//%2006////////////////////////////////////////////////////////////////////////
//
// Copyright (c) 2000, 2001, 2002 BMC Software; Hewlett-Packard Development
// Company, L.P.; IBM Corp.; The Open Group; Tivoli Systems.
// Copyright (c) 2003 BMC Software; Hewlett-Packard Development Company, L.P.;
// IBM Corp.; EMC Corporation, The Open Group.
// Copyright (c) 2004 BMC Software; Hewlett-Packard Development Company, L.P.;
// IBM Corp.; EMC Corporation; VERITAS Software Corporation; The Open Group.
// Copyright (c) 2005 Hewlett-Packard Development Company, L.P.; IBM Corp.;
// EMC Corporation; VERITAS Software Corporation; The Open Group.
// Copyright (c) 2006 Hewlett-Packard Development Company, L.P.; IBM Corp.;
// EMC Corporation; Symantec Corporation; The Open Group.
//
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to
// deal in the Software without restriction, including without limitation the
// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
// sell copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// THE ABOVE COPYRIGHT NOTICE AND THIS PERMISSION NOTICE SHALL BE INCLUDED IN
// ALL COPIES OR SUBSTANTIAL PORTIONS OF THE SOFTWARE. THE SOFTWARE IS PROVIDED
// "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT
// LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR
// PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
// HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
// ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
// WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
//
//==============================================================================
//
// Author: Michael E. Brasher, Inova Europe (mike-brasher@austin.rr.com)
//
//%/////////////////////////////////////////////////////////////////////////////

#ifndef Pegasus_ArrayIterator_h
#define Pegasus_ArrayIterator_h

#include <Pegasus/Common/Array.h>

PEGASUS_NAMESPACE_BEGIN

//
// This class provides a faster way of iterating arrays. Due to the expense
// of calling operator[], iteration is slower than necessary. Consider this 
// example:
//
//     Array<Uint32> array;
//     Uint32 sum = 0;
//
//     for (Uint32 i = 0, n = array.size(); i < n; i++)
//         sum += array[i];
//
// Every use of array[i] results in a function call that checks for a bounds
// violation. We can see that an array bounds violation is impossible in this
// case. We can use the ConstArrayIterator class to eliminate this overhead.
// 
//     Array<Uint32> array;
//     Uint32 sum = 0;
//
//     ConstArrayIterator<Uint32> iterator(array);
//
//     for (Uint32 i = 0; i < iterator.size(); i++)
//         sum += iterator[i];
//
// The constructor pre-saves the array size and data before entering the loop
// so that iterator.size() and iterator[i] are trivial inline functions that
// access these members.
//
template<class T>
class ConstArrayIterator
{
public:

    ConstArrayIterator(const Array<T>& x) : _data(x.getData()), _size(x.size()) 
    { 
    }

    Uint32 size() const 
    { 
	return _size; 
    }

    const T& operator[](Uint32 i)  const 
    { 
	PEGASUS_DEBUG_ASSERT(i < _size);
	return _data[i]; 
    }

private:

    ConstArrayIterator& operator=(const ConstArrayIterator<T>& x);
    ConstArrayIterator(const ConstArrayIterator<T>& x);

    const T* _data;
    Uint32 _size;
};

//
// This class is similar to ConstArrayIterator except it provides a non-const
// version of operator[].
//
template<class T>
class ArrayIterator
{
public:

    ArrayIterator(Array<T>& x) : _data((T*)x.getData()), _size(x.size()) 
    { 
    }

    Uint32 size() const 
    { 
	return _size; 
    }

    const T& operator[](Uint32 i)  const 
    { 
	PEGASUS_DEBUG_ASSERT(i < _size);
	return _data[i]; 
    }

    T& operator[](Uint32 i)
    {
	PEGASUS_DEBUG_ASSERT(i < _size);
	return _data[i]; 
    }

    //
    // The reset() methode set the Iterators object members to new 
    // data pointer and size of a given Array<T>
    //
    void reset(Array<T>& x)
    { 
        _data = (T*)x.getData();
        _size = x.size();
    }

private:

    ArrayIterator& operator=(const ArrayIterator<T>& x);
    ArrayIterator(const ArrayIterator<T>& x);

    T* _data;
    Uint32 _size;
};

PEGASUS_NAMESPACE_END

#endif /* Pegasus_ArrayIterator_h */