/*
---------------------------------------------------------------------------
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,
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*/

/** @file  B3DImporter.cpp
 *  @brief Implementation of the b3d importer class
 */

#include "AssimpPCH.h"
#ifndef ASSIMP_BUILD_NO_B3D_IMPORTER

// internal headers
#include "B3DImporter.h"
#include "TextureTransform.h"
#include "ConvertToLHProcess.h"

using namespace Assimp;
using namespace std;

//#define DEBUG_B3D

// ------------------------------------------------------------------------------------------------
bool B3DImporter::CanRead( const std::string& pFile, IOSystem* pIOHandler, bool checkSig) const{

	int pos=pFile.find_last_of( '.' );
	if( pos==string::npos ) return false;

	string ext=pFile.substr( pos+1 );
	if( ext.size()!=3 ) return false;

	return (ext[0]=='b' || ext[0]=='B') && (ext[1]=='3') && (ext[2]=='d' || ext[2]=='D');
}

// ------------------------------------------------------------------------------------------------
void B3DImporter::GetExtensionList( std::string& append ){
	append.append("*.b3d");
}

#ifdef DEBUG_B3D
	extern "C"{ void _stdcall AllocConsole(); }
#endif
// ------------------------------------------------------------------------------------------------
void B3DImporter::InternReadFile( const std::string& pFile, aiScene* pScene, IOSystem* pIOHandler){

#ifdef DEBUG_B3D
	AllocConsole();
	freopen( "conin$","r",stdin );
	freopen( "conout$","w",stdout );
	freopen( "conout$","w",stderr );
	cout<<"Hello world from the B3DImporter!"<<endl;
#endif

	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 B3D file " + pFile + ".");

	// check whether the .b3d file is large enough to contain
	// at least one chunk.
	size_t fileSize = file->FileSize();
	if( fileSize<8 ) throw new ImportErrorException( "B3D File is too small.");

	_pos=0;
	_buf.resize( fileSize );
	file->Read( &_buf[0],1,fileSize );
	_stack.clear();

	ReadBB3D( pScene );
}

// ------------------------------------------------------------------------------------------------
void B3DImporter::Oops(){
	throw new ImportErrorException( "B3D Importer - INTERNAL ERROR" );
}

// ------------------------------------------------------------------------------------------------
void B3DImporter::Fail( string str ){
#ifdef DEBUG_B3D
	cout<<"Error in B3D file data: "<<str<<endl;
#endif
	throw new ImportErrorException( "B3D Importer - error in B3D file data: "+str );
}

// ------------------------------------------------------------------------------------------------
int B3DImporter::ReadByte(){
	if( _pos<_buf.size() ) return _buf[_pos++];
	Fail( "EOF" );
}

// ------------------------------------------------------------------------------------------------
int B3DImporter::ReadInt(){
	if( _pos+4<=_buf.size() ){
		int n=*(int*)&_buf[_pos];
		_pos+=4;
		return n;
	}
	Fail( "EOF" );
}

// ------------------------------------------------------------------------------------------------
float B3DImporter::ReadFloat(){
	if( _pos+4<=_buf.size() ){
		float n=*(float*)&_buf[_pos];
		_pos+=4;
		return n;
	}
	Fail( "EOF" );
}

// ------------------------------------------------------------------------------------------------
aiVector2D B3DImporter::ReadVec2(){
	float x=ReadFloat();
	float y=ReadFloat();
	return aiVector2D( x,y );
}

// ------------------------------------------------------------------------------------------------
aiVector3D B3DImporter::ReadVec3(){
	float x=ReadFloat();
	float y=ReadFloat();
	float z=ReadFloat();
	return aiVector3D( x,y,z );
}

// ------------------------------------------------------------------------------------------------
aiQuaternion B3DImporter::ReadQuat(){
	float w=ReadFloat();
	float x=ReadFloat();
	float y=ReadFloat();
	float z=ReadFloat();
	return aiQuaternion( w,x,y,z );
}

// ------------------------------------------------------------------------------------------------
string B3DImporter::ReadString(){
	string str;
	while( _pos<_buf.size() ){
		char c=(char)ReadByte();
		if( !c ) return str;
		str+=c;
	}
	Fail( "EOF" );
}

// ------------------------------------------------------------------------------------------------
string B3DImporter::ReadChunk(){
	string tag;
	for( int i=0;i<4;++i ){
		tag+=char( ReadByte() );
	}
#ifdef DEBUG_B3D
//	cout<<"ReadChunk:"<<tag<<endl;
#endif
	unsigned sz=(unsigned)ReadInt();
	_stack.push_back( _pos+sz );
	return tag;
}

