, X, x, SVGNames::xAttr, m_x)
ANIMATED_PROPERTY_DEFINITIONS(SVGPatternElement, SVGLength, Length, length, Y, y, SVGNames::yAttr, m_y)
ANIMATED_PROPERTY_DEFINITIONS(SVGPatternElement, SVGLength, Length, length, Width, width, SVGNames::widthAttr, m_width)
ANIMATED_PROPERTY_DEFINITIONS(SVGPatternElement, SVGLength, Length, length, Height, height, SVGNames::heightAttr, m_height)
ANIMATED_PROPERTY_DEFINITIONS(SVGPatternElement, SVGTransformList *, TransformList, transformList, PatternTransform, patternTransform, SVGNames::patternTransformAttr, m_patternTransform.get())

void SVGPatternElement::parseMappedAttribute(MappedAttribute *attr)
{
    if (attr->name() == SVGNames::patternUnitsAttr) {
        if (attr->value() == "userSpaceOnUse") {
            setPatternUnitsBaseValue(SVGUnitTypes::SVG_UNIT_TYPE_USERSPACEONUSE);
        } else if (attr->value() == "objectBoundingBox") {
            setPatternUnitsBaseValue(SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX);
        }
    } else if (attr->name() == SVGNames::patternContentUnitsAttr) {
        if (attr->value() == "userSpaceOnUse") {
            setPatternContentUnitsBaseValue(SVGUnitTypes::SVG_UNIT_TYPE_USERSPACEONUSE);
        } else if (attr->value() == "objectBoundingBox") {
            setPatternContentUnitsBaseValue(SVGUnitTypes::SVG_UNIT_TYPE_OBJECTBOUNDINGBOX);
        }
    } else if (attr->name() == SVGNames::patternTransformAttr) {
        SVGTransformList *patternTransforms = patternTransformBaseValue();
        if (!SVGTransformable::parseTransformAttribute(patternTransforms, attr->value())) {
            ExceptionCode ec = 0;
            patternTransforms->clear(ec);
        }
    } else if (attr->name() == SVGNames::xAttr) {
        setXBaseValue(SVGLength(this, LengthModeWidth, attr->value()));
    } else if (attr->name() == SVGNames::yAttr) {
        setYBaseValue(SVGLength(this, LengthModeHeight, attr->value()));
    } else if (attr->name() == SVGNames::widthAttr) {
        setWidthBaseValue(SVGLength(this, LengthModeWidth, attr->value()));
        if (width().value() < 0.0) {
            document()->accessSVGExtensions()->reportError("A negative value for pattern attribute <width> is not allowed");
        }
    } else if (attr->name() == SVGNames::heightAttr) {
        setHeightBaseValue(SVGLength(this, LengthModeHeight, attr->value()));
        if (width().value() < 0.0) {
            document()->accessSVGExtensions()->reportError("A negative value for pattern attribute <height> is not allowed");
        }
    } else {
        if (SVGURIReference::parseMappedAttribute(attr)) {
            return;
        }
        if (SVGTests::parseMappedAttribute(attr)) {
            return;
        }
        if (SVGLangSpace::parseMappedAttribute(attr)) {
            return;
        }
        if (SVGExternalResourcesRequired::parseMappedAttribute(attr)) {
            return;
        }
        if (SVGFitToViewBox::parseMappedAttribute(attr)) {
            return;
        }

        SVGStyledElement::parseMappedAttribute(attr);
    }
}

void SVGPatternElement::svgAttributeChanged(const QualifiedName &attrName)
{
    SVGStyledElement::svgAttributeChanged(attrName);

    if (!m_resource) {
        return;
    }

    if (attrName == SVGNames::patternUnitsAttr || attrName == SVGNames::patternContentUnitsAttr ||
            attrName == SVGNames::patternTransformAttr || attrName == SVGNames::xAttr || attrName == SVGNames::yAttr ||
            attrName == SVGNames::widthAttr || attrName == SVGNames::heightAttr ||
            SVGURIReference::isKnownAttribute(attrName) ||
            SVGTests::isKnownAttribute(attrName) ||
            SVGLangSpace::isKnownAttribute(attrName) ||
            SVGExternalResourcesRequired::isKnownAttribute(attrName) ||
            SVGFitToViewBox::isKnownAttribute(attrName) ||
            SVGStyledElement::isKnownAttribute(attrName)) {
        m_resource->invalidate();
    }
}

