/*
 * Copyright (C) 2007 Apple Inc. All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1.  Redistributions of source code must retain the above copyright
 *     notice, this list of conditions and the following disclaimer. 
 * 2.  Redistributions in binary form must reproduce the above copyright
 *     notice, this list of conditions and the following disclaimer in the
 *     documentation and/or other materials provided with the distribution. 
 * 3.  Neither the name of Apple Computer, Inc. ("Apple") nor the names of
 *     its contributors may be used to endorse or promote products derived
 *     from this software without specific prior written permission. 
 *
 * THIS SOFTWARE IS PROVIDED BY APPLE AND ITS CONTRIBUTORS "AS IS" AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL APPLE OR ITS CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "config.h"
#include "CompositeAnimation.h"

#include "AnimationControllerPrivate.h"
#include "CSSPropertyAnimation.h"
#include "CSSPropertyNames.h"
#include "ImplicitAnimation.h"
#include "KeyframeAnimation.h"
#include "Logging.h"
#include "RenderObject.h"
#include "RenderStyle.h"
#include <wtf/text/CString.h>

namespace WebCore {

CompositeAnimation::CompositeAnimation(AnimationControllerPrivate* animationController)
    : m_animationController(animationController)
{
    m_suspended = animationController->isSuspended();
}

CompositeAnimation::~CompositeAnimation()
{
    // Toss the refs to all animations, but make sure we remove them from
    // any waiting lists first.

    clearRenderer();
    m_transitions.clear();
    m_keyframeAnimations.clear();
}

void CompositeAnimation::clearRenderer()
{
    if (!m_transitions.isEmpty()) {
        // Clear the renderers from all running animations, in case we are in the middle of
        // an animation callback (see https://bugs.webkit.org/show_bug.cgi?id=22052)
        CSSPropertyTransitionsMap::const_iterator transitionsEnd = m_transitions.end();
        for (CSSPropertyTransitionsMap::const_iterator it = m_transitions.begin(); it != transitionsEnd; ++it) {
            ImplicitAnimation* transition = it->value.get();
            animationController()->animationWillBeRemoved(transition);
            transition->clear();
        }
    }
    if (!m_keyframeAnimations.isEmpty()) {
        m_keyframeAnimations.checkConsistency();
        AnimationNameMap::const_iterator animationsEnd = m_keyframeAnimations.end();
        for (AnimationNameMap::const_iterator it = m_keyframeAnimations.begin(); it != animationsEnd; ++it) {
            KeyframeAnimation* anim = it->value.get();
            animationController()->animationWillBeRemoved(anim);
            anim->clear();
        }
    }
}

void CompositeAnimation::updateTransitions(RenderObject* renderer, RenderStyle* currentStyle, RenderStyle* targetStyle)
{
    // If currentStyle is null or there are no old or new transitions, just skip it
    if (!currentStyle || (!targetStyle->transitions() && m_transitions.isEmpty()))
        return;

    // Mark all existing transitions as no longer active. We will mark the still active ones
    // in the next loop and then toss the ones that didn't get marked.
    CSSPropertyTransitionsMap::const_iterator end = m_transitions.end();
    for (CSSPropertyTransitionsMap::const_iterator it = m_transitions.begin(); it != end; ++it)
        it->value->setActive(false);
        
    RefPtr<RenderStyle> modifiedCurrentStyle;
    
    // Check to see if we need to update the active transitions
    if (targetStyle->transitions()) {
        for (size_t i = 0; i < targetStyle->transitions()->size(); ++i) {
            const Animation* anim = targetStyle->transitions()->animation(i);
            bool isActiveTransition = !m_suspended && (anim->duration() || anim->delay() > 0);

            Animation::AnimationMode mode = anim->animationMode();
            if (mode == Animation::AnimateNone)
                continue;

            CSSPropertyID prop = anim->property();

            bool all = mode == Animation::AnimateAll;