// ------------------------------------------------------------------------------------------------
void B3DImporter::ExitChunk(){
	_pos=_stack.back();
	_stack.pop_back();
}

// ------------------------------------------------------------------------------------------------
unsigned B3DImporter::ChunkSize(){
	return _stack.back()-_pos;
}
// ------------------------------------------------------------------------------------------------

template<class T>
T *B3DImporter::to_array( const vector<T> &v ){
	if( !v.size() ) return 0;
	T *p=new T[v.size()];
	for( int i=0;i<v.size();++i ){
		p[i]=v[i];
	}
	return p;
}

// ------------------------------------------------------------------------------------------------
void B3DImporter::ReadTEXS(){
	while( ChunkSize() ){
		string name=ReadString();
		int flags=ReadInt();
		int blend=ReadInt();
		aiVector2D pos=ReadVec2();
		aiVector2D scale=ReadVec2();
		float rot=ReadFloat();

		_textures.push_back( name );
	}
}

// ------------------------------------------------------------------------------------------------
void B3DImporter::ReadBRUS(){
	int n_texs=ReadInt();
	if( n_texs<0 || n_texs>8 ){
		Fail( "Bad texture count" );
	}
	while( ChunkSize() ){
		string name=ReadString();
		aiVector3D color=ReadVec3();
		float alpha=ReadFloat();
		float shiny=ReadFloat();
		int blend=ReadInt();
		int fx=ReadInt();

		MaterialHelper *mat=new MaterialHelper;
		_materials.push_back( mat );
		
		// Name
		aiString ainame( name );
		mat->AddProperty( &ainame,AI_MATKEY_NAME );
		
		// Diffuse color 
		mat->AddProperty( &color,1,AI_MATKEY_COLOR_DIFFUSE );

		// Opacity
		mat->AddProperty( &alpha,1,AI_MATKEY_OPACITY );

		// Specular color
		aiColor3D speccolor( shiny,shiny,shiny );
		mat->AddProperty( &speccolor,1,AI_MATKEY_COLOR_SPECULAR );
		
		// Specular power
		float specpow=shiny*128;
		mat->AddProperty( &specpow,1,AI_MATKEY_SHININESS );
		
		// Double sided
		if( fx & 0x10 ){
			int i=1; 
			mat->AddProperty( &i,1,AI_MATKEY_TWOSIDED );
		} 		

		//Textures
		for( int i=0;i<n_texs;++i ){
			int texid=ReadInt();
			if( texid<-1 || (texid>=0 && texid>=_textures.size()) ){
				Fail( "Bad texture id" );
			}
			if( i==0 && texid>=0 ){
				aiString texname( _textures[texid] );
				mat->AddProperty( &texname,AI_MATKEY_TEXTURE_DIFFUSE(0) );
			}
		}
	}
}

// ------------------------------------------------------------------------------------------------
void B3DImporter::ReadVRTS(){
	_vflags=ReadInt();
	_tcsets=ReadInt();
	_tcsize=ReadInt();
	if( _tcsets<0 || _tcsets>4 || _tcsize<0 || _tcsize>4 ){
		Fail( "Bad texcoord data" );
	}

	int sz=12+(_vflags&1?12:0)+(_vflags&2?16:0)+(_tcsets*_tcsize*4);
	int n_verts=ChunkSize()/sz;

	_vertices.clear();
	_vertices.resize( n_verts );

	for( int i=0;i<n_verts;++i ){
		Vertex &v=_vertices[i];

		memset( v.bones,0,sizeof(v.bones) );
		memset( v.weights,0,sizeof(v.weights) );

		v.vertex=ReadVec3();

		if( _vflags & 1 ) v.normal=ReadVec3();

		if( _vflags & 2 ) ReadQuat();	//skip v 4bytes...

		for( int i=0;i<_tcsets;++i ){
			float t[4]={0,0,0,0};
			for( int j=0;j<_tcsize;++j ){
				t[j]=ReadFloat();
			}
			t[1]=1-t[1];
			if( !i ) v.texcoords=aiVector3D( t[0],t[1],t[2] );
		}
	}
}

