WebCore/svg/SVGAnimatedTemplate.h

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

#ifndef SVGAnimatedTemplate_h
#define SVGAnimatedTemplate_h

#if ENABLE(SVG)
#include <wtf/RefCounted.h>
#include "AtomicString.h"
#include "Attribute.h"

namespace WebCore {

    class FloatRect;
    class SVGAngle;
    class SVGElement;
    class SVGLength;
    class SVGLengthList;
    class SVGNumberList;
    class SVGPreserveAspectRatio;
    class SVGTransformList;
    class String;
    class QualifiedName;

    struct SVGAnimatedTypeWrapperKey {            
        // Empty value
        SVGAnimatedTypeWrapperKey()
            : element(0)
            , attributeName(0)
        { }
        
        // Deleted value
        explicit SVGAnimatedTypeWrapperKey(bool)
            : element(reinterpret_cast<SVGElement*>(-1))
            , attributeName(0)
        { }
        
        SVGAnimatedTypeWrapperKey(const SVGElement* _element, const AtomicString& _attributeName)
            : element(_element)
            , attributeName(_attributeName.impl())
        {
            ASSERT(element);
            ASSERT(attributeName);
        }
        
        bool operator==(const SVGAnimatedTypeWrapperKey& other) const
        {
            return element == other.element && attributeName == other.attributeName;
        }
        
        const SVGElement* element;
        AtomicStringImpl* attributeName;
    };
    
    struct SVGAnimatedTypeWrapperKeyHash {
        static unsigned hash(const SVGAnimatedTypeWrapperKey& key)
        {
            return StringImpl::computeHash((::UChar*) &key, sizeof(SVGAnimatedTypeWrapperKey) / sizeof(::UChar));
        }
            
        static bool equal(const SVGAnimatedTypeWrapperKey& a, const SVGAnimatedTypeWrapperKey& b)
        {
            return a == b;
        }

        static const bool safeToCompareToEmptyOrDeleted = true;
    };
    
    struct SVGAnimatedTypeWrapperKeyHashTraits : WTF::GenericHashTraits<SVGAnimatedTypeWrapperKey> {
        static const bool emptyValueIsZero = true;
        static const bool needsDestruction = false;
        
        static const SVGAnimatedTypeWrapperKey& deletedValue()
        {
            static SVGAnimatedTypeWrapperKey deletedKey(true);
            return deletedKey;
        }
        
        static const SVGAnimatedTypeWrapperKey& emptyValue()
        {
            static SVGAnimatedTypeWrapperKey emptyKey;
            return emptyKey;
        }
    };
    
    template<typename BareType>
    class SVGAnimatedTemplate : public RefCounted<SVGAnimatedTemplate<BareType> >
    {
    public:
        SVGAnimatedTemplate(const QualifiedName& attributeName)
            : m_associatedAttributeName(attributeName)
        {
        }

        virtual ~SVGAnimatedTemplate() { forgetWrapper(this); }

        virtual BareType baseVal() const = 0;
        virtual void setBaseVal(BareType newBaseVal) = 0;

        virtual BareType animVal() const = 0;
        virtual void setAnimVal(BareType newAnimVal) = 0;

        typedef HashMap<SVGAnimatedTypeWrapperKey, SVGAnimatedTemplate<BareType>*, SVGAnimatedTypeWrapperKeyHash, SVGAnimatedTypeWrapperKeyHashTraits > ElementToWrapperMap;
        typedef typename ElementToWrapperMap::const_iterator ElementToWrapperMapIterator;

        static ElementToWrapperMap* wrapperCache()
        {
            static ElementToWrapperMap* s_wrapperCache = new ElementToWrapperMap;                
            return s_wrapperCache;
        }
        
        static void forgetWrapper(SVGAnimatedTemplate<BareType>* wrapper)
        {
            ElementToWrapperMap* cache = wrapperCache();
            ElementToWrapperMapIterator itr = cache->begin();
            ElementToWrapperMapIterator end = cache->end();
            for (; itr != end; ++itr) {
                if (itr->second == wrapper) {
                    cache->remove(itr->first);
                    break;
                }
            }
        }

       const QualifiedName& associatedAttributeName() const { return m_associatedAttributeName; }

    private:
       const QualifiedName& m_associatedAttributeName;
    };

    template <class Type, class SVGElementSubClass>
    Type* lookupOrCreateWrapper(const SVGElementSubClass* element, const QualifiedName& domAttrName, const AtomicString& attrIdentifier) {
        SVGAnimatedTypeWrapperKey key(element, attrIdentifier);
        Type* wrapper = static_cast<Type*>(Type::wrapperCache()->get(key));
        if (!wrapper) {
            wrapper = new Type(element, domAttrName);
            Type::wrapperCache()->set(key, wrapper);
        }
        return wrapper;
    }

    // Common type definitions, to ease IDL generation...
    typedef SVGAnimatedTemplate<SVGAngle*> SVGAnimatedAngle;
    typedef SVGAnimatedTemplate<bool> SVGAnimatedBoolean;
    typedef SVGAnimatedTemplate<int> SVGAnimatedEnumeration;
    typedef SVGAnimatedTemplate<long> SVGAnimatedInteger;
    typedef SVGAnimatedTemplate<SVGLength> SVGAnimatedLength;
    typedef SVGAnimatedTemplate<SVGLengthList*> SVGAnimatedLengthList;
    typedef SVGAnimatedTemplate<float> SVGAnimatedNumber;
    typedef SVGAnimatedTemplate<SVGNumberList*> SVGAnimatedNumberList; 
    typedef SVGAnimatedTemplate<SVGPreserveAspectRatio*> SVGAnimatedPreserveAspectRatio;
    typedef SVGAnimatedTemplate<FloatRect> SVGAnimatedRect;
    typedef SVGAnimatedTemplate<String> SVGAnimatedString;
    typedef SVGAnimatedTemplate<SVGTransformList*> SVGAnimatedTransformList;
}

#endif // ENABLE(SVG)
#endif // SVGAnimatedTemplate_h