/*
---------------------------------------------------------------------------
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.
---------------------------------------------------------------------------
*/

/** @file Implementation of the IrrMesh importer class */

#include "AssimpPCH.h"


#include "IRRMeshLoader.h"
#include "ParsingUtils.h"
#include "fast_atof.h"

using namespace Assimp;


// ------------------------------------------------------------------------------------------------
// Constructor to be privately used by Importer
IRRMeshImporter::IRRMeshImporter()
{
	// nothing to do here
}

// ------------------------------------------------------------------------------------------------
// Destructor, private as well 
IRRMeshImporter::~IRRMeshImporter()
{
	// nothing to do here
}

// ------------------------------------------------------------------------------------------------
// Returns whether the class can handle the format of the given file. 
bool IRRMeshImporter::CanRead( const std::string& pFile, IOSystem* pIOHandler) const
{
	/* NOTE: A simple check for the file extension is not enough
	 * here. Irrmesh and irr are easy, but xml is too generic
	 * and could be collada, too. So we need to open the file and
	 * search for typical tokens.
	 */

	std::string::size_type pos = pFile.find_last_of('.');

	// no file extension - can't read
	if( pos == std::string::npos)
		return false;

	std::string extension = pFile.substr( pos);
	for (std::string::iterator i = extension.begin(); i != extension.end();++i)
		*i = ::tolower(*i);

	if (extension == ".irrmesh")return true;
	else if (extension == ".xml")
	{
		/*  If CanRead() is called to check whether the loader
		 *  supports a specific file extension in general we
		 *  must return true here.
		 */
		if (!pIOHandler)return true;
		const char* tokens[] = {"irrlicht","irrmesh"};
		return SearchFileHeaderForToken(pIOHandler,pFile,tokens,2);
	}
	return false;
}

// ------------------------------------------------------------------------------------------------
// read a property in hexadecimal format (i.e. ffffffff)
void IRRMeshImporter::ReadHexProperty    (HexProperty&    out)
{
	for (int i = 0; i < reader->getAttributeCount();++i)
	{
		if (!ASSIMP_stricmp(reader->getAttributeName(i),"name"))
		{
			out.name = std::string( reader->getAttributeValue(i) );
		}
		else if (!ASSIMP_stricmp(reader->getAttributeName(i),"value"))
		{
			// parse the hexadecimal value
			out.value = strtol16(reader->getAttributeValue(i));
		}
	}
}

// ------------------------------------------------------------------------------------------------
// read a string property
void IRRMeshImporter::ReadStringProperty (StringProperty& out)
{
	for (int i = 0; i < reader->getAttributeCount();++i)
	{
		if (!ASSIMP_stricmp(reader->getAttributeName(i),"name"))
		{
			out.name = std::string( reader->getAttributeValue(i) );
		}
		else if (!ASSIMP_stricmp(reader->getAttributeName(i),"value"))
		{
			// simple copy the string
			out.value = std::string (reader->getAttributeValue(i));
		}
	}
}

// ------------------------------------------------------------------------------------------------
// read a boolean property
void IRRMeshImporter::ReadBoolProperty   (BoolProperty&   out)
{
	for (int i = 0; i < reader->getAttributeCount();++i)
	{
		if (!ASSIMP_stricmp(reader->getAttributeName(i),"name"))
		{
			out.name = std::string( reader->getAttributeValue(i) );
		}
		else if (!ASSIMP_stricmp(reader->getAttributeName(i),"value"))
		{
			// true or false, case insensitive
			out.value = (ASSIMP_stricmp( reader->getAttributeValue(i), 
				"true") ? false : true);
		}
	}
}

