/*
Open Asset Import Library (assimp)
----------------------------------------------------------------------

Copyright (c) 2006-2012, assimp team
All rights reserved.

Redistribution and use of this software in source and binary forms, 
with or without modification, are permitted provided that the 
following conditions are met:

* Redistributions of source code must retain the above
  copyright notice, this list of conditions and the
  following disclaimer.

* Redistributions in binary form must reproduce the above
  copyright notice, this list of conditions and the
  following disclaimer in the documentation and/or other
  materials provided with the distribution.

* Neither the name of the assimp team, nor the names of its
  contributors may be used to endorse or promote products
  derived from this software without specific prior
  written permission of the assimp team.

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

----------------------------------------------------------------------
*/

/**	@file	ObjTools.h
 *	@brief	Some helpful templates for text parsing
 */
#ifndef OBJ_TOOLS_H_INC
#define OBJ_TOOLS_H_INC

#include "fast_atof.h"

namespace Assimp
{

/**	@brief	Returns true, if the last entry of the buffer is reached.
 *	@param	it	Iterator of current position.
 *	@param	end	Iterator with end of buffer.
 *	@return	true, if the end of the buffer is reached.
 */
template<class char_t>
inline bool isEndOfBuffer(  char_t it, char_t end )
{
	if ( it == end )
	{
		return true;
	}
	else
	{
		end--;
	}
	return ( it == end );	
}

/** @brief	Returns true, if token is a space on any supported platform
*	@param	token	Token to search in
*	@return	true, if token is a space			
*/
inline bool isSeparator( char token )
{
	return ( token == ' ' || 
			token == '\n' || 
			token == '\f' || 
			token == '\r' ||
			token == '\t' );
}

/**	@brief	Returns true, fi token id a new line marking token.
 *	@param	token	Token to search in
 *	@return	true, if token is a newline token.
 */
inline bool isNewLine( char token )
{
	return ( token == '\n' || token == '\f' || token == '\r' );
}

/**	@brief	Returns next word separated by a space
 *	@param	pBuffer	Pointer to data buffer
 *	@param	pEnd	Pointer to end of buffer
 *	@return	Pointer to next space
 */
template<class Char_T>
inline Char_T getNextWord( Char_T pBuffer, Char_T pEnd )
{
	while ( !isEndOfBuffer( pBuffer, pEnd ) )
	{
		if ( !isSeparator( *pBuffer ) || isNewLine( *pBuffer ) )
			break;
		pBuffer++;
	}
	return pBuffer;
}

/**	@brief	Returns pointer a next token
 *	@param	pBuffer	Pointer to data buffer
 *	@param	pEnd	Pointer to end of buffer
 *	@return	Pointer to next token
 */
template<class Char_T>
inline Char_T getNextToken( Char_T pBuffer, Char_T pEnd )
{
	while ( !isEndOfBuffer( pBuffer, pEnd ) )
	{
		if ( isSeparator( *pBuffer ) )
			break;
		pBuffer++;
	}
	return getNextWord( pBuffer, pEnd );
}

/**	@brief	Skips a line
 *	@param	it		Iterator set to current position
 *	@param	end		Iterator set to end of scratch buffer for readout
 *	@param	uiLine	Current linenumber in format
 *	@return	Current-iterator with new position
 */
template<class char_t>
inline char_t skipLine( char_t it, char_t end, unsigned int &uiLine )
{
	while ( !isEndOfBuffer( it, end ) && !isNewLine( *it ) )
		++it;
	if ( it != end )
	{
		++it;
		++uiLine;
	}
	// fix .. from time to time there are spaces at the beginning of a material line
	while ( it != end && (*it == '\t' || *it == ' ') )
		++it;
	return it;
}

/**	@brief	Get a name from the current line. Preserve space in the middle,
 *    but trim it at the end.
 *	@param	it		set to current position
 *	@param	end		set to end of scratch buffer for readout
 *	@param	name	Separated name
 *	@return	Current-iterator with new position
 */
template<class char_t>
inline char_t getName( char_t it, char_t end, std::string &name )
{
	name = "";
	if ( isEndOfBuffer( it, end ) )
		return end;
	
	char *pStart = &( *it );
	while ( !isEndOfBuffer( it, end ) && !isNewLine( *it ) ) {
		++it;
	}

	while(isEndOfBuffer( it, end ) || isNewLine( *it ) || isSeparator(*it)) {
		--it;
	}
	++it;

	// Get name
	// if there is no name, and the previous char is a separator, come back to start
	while (&(*it) < pStart) {
		++it;
	}
	std::string strName( pStart, &(*it) );
	if ( strName.empty() )
		return it;
	else
		name = strName;
	
	return it;
}

/**	@brief	Get next word from given line
 *	@param	it		set to current position
 *	@param	end		set to end of scratch buffer for readout
 *	@param	pBuffer	Buffer for next word
 *	@param	length	Buffer length
 *	@return	Current-iterator with new position
 */
template<class char_t>
inline char_t CopyNextWord( char_t it, char_t end, char *pBuffer, size_t length )
{
	size_t index = 0;
	it = getNextWord<char_t>( it, end );
	while ( !isSeparator( *it ) && !isEndOfBuffer( it, end ) )
	{
		pBuffer[index] = *it ;
		index++;
		if (index == length-1)
			break;
		++it;
	}
	pBuffer[ index ] = '\0';
	return it;
}

/**	@brief	Get next float from given line
 *	@param	it		set to current position
 *	@param	end		set to end of scratch buffer for readout
 *	@param	value	Separated float value.
 *	@return	Current-iterator with new position
 */
template<class char_t>
inline char_t getFloat( char_t it, char_t end, float &value )
{
	static const size_t BUFFERSIZE = 1024;
	char buffer[ BUFFERSIZE ];
	it = CopyNextWord<char_t>( it, end, buffer, BUFFERSIZE );
	value = (float) fast_atof( buffer );

	return it;
}

/**	@brief	Will perform a simple tokenize.
 *	@param	str			String to tokenize.
 *	@param	tokens		Array with tokens, will be empty if no token was found.
 *	@param	delimiters	Delimiter for tokenize.
 *	@return	Number of found token.
 */
template<class string_type>
unsigned int tokenize( const string_type& str, std::vector<string_type>& tokens, 
						 const string_type& delimiters ) 
{
	// Skip delimiters at beginning.
	typename string_type::size_type lastPos = str.find_first_not_of( delimiters, 0 );

	// Find first "non-delimiter".
	typename string_type::size_type pos = str.find_first_of( delimiters, lastPos );
	while ( string_type::npos != pos || string_type::npos != lastPos )
	{
		// Found a token, add it to the vector.
		string_type tmp = str.substr(lastPos, pos - lastPos);
		if ( !tmp.empty() && ' ' != tmp[ 0 ] )
			tokens.push_back( tmp );

		// Skip delimiters.  Note the "not_of"
		lastPos = str.find_first_not_of( delimiters, pos );

		// Find next "non-delimiter"
		pos = str.find_first_of( delimiters, lastPos );
	}

	return static_cast<unsigned int>( tokens.size() );
}

} // Namespace Assimp

#endif
