/*
---------------------------------------------------------------------------
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  UnrealLoader.cpp
 *  @brief Implementation of the UNREAL (*.3D) importer class
 *
 *  Sources:
 *    http://local.wasp.uwa.edu.au/~pbourke/dataformats/unreal/
 */



#ifndef ASSIMP_BUILD_NO_3D_IMPORTER

#include "UnrealLoader.h"
#include "StreamReader.h"
#include "ParsingUtils.h"
#include "fast_atof.h"
#include "ConvertToLHProcess.h"

#include <assimp/Importer.hpp>
#include <assimp/DefaultLogger.hpp>
#include <assimp/IOSystem.hpp>
#include <assimp/scene.h>

#include <boost/scoped_ptr.hpp>

using namespace Assimp;

static const aiImporterDesc desc = {
	"Unreal Mesh Importer",
	"",
	"",
	"",
	aiImporterFlags_SupportTextFlavour,
	0,
	0,
	0,
	0,
	"3d uc" 
};


// ------------------------------------------------------------------------------------------------
// Constructor to be privately used by Importer
UnrealImporter::UnrealImporter()
:	configFrameID	(0)
,	configHandleFlags (true)
{}

// ------------------------------------------------------------------------------------------------
// Destructor, private as well 
UnrealImporter::~UnrealImporter()
{}

// ------------------------------------------------------------------------------------------------
// Returns whether the class can handle the format of the given file. 
bool UnrealImporter::CanRead( const std::string& pFile, IOSystem* /*pIOHandler*/, bool /*checkSig*/) const
{
	return  SimpleExtensionCheck(pFile,"3d","uc");
}

// ------------------------------------------------------------------------------------------------
// Build a string of all file extensions supported
const aiImporterDesc* UnrealImporter::GetInfo () const
{
	return &desc;
}

// ------------------------------------------------------------------------------------------------
// Setup configuration properties for the loader
void UnrealImporter::SetupProperties(const Importer* pImp)
{
	// The 
	// AI_CONFIG_IMPORT_UNREAL_KEYFRAME option overrides the
	// AI_CONFIG_IMPORT_GLOBAL_KEYFRAME option.
	configFrameID = pImp->GetPropertyInteger(AI_CONFIG_IMPORT_UNREAL_KEYFRAME,-1);
	if(static_cast<unsigned int>(-1) == configFrameID)	{
		configFrameID = pImp->GetPropertyInteger(AI_CONFIG_IMPORT_GLOBAL_KEYFRAME,0);
	}

	// AI_CONFIG_IMPORT_UNREAL_HANDLE_FLAGS, default is true
	configHandleFlags = (0 != pImp->GetPropertyInteger(AI_CONFIG_IMPORT_UNREAL_HANDLE_FLAGS,1));
}

// ------------------------------------------------------------------------------------------------
// Imports the given file into the given scene structure. 
void UnrealImporter::InternReadFile( const std::string& pFile, 
	aiScene* pScene, IOSystem* pIOHandler)
{
	// For any of the 3 files being passed get the three correct paths
	// First of all, determine file extension
	std::string::size_type pos = pFile.find_last_of('.');
	std::string extension = GetExtension(pFile);

	std::string d_path,a_path,uc_path;
	if (extension == "3d")		{
		// jjjj_d.3d
		// jjjj_a.3d
		pos = pFile.find_last_of('_');
		if (std::string::npos == pos) {
			throw DeadlyImportError("UNREAL: Unexpected naming scheme");
		}
		extension = pFile.substr(0,pos);
	}
	else {
		extension = pFile.substr(0,pos);
	}

	// build proper paths
	d_path  = extension+"_d.3d";
	a_path  = extension+"_a.3d";
	uc_path = extension+".uc";

	DefaultLogger::get()->debug("UNREAL: data file is " + d_path);
	DefaultLogger::get()->debug("UNREAL: aniv file is " + a_path);
	DefaultLogger::get()->debug("UNREAL: uc file is "   + uc_path);