void SVGPatternElement::childrenChanged(bool changedByParser, Node *beforeChange, Node *afterChange, int childCountDelta)
{
    SVGStyledElement::childrenChanged(changedByParser, beforeChange, afterChange, childCountDelta);

    if (!m_resource) {
        return;
    }

    m_resource->invalidate();
}

void SVGPatternElement::buildPattern(const FloatRect &targetRect) const
{
    PatternAttributes attributes = collectPatternProperties();

    // If we didn't find any pattern content, ignore the request.
    if (!attributes.patternContentElement() || !renderer() || !renderer()->style()) {
        return;
    }

    FloatRect patternBoundaries;
    FloatRect patternContentBoundaries;

    // Determine specified pattern size
    if (attributes.boundingBoxMode())
        patternBoundaries = FloatRect(attributes.x().valueAsPercentage() * targetRect.width(),
                                      attributes.y().valueAsPercentage() * targetRect.height(),
                                      attributes.width().valueAsPercentage() * targetRect.width(),
                                      attributes.height().valueAsPercentage() * targetRect.height());
    else
        patternBoundaries = FloatRect(attributes.x().value(),
                                      attributes.y().value(),
                                      attributes.width().value(),
                                      attributes.height().value());

    // Clip pattern boundaries to target boundaries
    if (patternBoundaries.width() > targetRect.width()) {
        patternBoundaries.setWidth(targetRect.width());
    }

    if (patternBoundaries.height() > targetRect.height()) {
        patternBoundaries.setHeight(targetRect.height());
    }

    IntSize patternSize(patternBoundaries.width(), patternBoundaries.height());
    clampImageBufferSizeToViewport(document()->renderer(), patternSize);

    if (patternSize.width() < static_cast<int>(patternBoundaries.width())) {
        patternBoundaries.setWidth(patternSize.width());
    }

    if (patternSize.height() < static_cast<int>(patternBoundaries.height())) {
        patternBoundaries.setHeight(patternSize.height());
    }

    // Eventually calculate the pattern content boundaries (only needed with overflow="visible").
    RenderStyle *style = renderer()->style();
    if (style->overflowX() == OVISIBLE && style->overflowY() == OVISIBLE) {
        for (Node *n = attributes.patternContentElement()->firstChild(); n; n = n->nextSibling()) {
            if (!n->isSVGElement() || !static_cast<SVGElement *>(n)->isStyledTransformable() || !n->renderer()) {
                continue;
            }
            patternContentBoundaries.unite(n->renderer()->relativeBBox(true));
        }
    }

    AffineTransform viewBoxCTM = viewBoxToViewTransform(patternBoundaries.width(), patternBoundaries.height());
    FloatRect patternBoundariesIncludingOverflow = patternBoundaries;

    // Apply objectBoundingBoxMode fixup for patternContentUnits, if viewBox is not set.
    if (!patternContentBoundaries.isEmpty()) {
        if (!viewBoxCTM.isIdentity()) {
            patternContentBoundaries = viewBoxCTM.mapRect(patternContentBoundaries);
        } else if (attributes.boundingBoxModeContent())
            patternContentBoundaries = FloatRect(patternContentBoundaries.x() * targetRect.width(),
                                                 patternContentBoundaries.y() * targetRect.height(),
                                                 patternContentBoundaries.width() * targetRect.width(),
                                                 patternContentBoundaries.height() * targetRect.height());

        patternBoundariesIncludingOverflow.unite(patternContentBoundaries);
    }

    IntSize imageSize(lroundf(patternBoundariesIncludingOverflow.width()), lroundf(patternBoundariesIncludingOverflow.height()));
    clampImageBufferSizeToViewport(document()->renderer(), imageSize);

    unique_ptr<ImageBuffer> patternImage = ImageBuffer::create(imageSize, false);

    if (!patternImage.get()) {
        return;
    }

    GraphicsContext *context = patternImage->context();
    ASSERT(context);

    context->save();

