/*
--------------------------------------------------------------------------------
This source file is part of SkyX.
Visit http://www.paradise-studios.net/products/skyx/

Copyright (C) 2009-2011 Xavier Verguín González <xavyiy@gmail.com>

This program is free software; you can redistribute it and/or modify it under
the terms of the GNU Lesser General Public License as published by the Free Software
Foundation; either version 2 of the License, or (at your option) any later
version.

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 the GNU Lesser General Public License for more details.

You should have received a copy of the GNU Lesser General Public License along with
this program; if not, write to the Free Software Foundation, Inc., 59 Temple
Place - Suite 330, Boston, MA 02111-1307, USA, or go to
http://www.gnu.org/copyleft/lesser.txt.
--------------------------------------------------------------------------------
*/

#include "VClouds/GeometryManager.h"

#include "VClouds/VClouds.h"

namespace SkyX { namespace VClouds
{

	GeometryManager::GeometryManager(VClouds* vc,
		    const Ogre::Vector2& Height, const float& Radius,
		    const Ogre::Radian& Alpha, const Ogre::Radian& Beta, 
            const int& NumberOfBlocks, const int& Na, const int& Nb, const int& Nc)
		: mVClouds(vc)
		, mCreated(false)
		, mHeight(Height)
		, mRadius(Radius)
		, mAlpha(Alpha)
		, mBeta(Beta)
		, mPhi(Ogre::Math::TWO_PI / NumberOfBlocks)
		, mNumberOfBlocks(NumberOfBlocks)
		, mNa(Na) , mNb(Nb) , mNc (Nc)
		, mA(0), mB(0), mC(0)
		, mWorldOffset(Ogre::Vector2(0,0))
	{
	}

	GeometryManager::~GeometryManager()
	{
		remove();
	}

	void GeometryManager::create()
	{
		remove();

		mSceneNode = mVClouds->getSceneManager()->getRootSceneNode()->createChildSceneNode();
		_createGeometry();

		mCreated = true;
	}

	void GeometryManager::remove()
	{
		if (!mCreated)
		{
			return;
		}

		mSceneNode->detachAllObjects();
		mSceneNode->getParentSceneNode()->removeAndDestroyChild(mSceneNode->getName());
		mSceneNode = 0;

		for (int k = 0; k < mNumberOfBlocks; k++)
		{
			delete mGeometryBlocks.at(k);
			mGeometryBlocks.at(k) = 0;
		}

		mGeometryBlocks.clear();

		mCreated = false;
	}

	void GeometryManager::update(const Ogre::Real& timeSinceLastFrame)
	{
		if (!mCreated)
		{
			return;
		}

		mWorldOffset += mVClouds->getWindDirectionV2() * mVClouds->getWindSpeed() * timeSinceLastFrame;
	}

	void GeometryManager::updateGeometry(Ogre::Camera* c, const Ogre::Real& timeSinceLastCameraFrame)
	{
		if (!mCreated)
		{
			return;
		}

		mSceneNode->setPosition(mVClouds->getCamera()->getDerivedPosition().x, mHeight.x, mVClouds->getCamera()->getDerivedPosition().z);
		mSceneNode->_update(false, false);

		_updateGeometry(c, timeSinceLastCameraFrame);
	}

	void GeometryManager::_createGeometry()
	{
		mA = mHeight.y / Ogre::Math::Cos(Ogre::Math::PI/2-mBeta.valueRadians());
		mB = mHeight.y / Ogre::Math::Cos(Ogre::Math::PI/2-mAlpha.valueRadians());
	    mC = mRadius;

		for (int k = 0; k < mNumberOfBlocks; k++)
		{
			mGeometryBlocks.push_back(new GeometryBlock(mVClouds, mHeight.y, mAlpha, mBeta, mRadius, mPhi, mNa, mNb, mNc, mA, mB, mC, k));
			mGeometryBlocks.at(k)->create();
			// Each geometry block must be in a different scene node, See: GeometryBlock::isInFrustum(Ogre::Camera *c)
			Ogre::SceneNode *sn = mSceneNode->createChildSceneNode();
			sn->attachObject(mGeometryBlocks.at(k)->getEntity());
		}
	}

	void GeometryManager::_updateGeometry(Ogre::Camera* c, const Ogre::Real& timeSinceLastFrame)
	{
		// Look for current camera data
		std::vector<VClouds::CameraData>& camerasData = mVClouds->_getCamerasData();
		std::vector<VClouds::CameraData>::iterator currentCameraDataIt;

		for (currentCameraDataIt = camerasData.begin(); currentCameraDataIt != camerasData.end(); currentCameraDataIt++)
		{
			if ((*currentCameraDataIt).camera == c)
			{
				break;
			}
		}

		std::vector<VClouds::CameraData>::reference currentCameraData = (*currentCameraDataIt);

		// Calculate wind offset
		Ogre::Vector2 CameraDirection = Ogre::Vector2(c->getDerivedDirection().x, c->getDerivedDirection().z);
		float offset = - CameraDirection.dotProduct(mVClouds->getWindDirectionV2()) * mVClouds->getWindSpeed() * timeSinceLastFrame;

		// Calculate camera offset
		Ogre::Vector2 CameraOffset = Ogre::Vector2(c->getDerivedPosition().x - currentCameraData.lastPosition.x, c->getDerivedPosition().z - currentCameraData.lastPosition.z);
		offset -= CameraOffset.dotProduct(CameraDirection);

		// Update camera data
		currentCameraData.cameraOffset += CameraOffset;
		currentCameraData.lastPosition = c->getDerivedPosition();

		// Update geometry displacement
		currentCameraData.geometryDisplacement += Ogre::Vector3(offset);

		if (currentCameraData.geometryDisplacement.z < 0 || currentCameraData.geometryDisplacement.z > (mC-mB)/mNc)
		{
			currentCameraData.geometryDisplacement.z -= ((mC-mB)/mNc)*Ogre::Math::IFloor((currentCameraData.geometryDisplacement.z)/((mC-mB)/mNc));
		}

		if (currentCameraData.geometryDisplacement.y < 0 || currentCameraData.geometryDisplacement.y > (mB-mA)/mNb)
		{
			currentCameraData.geometryDisplacement.y -= ((mB-mA)/mNb)*Ogre::Math::IFloor((currentCameraData.geometryDisplacement.y)/((mB-mA)/mNb));
		}

		if (currentCameraData.geometryDisplacement.x < 0 || currentCameraData.geometryDisplacement.x > mA/mNa)
		{
			currentCameraData.geometryDisplacement.x -= (mA/mNa)*Ogre::Math::IFloor((currentCameraData.geometryDisplacement.x)/(mA/mNa));
		}

		for (int k = 0; k < mNumberOfBlocks; k++)
		{
			mGeometryBlocks.at(k)->setWorldOffset(mWorldOffset + currentCameraData.cameraOffset);
			mGeometryBlocks.at(k)->updateGeometry(c, currentCameraData.geometryDisplacement);
		}
	}
}}