/*

 * Copyright (C) 2005, 2006, 2007, 2008 Apple Inc. 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.

 *

 */

#ifndef WTF_HashSet_h

#define WTF_HashSet_h

#include "FastAllocBase.h"

#include "HashTable.h"

namespace WTF {

    template<typename Value, typename HashFunctions, typename Traits> class HashSet;

    template<typename Value, typename HashFunctions, typename Traits>

    void deleteAllValues(const HashSet<Value, HashFunctions, Traits>&);

    template<typename Value, typename HashFunctions, typename Traits>

    void fastDeleteAllValues(const HashSet<Value, HashFunctions, Traits>&);

    template<typename T> struct IdentityExtractor;

    template<typename ValueArg, typename HashArg = typename DefaultHash<ValueArg>::Hash,

        typename TraitsArg = HashTraits<ValueArg> > class HashSet : public FastAllocBase {

    private:

        typedef HashArg HashFunctions;

        typedef TraitsArg ValueTraits;

    public:

        typedef typename ValueTraits::TraitType ValueType;

    private:

        typedef HashTable<ValueType, ValueType, IdentityExtractor<ValueType>,

            HashFunctions, ValueTraits, ValueTraits> HashTableType;

    public:

        typedef HashTableConstIteratorAdapter<HashTableType, ValueType> iterator;

        typedef HashTableConstIteratorAdapter<HashTableType, ValueType> const_iterator;

        void swap(HashSet&);

        int size() const;

        int capacity() const;

        bool isEmpty() const;

        iterator begin() const;

        iterator end() const;

        iterator find(const ValueType&) const;

        bool contains(const ValueType&) const;

        // An alternate version of find() that finds the object by hashing and comparing

        // with some other type, to avoid the cost of type conversion. HashTranslator

        // must have the following function members:

        //   static unsigned hash(const T&);

        //   static bool equal(const ValueType&, const T&);

        template<typename T, typename HashTranslator> iterator find(const T&) const;

        template<typename T, typename HashTranslator> bool contains(const T&) const;

        // The return value is a pair of an interator to the new value's location, 

        // and a bool that is true if an new entry was added.

        pair<iterator, bool> add(const ValueType&);

        // An alternate version of add() that finds the object by hashing and comparing

        // with some other type, to avoid the cost of type conversion if the object is already

        // in the table. HashTranslator must have the following function members:

        //   static unsigned hash(const T&);

        //   static bool equal(const ValueType&, const T&);

        //   static translate(ValueType&, const T&, unsigned hashCode);

        template<typename T, typename HashTranslator> pair<iterator, bool> add(const T&);

        void remove(const ValueType&);

        void remove(iterator);

        void clear();

    private:

        friend void deleteAllValues<>(const HashSet&);

        friend void fastDeleteAllValues<>(const HashSet&);

        HashTableType m_impl;

    };

    template<typename T> struct IdentityExtractor {

        static const T& extract(const T& t) { return t; }

    };

    template<typename ValueType, typename ValueTraits, typename T, typename Translator>

    struct HashSetTranslatorAdapter {

        static unsigned hash(const T& key) { return Translator::hash(key); }

        static bool equal(const ValueType& a, const T& b) { return Translator::equal(a, b); }

        static void translate(ValueType& location, const T& key, const T&, unsigned hashCode)

        {

            Translator::translate(location, key, hashCode);

        }

    };

    template<typename T, typename U, typename V>

    inline void HashSet<T, U, V>::swap(HashSet& other)

    {

        m_impl.swap(other.m_impl); 

    }

    template<typename T, typename U, typename V>

    inline int HashSet<T, U, V>::size() const

    {

        return m_impl.size(); 

    }

    template<typename T, typename U, typename V>

    inline int HashSet<T, U, V>::capacity() const

    {

        return m_impl.capacity(); 

    }

    template<typename T, typename U, typename V>

    inline bool HashSet<T, U, V>::isEmpty() const

    {

        return m_impl.isEmpty(); 

    }

    template<typename T, typename U, typename V>

    inline typename HashSet<T, U, V>::iterator HashSet<T, U, V>::begin() const

    {

        return m_impl.begin(); 

