//-----------------------------------------------------------------------------
//
//  $Logfile:: /Quake 2 Engine/Sin/code/game/stack.h                          $
// $Revision:: 6                                                              $
//   $Author:: Jimdose                                                        $
//     $Date:: 3/02/98 5:27p                                                  $
//
// Copyright (C) 1997 by Ritual Entertainment, Inc.
// All rights reserved.
//
// This source is may not be distributed and/or modified without
// expressly written permission by Ritual Entertainment, Inc.
//
// $Log:: /Quake 2 Engine/Sin/code/game/stack.h                               $
//
// 6     3/02/98 5:27p Jimdose
// Changed stack into a template to make it more flexible.
//
// 5     2/20/98 12:08p Jimdose
// Changed for Q2 dlls
//
// 3     11/17/97 8:17p Jimdose
// Fixed a bug where Pop was checking an uninitialized variable instead of
// testing head.
// Added assertions
//
// 2     11/17/97 7:38p Jimdose
// Created file.
//
// DESCRIPTION:
// Generic Stack object.
//

#ifndef __STACK_H__
#define __STACK_H__

#include "g_local.h"
#include "class.h"

template <class Type>
class StackNode
{
public:
	Type data;
	StackNode *next;

	StackNode( Type d );
};

template <class Type>
inline StackNode<Type>::StackNode( Type d ) : data( d )
{
	next = NULL;
}

template <class Type>
class EXPORT_FROM_DLL Stack
{
private:
	StackNode<Type> *head;

public:
	Stack();
	~Stack<Type>();
	void        Clear( void );
	qboolean Empty( void );
	void        Push( Type data );
	Type        Pop( void );
};

template <class Type>
inline Stack<Type>::Stack()
{
	head = NULL;
}

template <class Type>
inline Stack<Type>::~Stack<Type>()
{
	Clear();
}

template <class Type>
inline void EXPORT_FROM_DLL Stack<Type>::Clear( void )
{
	while( !Empty() )
	{
		Pop();
	}
}

template <class Type>
inline qboolean EXPORT_FROM_DLL Stack<Type>::Empty( void )
{
	if ( head == NULL )
	{
		return true;
	}
	return false;
}

template <class Type>
inline void EXPORT_FROM_DLL Stack<Type>::Push( Type data )
{
	StackNode<Type> *tmp;

	tmp = new StackNode<Type>( data );
	if ( !tmp )
	{
		assert( NULL );
		gi.error( "Stack::Push : Out of memory" );
	}

	tmp->next = head;
	head = tmp;
}

template <class Type>
inline Type EXPORT_FROM_DLL Stack<Type>::Pop( void )
{
	Type ret;
	StackNode<Type> *node;

	if ( !head )
	{
		return NULL;
	}

	node    = head;
	ret = node->data;
	head    = node->next;

	delete node;

	return ret;
}

#endif /* stack.h */