	// and open the files ... we can't live without them
	IOStream* p = pIOHandler->Open(d_path);
	if (!p)
		throw DeadlyImportError("UNREAL: Unable to open _d file");
	StreamReaderLE d_reader(pIOHandler->Open(d_path));

	const uint16_t numTris = d_reader.GetI2();
	const uint16_t numVert = d_reader.GetI2();
	d_reader.IncPtr(44);
	if (!numTris || numVert < 3)
		throw DeadlyImportError("UNREAL: Invalid number of vertices/triangles");

	// maximum texture index
	unsigned int maxTexIdx = 0;

	// collect triangles
	std::vector<Unreal::Triangle> triangles(numTris);
	for (std::vector<Unreal::Triangle>::iterator it = triangles.begin(), end = triangles.end();it != end; ++it)	{
		Unreal::Triangle& tri = *it;

		for (unsigned int i = 0; i < 3;++i)	{

			tri.mVertex[i] = d_reader.GetI2();
			if (tri.mVertex[i] >= numTris)	{
				DefaultLogger::get()->warn("UNREAL: vertex index out of range");
				tri.mVertex[i] = 0;
			}
		}
		tri.mType = d_reader.GetI1();

		// handle mesh flagss?
		if (configHandleFlags)
			tri.mType = Unreal::MF_NORMAL_OS;
		else {
			// ignore MOD and MASKED for the moment, treat them as two-sided
			if (tri.mType == Unreal::MF_NORMAL_MOD_TS || tri.mType == Unreal::MF_NORMAL_MASKED_TS)
				tri.mType = Unreal::MF_NORMAL_TS;
		}
		d_reader.IncPtr(1);

		for (unsigned int i = 0; i < 3;++i)
			for (unsigned int i2 = 0; i2 < 2;++i2)
				tri.mTex[i][i2] = d_reader.GetI1();

		tri.mTextureNum = d_reader.GetI1();
		maxTexIdx = std::max(maxTexIdx,(unsigned int)tri.mTextureNum);
		d_reader.IncPtr(1);
	}

	p = pIOHandler->Open(a_path);
	if (!p)
		throw DeadlyImportError("UNREAL: Unable to open _a file");
	StreamReaderLE a_reader(pIOHandler->Open(a_path));

	// read number of frames
	const uint32_t numFrames = a_reader.GetI2();
	if (configFrameID >= numFrames)
		throw DeadlyImportError("UNREAL: The requested frame does not exist");

	uint32_t st = a_reader.GetI2(); 
	if (st != numVert*4)
		throw DeadlyImportError("UNREAL: Unexpected aniv file length");

	// skip to our frame
	a_reader.IncPtr(configFrameID *numVert*4);

	// collect vertices
	std::vector<aiVector3D> vertices(numVert);
	for (std::vector<aiVector3D>::iterator it = vertices.begin(), end = vertices.end(); it != end; ++it)	{
		int32_t val = a_reader.GetI4();
		Unreal::DecompressVertex(*it,val);
	}

	// list of textures. 
	std::vector< std::pair<unsigned int, std::string> > textures; 

	// allocate the output scene
	aiNode* nd = pScene->mRootNode = new aiNode();
	nd->mName.Set("<UnrealRoot>");

	// we can live without the uc file if necessary
	boost::scoped_ptr<IOStream> pb (pIOHandler->Open(uc_path));
	if (pb.get())	{

		std::vector<char> _data;
		TextFileToBuffer(pb.get(),_data);
		const char* data = &_data[0];

		std::vector< std::pair< std::string,std::string > > tempTextures;

		// do a quick search in the UC file for some known, usually texture-related, tags
		for (;*data;++data)	{
			if (TokenMatchI(data,"#exec",5))	{
				SkipSpacesAndLineEnd(&data);

