/// \file AMFImporter.cpp
/// \brief AMF-format files importer for Assimp: main algorithm implementation.
/// \date 2016
/// \author smal.root@gmail.com

#ifndef ASSIMP_BUILD_NO_AMF_IMPORTER

// Header files, Assimp.
#include "AMFImporter.hpp"
#include "AMFImporter_Macro.hpp"

#include "fast_atof.h"
#include "DefaultIOSystem.h"

// Header files, stdlib.
#include <memory>
#include <string>

namespace Assimp
{

/// \var aiImporterDesc AMFImporter::Description
/// Conastant which hold importer description
const aiImporterDesc AMFImporter::Description = {
	"Additive manufacturing file format(AMF) Importer",
	"smalcom",
	"",
	"See documentation in source code. Chapter: Limitations.",
	aiImporterFlags_SupportTextFlavour | aiImporterFlags_LimitedSupport | aiImporterFlags_Experimental,
	0,
	0,
	0,
	0,
	"amf"
};

void AMFImporter::Clear()
{
	mNodeElement_Cur = nullptr;
	mUnit.clear();
	mMaterial_Converted.clear();
	mTexture_Converted.clear();
	// Delete all elements
	if(mNodeElement_List.size())
	{
		for(CAMFImporter_NodeElement* ne: mNodeElement_List) { delete ne; }

		mNodeElement_List.clear();
	}
}

AMFImporter::~AMFImporter()
{
	if(mReader != nullptr) delete mReader;
	// Clear() is accounting if data already is deleted. So, just check again if all data is deleted.
	Clear();
}

/*********************************************************************************************************************************************/
/************************************************************ Functions: find set ************************************************************/
/*********************************************************************************************************************************************/

bool AMFImporter::Find_NodeElement(const std::string& pID, const CAMFImporter_NodeElement::EType pType, CAMFImporter_NodeElement** pNodeElement) const
{
	for(CAMFImporter_NodeElement* ne: mNodeElement_List)
	{
		if((ne->ID == pID) && (ne->Type == pType))
		{
			if(pNodeElement != nullptr) *pNodeElement = ne;

			return true;
		}
	}// for(CAMFImporter_NodeElement* ne: mNodeElement_List)

	return false;
}

bool AMFImporter::Find_ConvertedNode(const std::string& pID, std::list<aiNode*>& pNodeList, aiNode** pNode) const
{
aiString node_name(pID.c_str());

	for(aiNode* node: pNodeList)
	{
		if(node->mName == node_name)
		{
			if(pNode != nullptr) *pNode = node;

			return true;
		}
	}// for(aiNode* node: pNodeList)

	return false;
}

bool AMFImporter::Find_ConvertedMaterial(const std::string& pID, const SPP_Material** pConvertedMaterial) const
{
	for(const SPP_Material& mat: mMaterial_Converted)
	{
		if(mat.ID == pID)
		{
			if(pConvertedMaterial != nullptr) *pConvertedMaterial = &mat;

			return true;
		}
	}// for(const SPP_Material& mat: mMaterial_Converted)

	return false;
}

/*********************************************************************************************************************************************/
/************************************************************ Functions: throw set ***********************************************************/
/*********************************************************************************************************************************************/

void AMFImporter::Throw_CloseNotFound(const std::string& pNode)
{
	throw DeadlyImportError("Close tag for node <" + pNode + "> not found. Seems file is corrupt.");
}

void AMFImporter::Throw_IncorrectAttr(const std::string& pAttrName)
{
	throw DeadlyImportError("Node <" + std::string(mReader->getNodeName()) + "> has incorrect attribute \"" + pAttrName + "\".");
}

void AMFImporter::Throw_IncorrectAttrValue(const std::string& pAttrName)
{
	throw DeadlyImportError("Attribute \"" + pAttrName + "\" in node <" + std::string(mReader->getNodeName()) + "> has incorrect value.");
}

void AMFImporter::Throw_MoreThanOnceDefined(const std::string& pNodeType, const std::string& pDescription)
{
	throw DeadlyImportError("\"" + pNodeType + "\" node can be used only once in " + mReader->getNodeName() + ". Description: " + pDescription);
}

void AMFImporter::Throw_ID_NotFound(const std::string& pID) const
{
	throw DeadlyImportError("Not found node with name \"" + pID + "\".");
}

