#include "modelclass.h"


ModelClass::ModelClass()
{
	m_vertexBuffer = 0;
	m_indexBuffer = 0;
	m_Textures = 0;
	m_model = 0;
}


ModelClass::ModelClass(const ModelClass& other)
{
}


ModelClass::~ModelClass()
{
}

bool ModelClass::Initialize(ID3D11Device* device, ID3D11DeviceContext* deviceContext, char* modelFilename, vector<string> filename)
{
	Logger::Get().Log("Initializing model class", __FILE__, __LINE__, Logger::LogLevel::Initialize);

	bool result;

	// Load in the model data.
	result = LoadModel(modelFilename);
	if (!result)
	{
		Logger::Get().Log("Failed to load model data", __FILE__, __LINE__, Logger::LogLevel::Error);
		return false;
	}

	// Calculate the tangent and binormal vectors for the model.
	CalculateModelVectors();

	// Initialize the vertex and index buffers.
	result = InitializeBuffers(device);
	if (!result)
	{
		Logger::Get().Log("Failed to initialize buffers", __FILE__, __LINE__, Logger::LogLevel::Error);
		return false;
	}
	// Load the textures for this model.
	result = LoadTextures(device, deviceContext, filename);
	if (!result)
	{
		Logger::Get().Log("Failed to load textures", __FILE__, __LINE__, Logger::LogLevel::Error);
		return false;
	}

	Logger::Get().Log("Model class initialized", __FILE__, __LINE__, Logger::LogLevel::Initialize);

	return true;
}


void ModelClass::Shutdown()
{
	// Release the model textures.
	ReleaseTextures();

	// Shutdown the vertex and index buffers.
	ShutdownBuffers();

	// Release the model data.
	ReleaseModel();

	return;
}


void ModelClass::Render(ID3D11DeviceContext* deviceContext)
{
	// Put the vertex and index buffers on the graphics pipeline to prepare them for drawing.
	RenderBuffers(deviceContext);

	return;
}


int ModelClass::GetIndexCount()
{
	return m_indexCount;
}

ID3D11ShaderResourceView* ModelClass::GetTexture(int index)
{
	return m_Textures[index].GetTexture();
}


bool ModelClass::InitializeBuffers(ID3D11Device* device)
{
	Logger::Get().Log("Initializing buffers", __FILE__, __LINE__, Logger::LogLevel::Initialize);

	VertexType* vertices;
	unsigned long* indices;
	D3D11_BUFFER_DESC vertexBufferDesc, indexBufferDesc;
	D3D11_SUBRESOURCE_DATA vertexData, indexData;
	HRESULT result;
	int i;

	// Create the vertex array.
	vertices = new VertexType[m_vertexCount];

	// Create the index array.
	indices = new unsigned long[m_indexCount];

	// Load the vertex array and index array with data.
	for (i = 0; i < m_vertexCount; i++)
	{
		vertices[i].position = XMFLOAT3(m_model[i].x, m_model[i].y, m_model[i].z);
		vertices[i].texture = XMFLOAT2(m_model[i].tu, m_model[i].tv);
		vertices[i].normal = XMFLOAT3(m_model[i].nx, m_model[i].ny, m_model[i].nz);
		vertices[i].tangent = XMFLOAT3(m_model[i].tx, m_model[i].ty, m_model[i].tz);
		vertices[i].binormal = XMFLOAT3(m_model[i].bx, m_model[i].by, m_model[i].bz);

		indices[i] = i;
	}

	// Set up the description of the static vertex buffer.
	vertexBufferDesc.Usage = D3D11_USAGE_DEFAULT;
	vertexBufferDesc.ByteWidth = sizeof(VertexType) * m_vertexCount;
	vertexBufferDesc.BindFlags = D3D11_BIND_VERTEX_BUFFER;
	vertexBufferDesc.CPUAccessFlags = 0;
	vertexBufferDesc.MiscFlags = 0;
	vertexBufferDesc.StructureByteStride = 0;

