//========================================================================
// TransformComponent.cpp - Component for managing transforms on actors
//
// Part of the GameCode4 Application
//
// GameCode4 is the sample application that encapsulates much of the source code
// discussed in "Game Coding Complete - 4th Edition" by Mike McShaffry and David
// "Rez" Graham, published by Charles River Media. 
// ISBN-10: 1133776574 | ISBN-13: 978-1133776574
//
// If this source code has found it's way to you, and you think it has helped you
// in any way, do the authors a favor and buy a new copy of the book - there are 
// detailed explanations in it that compliment this code well. Buy a copy at Amazon.com
// by clicking here: 
//    http://www.amazon.com/gp/product/1133776574/ref=olp_product_details?ie=UTF8&me=&seller=
//
// There's a companion web site at http://www.mcshaffry.com/GameCode/
// 
// The source code is managed and maintained through Google Code: 
//    http://code.google.com/p/gamecode4/
//
// (c) Copyright 2012 Michael L. McShaffry and David Graham
//
// This program is free software; you can redistribute it and/or
// modify it under the terms of the GNU Lesser GPL v3
// as published by the Free Software Foundation.
//
// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See 
// http://www.gnu.org/licenses/lgpl-3.0.txt for more details.
//
// You should have received a copy of the GNU Lesser GPL v3
// along with this program; if not, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.
//
//========================================================================

#include "../Unix/GameCodeStd.h"
#include "TransformComponent.h"
#include "../Graphics3D/Geometry.h"
#include "../Utilities/String.h"

#include <glm/gtx/string_cast.hpp>


const char* TransformComponent::g_Name = "TransformComponent";

bool TransformComponent::VInit(TiXmlElement* pData)
{
	GCC_ASSERT(pData);

	// [mrmike] - this was changed post-press - because changes to the TransformComponents can come in partial definitions,
	//            such as from the editor, its better to grab the current values rather than clear them out.

	// glm::vec3 yawPitchRoll = m_transform.GetYawPitchRoll();
	// yawPitchRoll.x = glm::degrees(yawPitchRoll.x);
	// yawPitchRoll.y = glm::degrees(yawPitchRoll.y);
	// yawPitchRoll.z = glm::degrees(yawPitchRoll.z);
	glm::vec3 yawPitchRoll;
	glm::vec3 position = geometry::GetPosition(m_transform);

	TiXmlElement* pPositionElement = pData->FirstChildElement("Position");
	if (pPositionElement)
	{
		double x = 0.0;
		double y = 0.0;
		double z = 0.0;
		pPositionElement->Attribute("x", &x);
		pPositionElement->Attribute("y", &y);
		pPositionElement->Attribute("z", &z);
		position = glm::vec3(x, y, z);
	}

	TiXmlElement* pOrientationElement = pData->FirstChildElement("YawPitchRoll");
	if (pOrientationElement)
	{
		double yaw = 0.0;
		double pitch = 0.0;
		double roll = 0.0;
		pOrientationElement->Attribute("x", &yaw);
		pOrientationElement->Attribute("y", &pitch);
		pOrientationElement->Attribute("z", &roll);
		yawPitchRoll = glm::vec3(yaw, pitch, roll);
	}

	glm::mat4 translation = geometry::BuildTranslation(position);
	glm::mat4 rotation = geometry::BuildYawPitchRoll(
		glm::radians(yawPitchRoll.x),
		glm::radians(yawPitchRoll.y),
		glm::radians(yawPitchRoll.z)
	);

	m_transform = rotation * translation;
	
	return true;
}

TiXmlElement* TransformComponent::VGenerateXml(void)
{
	TiXmlElement* pBaseElement = GCC_NEW TiXmlElement(VGetName());

	// initial transform -> position
	TiXmlElement *pPosition = GCC_NEW TiXmlElement("Position");
	glm::vec3 pos(geometry::GetPosition(m_transform));
	pPosition->SetAttribute("x", ToStr(pos.x).c_str());
	pPosition->SetAttribute("y", ToStr(pos.y).c_str());
	pPosition->SetAttribute("z", ToStr(pos.z).c_str());

	// initial transform -> LookAt
	TiXmlElement* pDirection = GCC_NEW TiXmlElement("YawPitchRoll");
	glm::vec3 orient(geometry::GetYawPitchRoll(m_transform));
	orient.x = glm::degrees(orient.x);
	orient.y = glm::degrees(orient.y);
	orient.z = glm::degrees(orient.z);
	pDirection->SetAttribute("x", ToStr(orient.x).c_str());
	pDirection->SetAttribute("y", ToStr(orient.y).c_str());
	pDirection->SetAttribute("z", ToStr(orient.z).c_str());
	pBaseElement->LinkEndChild(pDirection);

	return pBaseElement;
}