Source/core/svg/properties/NewSVGAnimatedProperty.h

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#ifndef NewSVGAnimatedProperty_h
#define NewSVGAnimatedProperty_h

#include "bindings/v8/ExceptionStatePlaceholder.h"
#include "bindings/v8/ScriptWrappable.h"
#include "core/dom/ExceptionCode.h"
#include "core/svg/SVGParsingError.h"
#include "core/svg/properties/NewSVGPropertyTearOff.h"
#include "core/svg/properties/SVGPropertyInfo.h"
#include "wtf/Noncopyable.h"
#include "wtf/PassRefPtr.h"
#include "wtf/RefCounted.h"

namespace WebCore {

class SVGElement;

class NewSVGAnimatedPropertyBase : public RefCounted<NewSVGAnimatedPropertyBase> {
public:
    virtual ~NewSVGAnimatedPropertyBase();

    virtual NewSVGPropertyBase* currentValueBase() = 0;

    virtual void animationStarted();
    virtual PassRefPtr<NewSVGPropertyBase> createAnimatedValue() = 0;
    virtual void setAnimatedValue(PassRefPtr<NewSVGPropertyBase>) = 0;
    virtual void animationEnded();

    virtual bool needsSynchronizeAttribute() = 0;
    virtual void synchronizeAttribute();

    AnimatedPropertyType type() const
    {
        return m_type;
    }

    SVGElement* contextElement() const
    {
        return m_contextElement;
    }

    const QualifiedName& attributeName() const
    {
        return m_attributeName;
    }

    bool isAnimating() const
    {
        return m_isAnimating;
    }

    bool isReadOnly() const
    {
        return m_isReadOnly;
    }

    void setReadOnly()
    {
        m_isReadOnly = true;
    }

    bool isSpecified() const;

protected:
    NewSVGAnimatedPropertyBase(AnimatedPropertyType, SVGElement*, const QualifiedName& attributeName);
    void commitChange();

private:
    const AnimatedPropertyType m_type;
    bool m_isReadOnly;
    bool m_isAnimating;

    // This reference is kept alive from V8 wrapper
    SVGElement* m_contextElement;

    const QualifiedName& m_attributeName;

    WTF_MAKE_NONCOPYABLE(NewSVGAnimatedPropertyBase);
};

template <typename Property>
class NewSVGAnimatedPropertyCommon : public NewSVGAnimatedPropertyBase {
public:
    Property* baseValue()
    {
        return m_baseValue.get();
    }

    Property* currentValue()
    {
        return m_currentValue ? m_currentValue.get() : m_baseValue.get();
    }

    const Property* currentValue() const
    {
        return const_cast<NewSVGAnimatedPropertyCommon*>(this)->currentValue();
    }

    virtual NewSVGPropertyBase* currentValueBase() OVERRIDE
    {
        return currentValue();
    }

    void setBaseValueAsString(const String& value, SVGParsingError& parseError)
    {
        TrackExceptionState es;

        m_baseValue->setValueAsString(value, es);

        if (es.hadException())
            parseError = ParsingAttributeFailedError;
    }

    virtual PassRefPtr<NewSVGPropertyBase> createAnimatedValue() OVERRIDE
    {
        return m_baseValue->clone();
    }

    virtual void setAnimatedValue(PassRefPtr<NewSVGPropertyBase> passValue) OVERRIDE
    {
        ASSERT(isAnimating());

        RefPtr<NewSVGPropertyBase> value = passValue;
        ASSERT(value->type() == Property::classType());
        m_currentValue = static_pointer_cast<Property>(value.release());
    }

    virtual void animationEnded() OVERRIDE
    {
        NewSVGAnimatedPropertyBase::animationEnded();

        ASSERT(m_currentValue);
        m_currentValue.clear();
    }

protected:
    NewSVGAnimatedPropertyCommon(SVGElement* contextElement, const QualifiedName& attributeName, PassRefPtr<Property> initialValue)
        : NewSVGAnimatedPropertyBase(Property::classType(), contextElement, attributeName)
        , m_baseValue(initialValue)
    {
    }

private:
    RefPtr<Property> m_baseValue;
    RefPtr<Property> m_currentValue;
};

// Implementation of SVGAnimatedProperty which uses primitive types.
// This is for classes which return primitive type for its "animVal".
// Examples are SVGAnimatedBoolean, SVGAnimatedNumber, etc.
template <typename Property, typename TearOffType = typename Property::TearOffType, typename PrimitiveType = typename Property::PrimitiveType>
class NewSVGAnimatedProperty : public NewSVGAnimatedPropertyCommon<Property> {
public:
    static PassRefPtr<NewSVGAnimatedProperty<Property> > create(SVGElement* contextElement, const QualifiedName& attributeName, PassRefPtr<Property> initialValue)
    {
        return adoptRef(new NewSVGAnimatedProperty<Property>(contextElement, attributeName, initialValue));
    }

    virtual bool needsSynchronizeAttribute() OVERRIDE
    {
        // DOM attribute synchronization is only needed if tear-off is being touched from javascript or the property is being animated.
        // This prevents unnecessary attribute creation on target element.
        return m_baseValueUpdated || this->isAnimating();
    }

    virtual void synchronizeAttribute() OVERRIDE
    {
        NewSVGAnimatedPropertyBase::synchronizeAttribute();
        m_baseValueUpdated = false;
    }