				// #exec TEXTURE IMPORT [...] NAME=jjjjj [...] FILE=jjjj.pcx [...] 
				if (TokenMatchI(data,"TEXTURE",7))	{
					SkipSpacesAndLineEnd(&data);

					if (TokenMatchI(data,"IMPORT",6))	{
						tempTextures.push_back(std::pair< std::string,std::string >());
						std::pair< std::string,std::string >& me = tempTextures.back();
						for (;!IsLineEnd(*data);++data)	{
							if (!::ASSIMP_strincmp(data,"NAME=",5))	{
								const char *d = data+=5;
								for (;!IsSpaceOrNewLine(*data);++data);
								me.first = std::string(d,(size_t)(data-d)); 
							}
							else if (!::ASSIMP_strincmp(data,"FILE=",5))	{
								const char *d = data+=5;
								for (;!IsSpaceOrNewLine(*data);++data);
								me.second = std::string(d,(size_t)(data-d)); 
							}
						}
						if (!me.first.length() || !me.second.length())
							tempTextures.pop_back();
					}
				}
				// #exec MESHMAP SETTEXTURE MESHMAP=box NUM=1 TEXTURE=Jtex1
				// #exec MESHMAP SCALE MESHMAP=box X=0.1 Y=0.1 Z=0.2
				else if (TokenMatchI(data,"MESHMAP",7)) {
					SkipSpacesAndLineEnd(&data);

					if (TokenMatchI(data,"SETTEXTURE",10)) {
					
						textures.push_back(std::pair<unsigned int, std::string>());
						std::pair<unsigned int, std::string>& me = textures.back();

						for (;!IsLineEnd(*data);++data)	{
							if (!::ASSIMP_strincmp(data,"NUM=",4))	{
								data += 4;
								me.first = strtoul10(data,&data);
							}
							else if (!::ASSIMP_strincmp(data,"TEXTURE=",8))	{
								data += 8;
								const char *d = data;
								for (;!IsSpaceOrNewLine(*data);++data);
								me.second = std::string(d,(size_t)(data-d)); 
					
								// try to find matching path names, doesn't care if we don't find them
								for (std::vector< std::pair< std::string,std::string > >::const_iterator it = tempTextures.begin();
									 it != tempTextures.end(); ++it)	{
									if ((*it).first == me.second)	{
										me.second = (*it).second;
										break;
									}
								}
							}	
						}
					}
					else if (TokenMatchI(data,"SCALE",5)) {

						for (;!IsLineEnd(*data);++data)	{
							if (data[0] == 'X' && data[1] == '=')	{
								data = fast_atoreal_move<float>(data+2,(float&)nd->mTransformation.a1);
							}
							else if (data[0] == 'Y' && data[1] == '=')	{
								data = fast_atoreal_move<float>(data+2,(float&)nd->mTransformation.b2);
							}
							else if (data[0] == 'Z' && data[1] == '=')	{
								data = fast_atoreal_move<float>(data+2,(float&)nd->mTransformation.c3);
							}
						}
					}
				}
			}
		}
	}
	else	{
		DefaultLogger::get()->error("Unable to open .uc file");
	}

	std::vector<Unreal::TempMat> materials;
	materials.reserve(textures.size()*2+5);

	// find out how many output meshes and materials we'll have and build material indices
	for (std::vector<Unreal::Triangle>::iterator it = triangles.begin(), end = triangles.end();it != end; ++it)	{
		Unreal::Triangle& tri = *it;
		Unreal::TempMat mat(tri);
		std::vector<Unreal::TempMat>::iterator nt = std::find(materials.begin(),materials.end(),mat);
		if (nt == materials.end()) {
			// add material
			tri.matIndex = materials.size();
			mat.numFaces = 1;
			materials.push_back(mat);

			++pScene->mNumMeshes;
		}
		else {
			tri.matIndex = static_cast<unsigned int>(nt-materials.begin());
			++nt->numFaces;
		}
	}

	if (!pScene->mNumMeshes) {
		throw DeadlyImportError("UNREAL: Unable to find valid mesh data");
	}

