/*
 * Copyright (C) 2007-2010 Xagasoft, All rights reserved.
 *
 * This file is part of the libbu++ library and is released under the
 * terms of the license contained in the file LICENSE.
 */

#ifndef BU_UTIL_H
#define BU_UTIL_H

#ifndef NULL
# define NULL 0
#endif

/* I borrowed this from someone who borrowed it from glib who borrowed it
 * from...
 */
#if (__GNUC__ > 3 || (__GNUC__ == 3 && __GNUC_MINOR__ >= 1))
# define DEPRECATED  __attribute__((__deprecated__))
#else
# define DEPRECATED
#endif /* __GNUC__ */

#include <string.h>

namespace Bu
{
	/**
	 * Swap the value of two variables, uses references, so it's pretty safe.
	 * Objects passed in must support a basic assignemnt operator (=);
	 *@param a Variable to recieve the value of parameter b
	 *@param b Variable to recieve the value of parameter a
	 */
	template<typename item>
	void swap( item &a, item &b )
	{
		item tmp = a;
		a = b;
		b = tmp;
	}

	/**
	 * Finds the lesser of the two objects, objects passed in must be
	 * less-than-comparable.
	 *@param a A value to test.
	 *@param b Another value to test.
	 *@returns A reference to the lesser of a or b.
	 */
	template<typename item>
	const item &min( const item &a, const item &b )
	{
		return a<b?a:b;
	}
	
	/**
	 * Finds the lesser of the two objects, objects passed in must be
	 * less-than-comparable.
	 *@param a A value to test.
	 *@param b Another value to test.
	 *@returns A reference to the lesser of a or b.
	 */
	template<typename item>
	item &min( item &a, item &b )
	{
		return a<b?a:b;
	}
	
	/**
	 * Finds the greater of the two objects, objects passed in must be
	 * less-than-comparable.
	 *@param a A value to test.
	 *@param b Another value to test.
	 *@returns A reference to the greater of a or b.
	 */
	template<typename item>
	const item &max( const item &a, const item &b )
	{
		return b<a?a:b;
	}
	
	/**
	 * Finds the greater of the two objects, objects passed in must be
	 * less-than-comparable.
	 *@param a A value to test.
	 *@param b Another value to test.
	 *@returns A reference to the greater of a or b.
	 */
	template<typename item>
	item &max( item &a, item &b )
	{
		return b<a?a:b;
	}
	
	/**
	 * Given three objects this finds the one between the other two.
	 *@param a A value to test.
	 *@param b Another value to test.
	 *@param c Yet another value to test.
	 *@returns A reference to the mid-value of a, b, and c.
	 */
	template<typename item>
	const item &mid( const item &a, const item &b, const item &c )
	{
		return min( max( a, b ), c );
	}
		
	/**
	 * Given three objects this finds the one between the other two.
	 *@param a A value to test.
	 *@param b Another value to test.
	 *@param c Yet another value to test.
	 *@returns A reference to the mid-value of a, b, and c.
	 */
	template<typename item>
	item &mid( item &a, item &b, item &c )
	{
		return min( max( a, b ), c );
	}
	
	//
	//  Basic comparison functors
	//
	/**
	 * Simple less-than comparison functor.  Objects being used should be
	 * less-than-comparable.
	 */
	template<typename item>
	struct __basicLTCmp
	{
		bool operator()( const item &a, const item &b )
		{
			return a < b;
		}
	};
	
	/**
	 * Simple greater-than comparison functor.  Objects being used should be
	 * greater-than-comparable.
	 */
	template<typename item>
	struct __basicGTCmp
	{
		bool operator()( const item &a, const item &b )
		{
			return a > b;
		}
	};

	/**
	 * As __basicLTCmp but dereferences the passed in pointers before comparing.
	 */
	template<typename item>
	struct __basicPtrLTCmp
	{
		bool operator()( const item &a, const item &b )
		{
			return *a < *b;
		}
	};
	
	/**
	 * As __basicGTCmp but dereferences the passed in pointers before comparing.
	 */
	template<typename item>
	struct __basicPtrGTCmp
	{
		bool operator()( const item &a, const item &b )
		{
			return *a > *b;
		}
	};

	/**
	 * Get the number of days in the month in the gregorian calendar, taking
	 * leap years into account.
	 */
	int getDaysInMonth( int iMonth, int iYear );

	void memcpy( void *pDest, const void *pSrc, size_t iBytes );
};

#endif