	// Give the subresource structure a pointer to the vertex data.
	vertexData.pSysMem = vertices;
	vertexData.SysMemPitch = 0;
	vertexData.SysMemSlicePitch = 0;

	// Now create the vertex buffer.
	result = device->CreateBuffer(&vertexBufferDesc, &vertexData, &m_vertexBuffer);
	if (FAILED(result))
	{
		Logger::Get().Log("Failed to create vertex buffer", __FILE__, __LINE__, Logger::LogLevel::Error);
		return false;
	}

	// Set up the description of the static index buffer.
	indexBufferDesc.Usage = D3D11_USAGE_DEFAULT;
	indexBufferDesc.ByteWidth = sizeof(unsigned long) * m_indexCount;
	indexBufferDesc.BindFlags = D3D11_BIND_INDEX_BUFFER;
	indexBufferDesc.CPUAccessFlags = 0;
	indexBufferDesc.MiscFlags = 0;
	indexBufferDesc.StructureByteStride = 0;

	// Give the subresource structure a pointer to the index data.
	indexData.pSysMem = indices;
	indexData.SysMemPitch = 0;
	indexData.SysMemSlicePitch = 0;

	// Create the index buffer.
	result = device->CreateBuffer(&indexBufferDesc, &indexData, &m_indexBuffer);
	if (FAILED(result))
	{
		Logger::Get().Log("Failed to create index buffer", __FILE__, __LINE__, Logger::LogLevel::Error);
		return false;
	}

	// Release the arrays now that the vertex and index buffers have been created and loaded.
	delete[] vertices;
	vertices = 0;

	delete[] indices;
	indices = 0;

	Logger::Get().Log("Buffers initialized", __FILE__, __LINE__, Logger::LogLevel::Initialize);

	return true;
}


void ModelClass::ShutdownBuffers()
{
	Logger::Get().Log("Shutting down buffers", __FILE__, __LINE__, Logger::LogLevel::Shutdown);
	// Release the index buffer.
	if (m_indexBuffer)
	{
		m_indexBuffer->Release();
		m_indexBuffer = 0;
	}

	// Release the vertex buffer.
	if (m_vertexBuffer)
	{
		m_vertexBuffer->Release();
		m_vertexBuffer = 0;
	}

	Logger::Get().Log("Buffers shut down", __FILE__, __LINE__, Logger::LogLevel::Shutdown);

	return;
}


void ModelClass::RenderBuffers(ID3D11DeviceContext* deviceContext)
{
	unsigned int stride;
	unsigned int offset;


	// Set vertex buffer stride and offset.
	stride = sizeof(VertexType);
	offset = 0;

	// Set the vertex buffer to active in the input assembler so it can be rendered.
	deviceContext->IASetVertexBuffers(0, 1, &m_vertexBuffer, &stride, &offset);

	// Set the index buffer to active in the input assembler so it can be rendered.
	deviceContext->IASetIndexBuffer(m_indexBuffer, DXGI_FORMAT_R32_UINT, 0);

	// Set the type of primitive that should be rendered from this vertex buffer, in this case triangles.
	deviceContext->IASetPrimitiveTopology(D3D11_PRIMITIVE_TOPOLOGY_TRIANGLELIST);

	return;
}


bool ModelClass::LoadTextures(ID3D11Device* device, ID3D11DeviceContext* deviceContext, vector<string> textureFile)
{
	Logger::Get().Log("Loading textures", __FILE__, __LINE__);

	bool result;

	// Create and initialize the texture object array.
	m_Textures = new TextureClass[textureFile.size()];

	for (int i = 0; i < textureFile.size(); i++)
	{
		result = m_Textures[i].Initialize(device, deviceContext, textureFile[i]);
		if (!result)
		{
			Logger::Get().Log("Failed to initialize texture", __FILE__, __LINE__, Logger::LogLevel::Error);
			return false;
		}
	}