// ------------------------------------------------------------------------------------------------
void B3DImporter::ReadTRIS( int v0 ){
	int matid=ReadInt();
	if( matid==-1 ){
		matid=0;
	}else if( matid<0 || matid>=_materials.size() ){
#ifdef DEBUG_B3D
		cout<<"material id="<<matid<<endl;
#endif
		Fail( "Bad material id" );
	}

	int n_tris=ChunkSize()/12;

	aiMesh *mesh=new aiMesh;
	_meshes.push_back( mesh );

	mesh->mMaterialIndex=matid;
	mesh->mNumFaces=n_tris;
	mesh->mPrimitiveTypes=aiPrimitiveType_TRIANGLE;

	aiFace *face=mesh->mFaces=new aiFace[n_tris];

	for( int i=0;i<n_tris;++i ){
		int i0=ReadInt()+v0;
		int i1=ReadInt()+v0;
		int i2=ReadInt()+v0;
		if( i0<0 || i0>=_vertices.size() || i1<0 || i1>=_vertices.size() || i2<0 || i2>=_vertices.size() ){
#ifdef DEBUG_B3D
			cout<<"i0="<<i0<<", i1="<<i1<<", i2="<<i2<<endl;
#endif
			Fail( "Bad triangle index" );
		}
		face->mNumIndices=3;
		face->mIndices=new unsigned[3];
		face->mIndices[0]=i0;
		face->mIndices[1]=i1;
		face->mIndices[2]=i2;
		++face;
	}
}

// ------------------------------------------------------------------------------------------------
void B3DImporter::ReadMESH(){
	int matid=ReadInt();

	int v0=_vertices.size();

	while( ChunkSize() ){
		string t=ReadChunk();
		if( t=="VRTS" ){
			ReadVRTS();
		}else if( t=="TRIS" ){
			ReadTRIS( v0 );
		}
		ExitChunk();
	}
}

// ------------------------------------------------------------------------------------------------
void B3DImporter::ReadBONE( int id ){
	while( ChunkSize() ){
		int vertex=ReadInt();
		float weight=ReadFloat();
		if( vertex<0 || vertex>=_vertices.size() ){
			Fail( "Bad vertex index" );
		}

		Vertex &v=_vertices[vertex];
		int i;
		for( i=0;i<4;++i ){
			if( !v.weights[i] ){
				v.bones[i]=id;
				v.weights[i]=weight;
				break;
			}
		}
#ifdef DEBUG_B3D
		if( i==4 ){
			cout<<"Too many bone weights"<<endl;
		}
#endif
	}
}

// ------------------------------------------------------------------------------------------------
void B3DImporter::ReadKEYS( aiNodeAnim *nodeAnim ){
	vector<aiVectorKey> trans,scale;
	vector<aiQuatKey> rot;
	int flags=ReadInt();
	while( ChunkSize() ){
		int frame=ReadInt();
		if( flags & 1 ){
			trans.push_back( aiVectorKey( frame,ReadVec3() ) );
		}
		if( flags & 2 ){
			scale.push_back( aiVectorKey( frame,ReadVec3() ) );
		}
		if( flags & 4 ){
			rot.push_back( aiQuatKey( frame,ReadQuat() ) );
		}
	}

	if( flags & 1 ){
		nodeAnim->mNumPositionKeys=trans.size();
		nodeAnim->mPositionKeys=to_array( trans );
	}

	if( flags & 2 ){
		nodeAnim->mNumScalingKeys=scale.size();
		nodeAnim->mScalingKeys=to_array( scale );
	}

	if( flags & 4 ){
		nodeAnim->mNumRotationKeys=rot.size();
		nodeAnim->mRotationKeys=to_array( rot );
	}
}

// ------------------------------------------------------------------------------------------------
void B3DImporter::ReadANIM(){
	int flags=ReadInt();
	int frames=ReadInt();
	float fps=ReadFloat();

	aiAnimation *anim=new aiAnimation;
	_animations.push_back( anim );

	anim->mDuration=frames;
	anim->mTicksPerSecond=fps;
}

// ------------------------------------------------------------------------------------------------
aiNode *B3DImporter::ReadNODE( aiNode *parent ){

	string name=ReadString();
	aiVector3D t=ReadVec3();
	aiVector3D s=ReadVec3();
	aiQuaternion r=ReadQuat();

	aiMatrix4x4 trans,scale,rot;

	aiMatrix4x4::Translation( t,trans );
	aiMatrix4x4::Scaling( s,scale );
	rot=aiMatrix4x4( r.GetMatrix() );

	aiMatrix4x4 tform=trans * rot * scale;

	int nodeid=_nodes.size();

	aiNode *node=new aiNode( name );
	_nodes.push_back( node );

	node->mParent=parent;
	node->mTransformation=tform;

	aiNodeAnim *nodeAnim=0;
	vector<unsigned> meshes;
	vector<aiNode*> children;