/*********************************************************************************************************************************************/
/************************************************************* Functions: XML set ************************************************************/
/*********************************************************************************************************************************************/

void AMFImporter::XML_CheckNode_MustHaveChildren()
{
	if(mReader->isEmptyElement()) throw DeadlyImportError(std::string("Node <") + mReader->getNodeName() + "> must have children.");
}

void AMFImporter::XML_CheckNode_SkipUnsupported(const std::string& pParentNodeName)
{
const size_t Uns_Skip_Len = 3;
const char* Uns_Skip[Uns_Skip_Len] = { "composite", "edge", "normal" };

static bool skipped_before[Uns_Skip_Len] = { false, false, false };

std::string nn(mReader->getNodeName());
bool found = false;
bool close_found = false;
size_t sk_idx;

	for(sk_idx = 0; sk_idx < Uns_Skip_Len; sk_idx++)
	{
		if(nn != Uns_Skip[sk_idx]) continue;

		found = true;
		if(mReader->isEmptyElement())
		{
			close_found = true;

			goto casu_cres;
		}

		while(mReader->read())
		{
			if((mReader->getNodeType() == irr::io::EXN_ELEMENT_END) && (nn == mReader->getNodeName()))
			{
				close_found = true;

				goto casu_cres;
			}
		}
	}// for(sk_idx = 0; sk_idx < Uns_Skip_Len; sk_idx++)

casu_cres:

	if(!found) throw DeadlyImportError("Unknown node \"" + nn + "\" in " + pParentNodeName + ".");
	if(!close_found) Throw_CloseNotFound(nn);

	if(!skipped_before[sk_idx])
	{
		skipped_before[sk_idx] = true;
		LogWarning("Skipping node \"" + nn + "\" in " + pParentNodeName + ".");
	}
}

bool AMFImporter::XML_SearchNode(const std::string& pNodeName)
{
	while(mReader->read())
	{
		if((mReader->getNodeType() == irr::io::EXN_ELEMENT) && XML_CheckNode_NameEqual(pNodeName)) return true;
	}

	return false;
}

bool AMFImporter::XML_ReadNode_GetAttrVal_AsBool(const int pAttrIdx)
{
std::string val(mReader->getAttributeValue(pAttrIdx));

	if((val == "false") || (val == "0"))
		return false;
	else if((val == "true") || (val == "1"))
		return true;
	else
		throw DeadlyImportError("Bool attribute value can contain \"false\"/\"0\" or \"true\"/\"1\" not the \"" + val + "\"");
}

float AMFImporter::XML_ReadNode_GetAttrVal_AsFloat(const int pAttrIdx)
{
std::string val;
float tvalf;

	ParseHelper_FixTruncatedFloatString(mReader->getAttributeValue(pAttrIdx), val);
	fast_atoreal_move(val.c_str(), tvalf, false);

	return tvalf;
}

uint32_t AMFImporter::XML_ReadNode_GetAttrVal_AsU32(const int pAttrIdx)
{
	return strtoul10(mReader->getAttributeValue(pAttrIdx));
}

float AMFImporter::XML_ReadNode_GetVal_AsFloat()
{
std::string val;
float tvalf;

	if(!mReader->read()) throw DeadlyImportError("XML_ReadNode_GetVal_AsFloat. No data, seems file is corrupt.");
	if(mReader->getNodeType() != irr::io::EXN_TEXT) throw DeadlyImportError("XML_ReadNode_GetVal_AsFloat. Invalid type of XML element, seems file is corrupt.");

	ParseHelper_FixTruncatedFloatString(mReader->getNodeData(), val);
	fast_atoreal_move(val.c_str(), tvalf, false);

	return tvalf;
}

uint32_t AMFImporter::XML_ReadNode_GetVal_AsU32()
{
	if(!mReader->read()) throw DeadlyImportError("XML_ReadNode_GetVal_AsU32. No data, seems file is corrupt.");
	if(mReader->getNodeType() != irr::io::EXN_TEXT) throw DeadlyImportError("XML_ReadNode_GetVal_AsU32. Invalid type of XML element, seems file is corrupt.");