	// allocate meshes and bind them to the node graph
	pScene->mMeshes = new aiMesh*[pScene->mNumMeshes];
	pScene->mMaterials = new aiMaterial*[pScene->mNumMaterials = pScene->mNumMeshes];

	nd->mNumMeshes  = pScene->mNumMeshes;
	nd->mMeshes = new unsigned int[nd->mNumMeshes];
	for (unsigned int i = 0; i < pScene->mNumMeshes;++i) {
		aiMesh* m = pScene->mMeshes[i] =  new aiMesh();
		m->mPrimitiveTypes = aiPrimitiveType_TRIANGLE;

		const unsigned int num = materials[i].numFaces;
		m->mFaces            = new aiFace     [num];
		m->mVertices         = new aiVector3D [num*3];
		m->mTextureCoords[0] = new aiVector3D [num*3];

		nd->mMeshes[i] = i;

		// create materials, too
		aiMaterial* mat = new aiMaterial();
		pScene->mMaterials[i] = mat;

		// all white by default - texture rulez
		aiColor3D color(1.f,1.f,1.f);

		aiString s;
		::sprintf(s.data,"mat%i_tx%i_",i,materials[i].tex);

		// set the two-sided flag
		if (materials[i].type == Unreal::MF_NORMAL_TS) {
			const int twosided = 1;
			mat->AddProperty(&twosided,1,AI_MATKEY_TWOSIDED);
			::strcat(s.data,"ts_");
		}
		else ::strcat(s.data,"os_");

		// make TRANS faces 90% opaque that RemRedundantMaterials won't catch us
		if (materials[i].type == Unreal::MF_NORMAL_TRANS_TS)	{
			const float opac = 0.9f;
			mat->AddProperty(&opac,1,AI_MATKEY_OPACITY);
			::strcat(s.data,"tran_");
		}
		else ::strcat(s.data,"opaq_");

		// a special name for the weapon attachment point
		if (materials[i].type == Unreal::MF_WEAPON_PLACEHOLDER)	{
			s.length = ::sprintf(s.data,"$WeaponTag$");
			color = aiColor3D(0.f,0.f,0.f);
		}

		// set color and name
		mat->AddProperty(&color,1,AI_MATKEY_COLOR_DIFFUSE);
		s.length = ::strlen(s.data);
		mat->AddProperty(&s,AI_MATKEY_NAME);

		// set texture, if any
		const unsigned int tex = materials[i].tex;
		for (std::vector< std::pair< unsigned int, std::string > >::const_iterator it = textures.begin();it != textures.end();++it)	{
			if ((*it).first == tex)	{
				s.Set((*it).second);
				mat->AddProperty(&s,AI_MATKEY_TEXTURE_DIFFUSE(0));
				break;
			}
		}
	}

	// fill them.
	for (std::vector<Unreal::Triangle>::iterator it = triangles.begin(), end = triangles.end();it != end; ++it)	{
		Unreal::Triangle& tri = *it;
		Unreal::TempMat mat(tri);
		std::vector<Unreal::TempMat>::iterator nt = std::find(materials.begin(),materials.end(),mat);

		aiMesh* mesh = pScene->mMeshes[nt-materials.begin()];
		aiFace& f    = mesh->mFaces[mesh->mNumFaces++];
		f.mIndices   = new unsigned int[f.mNumIndices = 3];
		
		for (unsigned int i = 0; i < 3;++i,mesh->mNumVertices++) {
			f.mIndices[i] = mesh->mNumVertices;

			mesh->mVertices[mesh->mNumVertices] = vertices[ tri.mVertex[i] ];
			mesh->mTextureCoords[0][mesh->mNumVertices] = aiVector3D( tri.mTex[i][0] / 255.f, 1.f - tri.mTex[i][1] / 255.f, 0.f);
		}
	}

	// convert to RH
	MakeLeftHandedProcess hero;
	hero.Execute(pScene);

	FlipWindingOrderProcess flipper;
	flipper.Execute(pScene);
}

#endif // !! ASSIMP_BUILD_NO_3D_IMPORTER