    }

    template<typename T, typename U, typename V>

    inline typename HashSet<T, U, V>::iterator HashSet<T, U, V>::end() const

    {

        return m_impl.end(); 

    }

    template<typename T, typename U, typename V>

    inline typename HashSet<T, U, V>::iterator HashSet<T, U, V>::find(const ValueType& value) const

    {

        return m_impl.find(value); 

    }

    template<typename T, typename U, typename V>

    inline bool HashSet<T, U, V>::contains(const ValueType& value) const

    {

        return m_impl.contains(value); 

    }

    template<typename Value, typename HashFunctions, typename Traits>

    template<typename T, typename HashTranslator>

    typename HashSet<Value, HashFunctions, Traits>::iterator

    inline HashSet<Value, HashFunctions, Traits>::find(const T& value) const

    {

        typedef HashSetTranslatorAdapter<ValueType, ValueTraits, T, HashTranslator> Adapter;

        return m_impl.template find<T, Adapter>(value);

    }

    template<typename Value, typename HashFunctions, typename Traits>

    template<typename T, typename HashTranslator>

    inline bool HashSet<Value, HashFunctions, Traits>::contains(const T& value) const

    {

        typedef HashSetTranslatorAdapter<ValueType, ValueTraits, T, HashTranslator> Adapter;

        return m_impl.template contains<T, Adapter>(value);

    }

    template<typename T, typename U, typename V>

    pair<typename HashSet<T, U, V>::iterator, bool> HashSet<T, U, V>::add(const ValueType& value)

    {

        return m_impl.add(value);

    }

    template<typename Value, typename HashFunctions, typename Traits>

    template<typename T, typename HashTranslator>

    pair<typename HashSet<Value, HashFunctions, Traits>::iterator, bool>

    HashSet<Value, HashFunctions, Traits>::add(const T& value)

    {

        typedef HashSetTranslatorAdapter<ValueType, ValueTraits, T, HashTranslator> Adapter;

        return m_impl.template addPassingHashCode<T, T, Adapter>(value, value);

    }

    template<typename T, typename U, typename V>

    inline void HashSet<T, U, V>::remove(iterator it)

    {

        if (it.m_impl == m_impl.end())

            return;

        m_impl.internalCheckTableConsistency();

        m_impl.removeWithoutEntryConsistencyCheck(it.m_impl);

    }

    template<typename T, typename U, typename V>

    inline void HashSet<T, U, V>::remove(const ValueType& value)

    {

        remove(find(value));

    }

    template<typename T, typename U, typename V>

    inline void HashSet<T, U, V>::clear()

    {

        m_impl.clear(); 

    }

    template<typename ValueType, typename HashTableType>

    void deleteAllValues(HashTableType& collection)

    {

        typedef typename HashTableType::const_iterator iterator;

        iterator end = collection.end();

        for (iterator it = collection.begin(); it != end; ++it)

            delete *it;

    }

    template<typename T, typename U, typename V>

    inline void deleteAllValues(const HashSet<T, U, V>& collection)

    {

        deleteAllValues<typename HashSet<T, U, V>::ValueType>(collection.m_impl);

    }

    template<typename ValueType, typename HashTableType>

    void fastDeleteAllValues(HashTableType& collection)

    {

        typedef typename HashTableType::const_iterator iterator;

        iterator end = collection.end();

        for (iterator it = collection.begin(); it != end; ++it)

            fastDelete(*it);

    }

    template<typename T, typename U, typename V>

    inline void fastDeleteAllValues(const HashSet<T, U, V>& collection)

    {

        fastDeleteAllValues<typename HashSet<T, U, V>::ValueType>(collection.m_impl);

    }

    template<typename T, typename U, typename V, typename W>

    inline void copyToVector(const HashSet<T, U, V>& collection, W& vector)

    {

        typedef typename HashSet<T, U, V>::const_iterator iterator;

        vector.resize(collection.size());

        iterator it = collection.begin();

        iterator end = collection.end();

        for (unsigned i = 0; it != end; ++it, ++i)

            vector[i] = *it;

    }  

} // namespace WTF

using WTF::HashSet;

#endif /* WTF_HashSet_h */