            // Handle both the 'all' and single property cases. For the single prop case, we make only one pass
            // through the loop.
            for (int propertyIndex = 0; propertyIndex < CSSPropertyAnimation::getNumProperties(); ++propertyIndex) {
                if (all) {
                    // Get the next property which is not a shorthand.
                    bool isShorthand;
                    prop = CSSPropertyAnimation::getPropertyAtIndex(propertyIndex, isShorthand);
                    if (isShorthand)
                        continue;
                }

                // ImplicitAnimations are always hashed by actual properties, never animateAll.
                ASSERT(prop >= firstCSSProperty && prop < (firstCSSProperty + numCSSProperties));

                // If there is a running animation for this property, the transition is overridden
                // and we have to use the unanimatedStyle from the animation. We do the test
                // against the unanimated style here, but we "override" the transition later.
                RefPtr<KeyframeAnimation> keyframeAnim = getAnimationForProperty(prop);
                RenderStyle* fromStyle = keyframeAnim ? keyframeAnim->unanimatedStyle() : currentStyle;

                // See if there is a current transition for this prop
                ImplicitAnimation* implAnim = m_transitions.get(prop);
                bool equal = true;

                if (implAnim) {
                    // If we are post active don't bother setting the active flag. This will cause
                    // this animation to get removed at the end of this function.
                    if (!implAnim->postActive())
                        implAnim->setActive(true);
                    
                    // This might be a transition that is just finishing. That would be the case
                    // if it were postActive. But we still need to check for equality because
                    // it could be just finishing AND changing to a new goal state.
                    //
                    // This implAnim might also not be an already running transition. It might be
                    // newly added to the list in a previous iteration. This would happen if
                    // you have both an explicit transition-property and 'all' in the same
                    // list. In this case, the latter one overrides the earlier one, so we
                    // behave as though this is a running animation being replaced.
                    if (!implAnim->isTargetPropertyEqual(prop, targetStyle)) {
    #if USE(ACCELERATED_COMPOSITING)
                        // For accelerated animations we need to return a new RenderStyle with the _current_ value
                        // of the property, so that restarted transitions use the correct starting point.
                        if (CSSPropertyAnimation::animationOfPropertyIsAccelerated(prop) && implAnim->isAccelerated()) {
                            if (!modifiedCurrentStyle)
                                modifiedCurrentStyle = RenderStyle::clone(currentStyle);

                            implAnim->blendPropertyValueInStyle(prop, modifiedCurrentStyle.get());
                        }
    #endif
                        LOG(Animations, "Removing existing ImplicitAnimation %p for property %s", implAnim, getPropertyName(prop));
                        animationController()->animationWillBeRemoved(implAnim);
                        m_transitions.remove(prop);
                        equal = false;
                    }
                } else {
                    // We need to start a transition if it is active and the properties don't match
                    equal = !isActiveTransition || CSSPropertyAnimation::propertiesEqual(prop, fromStyle, targetStyle);
                }

                // We can be in this loop with an inactive transition (!isActiveTransition). We need
                // to do that to check to see if we are canceling a transition. But we don't want to
                // start one of the inactive transitions. So short circuit that here. (See
                // <https://bugs.webkit.org/show_bug.cgi?id=24787>
                if (!equal && isActiveTransition) {
                    // Add the new transition
                    RefPtr<ImplicitAnimation> animation = ImplicitAnimation::create(const_cast<Animation*>(anim), prop, renderer, this, modifiedCurrentStyle ? modifiedCurrentStyle.get() : fromStyle);
                    LOG(Animations, "Created ImplicitAnimation %p for property %s duration %.2f delay %.2f", animation.get(), getPropertyName(prop), anim->duration(), anim->delay());
                    m_transitions.set(prop, animation.release());
                }
                
                // We only need one pass for the single prop case
                if (!all)
                    break;
            }
        }
    }

    // Make a list of transitions to be removed
    Vector<int> toBeRemoved;
    end = m_transitions.end();
    for (CSSPropertyTransitionsMap::const_iterator it = m_transitions.begin(); it != end; ++it) {
        ImplicitAnimation* anim = it->value.get();
        if (!anim->active()) {
            animationController()->animationWillBeRemoved(anim);
            toBeRemoved.append(anim->animatingProperty());
            LOG(Animations, "Removing ImplicitAnimation %p for property %s", anim, getPropertyName(anim->animatingProperty()));
        }
    }