	return strtoul10(mReader->getNodeData());
}

void AMFImporter::XML_ReadNode_GetVal_AsString(std::string& pValue)
{
	if(!mReader->read()) throw DeadlyImportError("XML_ReadNode_GetVal_AsString. No data, seems file is corrupt.");
	if(mReader->getNodeType() != irr::io::EXN_TEXT)
		throw DeadlyImportError("XML_ReadNode_GetVal_AsString. Invalid type of XML element, seems file is corrupt.");

	pValue = mReader->getNodeData();
}

/*********************************************************************************************************************************************/
/************************************************************ Functions: parse set ***********************************************************/
/*********************************************************************************************************************************************/

void AMFImporter::ParseHelper_Node_Enter(CAMFImporter_NodeElement* pNode)
{
	mNodeElement_Cur->Child.push_back(pNode);// add new element to current element child list.
	mNodeElement_Cur = pNode;// switch current element to new one.
}

void AMFImporter::ParseHelper_Node_Exit()
{
	// check if we can walk up.
	if(mNodeElement_Cur != nullptr) mNodeElement_Cur = mNodeElement_Cur->Parent;
}

void AMFImporter::ParseHelper_FixTruncatedFloatString(const char* pInStr, std::string& pOutString)
{
size_t instr_len;

	pOutString.clear();
	instr_len = strlen(pInStr);
	if(!instr_len) return;

	pOutString.reserve(instr_len * 3 / 2);
	// check and correct floats in format ".x". Must be "x.y".
	if(pInStr[0] == '.') pOutString.push_back('0');

	pOutString.push_back(pInStr[0]);
	for(size_t ci = 1; ci < instr_len; ci++)
	{
		if((pInStr[ci] == '.') && ((pInStr[ci - 1] == ' ') || (pInStr[ci - 1] == '-') || (pInStr[ci - 1] == '+') || (pInStr[ci - 1] == '\t')))
		{
			pOutString.push_back('0');
			pOutString.push_back('.');
		}
		else
		{
			pOutString.push_back(pInStr[ci]);
		}
	}
}

static bool ParseHelper_Decode_Base64_IsBase64(const char pChar)
{
	return (isalnum(pChar) || (pChar == '+') || (pChar == '/'));
}

void AMFImporter::ParseHelper_Decode_Base64(const std::string& pInputBase64, std::vector<uint8_t>& pOutputData) const
{
// With help from
// RenИ Nyffenegger http://www.adp-gmbh.ch/cpp/common/base64.html
const std::string base64_chars = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";

uint8_t tidx = 0;
uint8_t arr4[4], arr3[3];

	// check input data
	if(pInputBase64.size() % 4) throw DeadlyImportError("Base64-encoded data must have size multiply of four.");
	// prepare output place
	pOutputData.clear();
	pOutputData.reserve(pInputBase64.size() / 4 * 3);

	for(size_t in_len = pInputBase64.size(), in_idx = 0; (in_len > 0) && (pInputBase64[in_idx] != '='); in_len--)
	{
		if(ParseHelper_Decode_Base64_IsBase64(pInputBase64[in_idx]))
		{
			arr4[tidx++] = pInputBase64[in_idx++];
			if(tidx == 4)
			{
				for(tidx = 0; tidx < 4; tidx++) arr4[tidx] = (uint8_t)base64_chars.find(arr4[tidx]);

				arr3[0] = (arr4[0] << 2) + ((arr4[1] & 0x30) >> 4);
				arr3[1] = ((arr4[1] & 0x0F) << 4) + ((arr4[2] & 0x3C) >> 2);
				arr3[2] = ((arr4[2] & 0x03) << 6) + arr4[3];
				for(tidx = 0; tidx < 3; tidx++) pOutputData.push_back(arr3[tidx]);

				tidx = 0;
			}// if(tidx == 4)
		}// if(ParseHelper_Decode_Base64_IsBase64(pInputBase64[in_idx]))
		else
		{
			in_idx++;
		}// if(ParseHelper_Decode_Base64_IsBase64(pInputBase64[in_idx])) else
	}

	if(tidx)
	{
		for(uint8_t i = tidx; i < 4; i++) arr4[i] = 0;
		for(uint8_t i = 0; i < 4; i++) arr4[i] = (uint8_t)(base64_chars.find(arr4[i]));

