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

Copyright (c) 2006-2008, ASSIMP Development 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 Development 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.
---------------------------------------------------------------------------
*/

#include "AssimpPCH.h"
#ifndef ASSIMP_BUILD_NO_OBJ_IMPORTER

#include "ObjFileParser.h"
#include "ObjFileMtlImporter.h"
#include "ObjTools.h"
#include "ObjFileData.h"
#include "fast_atof.h"

#include "DefaultIOSystem.h"

namespace Assimp	{
// -------------------------------------------------------------------
const std::string ObjFileParser::DEFAULT_MATERIAL = AI_DEFAULT_MATERIAL_NAME; 
// fix: changed that to our standard default name

// -------------------------------------------------------------------
//	Constructor with loaded data and directories.
ObjFileParser::ObjFileParser(std::vector<char> &Data, 
							 const std::string &strAbsPath, 
							 const std::string &strModelName) :
	m_strAbsPath(strAbsPath),
	m_DataIt(Data.begin()),
	m_DataItEnd(Data.end()),
	m_pModel(NULL),
	m_uiLine(0)
{
	// Create the model instance to store all the data
	m_pModel = new ObjFile::Model();
	m_pModel->m_ModelName = strModelName;
	
	m_pModel->m_pDefaultMaterial = new ObjFile::Material();
	m_pModel->m_pDefaultMaterial->MaterialName.Set( DEFAULT_MATERIAL );
	m_pModel->m_MaterialLib.push_back( DEFAULT_MATERIAL );
	m_pModel->m_MaterialMap[ DEFAULT_MATERIAL ] = m_pModel->m_pDefaultMaterial;
	
	// Start parsing the file
	parseFile();
}

// -------------------------------------------------------------------
ObjFileParser::~ObjFileParser()
{
	delete m_pModel->m_pDefaultMaterial;
	m_pModel->m_pDefaultMaterial = NULL;

	delete m_pModel;
	m_pModel = NULL;
}

// -------------------------------------------------------------------
ObjFile::Model *ObjFileParser::GetModel() const
{
	return m_pModel;
}

// -------------------------------------------------------------------
void ObjFileParser::parseFile()
{
	if (m_DataIt == m_DataItEnd)
		return;

	while (m_DataIt != m_DataItEnd)
	{
		switch (*m_DataIt)
		{
		case 'v': // Parse a vertex texture coordinate
			{
				++m_DataIt;
				if (*m_DataIt == ' ')
				{
					// Read in vertex definition
					getVector3(m_pModel->m_Vertices);
				}
				else if (*m_DataIt == 't')
				{
					// Read in texture coordinate (2D)
					++m_DataIt;
					getVector2(m_pModel->m_TextureCoord);
				}
				else if (*m_DataIt == 'n')
				{
					// Read in normal vector definition
					++m_DataIt;
					getVector3(m_pModel->m_Normals);
				}
			}
			break;

		case 'f': // Parse a face
			{
				getFace();
			}
			break;

		case '#': // Parse a comment
			{
				getComment();
			}
			break;

		case 'u': // Parse a material desc. setter
			{
				getMaterialDesc();
			}
			break;

		case 'm': // Parse a material library
			{
				getMaterialLib();
			}
			break;

		case 'g': // Parse group name
			{
				getGroupName();
			}
			break;

		case 's': // Parse group number
			{
				getGroupNumber();
			}
			break;

		case 'o': // Parse object name
			{
				getObjectName();
			}
			break;
		
		default:
			{
				m_DataIt = skipLine<DataArrayIt>( m_DataIt, m_DataItEnd, m_uiLine );
			}
			break;
		}
	}
}

// -------------------------------------------------------------------
//	Copy the next word in a temporary buffer
void ObjFileParser::copyNextWord(char *pBuffer, size_t length)
{
	size_t index = 0;
	m_DataIt = getNextWord<DataArrayIt>(m_DataIt, m_DataItEnd);
	while (!isSpace(*m_DataIt) && m_DataIt != m_DataItEnd)
	{
		pBuffer[index] = *m_DataIt;
		index++;
		if (index == length-1)
			break;
		++m_DataIt;
	}
	pBuffer[index] = '\0';
}