// ------------------------------------------------------------------------------------------------
// read a float property
void IRRMeshImporter::ReadFloatProperty  (FloatProperty&  out)
{
	for (int i = 0; i < reader->getAttributeCount();++i)
	{
		if (!ASSIMP_stricmp(reader->getAttributeName(i),"name"))
		{
			out.name = std::string( reader->getAttributeValue(i) );
		}
		else if (!ASSIMP_stricmp(reader->getAttributeName(i),"value"))
		{
			// true or false, case insensitive
			out.value = fast_atof( reader->getAttributeValue(i) );
		}
	}
}

// ------------------------------------------------------------------------------------------------
void ColorFromARGBPacked(uint32_t in, aiColor4D& clr)
{
	clr.a = ((in >> 24) & 0xff) / 255.f;
	clr.r = ((in >> 16) & 0xff) / 255.f;
	clr.g = ((in >>  8) & 0xff) / 255.f;
	clr.b = ((in      ) & 0xff) / 255.f;
}

// ------------------------------------------------------------------------------------------------
int ConvertMappingMode(const std::string& mode)
{
	if (mode == "texture_clamp_repeat")
		return aiTextureMapMode_Wrap;
	else if (mode == "texture_clamp_mirror")
		return aiTextureMapMode_Mirror;

	return aiTextureMapMode_Clamp;
}

// ------------------------------------------------------------------------------------------------
// Parse a material from the XML file
aiMaterial* IRRMeshImporter::ParseMaterial(unsigned int& matFlags)
{
	MaterialHelper* mat = new MaterialHelper();
	aiColor4D clr;
	aiString s;

	matFlags = 0;

	// Continue reading from the file
	while (reader->read())
	{
		switch (reader->getNodeType())
		{
		case EXN_ELEMENT:

			// Hex properties
			if (!ASSIMP_stricmp(reader->getNodeName(),"color"))
			{
				HexProperty prop;
				ReadHexProperty(prop);
				if (prop.name == "Diffuse")
				{
					ColorFromARGBPacked(prop.value,clr);
					mat->AddProperty(&clr,1,AI_MATKEY_COLOR_DIFFUSE);
				}
				else if (prop.name == "Ambient")
				{
					ColorFromARGBPacked(prop.value,clr);
					mat->AddProperty(&clr,1,AI_MATKEY_COLOR_AMBIENT);
				}
				else if (prop.name == "Specular")
				{
					ColorFromARGBPacked(prop.value,clr);
					mat->AddProperty(&clr,1,AI_MATKEY_COLOR_SPECULAR);
				}
				else if (prop.name == "Emissive")
				{
					ColorFromARGBPacked(prop.value,clr);
					mat->AddProperty(&clr,1,AI_MATKEY_COLOR_EMISSIVE);
				}
			}
			// Float properties
			else if (!ASSIMP_stricmp(reader->getNodeName(),"float"))
			{
				FloatProperty prop;
				ReadFloatProperty(prop);
				if (prop.name == "Shininess")
				{
					mat->AddProperty(&prop.value,1,AI_MATKEY_SHININESS);
				}
			}
			// Bool properties
			else if (!ASSIMP_stricmp(reader->getNodeName(),"bool"))
			{
				BoolProperty prop;
				ReadBoolProperty(prop);
				if (prop.name == "Wireframe")
				{
					int val = (prop.value ? true : false);
					mat->AddProperty(&val,1,AI_MATKEY_ENABLE_WIREFRAME);
				}
				else if (prop.name == "GouraudShading")
				{
					int val = (prop.value ? aiShadingMode_Gouraud 
						: aiShadingMode_NoShading);
					mat->AddProperty(&val,1,AI_MATKEY_SHADING_MODEL);
				}
			}
			// String properties - textures and texture related properties
			else if (!ASSIMP_stricmp(reader->getNodeName(),"texture") ||
				     !ASSIMP_stricmp(reader->getNodeName(),"enum"))
			{
				StringProperty prop;
				ReadStringProperty(prop);
				int cnt = 0;

				if (prop.value.length())
				{
					// material type (shader)
					if (prop.name == "Type")
					{
						if (prop.value == "trans_vertex_alpha")
						{
							matFlags = AI_IRRMESH_MAT_trans_vertex_alpha;
						}
						else if (prop.value == "lightmap")
						{
							matFlags = AI_IRRMESH_MAT_lightmap;
						}
						else if (prop.value == "lightmap_m2")
						{
							matFlags = AI_IRRMESH_MAT_lightmap_m2;
						}
						else if (prop.value == "lightmap_m4")
						{
							matFlags = AI_IRRMESH_MAT_lightmap_m4;
						}
					}