    // Now remove the transitions from the list
    for (size_t j = 0; j < toBeRemoved.size(); ++j)
        m_transitions.remove(toBeRemoved[j]);
}

void CompositeAnimation::updateKeyframeAnimations(RenderObject* renderer, RenderStyle* currentStyle, RenderStyle* targetStyle)
{
    // Nothing to do if we don't have any animations, and didn't have any before
    if (m_keyframeAnimations.isEmpty() && !targetStyle->hasAnimations())
        return;

    m_keyframeAnimations.checkConsistency();

    AnimationNameMap::const_iterator kfend = m_keyframeAnimations.end();
    
    if (currentStyle && currentStyle->hasAnimations() && targetStyle->hasAnimations() && *(currentStyle->animations()) == *(targetStyle->animations())) {
        // The current and target animations are the same so we just need to toss any 
        // animation which is finished (postActive).
        for (AnimationNameMap::const_iterator it = m_keyframeAnimations.begin(); it != kfend; ++it) {
            if (it->value->postActive())
                it->value->setIndex(-1);
        }
    } else {
        // Mark all existing animations as no longer active.
        for (AnimationNameMap::const_iterator it = m_keyframeAnimations.begin(); it != kfend; ++it)
            it->value->setIndex(-1);
            
        // Toss the animation order map.
        m_keyframeAnimationOrderMap.clear();

        DEFINE_STATIC_LOCAL(const AtomicString, none, ("none", AtomicString::ConstructFromLiteral));
        
        // Now mark any still active animations as active and add any new animations.
        if (targetStyle->animations()) {
            int numAnims = targetStyle->animations()->size();
            for (int i = 0; i < numAnims; ++i) {
                const Animation* anim = targetStyle->animations()->animation(i);
                AtomicString animationName(anim->name());

                if (!anim->isValidAnimation())
                    continue;
                
                // See if there is a current animation for this name.
                RefPtr<KeyframeAnimation> keyframeAnim = m_keyframeAnimations.get(animationName.impl());
                
                if (keyframeAnim) {
                    // If this animation is postActive, skip it so it gets removed at the end of this function.
                    if (keyframeAnim->postActive())
                        continue;
                    
                    // This one is still active.

                    // Animations match, but play states may differ. Update if needed.
                    keyframeAnim->updatePlayState(anim->playState());
                                
                    // Set the saved animation to this new one, just in case the play state has changed.
                    keyframeAnim->setAnimation(anim);
                    keyframeAnim->setIndex(i);
                } else if ((anim->duration() || anim->delay()) && anim->iterationCount() && animationName != none) {
                    keyframeAnim = KeyframeAnimation::create(const_cast<Animation*>(anim), renderer, i, this, targetStyle);
                    LOG(Animations, "Creating KeyframeAnimation %p with keyframes %s, duration %.2f, delay %.2f, iterations %.2f", keyframeAnim.get(), anim->name().utf8().data(), anim->duration(), anim->delay(), anim->iterationCount());
                    if (m_suspended) {
                        keyframeAnim->updatePlayState(AnimPlayStatePaused);
                        LOG(Animations, "  (created in suspended/paused state)");
                    }
#if !LOG_DISABLED
                    HashSet<CSSPropertyID>::const_iterator endProperties = keyframeAnim->keyframes().endProperties();
                    for (HashSet<CSSPropertyID>::const_iterator it = keyframeAnim->keyframes().beginProperties(); it != endProperties; ++it)
                        LOG(Animations, "  property %s", getPropertyName(*it));
#endif
                    m_keyframeAnimations.set(keyframeAnim->name().impl(), keyframeAnim);
                }
                
                // Add this to the animation order map.
                if (keyframeAnim)
                    m_keyframeAnimationOrderMap.append(keyframeAnim->name().impl());
            }
        }
    }
    