		arr3[0] = (arr4[0] << 2) + ((arr4[1] & 0x30) >> 4);
		arr3[1] = ((arr4[1] & 0x0F) << 4) + ((arr4[2] & 0x3C) >> 2);
		arr3[2] = ((arr4[2] & 0x03) << 6) + arr4[3];
		for(uint8_t i = 0; i < (tidx - 1); i++) pOutputData.push_back(arr3[i]);
	}
}

void AMFImporter::ParseFile(const std::string& pFile, IOSystem* pIOHandler)
{
irr::io::IrrXMLReader* OldReader = mReader;// store current XMLreader.
std::unique_ptr<IOStream> file(pIOHandler->Open(pFile, "rb"));

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

	// generate a XML reader for it
	std::unique_ptr<CIrrXML_IOStreamReader> mIOWrapper(new CIrrXML_IOStreamReader(file.get()));
	mReader = irr::io::createIrrXMLReader(mIOWrapper.get());
	if(!mReader) throw DeadlyImportError("Failed to create XML reader for file" + pFile + ".");
	//
	// start reading
	// search for root tag <amf>
	if(XML_SearchNode("amf"))
		ParseNode_Root();
	else
		throw DeadlyImportError("Root node \"amf\" not found.");

	delete mReader;
	// restore old XMLreader
	mReader = OldReader;
}

// <amf
// unit="" - The units to be used. May be "inch", "millimeter", "meter", "feet", or "micron".
// version="" - Version of file format.
// >
// </amf>
// Root XML element.
// Multi elements - No.
void AMFImporter::ParseNode_Root()
{
std::string unit, version;
CAMFImporter_NodeElement* ne;

	// Read attributes for node <amf>.
	MACRO_ATTRREAD_LOOPBEG;
		MACRO_ATTRREAD_CHECK_RET("unit", unit, mReader->getAttributeValue);
		MACRO_ATTRREAD_CHECK_RET("version", version, mReader->getAttributeValue);
	MACRO_ATTRREAD_LOOPEND_WSKIP;

	// Check attributes
	if(!mUnit.empty())
	{
		if((mUnit != "inch") && (mUnit != "millimeter") && (mUnit != "meter") && (mUnit != "feet") && (mUnit != "micron")) Throw_IncorrectAttrValue("unit");
	}

	// create root node element.
	ne = new CAMFImporter_NodeElement_Root(nullptr);
	mNodeElement_Cur = ne;// set first "current" element
	// and assign attribute's values
	((CAMFImporter_NodeElement_Root*)ne)->Unit = unit;
	((CAMFImporter_NodeElement_Root*)ne)->Version = version;

	// Check for child nodes
	if(!mReader->isEmptyElement())
	{
		MACRO_NODECHECK_LOOPBEGIN("amf");
			if(XML_CheckNode_NameEqual("object")) { ParseNode_Object(); continue; }
			if(XML_CheckNode_NameEqual("material")) { ParseNode_Material(); continue; }
			if(XML_CheckNode_NameEqual("texture")) { ParseNode_Texture(); continue; }
			if(XML_CheckNode_NameEqual("constellation")) { ParseNode_Constellation(); continue; }
			if(XML_CheckNode_NameEqual("metadata")) { ParseNode_Metadata(); continue; }
		MACRO_NODECHECK_LOOPEND("amf");
		mNodeElement_Cur = ne;// force restore "current" element
	}// if(!mReader->isEmptyElement())

	mNodeElement_List.push_back(ne);// add to node element list because its a new object in graph.
}

// <constellation
// id="" - The Object ID of the new constellation being defined.
// >
// </constellation>
// A collection of objects or constellations with specific relative locations.
// Multi elements - Yes.
// Parent element - <amf>.
void AMFImporter::ParseNode_Constellation()
{
std::string id;
CAMFImporter_NodeElement* ne;

	// Read attributes for node <constellation>.
	MACRO_ATTRREAD_LOOPBEG;
		MACRO_ATTRREAD_CHECK_RET("id", id, mReader->getAttributeValue);
	MACRO_ATTRREAD_LOOPEND;

	// create and if needed - define new grouping object.
	ne = new CAMFImporter_NodeElement_Constellation(mNodeElement_Cur);