    // Move to pattern start origin
    if (patternBoundariesIncludingOverflow.location() != patternBoundaries.location()) {
        context->translate(patternBoundaries.x() - patternBoundariesIncludingOverflow.x(),
                           patternBoundaries.y() - patternBoundariesIncludingOverflow.y());

        patternBoundaries.setLocation(patternBoundariesIncludingOverflow.location());
    }

    // Process viewBox or boundingBoxModeContent correction
    if (!viewBoxCTM.isIdentity()) {
        context->concatCTM(viewBoxCTM);
    } else if (attributes.boundingBoxModeContent()) {
        context->translate(targetRect.x(), targetRect.y());
        context->scale(FloatSize(targetRect.width(), targetRect.height()));
    }

    // Render subtree into ImageBuffer
    for (Node *n = attributes.patternContentElement()->firstChild(); n; n = n->nextSibling()) {
        if (!n->isSVGElement() || !static_cast<SVGElement *>(n)->isStyled() || !n->renderer()) {
            continue;
        }
        renderSubtreeToImage(patternImage.get(), n->renderer());
    }

    context->restore();

    m_resource->setPatternTransform(attributes.patternTransform());
    m_resource->setPatternBoundaries(patternBoundaries);
    m_resource->setTile(patternImage);
}

RenderObject *SVGPatternElement::createRenderer(RenderArena *arena, RenderStyle *)
{
    RenderSVGContainer *patternContainer = new(arena) RenderSVGContainer(this);
    patternContainer->setDrawsContents(false);
    return patternContainer;
}

SVGResource *SVGPatternElement::canvasResource()
{
    if (!m_resource) {
        m_resource = SVGPaintServerPattern::create(this);
    }

    return m_resource.get();
}

PatternAttributes SVGPatternElement::collectPatternProperties() const
{
    PatternAttributes attributes;
    HashSet<const SVGPatternElement *> processedPatterns;

    const SVGPatternElement *current = this;
    while (current) {
        if (!attributes.hasX() && current->hasAttribute(SVGNames::xAttr)) {
            attributes.setX(current->x());
        }

        if (!attributes.hasY() && current->hasAttribute(SVGNames::yAttr)) {
            attributes.setY(current->y());
        }

        if (!attributes.hasWidth() && current->hasAttribute(SVGNames::widthAttr)) {
            attributes.setWidth(current->width());
        }

        if (!attributes.hasHeight() && current->hasAttribute(SVGNames::heightAttr)) {
            attributes.setHeight(current->height());
        }

        if (!attributes.hasBoundingBoxMode() && current->hasAttribute(SVGNames::patternUnitsAttr)) {
            attributes.setBoundingBoxMode(current->getAttribute(SVGNames::patternUnitsAttr) == "objectBoundingBox");
        }

        if (!attributes.hasBoundingBoxModeContent() && current->hasAttribute(SVGNames::patternContentUnitsAttr)) {
            attributes.setBoundingBoxModeContent(current->getAttribute(SVGNames::patternContentUnitsAttr) == "objectBoundingBox");
        }

        if (!attributes.hasPatternTransform() && current->hasAttribute(SVGNames::patternTransformAttr)) {
            attributes.setPatternTransform(current->patternTransform()->consolidate().matrix());
        }

        if (!attributes.hasPatternContentElement() && current->hasChildNodes()) {
            attributes.setPatternContentElement(current);
        }

        processedPatterns.add(current);

        // Respect xlink:href, take attributes from referenced element
        Node *refNode = ownerDocument()->getElementById(SVGURIReference::getTarget(current->href()));
        if (refNode && refNode->hasTagName(SVGNames::patternTag)) {
            current = static_cast<const SVGPatternElement *>(const_cast<const Node *>(refNode));

            // Cycle detection
            if (processedPatterns.contains(current)) {
                return PatternAttributes();
            }
        } else {
            current = 0;
        }
    }

    return attributes;
}

}

#endif // ENABLE(SVG)