    // Make a list of animations to be removed.
    Vector<AtomicStringImpl*> animsToBeRemoved;
    kfend = m_keyframeAnimations.end();
    for (AnimationNameMap::const_iterator it = m_keyframeAnimations.begin(); it != kfend; ++it) {
        KeyframeAnimation* keyframeAnim = it->value.get();
        if (keyframeAnim->index() < 0) {
            animsToBeRemoved.append(keyframeAnim->name().impl());
            animationController()->animationWillBeRemoved(keyframeAnim);
            keyframeAnim->clear();
            LOG(Animations, "Removing KeyframeAnimation %p", keyframeAnim);
        }
    }
    
    // Now remove the animations from the list.
    for (size_t j = 0; j < animsToBeRemoved.size(); ++j)
        m_keyframeAnimations.remove(animsToBeRemoved[j]);
}

PassRefPtr<RenderStyle> CompositeAnimation::animate(RenderObject* renderer, RenderStyle* currentStyle, RenderStyle* targetStyle)
{
    RefPtr<RenderStyle> resultStyle;

    // We don't do any transitions if we don't have a currentStyle (on startup).
    updateTransitions(renderer, currentStyle, targetStyle);
    updateKeyframeAnimations(renderer, currentStyle, targetStyle);
    m_keyframeAnimations.checkConsistency();

    if (currentStyle) {
        // Now that we have transition objects ready, let them know about the new goal state.  We want them
        // to fill in a RenderStyle*& only if needed.
        if (!m_transitions.isEmpty()) {
            CSSPropertyTransitionsMap::const_iterator end = m_transitions.end();
            for (CSSPropertyTransitionsMap::const_iterator it = m_transitions.begin(); it != end; ++it) {
                if (ImplicitAnimation* anim = it->value.get())
                    anim->animate(this, renderer, currentStyle, targetStyle, resultStyle);
            }
        }
    }

    // Now that we have animation objects ready, let them know about the new goal state.  We want them
    // to fill in a RenderStyle*& only if needed.
    for (Vector<AtomicStringImpl*>::const_iterator it = m_keyframeAnimationOrderMap.begin(); it != m_keyframeAnimationOrderMap.end(); ++it) {
        RefPtr<KeyframeAnimation> keyframeAnim = m_keyframeAnimations.get(*it);
        if (keyframeAnim)
            keyframeAnim->animate(this, renderer, currentStyle, targetStyle, resultStyle);
    }

    return resultStyle ? resultStyle.release() : targetStyle;
}

PassRefPtr<RenderStyle> CompositeAnimation::getAnimatedStyle() const
{
    RefPtr<RenderStyle> resultStyle;
    CSSPropertyTransitionsMap::const_iterator end = m_transitions.end();
    for (CSSPropertyTransitionsMap::const_iterator it = m_transitions.begin(); it != end; ++it) {
        if (ImplicitAnimation* implicitAnimation = it->value.get())
            implicitAnimation->getAnimatedStyle(resultStyle);
    }

    m_keyframeAnimations.checkConsistency();

    for (Vector<AtomicStringImpl*>::const_iterator it = m_keyframeAnimationOrderMap.begin(); it != m_keyframeAnimationOrderMap.end(); ++it) {
        RefPtr<KeyframeAnimation> keyframeAnimation = m_keyframeAnimations.get(*it);
        if (keyframeAnimation)
            keyframeAnimation->getAnimatedStyle(resultStyle);
    }
    
    return resultStyle;
}

double CompositeAnimation::timeToNextService() const
{
    // Returns the time at which next service is required. -1 means no service is required. 0 means 
    // service is required now, and > 0 means service is required that many seconds in the future.
    double minT = -1;
    
    if (!m_transitions.isEmpty()) {
        CSSPropertyTransitionsMap::const_iterator transitionsEnd = m_transitions.end();
        for (CSSPropertyTransitionsMap::const_iterator it = m_transitions.begin(); it != transitionsEnd; ++it) {
            ImplicitAnimation* transition = it->value.get();
            double t = transition ? transition->timeToNextService() : -1;
            if (t < minT || minT == -1)
                minT = t;
            if (minT == 0)
                return 0;
        }
    }
    if (!m_keyframeAnimations.isEmpty()) {
        m_keyframeAnimations.checkConsistency();
        AnimationNameMap::const_iterator animationsEnd = m_keyframeAnimations.end();
        for (AnimationNameMap::const_iterator it = m_keyframeAnimations.begin(); it != animationsEnd; ++it) {
            KeyframeAnimation* animation = it->value.get();
            double t = animation ? animation->timeToNextService() : -1;
            if (t < minT || minT == -1)
                minT = t;
            if (minT == 0)
                return 0;
        }
    }