	Logger::Get().Log("Textures loaded", __FILE__, __LINE__);

	return true;
}

void ModelClass::ReleaseTextures()
{
	Logger::Get().Log("Releasing textures", __FILE__, __LINE__);

	// Release the texture object array.
	if (m_Textures)
	{
		m_Textures[0].Shutdown();
		m_Textures[1].Shutdown();
		m_Textures[2].Shutdown();
		m_Textures[3].Shutdown();
		m_Textures[4].Shutdown();
		m_Textures[5].Shutdown();

		delete[] m_Textures;
		m_Textures = 0;
	}

	Logger::Get().Log("Textures released", __FILE__, __LINE__);

	return;
}

bool ModelClass::LoadModel(char* filename)
{
	Logger::Get().Log("Loading model", __FILE__, __LINE__);

	ifstream fin;
	char input;
	int i;


	// Open the model file.
	fin.open(filename);

	// If it could not open the file then exit.
	if (fin.fail())
	{
		Logger::Get().Log("Failed to open model file", __FILE__, __LINE__, Logger::LogLevel::Error);
		return false;
	}

	// Read up to the value of vertex count.
	fin.get(input);
	while (input != ':')
	{
		fin.get(input);
	}

	// Read in the vertex count.
	fin >> m_vertexCount;

	// Set the number of indices to be the same as the vertex count.
	m_indexCount = m_vertexCount;

	// Create the model using the vertex count that was read in.
	m_model = new ModelType[m_vertexCount];

	// Read up to the beginning of the data.
	fin.get(input);
	while (input != ':')
	{
		fin.get(input);
	}
	fin.get(input);
	fin.get(input);

	// Read in the vertex data.
	for (i = 0; i < m_vertexCount; i++)
	{
		fin >> m_model[i].x >> m_model[i].y >> m_model[i].z;
		fin >> m_model[i].tu >> m_model[i].tv;
		fin >> m_model[i].nx >> m_model[i].ny >> m_model[i].nz;
	}

	// Close the model file.
	fin.close();

	Logger::Get().Log("Model loaded", __FILE__, __LINE__);

	return true;
}

void ModelClass::CalculateModelVectors()
{
	Logger::Get().Log("Calculating model vectors", __FILE__, __LINE__);

	int faceCount, i, index;
	TempVertexType vertex1, vertex2, vertex3;
	VectorType tangent, binormal;


	// Calculate the number of faces in the model.
	faceCount = m_vertexCount / 3;

	// Initialize the index to the model data.
	index = 0;

	// Go through all the faces and calculate the the tangent and binormal vectors.
	for (i = 0; i < faceCount; i++)
	{
		// Get the three vertices for this face from the model.
		vertex1.x = m_model[index].x;
		vertex1.y = m_model[index].y;
		vertex1.z = m_model[index].z;
		vertex1.tu = m_model[index].tu;
		vertex1.tv = m_model[index].tv;
		index++;

		vertex2.x = m_model[index].x;
		vertex2.y = m_model[index].y;
		vertex2.z = m_model[index].z;
		vertex2.tu = m_model[index].tu;
		vertex2.tv = m_model[index].tv;
		index++;

		vertex3.x = m_model[index].x;
		vertex3.y = m_model[index].y;
		vertex3.z = m_model[index].z;
		vertex3.tu = m_model[index].tu;
		vertex3.tv = m_model[index].tv;
		index++;

		// Calculate the tangent and binormal of that face.
		CalculateTangentBinormal(vertex1, vertex2, vertex3, tangent, binormal);

		// Store the tangent and binormal for this face back in the model structure.
		m_model[index - 1].tx = tangent.x;
		m_model[index - 1].ty = tangent.y;
		m_model[index - 1].tz = tangent.z;
		m_model[index - 1].bx = binormal.x;
		m_model[index - 1].by = binormal.y;
		m_model[index - 1].bz = binormal.z;

		m_model[index - 2].tx = tangent.x;
		m_model[index - 2].ty = tangent.y;
		m_model[index - 2].tz = tangent.z;
		m_model[index - 2].bx = binormal.x;
		m_model[index - 2].by = binormal.y;
		m_model[index - 2].bz = binormal.z;

		m_model[index - 3].tx = tangent.x;
		m_model[index - 3].ty = tangent.y;
		m_model[index - 3].tz = tangent.z;
		m_model[index - 3].bx = binormal.x;
		m_model[index - 3].by = binormal.y;
		m_model[index - 3].bz = binormal.z;
	}