    // SVGAnimated* DOM Spec implementations:

    // baseVal()/setBaseVal()/animVal() are only to be used from SVG DOM implementation.
    // Use currentValue() from C++ code.
    PrimitiveType baseVal()
    {
        return this->baseValue()->value();
    }

    void setBaseVal(PrimitiveType value, WebCore::ExceptionState& exceptionState)
    {
        if (this->isReadOnly()) {
            exceptionState.throwDOMException(NoModificationAllowedError, "The attribute is read-only.");
            return;
        }

        this->baseValue()->setValue(value);
        m_baseValueUpdated = true;

        ASSERT(this->attributeName() != nullQName());
        this->contextElement()->invalidateSVGAttributes();
        this->contextElement()->svgAttributeChanged(this->attributeName());
    }

    PrimitiveType animVal()
    {
        return this->currentValue()->value();
    }

protected:
    NewSVGAnimatedProperty(SVGElement* contextElement, const QualifiedName& attributeName, PassRefPtr<Property> initialValue)
        : NewSVGAnimatedPropertyCommon<Property>(contextElement, attributeName, initialValue)
        , m_baseValueUpdated(false)
    {
    }

    bool m_baseValueUpdated;
};

// Implementation of SVGAnimatedProperty which uses tear-off value types.
// These classes has "void" for its PrimitiveType.
// This is for classes which return special type for its "animVal".
// Examples are SVGAnimatedLength, SVGAnimatedRect, SVGAnimated*List, etc.
template <typename Property, typename TearOffType>
class NewSVGAnimatedProperty<Property, TearOffType, void> : public NewSVGAnimatedPropertyCommon<Property> {
public:
    static PassRefPtr<NewSVGAnimatedProperty<Property> > create(SVGElement* contextElement, const QualifiedName& attributeName, PassRefPtr<Property> initialValue)
    {
        return adoptRef(new NewSVGAnimatedProperty<Property>(contextElement, attributeName, initialValue));
    }

    virtual void setAnimatedValue(PassRefPtr<NewSVGPropertyBase> value) OVERRIDE
    {
        NewSVGAnimatedPropertyCommon<Property>::setAnimatedValue(value);
        updateAnimValTearOffIfNeeded();
    }

    virtual void animationEnded() OVERRIDE
    {
        NewSVGAnimatedPropertyCommon<Property>::animationEnded();
        updateAnimValTearOffIfNeeded();
    }

    virtual bool needsSynchronizeAttribute() OVERRIDE
    {
        // DOM attribute synchronization is only needed if tear-off is being touched from javascript or the property is being animated.
        // This prevents unnecessary attribute creation on target element.
        return m_baseValTearOff || this->isAnimating();
    }

    // SVGAnimated* DOM Spec implementations:

    // baseVal()/animVal() are only to be used from SVG DOM implementation.
    // Use currentValue() from C++ code.
    virtual TearOffType* baseVal()
    {
        if (!m_baseValTearOff) {
            m_baseValTearOff = TearOffType::create(this->baseValue(), this->contextElement(), PropertyIsNotAnimVal, this->attributeName());
            if (this->isReadOnly())
                m_baseValTearOff->setIsReadOnlyProperty();
        }

        return m_baseValTearOff.get();
    }

    TearOffType* animVal()
    {
        if (!m_animValTearOff)
            m_animValTearOff = TearOffType::create(this->currentValue(), this->contextElement(), PropertyIsAnimVal, this->attributeName());

        return m_animValTearOff.get();
    }

protected:
    NewSVGAnimatedProperty(SVGElement* contextElement, const QualifiedName& attributeName, PassRefPtr<Property> initialValue)
        : NewSVGAnimatedPropertyCommon<Property>(contextElement, attributeName, initialValue)
    {
    }

private:
    void updateAnimValTearOffIfNeeded()
    {
        if (m_animValTearOff)
            m_animValTearOff->setTarget(this->currentValue());
    }

    // When still (not animated):
    //     Both m_animValTearOff and m_baseValTearOff target m_baseValue.
    // When animated:
    //     m_animValTearOff targets m_currentValue.
    //     m_baseValTearOff targets m_baseValue.
    RefPtr<TearOffType> m_baseValTearOff;
    RefPtr<TearOffType> m_animValTearOff;
};

}

#endif // NewSVGAnimatedProperty_h