qmap.h

/****************************************************************************
** $Id: //depot/qt/main/src/tools/qmap.h#26 $
**
** Definition of QMap class
**
** Created : 990406
**
** Copyright (C) 1992-2000 Trolltech AS.  All rights reserved.
**
** This file is part of the tools module of the Qt GUI Toolkit.
**
** This file may be distributed under the terms of the Q Public License
** as defined by Trolltech AS of Norway and appearing in the file
** LICENSE.QPL included in the packaging of this file.
**
** This file may be distributed and/or modified under the terms of the
** GNU General Public License version 2 as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL included in the
** packaging of this file.
**
** Licensees holding valid Qt Enterprise Edition or Qt Professional Edition
** licenses may use this file in accordance with the Qt Commercial License
** Agreement provided with the Software.
**
** This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
** WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
**
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**   information about Qt Commercial License Agreements.
** See http://www.trolltech.com/qpl/ for QPL licensing information.
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**********************************************************************/

#ifndef QMAP_H
#define QMAP_H

#ifndef QT_H
#include "qshared.h"
#include "qdatastream.h"
#endif // QT_H


struct QMapNodeBase
{
    enum Color { Red, Black };

    QMapNodeBase* left;
    QMapNodeBase* right;
    QMapNodeBase* parent;

    Color color;

    QMapNodeBase* minimum() {
        QMapNodeBase* x = this;
        while ( x->left )
            x = x->left;
        return x;
    }

    QMapNodeBase* maximum() {
        QMapNodeBase* x = this;
        while ( x->right )
            x = x->right;
        return x;
    }
};


template <class K, class T>
struct QMapNode : public QMapNodeBase
{
    QMapNode( const K& _key, const T& _data ) { data = _data; key = _key; }
    QMapNode( const K& _key )      { key = _key; }
    QMapNode( const QMapNode<K,T>& _n ) { key = _n.key; data = _n.data; }
    QMapNode() { }
    T data;
    K key;
};


template<class K, class T>
class Q_EXPORT QMapIterator
{
 public:
    /**
     * Typedefs
     */
    typedef QMapNode< K, T >* NodePtr;

    /**
     * Variables
     */
    QMapNode<K,T>* node;

    /**
     * Functions
     */
    QMapIterator() : node( 0 ) {}
    QMapIterator( QMapNode<K,T>* p ) : node( p ) {}
    QMapIterator( const QMapIterator<K,T>& it ) : node( it.node ) {}

    bool operator==( const QMapIterator<K,T>& it ) const { return node == it.node; }
    bool operator!=( const QMapIterator<K,T>& it ) const { return node != it.node; }
    T& operator*() { return node->data; }
    const T& operator*() const { return node->data; }

    // Cannot have this - some compilers are too stupid
    //T* operator->() const { return &(node->data); }

    const K& key() const { return node->key; }
    T& data() { return node->data; }
    const T& data() const { return node->data; }

private:
    int inc() {
        QMapNodeBase* tmp = node;
        if ( tmp->right ) {
            tmp = tmp->right;
            while ( tmp->left )
                tmp = tmp->left;
        } else {
            QMapNodeBase* y = tmp->parent;
            while (tmp == y->right) {
                tmp = y;
                y = y->parent;
            }
            if (tmp->right != y)
                tmp = y;
        }
        node = (NodePtr)tmp;
        return 0;
    }

    int dec() {
        QMapNodeBase* tmp = node;
        if (tmp->color == QMapNodeBase::Red &&
            tmp->parent->parent == tmp ) {
            tmp = tmp->right;
        } else if (tmp->left != 0) {
            QMapNodeBase* y = tmp->left;
            while ( y->right )
                y = y->right;
            tmp = y;
        } else {
            QMapNodeBase* y = tmp->parent;
            while (tmp == y->left) {
                tmp = y;
                y = y->parent;
            }
            tmp = y;
        }
        node = (NodePtr)tmp;
        return 0;
    }

public:
    QMapIterator<K,T>& operator++() {
        inc();
        return *this;
    }

    QMapIterator<K,T> operator++(int) {
        QMapIterator<K,T> tmp = *this;
        inc();
        return tmp;
    }