					// Up to 4 texture channels are supported
					else if (prop.name == "Texture1")
					{
						++cnt;
						s.Set(prop.value);
						mat->AddProperty(&s,AI_MATKEY_TEXTURE_DIFFUSE(0));
					}
					else if (prop.name == "Texture2")
					{
						++cnt;
						s.Set(prop.value);
						mat->AddProperty(&s,AI_MATKEY_TEXTURE_DIFFUSE(1));
					}
					else if (prop.name == "Texture3")
					{
						++cnt;
						s.Set(prop.value);
						mat->AddProperty(&s,AI_MATKEY_TEXTURE_DIFFUSE(2));
					}
					else if (prop.name == "Texture4" )
					{
						++cnt;
						s.Set(prop.value);
						mat->AddProperty(&s,AI_MATKEY_TEXTURE_DIFFUSE(3));
					}

					// Texture mapping options
					if (prop.name == "TextureWrap1" && cnt >= 1)
					{
						int map = ConvertMappingMode(prop.value);
						mat->AddProperty(&map,1,AI_MATKEY_MAPPINGMODE_U_DIFFUSE(0));
						mat->AddProperty(&map,1,AI_MATKEY_MAPPINGMODE_V_DIFFUSE(0));
					}
					else if (prop.name == "TextureWrap2" && cnt >= 2)
					{
						int map = ConvertMappingMode(prop.value);
						mat->AddProperty(&map,1,AI_MATKEY_MAPPINGMODE_U_DIFFUSE(1));
						mat->AddProperty(&map,1,AI_MATKEY_MAPPINGMODE_V_DIFFUSE(1));	
					}
					else if (prop.name == "TextureWrap3" && cnt >= 3)
					{
						int map = ConvertMappingMode(prop.value);
						mat->AddProperty(&map,1,AI_MATKEY_MAPPINGMODE_U_DIFFUSE(2));
						mat->AddProperty(&map,1,AI_MATKEY_MAPPINGMODE_V_DIFFUSE(2));
					}
					else if (prop.name == "TextureWrap4" && cnt >= 4)
					{
						int map = ConvertMappingMode(prop.value);
						mat->AddProperty(&map,1,AI_MATKEY_MAPPINGMODE_U_DIFFUSE(3));
						mat->AddProperty(&map,1,AI_MATKEY_MAPPINGMODE_V_DIFFUSE(3));
					}
				}
			}
			break;
			case EXN_ELEMENT_END:

				/* Assume there are no further nested nodes in <material> elements
				 */

				return mat;

			default:

				// GCC complains here ...
				break;
		}
	}
	DefaultLogger::get()->error("IRRMESH: Unexpected end of file. Material is not complete");
	return mat;
}

// ------------------------------------------------------------------------------------------------
// Imports the given file into the given scene structure. 
void IRRMeshImporter::InternReadFile( const std::string& pFile, 
	aiScene* pScene, IOSystem* pIOHandler)
{
	boost::scoped_ptr<IOStream> file( pIOHandler->Open( pFile));

	// Check whether we can read from the file
	if( file.get() == NULL)
		throw new ImportErrorException( "Failed to open IRRMESH file " + pFile + "");

	// Construct the irrXML parser
	CIrrXML_IOStreamReader st(file.get());
	reader = createIrrXMLReader((IFileReadCallBack*) &st);