	while( ChunkSize() ){
		string t=ReadChunk();
		if( t=="MESH" ){
			int n=_meshes.size();
			ReadMESH();
			for( int i=n;i<_meshes.size();++i ){
				meshes.push_back( i );
			}
		}else if( t=="BONE" ){
			ReadBONE( nodeid );
		}else if( t=="ANIM" ){
			ReadANIM();
		}else if( t=="KEYS" ){
			if( !nodeAnim ){
				nodeAnim=new aiNodeAnim;
				_nodeAnims.push_back( nodeAnim );
				nodeAnim->mNodeName=node->mName;
			}
			ReadKEYS( nodeAnim );
		}else if( t=="NODE" ){
			aiNode *child=ReadNODE( node );
			children.push_back( child );
		}
		ExitChunk();
	}

	node->mNumMeshes=meshes.size();
	node->mMeshes=to_array( meshes );

	node->mNumChildren=children.size();
	node->mChildren=to_array( children );

	return node;
}

// ------------------------------------------------------------------------------------------------
void B3DImporter::ReadBB3D( aiScene *scene ){

	_textures.clear();
	_materials.size();

	_vertices.clear();
	_meshes.clear();

	_nodes.clear();
	_nodeAnims.clear();
	_animations.clear();

	string t=ReadChunk();
	if( t=="BB3D" ){
		int version=ReadInt();
		while( ChunkSize() ){
			string t=ReadChunk();
			if( t=="TEXS" ){
				ReadTEXS();
			}else if( t=="BRUS" ){
				ReadBRUS();
			}else if( t=="NODE" ){
				ReadNODE( 0 );
			}
			ExitChunk();
		}
	}
	ExitChunk();

	if( !_nodes.size() ) Fail( "No nodes" );

	if( !_meshes.size() ) Fail( "No meshes" );

	//Fix nodes/meshes/bones
	for( int i=0;i<_nodes.size();++i ){
		aiNode *node=_nodes[i];

		for( int j=0;j<node->mNumMeshes;++j ){
			aiMesh *mesh=_meshes[node->mMeshes[j]];

			int n_tris=mesh->mNumFaces;
			int n_verts=mesh->mNumVertices=n_tris * 3;

			aiVector3D *mv=mesh->mVertices=new aiVector3D[ n_verts ],*mn=0,*mc=0;
			if( _vflags & 1 ) mn=mesh->mNormals=new aiVector3D[ n_verts ];
			if( _tcsets ) mc=mesh->mTextureCoords[0]=new aiVector3D[ n_verts ];

			aiFace *face=mesh->mFaces;

			vector< vector<aiVertexWeight> > vweights( _nodes.size() );

			for( int i=0;i<n_verts;i+=3 ){
				for( int j=0;j<3;++j ){
					Vertex &v=_vertices[face->mIndices[j]];

					*mv++=v.vertex;
					if( mn ) *mn++=v.normal;
					if( mc ) *mc++=v.texcoords;

					face->mIndices[j]=i+j;

					for( int k=0;k<4;++k ){
						if( !v.weights[k] ) break;

						int bone=v.bones[k];
						float weight=v.weights[k];

						vweights[bone].push_back( aiVertexWeight(i+j,weight) );
					}
				}
				++face;
			}

			vector<aiBone*> bones;
			for( int i=0;i<vweights.size();++i ){
				vector<aiVertexWeight> &weights=vweights[i];
				if( !weights.size() ) continue;

				aiBone *bone=new aiBone;
				bones.push_back( bone );

				aiNode *bnode=_nodes[i];

				bone->mName=bnode->mName;
				bone->mNumWeights=weights.size();
				bone->mWeights=to_array( weights );

				aiMatrix4x4 mat=bnode->mTransformation;
				while( bnode->mParent ){
					bnode=bnode->mParent;
					mat=bnode->mTransformation * mat;
				}
				bone->mOffsetMatrix=mat.Inverse();
			}
			mesh->mNumBones=bones.size();
			mesh->mBones=to_array( bones );
		}
	}

	//nodes
	scene->mRootNode=_nodes[0];

	//materials
	if( !_materials.size() ){
		_materials.push_back( new MaterialHelper );
	}
	scene->mNumMaterials=_materials.size();
	scene->mMaterials=to_array( _materials );
	
	//meshes
	scene->mNumMeshes=_meshes.size();
	scene->mMeshes=to_array( _meshes );

	//animations
	if( _animations.size()==1 && _nodeAnims.size() ){

		aiAnimation *anim=_animations.back();
		anim->mNumChannels=_nodeAnims.size();
		anim->mChannels=to_array( _nodeAnims );

		scene->mNumAnimations=_animations.size();
		scene->mAnimations=to_array( _animations );
	}

	// convert to RH
	MakeLeftHandedProcess makeleft;
	makeleft.Execute( scene );

	FlipWindingOrderProcess flip;
	flip.Execute( scene );
}

#endif // !! ASSIMP_BUILD_NO_B3D_IMPORTER