// -------------------------------------------------------------------
// Copy the next line into a temporary buffer
void ObjFileParser::copyNextLine(char *pBuffer, size_t length)
{
	size_t index = 0;
	while (m_DataIt != m_DataItEnd)
	{
		if (*m_DataIt == '\n' || *m_DataIt == '\r')
			break;
		assert (index+1 <= length);
		pBuffer[ index ] = *m_DataIt;
		++index;
		++m_DataIt;
	}
	pBuffer[ index ] = '\0';
}

// -------------------------------------------------------------------
//	Get values for a new 3D vector instance
void ObjFileParser::getVector3(std::vector<aiVector3D*> &point3d_array)
{
	float x, y, z;
	copyNextWord(m_buffer, BUFFERSIZE);
	x = (float) fast_atof(m_buffer);	
	
	copyNextWord(m_buffer, BUFFERSIZE);
	y = (float) fast_atof(m_buffer);

	copyNextWord(m_buffer, BUFFERSIZE);
	z = (float) fast_atof(m_buffer);

	point3d_array.push_back(new aiVector3D(x,y,z));
	//skipLine();
	m_DataIt = skipLine<DataArrayIt>( m_DataIt, m_DataItEnd, m_uiLine );
}

// -------------------------------------------------------------------
//	Get values for a new 2D vector instance
void ObjFileParser::getVector2( std::vector<aiVector2D*> &point2d_array )
{
	float x, y;
	copyNextWord(m_buffer, BUFFERSIZE);
	x = (float) fast_atof(m_buffer);	
	
	copyNextWord(m_buffer, BUFFERSIZE);
	y = (float) fast_atof(m_buffer);

	point2d_array.push_back(new aiVector2D(x, y));

	m_DataIt = skipLine<DataArrayIt>( m_DataIt, m_DataItEnd, m_uiLine );
}

// -------------------------------------------------------------------
//	Get values for a new face instance
void ObjFileParser::getFace()
{
	copyNextLine(m_buffer, BUFFERSIZE);
	if (m_DataIt == m_DataItEnd)
		return;

	char *pPtr = m_buffer;
	char *pEnd = &pPtr[BUFFERSIZE];
	pPtr = getNextToken<char*>(pPtr, pEnd);
	if (pPtr == '\0')
		return;

	std::vector<unsigned int> *pIndices = new std::vector<unsigned int>;
	std::vector<unsigned int> *pTexID = new std::vector<unsigned int>;
	std::vector<unsigned int> *pNormalID = new std::vector<unsigned int>;
	bool hasNormal = false;
	

	bool vt = (!m_pModel->m_TextureCoord.empty());
	bool vn = (!m_pModel->m_Normals.empty());
	int iStep = 0, iPos = 0;
	while (pPtr != pEnd)
	{
		iStep = 1;
		if (*pPtr == '\0')
			break;

		if (*pPtr=='\r')
			break;

		if (*pPtr=='/' )
		{
			if (iPos == 0)
			{
				//if there are no texturecoordinates in the obj file but normals
				if (!vt && vn) {
					iPos = 1;
					iStep++;
				}
			}
			iPos++;
		}
		else if (isSpace(*pPtr))
		{
			iPos = 0;
		}
		else 
		{
			//OBJ USES 1 Base ARRAYS!!!!
			const int iVal = atoi( pPtr );
			int tmp = iVal;
			while ((tmp = tmp / 10)!=0)
				++iStep;

			if ( 0 != iVal )
			{
				// Store parsed index
				if ( 0 == iPos )
				{
					pIndices->push_back( iVal-1 );
				}
				else if ( 1 == iPos )
				{	
					pTexID->push_back( iVal-1 );
				}
				else if ( 2 == iPos )
				{
					pNormalID->push_back( iVal-1 );
					hasNormal = true;
				}
				else
				{
					reportErrorTokenInFace();
				}
			}
		}
		for ( int i=0; i<iStep; i++ )
			++pPtr;
	}