	// final data
	std::vector<aiMaterial*> materials;
	std::vector<aiMesh*>     meshes;
	materials.reserve (5);
	meshes.reserve    (5);

	// temporary data - current mesh buffer
	aiMaterial* curMat	= NULL;
	aiMesh* curMesh		= NULL;
	unsigned int curMatFlags;

	std::vector<aiVector3D> curVertices,curNormals,curTangents,curBitangents;
	std::vector<aiColor4D>  curColors;
	std::vector<aiVector3D> curUVs,curUV2s;

	// some temporary variables
	int textMeaning = 0;
	int vertexFormat = 0; // 0 = normal; 1 = 2 tcoords, 2 = tangents
	bool useColors = false;

	// Parse the XML file
	while (reader->read())
	{
		switch (reader->getNodeType())
		{
		case EXN_ELEMENT:
			
			if (!ASSIMP_stricmp(reader->getNodeName(),"buffer") && (curMat || curMesh))
			{
				// end of previous buffer. A material and a mesh should be there
				if ( !curMat || !curMesh)
				{
					DefaultLogger::get()->error("IRRMESH: A buffer must contain a mesh and a material");
					delete curMat;
					delete curMesh;
				}
				else
				{
					materials.push_back(curMat); 
					meshes.push_back(curMesh);  
				}
				curMat  = NULL;
				curMesh = NULL;

				curVertices.clear();
				curColors.clear();
				curNormals.clear();
				curUV2s.clear();
				curUVs.clear();
			}
			

			if (!ASSIMP_stricmp(reader->getNodeName(),"material"))
			{
				if (curMat)
				{
					DefaultLogger::get()->warn("IRRMESH: Only one material description per buffer, please");
					delete curMat;
				}
				curMat = ParseMaterial(curMatFlags);
			}
			/* no else here! */ if (!ASSIMP_stricmp(reader->getNodeName(),"vertices"))
			{
				int num = reader->getAttributeValueAsInt("vertexCount");
				curVertices.reserve (num);
				curNormals.reserve  (num);
				curColors.reserve   (num);
				curUVs.reserve      (num);

				// Determine the file format
				const char* t = reader->getAttributeValueSafe("type");
				if (!ASSIMP_stricmp("2tcoords", t))
				{
					curUV2s.reserve (num);
					vertexFormat = 1;
				}
				else if (!ASSIMP_stricmp("tangents", t))
				{
					curTangents.reserve (num);
					curBitangents.reserve (num);
					vertexFormat = 2;
				}
				else if (ASSIMP_stricmp("standard", t))
				{
					DefaultLogger::get()->warn("IRRMESH: Unknown vertex format");
				}
				else vertexFormat = 0;
				textMeaning = 1;
			}
			else if (!ASSIMP_stricmp(reader->getNodeName(),"indices"))
			{
				if (curVertices.empty())
					throw new ImportErrorException("IRRMESH: indices must come after vertices");

				textMeaning = 2;

				// start a new mesh
				curMesh = new aiMesh();

				// allocate storage for all faces
				curMesh->mNumVertices = reader->getAttributeValueAsInt("indexCount");
				if (curMesh->mNumVertices % 3)
				{
					DefaultLogger::get()->warn("IRRMESH: Number if indices isn't divisible by 3");
				}

				curMesh->mNumFaces = curMesh->mNumVertices / 3;
				curMesh->mFaces = new aiFace[curMesh->mNumFaces];

				// setup some members
				curMesh->mMaterialIndex = (unsigned int)materials.size();
				curMesh->mPrimitiveTypes = aiPrimitiveType_TRIANGLE;

