/*
 * Copyright (C) 2004, 2005, 2006, 2008 Nikolas Zimmermann <zimmermann@kde.org>
 * Copyright (C) 2004, 2005, 2006, 2007 Rob Buis <buis@kde.org>
 * Copyright (C) 2008 Eric Seidel <eric@webkit.org>
 * Copyright (C) 2008 Dirk Schulze <krit@webkit.org>
 * Copyright (C) Research In Motion Limited 2010. 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 "core/svg/SVGRadialGradientElement.h"

#include "SVGNames.h"
#include "core/rendering/svg/RenderSVGResourceRadialGradient.h"
#include "core/svg/RadialGradientAttributes.h"
#include "core/svg/SVGElementInstance.h"
#include "core/svg/SVGTransformList.h"

namespace WebCore {

// Animated property definitions
DEFINE_ANIMATED_LENGTH(SVGRadialGradientElement, SVGNames::cxAttr, Cx, cx)
DEFINE_ANIMATED_LENGTH(SVGRadialGradientElement, SVGNames::cyAttr, Cy, cy)
DEFINE_ANIMATED_LENGTH(SVGRadialGradientElement, SVGNames::rAttr, R, r)
DEFINE_ANIMATED_LENGTH(SVGRadialGradientElement, SVGNames::fxAttr, Fx, fx)
DEFINE_ANIMATED_LENGTH(SVGRadialGradientElement, SVGNames::fyAttr, Fy, fy)
DEFINE_ANIMATED_LENGTH(SVGRadialGradientElement, SVGNames::frAttr, Fr, fr)

BEGIN_REGISTER_ANIMATED_PROPERTIES(SVGRadialGradientElement)
    REGISTER_LOCAL_ANIMATED_PROPERTY(cx)
    REGISTER_LOCAL_ANIMATED_PROPERTY(cy)
    REGISTER_LOCAL_ANIMATED_PROPERTY(r)
    REGISTER_LOCAL_ANIMATED_PROPERTY(fx)
    REGISTER_LOCAL_ANIMATED_PROPERTY(fy)
    REGISTER_LOCAL_ANIMATED_PROPERTY(fr)
    REGISTER_PARENT_ANIMATED_PROPERTIES(SVGGradientElement)
END_REGISTER_ANIMATED_PROPERTIES

inline SVGRadialGradientElement::SVGRadialGradientElement(const QualifiedName& tagName, Document& document)
    : SVGGradientElement(tagName, document)
    , m_cx(LengthModeWidth, "50%")
    , m_cy(LengthModeHeight, "50%")
    , m_r(LengthModeOther, "50%")
    , m_fx(LengthModeWidth)
    , m_fy(LengthModeHeight)
    , m_fr(LengthModeOther, "0%")
{
    // Spec: If the cx/cy/r/fr attribute is not specified, the effect is as if a value of "50%" were specified.
    ASSERT(hasTagName(SVGNames::radialGradientTag));
    ScriptWrappable::init(this);
    registerAnimatedPropertiesForSVGRadialGradientElement();
}

PassRefPtr<SVGRadialGradientElement> SVGRadialGradientElement::create(const QualifiedName& tagName, Document& document)
{
    return adoptRef(new SVGRadialGradientElement(tagName, document));
}

bool SVGRadialGradientElement::isSupportedAttribute(const QualifiedName& attrName)
{
    DEFINE_STATIC_LOCAL(HashSet<QualifiedName>, supportedAttributes, ());
    if (supportedAttributes.isEmpty()) {
        supportedAttributes.add(SVGNames::cxAttr);
        supportedAttributes.add(SVGNames::cyAttr);
        supportedAttributes.add(SVGNames::fxAttr);
        supportedAttributes.add(SVGNames::fyAttr);
        supportedAttributes.add(SVGNames::rAttr);
        supportedAttributes.add(SVGNames::frAttr);
    }
    return supportedAttributes.contains<SVGAttributeHashTranslator>(attrName);
}

void SVGRadialGradientElement::parseAttribute(const QualifiedName& name, const AtomicString& value)
{
    SVGParsingError parseError = NoError;