    QMapIterator<K,T>& operator--() {
        dec();
        return *this;
    }

    QMapIterator<K,T> operator--(int) {
        QMapIterator<K,T> tmp = *this;
        dec();
        return tmp;
    }
};

template<class K, class T>
class Q_EXPORT QMapConstIterator
{
 public:
    /**
     * Typedefs
     */
    typedef QMapNode< K, T >* NodePtr;

    /**
     * Variables
     */
    QMapNode<K,T>* node;

    /**
     * Functions
     */
    QMapConstIterator() : node( 0 ) {}
    QMapConstIterator( QMapNode<K,T>* p ) : node( p ) {}
    QMapConstIterator( const QMapConstIterator<K,T>& it ) : node( it.node ) {}
    QMapConstIterator( const QMapIterator<K,T>& it ) : node( it.node ) {}

    bool operator==( const QMapConstIterator<K,T>& it ) const { return node == it.node; }
    bool operator!=( const QMapConstIterator<K,T>& it ) const { return node != it.node; }
    const T& operator*()  const { return node->data; }

    // Cannot have this - some compilers are too stupid
    //const T* operator->() const { return &(node->data); }

    const K& key() const { return node->key; }
    const T& data() const { return node->data; }

private:
    int inc() {
        QMapNodeBase* tmp = node;
        if ( tmp->right ) {
            tmp = tmp->right;
            while ( tmp->left )
                tmp = tmp->left;
        } else {
            QMapNodeBase* y = tmp->parent;
            while (tmp == y->right) {
                tmp = y;
                y = y->parent;
            }
            if (tmp->right != y)
                tmp = y;
        }
        node = (NodePtr)tmp;
        return 0;
    }

    int dec() {
        QMapNodeBase* tmp = node;
        if (tmp->color == QMapNodeBase::Red &&
            tmp->parent->parent == tmp ) {
            tmp = tmp->right;
        } else if (tmp->left != 0) {
            QMapNodeBase* y = tmp->left;
            while ( y->right )
                y = y->right;
            tmp = y;
        } else {
            QMapNodeBase* y = tmp->parent;
            while (tmp == y->left) {
                tmp = y;
                y = y->parent;
            }
            tmp = y;
        }
        node = (NodePtr)tmp;
        return 0;
    }

public:
    QMapConstIterator<K,T>& operator++() {
        inc();
        return *this;
    }

    QMapConstIterator<K,T> operator++(int) {
        QMapConstIterator<K,T> tmp = *this;
        inc();
        return tmp;
    }

    QMapConstIterator<K,T>& operator--() {
        dec();
        return *this;
    }

    QMapConstIterator<K,T> operator--(int) {
        QMapConstIterator<K,T> tmp = *this;
        dec();
        return tmp;
    }
};


class Q_EXPORT QMapPrivateBase : public QShared
{
public:
    QMapPrivateBase() {
        node_count = 0;
    }
    QMapPrivateBase( const QMapPrivateBase* _map) {
        node_count = _map->node_count;
    }

    /**
     * Implementations of basic tree algorithms
     */
    void rotateLeft( QMapNodeBase* x, QMapNodeBase*& root);
    void rotateRight( QMapNodeBase* x, QMapNodeBase*& root );
    void rebalance( QMapNodeBase* x, QMapNodeBase*& root );
    QMapNodeBase* removeAndRebalance( QMapNodeBase* z, QMapNodeBase*& root,
                                      QMapNodeBase*& leftmost,
                                      QMapNodeBase*& rightmost );

    /**
     * Variables
     */
    int node_count;
};


template <class Key, class T>
class QMapPrivate : public QMapPrivateBase
{
public:
    /**
     * Typedefs
     */
    typedef QMapIterator< Key, T > Iterator;
    typedef QMapConstIterator< Key, T > ConstIterator;
    typedef QMapNode< Key, T > Node;
    typedef QMapNode< Key, T >* NodePtr;