				// allocate storage for all vertices
				curMesh->mVertices = new aiVector3D[curMesh->mNumVertices];

				if (curNormals.size() == curVertices.size())
				{
					curMesh->mNormals = new aiVector3D[curMesh->mNumVertices];
				}
				if (curTangents.size() == curVertices.size())
				{
					curMesh->mTangents = new aiVector3D[curMesh->mNumVertices];
				}
				if (curBitangents.size() == curVertices.size())
				{
					curMesh->mBitangents = new aiVector3D[curMesh->mNumVertices];
				}
				if (curColors.size() == curVertices.size() && useColors)
				{
					curMesh->mColors[0] = new aiColor4D[curMesh->mNumVertices];
				}
				if (curUVs.size() == curVertices.size())
				{
					curMesh->mTextureCoords[0] = new aiVector3D[curMesh->mNumVertices];
				}
				if (curUV2s.size() == curVertices.size())
				{
					curMesh->mTextureCoords[1] = new aiVector3D[curMesh->mNumVertices];
				}
			}
			break;

		case EXN_TEXT:
			{
			const char* sz = reader->getNodeData();
			if (textMeaning == 1)
			{
				textMeaning = 0;

				// read vertices
				do
				{
					SkipSpacesAndLineEnd(&sz);
					aiVector3D temp;aiColor4D c;

					// Read the vertex position
					sz = fast_atof_move(sz,(float&)temp.x);
					SkipSpaces(&sz);

					sz = fast_atof_move(sz,(float&)temp.z);
					SkipSpaces(&sz);

					sz = fast_atof_move(sz,(float&)temp.y);
					SkipSpaces(&sz);
					temp.y *= -1.0f;
					curVertices.push_back(temp);

					// Read the vertex normals
					sz = fast_atof_move(sz,(float&)temp.x);
					SkipSpaces(&sz);

					sz = fast_atof_move(sz,(float&)temp.z);
					SkipSpaces(&sz);

					sz = fast_atof_move(sz,(float&)temp.y);
					SkipSpaces(&sz);
					temp.y *= -1.0f;
					curNormals.push_back(temp);

					// read the vertex colors
					uint32_t clr = strtol16(sz,&sz);	
					ColorFromARGBPacked(clr,c);

					if (!curColors.empty() && c != *(curColors.end()-1))
						useColors = true;

					curColors.push_back(c);
					SkipSpaces(&sz);


					// read the first UV coordinate set
					sz = fast_atof_move(sz,(float&)temp.x);
					SkipSpaces(&sz);

					sz = fast_atof_move(sz,(float&)temp.y);
					SkipSpaces(&sz);
					temp.z = 0.f;
					temp.y = 1.f - temp.y;  // DX to OGL
					curUVs.push_back(temp);

					// read the (optional) second UV coordinate set
					if (vertexFormat == 1)
					{
						sz = fast_atof_move(sz,(float&)temp.x);
						SkipSpaces(&sz);

						sz = fast_atof_move(sz,(float&)temp.y);
						temp.y = 1.f - temp.y; // DX to OGL
						curUV2s.push_back(temp);
					}
					// read optional tangent and bitangent vectors
					if (vertexFormat == 2)
					{
						// tangents
						sz = fast_atof_move(sz,(float&)temp.x);
						SkipSpaces(&sz);

						sz = fast_atof_move(sz,(float&)temp.z);
						SkipSpaces(&sz);

						sz = fast_atof_move(sz,(float&)temp.y);
						SkipSpaces(&sz);
						temp.y *= -1.0f;
						curTangents.push_back(temp);

						// bitangents
						sz = fast_atof_move(sz,(float&)temp.x);
						SkipSpaces(&sz);

						sz = fast_atof_move(sz,(float&)temp.z);
						SkipSpaces(&sz);

						sz = fast_atof_move(sz,(float&)temp.y);
						SkipSpaces(&sz);
						temp.y *= -1.0f;
						curBitangents.push_back(temp);
					}
				}

				/* IMPORTANT: We assume that each vertex is specified in one
				   line. So we can skip the rest of the line - unknown vertex
				   elements are ignored.
				 */

				while (SkipLine(&sz));
			}
			else if (textMeaning == 2)
			{
				textMeaning = 0;