	ObjFile::Face *face = new ObjFile::Face(pIndices, pNormalID, pTexID);
	
	// Set active material, if one set
	if (NULL != m_pModel->m_pCurrentMaterial) 
		face->m_pMaterial = m_pModel->m_pCurrentMaterial;
	else 
		face->m_pMaterial = m_pModel->m_pDefaultMaterial;

	// Create a default object, if nothing there
	if ( NULL == m_pModel->m_pCurrent )
		createObject("defaultobject");

	// Store the new instance
	m_pModel->m_pCurrent->m_Faces.push_back(face);
	
	// Assign face to mesh
	if ( NULL == m_pModel->m_pCurrentMesh )
	{
		m_pModel->m_pCurrentMesh = new ObjFile::Mesh();
		m_pModel->m_Meshes.push_back( m_pModel->m_pCurrentMesh );
	}
	
	// Store the face
	m_pModel->m_pCurrentMesh->m_Faces.push_back( face );
	m_pModel->m_pCurrentMesh->m_uiNumIndices += (unsigned int)face->m_pVertices->size();
	m_pModel->m_pCurrentMesh->m_uiUVCoordinates[ 0 ] += (unsigned int)face->m_pTexturCoords[0].size(); 
	if(!m_pModel->m_pCurrentMesh->m_hasNormals && hasNormal) {
		m_pModel->m_pCurrentMesh->m_hasNormals = true;
	}
	// Skip the rest of the line
	m_DataIt = skipLine<DataArrayIt>( m_DataIt, m_DataItEnd, m_uiLine );
}

// -------------------------------------------------------------------
//	Get values for a new material description
void ObjFileParser::getMaterialDesc()
{
	// Get next data for material data
	m_DataIt = getNextToken<DataArrayIt>(m_DataIt, m_DataItEnd);
	if (m_DataIt == m_DataItEnd)
		return;

	char *pStart = &(*m_DataIt);
	while ( !isSpace(*m_DataIt) && m_DataIt != m_DataItEnd )
		++m_DataIt;

	// Get name
	std::string strName(pStart, &(*m_DataIt));
	if ( strName.empty())
		return;

	// Search for material
	std::map<std::string, ObjFile::Material*>::iterator it = m_pModel->m_MaterialMap.find( strName );
	if ( it == m_pModel->m_MaterialMap.end() )
	{
		// Not found, use default material
		m_pModel->m_pCurrentMaterial = m_pModel->m_pDefaultMaterial;
		m_pModel->m_pCurrentMesh = new ObjFile::Mesh();
		m_pModel->m_Meshes.push_back( m_pModel->m_pCurrentMesh );
		m_pModel->m_pCurrentMesh->m_uiMaterialIndex = getMaterialIndex( DEFAULT_MATERIAL );
	}
	else
	{
		// Found, using detected material
		m_pModel->m_pCurrentMaterial = (*it).second;

		// Create a new mesh for a new material
		m_pModel->m_pCurrentMesh = new ObjFile::Mesh();
		m_pModel->m_Meshes.push_back( m_pModel->m_pCurrentMesh );
		m_pModel->m_pCurrentMesh->m_uiMaterialIndex = getMaterialIndex( strName );
	}

	// Skip rest of line
	m_DataIt = skipLine<DataArrayIt>( m_DataIt, m_DataItEnd, m_uiLine );
}

// -------------------------------------------------------------------
//	Get a comment, values will be skipped
void ObjFileParser::getComment()
{
	while (true)
	{
		if ('\n' == (*m_DataIt) || m_DataIt == m_DataItEnd) 
		{
			++m_DataIt;
			break;
		}
		else
		{
			++m_DataIt;
		}
	}
}

// -------------------------------------------------------------------
//	Get material library from file.
void ObjFileParser::getMaterialLib()
{
	// Translate tuple
	m_DataIt = getNextToken<DataArrayIt>(m_DataIt, m_DataItEnd);
	if (m_DataIt ==  m_DataItEnd)
		return;
	
	char *pStart = &(*m_DataIt);
	while (!isNewLine(*m_DataIt))
		m_DataIt++;
	
	// TODO: fix path construction
	// CLEANUP ... who is resposible for *two* identical DefaultIOSystems 
	// where the IOSystem passed to ReadFile() should be used???