	Logger::Get().Log("Model vectors calculated", __FILE__, __LINE__);

	return;
}

void ModelClass::CalculateTangentBinormal(TempVertexType vertex1, TempVertexType vertex2, TempVertexType vertex3, VectorType& tangent, VectorType& binormal)
{

	float vector1[3], vector2[3];
	float tuVector[2], tvVector[2];
	float den;
	float length;


	// Calculate the two vectors for this face.
	vector1[0] = vertex2.x - vertex1.x;
	vector1[1] = vertex2.y - vertex1.y;
	vector1[2] = vertex2.z - vertex1.z;

	vector2[0] = vertex3.x - vertex1.x;
	vector2[1] = vertex3.y - vertex1.y;
	vector2[2] = vertex3.z - vertex1.z;

	// Calculate the tu and tv texture space vectors.
	tuVector[0] = vertex2.tu - vertex1.tu;
	tvVector[0] = vertex2.tv - vertex1.tv;

	tuVector[1] = vertex3.tu - vertex1.tu;
	tvVector[1] = vertex3.tv - vertex1.tv;

	// Calculate the denominator of the tangent/binormal equation.
	den = 1.0f / (tuVector[0] * tvVector[1] - tuVector[1] * tvVector[0]);

	// Calculate the cross products and multiply by the coefficient to get the tangent and binormal.
	tangent.x = (tvVector[1] * vector1[0] - tvVector[0] * vector2[0]) * den;
	tangent.y = (tvVector[1] * vector1[1] - tvVector[0] * vector2[1]) * den;
	tangent.z = (tvVector[1] * vector1[2] - tvVector[0] * vector2[2]) * den;

	binormal.x = (tuVector[0] * vector2[0] - tuVector[1] * vector1[0]) * den;
	binormal.y = (tuVector[0] * vector2[1] - tuVector[1] * vector1[1]) * den;
	binormal.z = (tuVector[0] * vector2[2] - tuVector[1] * vector1[2]) * den;

	// Calculate the length of this normal.
	length = sqrt((tangent.x * tangent.x) + (tangent.y * tangent.y) + (tangent.z * tangent.z));

	// Normalize the normal and then store it
	tangent.x = tangent.x / length;
	tangent.y = tangent.y / length;
	tangent.z = tangent.z / length;

	// Calculate the length of this normal.
	length = sqrt((binormal.x * binormal.x) + (binormal.y * binormal.y) + (binormal.z * binormal.z));

	// Normalize the normal and then store it
	binormal.x = binormal.x / length;
	binormal.y = binormal.y / length;
	binormal.z = binormal.z / length;

	return;
}

void ModelClass::ReleaseModel()
{
	Logger::Get().Log("Releasing model", __FILE__, __LINE__);

	if (m_model)
	{
		delete[] m_model;
		m_model = 0;
	}

	Logger::Get().Log("Model released", __FILE__, __LINE__);

	return;
}

bool ModelClass::ChangeTexture(ID3D11Device* device, ID3D11DeviceContext* deviceContext, std::wstring filename, int index)
{
	bool result;

	// convert wstring to string
	std::string str(filename.begin(), filename.end());

	// Release the old texture object.
	m_Textures[index].Shutdown();

	// Initialize the new texture object.
	result = m_Textures[index].Initialize(device, deviceContext, str);
	if (!result)
	{
		Logger::Get().Log("Failed to initialize texture", __FILE__, __LINE__, Logger::LogLevel::Error);
		return false;
	}

	Logger::Get().Log("Texture changed", __FILE__, __LINE__);

	return true;
}