    /**
     * Functions
     */
    QMapPrivate() {
        header = new Node;
        header->color = QMapNodeBase::Red; // Mark the header
        header->parent = 0;
        header->left = header->right = header;
    }
    QMapPrivate( const QMapPrivate< Key, T >* _map ) : QMapPrivateBase( _map ) {
        header = new Node;
        header->color = QMapNodeBase::Red; // Mark the header
        if ( _map->header->parent == 0 ) {
            header->parent = 0;
            header->left = header->right = header;
        } else {
            header->parent = copy( (NodePtr)(_map->header->parent) );
            header->parent->parent = header;
            header->left = header->parent->minimum();
            header->right = header->parent->maximum();
        }
    }
    ~QMapPrivate() { clear(); delete header; }

    NodePtr copy( NodePtr p ) {
        if ( !p )
            return 0;
        NodePtr n = new Node( *p );
        n->color = p->color;
        if ( p->left ) {
            n->left = copy( (NodePtr)(p->left) );
            n->left->parent = n;
        } else {
            n->left = 0;
        }
        if ( p->right ) {
            n->right = copy( (NodePtr)(p->right) );
            n->right->parent = n;
        } else {
            n->right = 0;
        }
        return n;
    }

    void clear() {
        clear( (NodePtr)(header->parent) );
        header->color = QMapNodeBase::Red;
        header->parent = 0;
        header->left = header->right = header;
        node_count = 0;
    }

    void clear( NodePtr p ) {
        while ( p != 0 ) {
            clear( (NodePtr)p->right );
            NodePtr y = (NodePtr)p->left;
            delete p;
            p = y;
        }
    }

    Iterator begin()    { return Iterator( (NodePtr)(header->left ) ); }
    Iterator end()      { return Iterator( header ); }
    ConstIterator begin() const { return ConstIterator( (NodePtr)(header->left ) ); }
    ConstIterator end() const { return ConstIterator( header ); }

    ConstIterator find(const Key& k) const {
        QMapNodeBase* y = header;        // Last node
        QMapNodeBase* x = header->parent; // Root node.

        while ( x != 0 ) {
            // If as k <= key(x) go left
            if ( !( key(x) < k ) ) {
                y = x;
                x = x->left;
            } else {
                x = x->right;
            }
        }

        // Was k bigger/smaller then the biggest/smallest
        // element of the tree ? Return end()
        if ( y == header || k < key(y) )
            return ConstIterator( header );
        return ConstIterator( (NodePtr)y );
    }

    void remove( Iterator it ) {
        NodePtr del = (NodePtr) removeAndRebalance( it.node, header->parent, header->left, header->right );
        delete del;
        --node_count;
    }

#ifdef QT_QMAP_DEBUG
    void inorder( QMapNodeBase* x = 0, int level = 0 ){
        if ( !x )
            x = header->parent;
        if ( x->left )
            inorder( x->left, level + 1 );
    //cout << level << " Key=" << key(x) << " Value=" << ((NodePtr)x)->data << endl;
        if ( x->right )
            inorder( x->right, level + 1 );
    }
#endif

    Iterator insertMulti(const Key& v){
        QMapNodeBase* y = header;
        QMapNodeBase* x = header->parent;
        while (x != 0){
            y = x;
            x = ( v < key(x) ) ? x->left : x->right;
        }
        return insert(x, y, v);
    }

    Iterator insertSingle( const Key& k ) {
        // Search correct position in the tree
        QMapNodeBase* y = header;
        QMapNodeBase* x = header->parent;
        bool result = TRUE;
        while ( x != 0 ) {
            result = ( k < key(x) );
            y = x;
            x = result ? x->left : x->right;
        }
        // Get iterator on the last not empty one
        Iterator j( (NodePtr)y );
        if ( result ) {
            // Smaller then the leftmost one ?
            if ( j == begin() ) {
                return insert(x, y, k );
            } else {
                // Perhaps daddy is the right one ?
                --j;
            }
        }
        // Really bigger ?
        if ( (j.node->key) < k )
            return insert(x, y, k );
        // We are going to replace a node
        return j;
    }