	// Check for existence
	DefaultIOSystem IOSystem;
	std::string strMatName(pStart, &(*m_DataIt));
	std::string absName = m_strAbsPath + IOSystem.getOsSeparator() + strMatName;
	if ( !IOSystem.Exists( absName.c_str()) )
	{
		m_DataIt = skipLine<DataArrayIt>( m_DataIt, m_DataItEnd, m_uiLine );
		return;
	}

	// Extract the extention
	std::string strExt("");
	extractExtension( strMatName, strExt );
	static const std::string mat = "mtl";

	// Load the material library
	DefaultIOSystem FileSystem;
	IOStream *pFile = FileSystem.Open(absName.c_str());
	if (0L != pFile)
	{
		// Import material library data from file
		size_t size = pFile->FileSize();
		std::vector<char> buffer;
		buffer.resize( size );
		pFile->Read( &buffer[ 0 ], sizeof( char ), size );
		FileSystem.Close( pFile );

		// Importing the material library 
		ObjFileMtlImporter mtlImporter( buffer, absName, m_pModel );			
	}
	
	// Skip rest of line
	m_DataIt = skipLine<DataArrayIt>( m_DataIt, m_DataItEnd, m_uiLine );
}

// -------------------------------------------------------------------
//	Set a new material definition as the current material.
void ObjFileParser::getNewMaterial()
{
	m_DataIt = getNextToken<DataArrayIt>(m_DataIt, m_DataItEnd);
	m_DataIt = getNextWord<DataArrayIt>(m_DataIt, m_DataItEnd);
	if ( m_DataIt == m_DataItEnd )
		return;

	char *pStart = &(*m_DataIt);
	std::string strMat(pStart, *m_DataIt);
	while (isSpace(*m_DataIt))
		m_DataIt++;
	std::map<std::string, ObjFile::Material*>::iterator it = m_pModel->m_MaterialMap.find( strMat );
	if (it == m_pModel->m_MaterialMap.end())
	{
		// Show a warning, if material was not found
		std::string strWarn ("Unsupported material requested: ");
		strWarn += strMat;
		std::cerr << "Warning : " << strWarn << std::endl;
		m_pModel->m_pCurrentMaterial = m_pModel->m_pDefaultMaterial;
	}
	else
	{
		// Set new material
		m_pModel->m_pCurrentMaterial = (*it).second;
		m_pModel->m_pCurrentMesh->m_uiMaterialIndex = getMaterialIndex( strMat );
	}

	m_DataIt = skipLine<DataArrayIt>( m_DataIt, m_DataItEnd, m_uiLine );
}

// -------------------------------------------------------------------
int ObjFileParser::getMaterialIndex( const std::string &strMaterialName )
{
	int mat_index = -1;
	if ( strMaterialName.empty() )
		return mat_index;
		for (size_t index = 0; index < m_pModel->m_MaterialLib.size(); ++index)
		{
			if ( strMaterialName == m_pModel->m_MaterialLib[ index ])
			{
				mat_index = (int)index;
				break;
			}
		}
	return mat_index;
}

// -------------------------------------------------------------------
//	Getter for a group name.  
void ObjFileParser::getGroupName()
{
	// Get next word from data buffer
	m_DataIt = getNextToken<DataArrayIt>(m_DataIt, m_DataItEnd);
	m_DataIt = getNextWord<DataArrayIt>(m_DataIt, m_DataItEnd);
	if ( m_DataIt == m_DataItEnd )
		return;

	// Store groupname in group library 
	char *pStart = &(*m_DataIt);
	while (!isSpace(*m_DataIt))
		m_DataIt++;
	std::string strGroupName(pStart, &(*m_DataIt));