	CAMFImporter_NodeElement_Constellation& als = *((CAMFImporter_NodeElement_Constellation*)ne);// alias for convenience

	if(!id.empty()) als.ID = id;
	// Check for child nodes
	if(!mReader->isEmptyElement())
	{
		ParseHelper_Node_Enter(ne);
		MACRO_NODECHECK_LOOPBEGIN("constellation");
			if(XML_CheckNode_NameEqual("instance")) { ParseNode_Instance(); continue; }
			if(XML_CheckNode_NameEqual("metadata")) { ParseNode_Metadata(); continue; }
		MACRO_NODECHECK_LOOPEND("constellation");
		ParseHelper_Node_Exit();
	}// if(!mReader->isEmptyElement())
	else
	{
		mNodeElement_Cur->Child.push_back(ne);// Add element to child list of current element
	}// if(!mReader->isEmptyElement()) else

	mNodeElement_List.push_back(ne);// and to node element list because its a new object in graph.
}

// <instance
// objectid="" - The Object ID of the new constellation being defined.
// >
// </instance>
// A collection of objects or constellations with specific relative locations.
// Multi elements - Yes.
// Parent element - <amf>.
void AMFImporter::ParseNode_Instance()
{
std::string objectid;
CAMFImporter_NodeElement* ne;

	// Read attributes for node <constellation>.
	MACRO_ATTRREAD_LOOPBEG;
		MACRO_ATTRREAD_CHECK_RET("objectid", objectid, mReader->getAttributeValue);
	MACRO_ATTRREAD_LOOPEND;

	// used object id must be defined, check that.
	if(objectid.empty()) throw DeadlyImportError("\"objectid\" in <instance> must be defined.");
	// create and define new grouping object.
	ne = new CAMFImporter_NodeElement_Instance(mNodeElement_Cur);

	CAMFImporter_NodeElement_Instance& als = *((CAMFImporter_NodeElement_Instance*)ne);// alias for convenience

	als.ObjectID = objectid;
	// Check for child nodes
	if(!mReader->isEmptyElement())
	{
		bool read_flag[6] = { false, false, false, false, false, false };

		als.Delta.Set(0, 0, 0);
		als.Rotation.Set(0, 0, 0);
		ParseHelper_Node_Enter(ne);
		MACRO_NODECHECK_LOOPBEGIN("instance");
			MACRO_NODECHECK_READCOMP_F("deltax", read_flag[0], als.Delta.x);
			MACRO_NODECHECK_READCOMP_F("deltay", read_flag[1], als.Delta.y);
			MACRO_NODECHECK_READCOMP_F("deltaz", read_flag[2], als.Delta.z);
			MACRO_NODECHECK_READCOMP_F("rx", read_flag[3], als.Rotation.x);
			MACRO_NODECHECK_READCOMP_F("ry", read_flag[4], als.Rotation.y);
			MACRO_NODECHECK_READCOMP_F("rz", read_flag[5], als.Rotation.z);
		MACRO_NODECHECK_LOOPEND("instance");
		ParseHelper_Node_Exit();
		// also convert degrees to radians.
		als.Rotation.x = AI_MATH_PI_F * als.Rotation.x / 180.0f;
		als.Rotation.y = AI_MATH_PI_F * als.Rotation.y / 180.0f;
		als.Rotation.z = AI_MATH_PI_F * als.Rotation.z / 180.0f;
	}// if(!mReader->isEmptyElement())
	else
	{
		mNodeElement_Cur->Child.push_back(ne);// Add element to child list of current element
	}// if(!mReader->isEmptyElement()) else

	mNodeElement_List.push_back(ne);// and to node element list because its a new object in graph.
}

// <object
// id="" - A unique ObjectID for the new object being defined.
// >
// </object>
// An object definition.
// Multi elements - Yes.
// Parent element - <amf>.
void AMFImporter::ParseNode_Object()
{
std::string id;
CAMFImporter_NodeElement* ne;

	// Read attributes for node <object>.
	MACRO_ATTRREAD_LOOPBEG;
		MACRO_ATTRREAD_CHECK_RET("id", id, mReader->getAttributeValue);
	MACRO_ATTRREAD_LOOPEND;