    Iterator insert( QMapNodeBase* x, QMapNodeBase* y, const Key& k ) {
        NodePtr z = new Node( k );
        if (y == header || x != 0 || k < key(y) ) {
            y->left = z;                // also makes leftmost = z when y == header
            if ( y == header ) {
                header->parent = z;
                header->right = z;
            } else if ( y == header->left )
                header->left = z;           // maintain leftmost pointing to min node
        } else {
            y->right = z;
            if ( y == header->right )
                header->right = z;          // maintain rightmost pointing to max node
        }
        z->parent = y;
        z->left = 0;
        z->right = 0;
        rebalance( z, header->parent );
        ++node_count;
        return Iterator(z);
    }

protected:
    /**
     * Helpers
     */
    const Key& key( QMapNodeBase* b ) const { return ((NodePtr)b)->key; }

    /**
     * Variables
     */
    NodePtr header;
};


template<class Key, class T>
class Q_EXPORT QMap
{
public:
    /**
     * Typedefs
     */
    typedef QMapIterator< Key, T > Iterator;
    typedef QMapConstIterator< Key, T > ConstIterator;
    typedef T ValueType;
    typedef QMapPrivate< Key, T > Priv;

    /**
     * API
     */
    QMap() { sh = new QMapPrivate< Key, T >; }
    QMap( const QMap<Key,T>& m ) { sh = m.sh; sh->ref(); }
    ~QMap() { if ( sh->deref() ) delete sh; }

    QMap<Key,T>& operator= ( const QMap<Key,T>& m )
      { m.sh->ref(); if ( sh->deref() ) delete sh; sh = m.sh; return *this; }

    Iterator begin() { detach(); return sh->begin(); }
    Iterator end() { detach(); return sh->end(); }
    ConstIterator begin() const { return ((const Priv*)sh)->begin(); }
    ConstIterator end() const { return ((const Priv*)sh)->end(); }

    Iterator find ( const Key& k )
        { detach(); return Iterator( sh->find( k ).node ); }
    ConstIterator find ( const Key& k ) const
        { return sh->find( k ); }
    T& operator[] ( const Key& k ) {
        detach(); QMapNode<Key,T>* p = sh->find( k ).node;
        if ( p != sh->end().node ) return p->data;
        return insert( k, T() ).data(); }
    const T& operator[] ( const Key& k ) const
        { return sh->find( k ).data(); }
    bool contains ( const Key& k ) const
        { return find( k ) != end(); }
        //{ return sh->find( k ) != ((const Priv*)sh)->end(); }

    uint count() const { return sh->node_count; }

    bool isEmpty() const { return sh->node_count == 0; }

    Iterator insert( const Key& key, const T& value ) {
        detach();
        Iterator it = sh->insertSingle( key );
        it.data() = value;
        return it;
    }

    void remove( Iterator it ) { detach(); sh->remove( it ); }
    void remove( const Key& k ) {
        detach();
        Iterator it( sh->find( k ).node );
        if ( it != end() )
            sh->remove( it );
    }

    Iterator replace( const Key& k, const T& v ) {
        remove( k );
        return insert( k, v );
    }

    void clear() { if ( sh->count == 1 ) sh->clear(); else { sh->deref(); sh = new QMapPrivate<Key,T>; } }

#if defined(Q_FULL_TEMPLATE_INSTANTIATION)
    bool operator==( const QMap<Key,T>& ) const { return FALSE; }
#endif

protected:
    /**
     * Helpers
     */
    void detach() { if ( sh->count > 1 ) { sh->deref(); sh = new QMapPrivate<Key,T>( sh ); } }

    Priv* sh;
};


#ifndef QT_NO_DATASTREAM
template<class Key, class T>
inline QDataStream& operator>>( QDataStream& s, QMap<Key,T>& m ) {
    m.clear();
    Q_UINT32 c;
    s >> c;
    for( Q_UINT32 i = 0; i < c; ++i ) {
        Key k; T t;
        s >> k >> t;
        m.insert( k, t );
        if ( s.atEnd() )
            break;
    }
    return s;
}


template<class Key, class T>
inline QDataStream& operator<<( QDataStream& s, const QMap<Key,T>& m ) {
    s << (Q_UINT32)m.count();
    QMapConstIterator<Key,T> it = m.begin();
    for( ; it != m.end(); ++it )
        s << it.key() << it.data();
    return s;
}
#endif

#endif // QMAP_H