    return minT;
}

PassRefPtr<KeyframeAnimation> CompositeAnimation::getAnimationForProperty(CSSPropertyID property) const
{
    RefPtr<KeyframeAnimation> retval;
    
    // We want to send back the last animation with the property if there are multiples.
    // So we need to iterate through all animations
    if (!m_keyframeAnimations.isEmpty()) {
        m_keyframeAnimations.checkConsistency();
        AnimationNameMap::const_iterator animationsEnd = m_keyframeAnimations.end();
        for (AnimationNameMap::const_iterator it = m_keyframeAnimations.begin(); it != animationsEnd; ++it) {
            RefPtr<KeyframeAnimation> anim = it->value;
            if (anim->hasAnimationForProperty(property))
                retval = anim;
        }
    }
    
    return retval;
}

void CompositeAnimation::suspendAnimations()
{
    if (m_suspended)
        return;

    m_suspended = true;

    if (!m_keyframeAnimations.isEmpty()) {
        m_keyframeAnimations.checkConsistency();
        AnimationNameMap::const_iterator animationsEnd = m_keyframeAnimations.end();
        for (AnimationNameMap::const_iterator it = m_keyframeAnimations.begin(); it != animationsEnd; ++it) {
            if (KeyframeAnimation* anim = it->value.get())
                anim->updatePlayState(AnimPlayStatePaused);
        }
    }
    if (!m_transitions.isEmpty()) {
        CSSPropertyTransitionsMap::const_iterator transitionsEnd = m_transitions.end();
        for (CSSPropertyTransitionsMap::const_iterator it = m_transitions.begin(); it != transitionsEnd; ++it) {
            ImplicitAnimation* anim = it->value.get();
            if (anim && anim->hasStyle())
                anim->updatePlayState(AnimPlayStatePaused);
        }
    }
}

void CompositeAnimation::resumeAnimations()
{
    if (!m_suspended)
        return;

    m_suspended = false;

    if (!m_keyframeAnimations.isEmpty()) {
        m_keyframeAnimations.checkConsistency();
        AnimationNameMap::const_iterator animationsEnd = m_keyframeAnimations.end();
        for (AnimationNameMap::const_iterator it = m_keyframeAnimations.begin(); it != animationsEnd; ++it) {
            KeyframeAnimation* anim = it->value.get();
            if (anim && anim->playStatePlaying())
                anim->updatePlayState(AnimPlayStatePlaying);
        }
    }

    if (!m_transitions.isEmpty()) {
        CSSPropertyTransitionsMap::const_iterator transitionsEnd = m_transitions.end();
        for (CSSPropertyTransitionsMap::const_iterator it = m_transitions.begin(); it != transitionsEnd; ++it) {
            ImplicitAnimation* anim = it->value.get();
            if (anim && anim->hasStyle())
                anim->updatePlayState(AnimPlayStatePlaying);
        }
    }
}

void CompositeAnimation::overrideImplicitAnimations(CSSPropertyID property)
{
    CSSPropertyTransitionsMap::const_iterator end = m_transitions.end();
    if (!m_transitions.isEmpty()) {
        for (CSSPropertyTransitionsMap::const_iterator it = m_transitions.begin(); it != end; ++it) {
            ImplicitAnimation* anim = it->value.get();
            if (anim && anim->animatingProperty() == property)
                anim->setOverridden(true);
        }
    }
}