	// create and if needed - define new geometry object.
	ne = new CAMFImporter_NodeElement_Object(mNodeElement_Cur);

	CAMFImporter_NodeElement_Object& als = *((CAMFImporter_NodeElement_Object*)ne);// alias for convenience

	if(!id.empty()) als.ID = id;
	// Check for child nodes
	if(!mReader->isEmptyElement())
	{
		bool col_read = false;

		ParseHelper_Node_Enter(ne);
		MACRO_NODECHECK_LOOPBEGIN("object");
			if(XML_CheckNode_NameEqual("color"))
			{
				// Check if color already defined for object.
				if(col_read) Throw_MoreThanOnceDefined("color", "Only one color can be defined for <object>.");
				// read data and set flag about it
				ParseNode_Color();
				col_read = true;

				continue;
			}

			if(XML_CheckNode_NameEqual("mesh")) { ParseNode_Mesh(); continue; }
			if(XML_CheckNode_NameEqual("metadata")) { ParseNode_Metadata(); continue; }
		MACRO_NODECHECK_LOOPEND("object");
		ParseHelper_Node_Exit();
	}// if(!mReader->isEmptyElement())
	else
	{
		mNodeElement_Cur->Child.push_back(ne);// Add element to child list of current element
	}// if(!mReader->isEmptyElement()) else

	mNodeElement_List.push_back(ne);// and to node element list because its a new object in graph.
}

// <metadata
// type="" - The type of the attribute.
// >
// </metadata>
// Specify additional information about an entity.
// Multi elements - Yes.
// Parent element - <amf>, <object>, <volume>, <material>, <vertex>.
//
// Reserved types are:
// "Name" - The alphanumeric label of the entity, to be used by the interpreter if interacting with the user.
// "Description" - A description of the content of the entity
// "URL" - A link to an external resource relating to the entity
// "Author" - Specifies the name(s) of the author(s) of the entity
// "Company" - Specifying the company generating the entity
// "CAD" - specifies the name of the originating CAD software and version
// "Revision" - specifies the revision of the entity
// "Tolerance" - specifies the desired manufacturing tolerance of the entity in entity's unit system
// "Volume" - specifies the total volume of the entity, in the entity's unit system, to be used for verification (object and volume only)
void AMFImporter::ParseNode_Metadata()
{
std::string type, value;
CAMFImporter_NodeElement* ne;

	// read attribute
	MACRO_ATTRREAD_LOOPBEG;
		MACRO_ATTRREAD_CHECK_RET("type", type, mReader->getAttributeValue);
	MACRO_ATTRREAD_LOOPEND;
	// and value of node.
	value = mReader->getNodeData();
	// Create node element and assign read data.
	ne = new CAMFImporter_NodeElement_Metadata(mNodeElement_Cur);
	((CAMFImporter_NodeElement_Metadata*)ne)->Type = type;
	((CAMFImporter_NodeElement_Metadata*)ne)->Value = value;
	mNodeElement_Cur->Child.push_back(ne);// Add element to child list of current element
	mNodeElement_List.push_back(ne);// and to node element list because its a new object in graph.
}

/*********************************************************************************************************************************************/
/******************************************************** Functions: BaseImporter set ********************************************************/
/*********************************************************************************************************************************************/

bool AMFImporter::CanRead(const std::string& pFile, IOSystem* pIOHandler, bool pCheckSig) const
{
const std::string extension = GetExtension(pFile);

	if(extension == "amf") return true;

	if(!extension.length() || pCheckSig)
	{
		const char* tokens[] = { "<?xml", "<amf" };

		return SearchFileHeaderForToken(pIOHandler, pFile, tokens, 2);
	}

	return false;
}

void AMFImporter::GetExtensionList(std::set<std::string>& pExtensionList)
{
	pExtensionList.insert("amf");
}

const aiImporterDesc* AMFImporter::GetInfo () const
{
	return &Description;
}

void AMFImporter::InternReadFile(const std::string& pFile, aiScene* pScene, IOSystem* pIOHandler)
{
	Clear();// delete old graph.
	ParseFile(pFile, pIOHandler);
	Postprocess_BuildScene(pScene);
	// scene graph is ready, exit.
}

}// namespace Assimp

#endif // !ASSIMP_BUILD_NO_AMF_IMPORTER