	// Change active group, if necessary
	if (m_pModel->m_strActiveGroup != strGroupName)
	{
		// Search for already existing entry
		ObjFile::Model::ConstGroupMapIt it = m_pModel->m_Groups.find(&strGroupName);
		
		// New group name, creating a new entry
		//ObjFile::Object *pObject = m_pModel->m_pCurrent;
		if (it == m_pModel->m_Groups.end())
		{
			std::vector<unsigned int> *pFaceIDArray = new std::vector<unsigned int>;
			m_pModel->m_Groups[ &strGroupName ] = pFaceIDArray;
			m_pModel->m_pGroupFaceIDs = (pFaceIDArray);
		}
		else
		{
			m_pModel->m_pGroupFaceIDs = (*it).second;
		}
		m_pModel->m_strActiveGroup = strGroupName;
	}
	m_DataIt = skipLine<DataArrayIt>( m_DataIt, m_DataItEnd, m_uiLine );
}

// -------------------------------------------------------------------
//	Not supported
void ObjFileParser::getGroupNumber()
{
	// Not used

	m_DataIt = skipLine<DataArrayIt>( m_DataIt, m_DataItEnd, m_uiLine );
}

// -------------------------------------------------------------------
//	Stores values for a new object instance, name will be used to 
//	identify it.
void ObjFileParser::getObjectName()
{
	m_DataIt = getNextToken<DataArrayIt>(m_DataIt, m_DataItEnd);
	if (m_DataIt == m_DataItEnd)
		return;
	char *pStart = &(*m_DataIt);
	while (!isSpace(*m_DataIt))
		m_DataIt++;

	std::string strObjectName(pStart, &(*m_DataIt));
	if (!strObjectName.empty()) 
	{
		// Reset current object
		m_pModel->m_pCurrent = NULL;
		
		// Search for actual object
		for (std::vector<ObjFile::Object*>::const_iterator it = m_pModel->m_Objects.begin();
			it != m_pModel->m_Objects.end();
			++it)
		{
			if ((*it)->m_strObjName == strObjectName)
			{
				m_pModel->m_pCurrent = *it;
				break;
			}
		}

		// Allocate a new object, if current one wasn´t found before
		if (m_pModel->m_pCurrent == NULL)
		{
			createObject(strObjectName);
			/*m_pModel->m_pCurrent = new ObjFile::Object();
			m_pModel->m_pCurrent->m_strObjName = strObjectName;
			m_pModel->m_Objects.push_back(m_pModel->m_pCurrent);*/
		}
	}
	m_DataIt = skipLine<DataArrayIt>( m_DataIt, m_DataItEnd, m_uiLine );
}
// -------------------------------------------------------------------
//	Creates a new object instance
void ObjFileParser::createObject(const std::string &strObjectName)
{
	ai_assert (NULL != m_pModel);
	ai_assert (!strObjectName.empty());

	m_pModel->m_pCurrent = new ObjFile::Object();
	m_pModel->m_pCurrent->m_strObjName = strObjectName;
	m_pModel->m_Objects.push_back(m_pModel->m_pCurrent);
}

// -------------------------------------------------------------------
//	Shows an error in parsing process.
void ObjFileParser::reportErrorTokenInFace()
{		
	std::string strErr("");
	
	m_DataIt = skipLine<DataArrayIt>( m_DataIt, m_DataItEnd, m_uiLine );
	std::cerr <<  "Not supported token in face desc. detected : " << strErr << std::endl;
}

// -------------------------------------------------------------------
//	Extracts the extention from a filename
void ObjFileParser::extractExtension(const std::string &strFile, 
									 std::string &strExt)
{
	strExt = "";
	if (strFile.empty())
		return;

	// Search for extention delimiter
	std::string::size_type pos = strFile.find_last_of(".");
	if ( pos == std::string::npos )
		return;

	strExt = strFile.substr(pos, strFile.size() - pos);
}
// -------------------------------------------------------------------

}	// Namespace Assimp

#endif // !! ASSIMP_BUILD_NO_OBJ_IMPORTER