// -*- mode: c++; c-basic-offset: 4 -*-
/*
 * This file is part of the DOM implementation for KDE.
 * Copyright (C) 2005 Apple Computer, Inc.
 *
 * 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., 59 Temple Place - Suite 330,
 * Boston, MA 02111-1307, USA.
 *
 */
#ifndef DOM_DocPtr_h
#define DOM_DocPtr_h

namespace DOM {

template <class T> class DocPtr
{
 public:
    DocPtr() : m_ptr(NULL) {}
    DocPtr(T *ptr) : m_ptr(ptr) { if (ptr) ptr->selfOnlyRef(); }
    DocPtr(const DocPtr &o) : m_ptr(o.m_ptr) { if (T *ptr = m_ptr) ptr->selfOnlyRefRef(); }
    ~DocPtr() { if (T *ptr = m_ptr) ptr->selfOnlyDeref(); }
    
    template <class U> DocPtr(const DocPtr<U> &o) : m_ptr(o.get()) { if (T *ptr = m_ptr) ptr->selfOnlyRef(); }
    
    // FIXME: Deprecate in favor of operators below, then remove?
    bool isNull() const { return m_ptr == NULL; }
    bool notNull() const { return m_ptr != NULL; }
    
    // FIXME: Deprecate in favor of operator=, then remove?
    void reset() { if (T *ptr = m_ptr) ptr->selfOnlyDeref(); m_ptr = NULL; }
    void reset(T *o) { if (o) o->selfOnlyRef(); if (T *ptr = m_ptr) ptr->selfOnlyDeref(); m_ptr = o; }

    void resetSkippingRef(T *o) { m_ptr = o; }
    
    T *get() const { return m_ptr; }
    
    T &operator*() const { return *m_ptr; }
    T *operator->() const { return m_ptr; }
    
    bool operator!() const { return m_ptr == NULL; }
    operator bool() const { return m_ptr != NULL; }
    
    DocPtr &operator=(const DocPtr &);
    DocPtr &operator=(T *);
    
 private:
    T *m_ptr;
    
    operator int() const; // deliberately not implemented; helps prevent operator bool from converting to int accidentally
};

template <class T> DocPtr<T> &DocPtr<T>::operator=(const DocPtr<T> &o) 
{
    T *optr = o.m_ptr;
    if (optr)
        optr->selfOnlyRef();
    if (T *ptr = m_ptr)
        ptr->selfOnlyDeref();
    m_ptr = optr;
        return *this;
}

template <class T> inline DocPtr<T> &DocPtr<T>::operator=(T *optr)
{
    if (optr)
        optr->selfOnlyRef();
    if (T *ptr = m_ptr)
        ptr->selfOnlyDeref();
    m_ptr = optr;
    return *this;
}

template <class T> inline bool operator==(const DocPtr<T> &a, const DocPtr<T> &b) 
{ 
    return a.get() == b.get(); 
}

template <class T> inline bool operator==(const DocPtr<T> &a, const T *b) 
{ 
    return a.get() == b; 
}

template <class T> inline bool operator==(const T *a, const DocPtr<T> &b) 
{
    return a == b.get(); 
}

template <class T> inline bool operator!=(const DocPtr<T> &a, const DocPtr<T> &b) 
{ 
    return a.get() != b.get(); 
}

template <class T> inline bool operator!=(const DocPtr<T> &a, const T *b)
{
    return a.get() != b; 
}

template <class T> inline bool operator!=(const T *a, const DocPtr<T> &b) 
{ 
    return a != b.get(); 
}

} // namespace DOM

#endif DOM_DocPtr_h