    if (!isSupportedAttribute(name))
        SVGGradientElement::parseAttribute(name, value);
    else if (name == SVGNames::cxAttr)
        setCxBaseValue(SVGLength::construct(LengthModeWidth, value, parseError));
    else if (name == SVGNames::cyAttr)
        setCyBaseValue(SVGLength::construct(LengthModeHeight, value, parseError));
    else if (name == SVGNames::rAttr)
        setRBaseValue(SVGLength::construct(LengthModeOther, value, parseError, ForbidNegativeLengths));
    else if (name == SVGNames::fxAttr)
        setFxBaseValue(SVGLength::construct(LengthModeWidth, value, parseError));
    else if (name == SVGNames::fyAttr)
        setFyBaseValue(SVGLength::construct(LengthModeHeight, value, parseError));
    else if (name == SVGNames::frAttr)
        setFrBaseValue(SVGLength::construct(LengthModeOther, value, parseError, ForbidNegativeLengths));
    else
        ASSERT_NOT_REACHED();

    reportAttributeParsingError(parseError, name, value);
}

void SVGRadialGradientElement::svgAttributeChanged(const QualifiedName& attrName)
{
    if (!isSupportedAttribute(attrName)) {
        SVGGradientElement::svgAttributeChanged(attrName);
        return;
    }

    SVGElementInstance::InvalidationGuard invalidationGuard(this);

    updateRelativeLengthsInformation();

    if (RenderObject* object = renderer())
        object->setNeedsLayout();
}

RenderObject* SVGRadialGradientElement::createRenderer(RenderStyle*)
{
    return new RenderSVGResourceRadialGradient(this);
}

bool SVGRadialGradientElement::collectGradientAttributes(RadialGradientAttributes& attributes)
{
    HashSet<SVGGradientElement*> processedGradients;

    bool isRadial = true;
    SVGGradientElement* current = this;

    while (current) {
        if (!current->renderer())
            return false;

        if (!attributes.hasSpreadMethod() && current->hasAttribute(SVGNames::spreadMethodAttr))
            attributes.setSpreadMethod(current->spreadMethodCurrentValue());

        if (!attributes.hasGradientUnits() && current->hasAttribute(SVGNames::gradientUnitsAttr))
            attributes.setGradientUnits(current->gradientUnitsCurrentValue());

        if (!attributes.hasGradientTransform() && current->hasAttribute(SVGNames::gradientTransformAttr)) {
            AffineTransform transform;
            current->gradientTransformCurrentValue().concatenate(transform);
            attributes.setGradientTransform(transform);
        }

        if (!attributes.hasStops()) {
            const Vector<Gradient::ColorStop>& stops(current->buildStops());
            if (!stops.isEmpty())
                attributes.setStops(stops);
        }

        if (isRadial) {
            SVGRadialGradientElement* radial = toSVGRadialGradientElement(current);

            if (!attributes.hasCx() && current->hasAttribute(SVGNames::cxAttr))
                attributes.setCx(radial->cxCurrentValue());

            if (!attributes.hasCy() && current->hasAttribute(SVGNames::cyAttr))
                attributes.setCy(radial->cyCurrentValue());

            if (!attributes.hasR() && current->hasAttribute(SVGNames::rAttr))
                attributes.setR(radial->rCurrentValue());

            if (!attributes.hasFx() && current->hasAttribute(SVGNames::fxAttr))
                attributes.setFx(radial->fxCurrentValue());

            if (!attributes.hasFy() && current->hasAttribute(SVGNames::fyAttr))
                attributes.setFy(radial->fyCurrentValue());

            if (!attributes.hasFr() && current->hasAttribute(SVGNames::frAttr))
                attributes.setFr(radial->frCurrentValue());
        }

        processedGradients.add(current);

        // Respect xlink:href, take attributes from referenced element
        Node* refNode = SVGURIReference::targetElementFromIRIString(current->hrefCurrentValue(), document());
        if (refNode && (refNode->hasTagName(SVGNames::radialGradientTag) || refNode->hasTagName(SVGNames::linearGradientTag))) {
            current = toSVGGradientElement(refNode);

            // Cycle detection
            if (processedGradients.contains(current)) {
                current = 0;
                break;
            }

            isRadial = current->hasTagName(SVGNames::radialGradientTag);
        } else
            current = 0;
    }

    // Handle default values for fx/fy
    if (!attributes.hasFx())
        attributes.setFx(attributes.cx());

    if (!attributes.hasFy())
        attributes.setFy(attributes.cy());
    return true;
}

bool SVGRadialGradientElement::selfHasRelativeLengths() const
{
    return cxCurrentValue().isRelative()
        || cyCurrentValue().isRelative()
        || rCurrentValue().isRelative()
        || fxCurrentValue().isRelative()
        || fyCurrentValue().isRelative()
        || frCurrentValue().isRelative();
}

}