				// read indices
				aiFace* curFace = curMesh->mFaces;
				aiFace* const faceEnd = curMesh->mFaces  + curMesh->mNumFaces;

				aiVector3D* pcV  = curMesh->mVertices;
				aiVector3D* pcN  = curMesh->mNormals;
				aiVector3D* pcT  = curMesh->mTangents;
				aiVector3D* pcB  = curMesh->mBitangents;
				aiColor4D* pcC0  = curMesh->mColors[0];
				aiVector3D* pcT0 = curMesh->mTextureCoords[0];
				aiVector3D* pcT1 = curMesh->mTextureCoords[1];

				unsigned int curIdx = 0;
				unsigned int total = 0;
				while(SkipSpacesAndLineEnd(&sz))
				{
					if (curFace >= faceEnd)
					{
						DefaultLogger::get()->error("IRRMESH: Too many indices");
						break;
					}
					if (!curIdx)
					{
						curFace->mNumIndices = 3;
						curFace->mIndices = new unsigned int[3];
					}

					unsigned int idx = strtol10(sz,&sz);
					if (idx >= curVertices.size())
					{
						DefaultLogger::get()->error("IRRMESH: Index out of range");
						idx = 0;
					}

					curFace->mIndices[curIdx] = total++;

					*pcV++ = curVertices[idx];
					if (pcN)*pcN++ = curNormals[idx];
					if (pcT)*pcT++ = curTangents[idx];
					if (pcB)*pcB++ = curBitangents[idx];
					if (pcC0)*pcC0++ = curColors[idx];
					if (pcT0)*pcT0++ = curUVs[idx];
					if (pcT1)*pcT1++ = curUV2s[idx];

					if (++curIdx == 3)
					{
						++curFace;
						curIdx = 0;
					}
				}

				if (curFace != faceEnd)
					DefaultLogger::get()->error("IRRMESH: Not enough indices");

				// Finish processing the mesh - do some small material workarounds
				if (curMatFlags == AI_IRRMESH_MAT_trans_vertex_alpha && !useColors)
				{
					// Take the opacity value of the current material
					// from the common vertex color alpha
					MaterialHelper* mat = (MaterialHelper*)curMat;
					mat->AddProperty(&curColors[0].a,1,AI_MATKEY_OPACITY);
				}

				/* TODO: Add lightmapping support here */
			}}
			break;

			default:

				// GCC complains here ...
				break;

		};
	}

	// end of the last buffer. A material and a mesh should be there
	if (curMat || curMesh)
	{
		if ( !curMat || !curMesh)
		{
			DefaultLogger::get()->error("IRRMESH: A buffer must contain a mesh and a material");
			delete curMat;
			delete curMesh;
		}
		else
		{
			materials.push_back(curMat); 
			meshes.push_back(curMesh);  
		}
	}

	// now generate the output scene
	pScene->mNumMeshes = (unsigned int)meshes.size();
	pScene->mMeshes = new aiMesh*[pScene->mNumMeshes];
	::memcpy(pScene->mMeshes,&meshes[0],sizeof(void*)*pScene->mNumMeshes);

	pScene->mNumMaterials = (unsigned int)materials.size();
	pScene->mMaterials = new aiMaterial*[pScene->mNumMaterials];
	::memcpy(pScene->mMaterials,&materials[0],sizeof(void*)*pScene->mNumMaterials);

	pScene->mRootNode = new aiNode();
	pScene->mRootNode->mName.Set("<IRRMesh>");
	pScene->mRootNode->mNumMeshes = pScene->mNumMeshes;
	pScene->mRootNode->mMeshes = new unsigned int[pScene->mNumMeshes];

	for (unsigned int i = 0; i < pScene->mNumMeshes;++i)
		pScene->mRootNode->mMeshes[i] = i;

	delete reader;
	AI_DEBUG_INVALIDATE_PTR(reader);
}