void CompositeAnimation::resumeOverriddenImplicitAnimations(CSSPropertyID property)
{
    if (!m_transitions.isEmpty()) {
        CSSPropertyTransitionsMap::const_iterator end = m_transitions.end();
        for (CSSPropertyTransitionsMap::const_iterator it = m_transitions.begin(); it != end; ++it) {
            ImplicitAnimation* anim = it->value.get();
            if (anim && anim->animatingProperty() == property)
                anim->setOverridden(false);
        }
    }
}

bool CompositeAnimation::isAnimatingProperty(CSSPropertyID property, bool acceleratedOnly, bool isRunningNow) const
{
    if (!m_keyframeAnimations.isEmpty()) {
        m_keyframeAnimations.checkConsistency();
        AnimationNameMap::const_iterator animationsEnd = m_keyframeAnimations.end();
        for (AnimationNameMap::const_iterator it = m_keyframeAnimations.begin(); it != animationsEnd; ++it) {
            KeyframeAnimation* anim = it->value.get();
            if (anim && anim->isAnimatingProperty(property, acceleratedOnly, isRunningNow))
                return true;
        }
    }

    if (!m_transitions.isEmpty()) {
        CSSPropertyTransitionsMap::const_iterator transitionsEnd = m_transitions.end();
        for (CSSPropertyTransitionsMap::const_iterator it = m_transitions.begin(); it != transitionsEnd; ++it) {
            ImplicitAnimation* anim = it->value.get();
            if (anim && anim->isAnimatingProperty(property, acceleratedOnly, isRunningNow))
                return true;
        }
    }
    return false;
}

bool CompositeAnimation::pauseAnimationAtTime(const AtomicString& name, double t)
{
    m_keyframeAnimations.checkConsistency();

    RefPtr<KeyframeAnimation> keyframeAnim = m_keyframeAnimations.get(name.impl());
    if (!keyframeAnim || !keyframeAnim->running())
        return false;

    double count = keyframeAnim->m_animation->iterationCount();
    if ((t >= 0.0) && ((count == Animation::IterationCountInfinite) || (t <= count * keyframeAnim->duration()))) {
        keyframeAnim->freezeAtTime(t);
        return true;
    }

    return false;
}

bool CompositeAnimation::pauseTransitionAtTime(CSSPropertyID property, double t)
{
    if ((property < firstCSSProperty) || (property >= firstCSSProperty + numCSSProperties))
        return false;

    ImplicitAnimation* implAnim = m_transitions.get(property);
    if (!implAnim) {
        // Check to see if this property is being animated via a shorthand.
        // This code is only used for testing, so performance is not critical here.
        HashSet<CSSPropertyID> shorthandProperties = CSSPropertyAnimation::animatableShorthandsAffectingProperty(property);
        bool anyPaused = false;
        HashSet<CSSPropertyID>::const_iterator end = shorthandProperties.end();
        for (HashSet<CSSPropertyID>::const_iterator it = shorthandProperties.begin(); it != end; ++it) {
            if (pauseTransitionAtTime(*it, t))
                anyPaused = true;
        }
        return anyPaused;
    }

    if (!implAnim->running())
        return false;

    if ((t >= 0.0) && (t <= implAnim->duration())) {
        implAnim->freezeAtTime(t);
        return true;
    }

    return false;
}

unsigned CompositeAnimation::numberOfActiveAnimations() const
{
    unsigned count = 0;
    
    if (!m_keyframeAnimations.isEmpty()) {
        m_keyframeAnimations.checkConsistency();
        AnimationNameMap::const_iterator animationsEnd = m_keyframeAnimations.end();
        for (AnimationNameMap::const_iterator it = m_keyframeAnimations.begin(); it != animationsEnd; ++it) {
            KeyframeAnimation* anim = it->value.get();
            if (anim->running())
                ++count;
        }
    }

    if (!m_transitions.isEmpty()) {
        CSSPropertyTransitionsMap::const_iterator transitionsEnd = m_transitions.end();
        for (CSSPropertyTransitionsMap::const_iterator it = m_transitions.begin(); it != transitionsEnd; ++it) {
            ImplicitAnimation* anim = it->value.get();
            if (anim->running())
                ++count;
        }
    }
    
    return count;
}

} // namespace WebCore
