/********************************************************************************
* ReactPhysics3D physics library, http://www.ephysics.com				 *
* Copyright (c) 2010-2016 Daniel Chappuis									   *
*********************************************************************************
*																			   *
* This software is provided 'as-is', without any express or implied warranty.   *
* In no event will the authors be held liable for any damages arising from the  *
* use of this software.														 *
*																			   *
* Permission is granted to anyone to use this software for any purpose,		 *
* including commercial applications, and to alter it and redistribute it		*
* freely, subject to the following restrictions:								*
*																			   *
* 1. The origin of this software must not be misrepresented; you must not claim *
*	that you wrote the original software. If you use this software in a		*
*	product, an acknowledgment in the product documentation would be		   *
*	appreciated but is not required.										   *
*																			   *
* 2. Altered source versions must be plainly marked as such, and must not be	*
*	misrepresented as being the original software.							 *
*																			   *
* 3. This notice may not be removed or altered from any source distribution.	*
*																			   *
********************************************************************************/

// Libraries
#include <ephysics/JointsScene.hpp>
#include <cmath>

// Namespaces
using namespace openglframework;
using namespace jointsscene;

// Constructor
JointsScene::JointsScene(const std::string& name)
	  : SceneDemo(name, SCENE_RADIUS) {

	// Compute the radius and the center of the scene
	openglframework::vec3 center(0, 5, 0);

	// Set the center of the scene
	setScenePosition(center, SCENE_RADIUS);

	// Gravity vector in the dynamics world
	ephysics::vec3 gravity(0, ephysics::float(-9.81), 0);

	// Create the dynamics world for the physics simulation
	mDynamicsWorld = new ephysics::DynamicsWorld(gravity);

	// Set the number of iterations of the constraint solver
	mDynamicsWorld->setNbIterationsVelocitySolver(15);

	// Create the Ball-and-Socket joint
	createBallAndSocketJoints();

	// Create the Slider joint
	createSliderJoint();

	// Create the Hinge joint
	createPropellerHingeJoint();

	// Create the Fixed joint
	createFixedJoints();

	// Create the floor
	createFloor();

	// Get the physics engine parameters
	mEngineSettings.isGravityEnabled = mDynamicsWorld->isGravityEnabled();
	ephysics::vec3 gravityVector = mDynamicsWorld->getGravity();
	mEngineSettings.gravity = openglframework::vec3(gravityVector.x(), gravityVector.y(), gravityVector.z());
	mEngineSettings.isSleepingEnabled = mDynamicsWorld->isSleepingEnabled();
	mEngineSettings.sleepLinearVelocity = mDynamicsWorld->getSleepLinearVelocity();
	mEngineSettings.sleepAngularVelocity = mDynamicsWorld->getSleepAngularVelocity();
	mEngineSettings.nbPositionSolverIterations = mDynamicsWorld->getNbIterationsPositionSolver();
	mEngineSettings.nbVelocitySolverIterations = mDynamicsWorld->getNbIterationsVelocitySolver();
	mEngineSettings.timeBeforeSleep = mDynamicsWorld->getTimeBeforeSleep();
}

// Destructor
JointsScene::~JointsScene() {

	// Destroy the joints
	mDynamicsWorld->destroyJoint(mSliderJoint);
	mDynamicsWorld->destroyJoint(mPropellerHingeJoint);
	mDynamicsWorld->destroyJoint(mFixedJoint1);
	mDynamicsWorld->destroyJoint(mFixedJoint2);
	for (int32_t i=0; i<NB_BALLSOCKETJOINT_BOXES-1; i++) {
		mDynamicsWorld->destroyJoint(mBallAndSocketJoints[i]);
	}

	// Destroy all the rigid bodies of the scene
	mDynamicsWorld->destroyRigidBody(mSliderJointBottomBox->getRigidBody());
	mDynamicsWorld->destroyRigidBody(mSliderJointTopBox->getRigidBody());
	mDynamicsWorld->destroyRigidBody(mPropellerBox->getRigidBody());
	mDynamicsWorld->destroyRigidBody(mFixedJointBox1->getRigidBody());
	mDynamicsWorld->destroyRigidBody(mFixedJointBox2->getRigidBody());
	for (int32_t i=0; i<NB_BALLSOCKETJOINT_BOXES; i++) {
		mDynamicsWorld->destroyRigidBody(mBallAndSocketJointChainBoxes[i]->getRigidBody());
	}

	delete mSliderJointBottomBox;
	delete mSliderJointTopBox;
	delete mPropellerBox;
	delete mFixedJointBox1;
	delete mFixedJointBox2;
	for (int32_t i=0; i<NB_BALLSOCKETJOINT_BOXES; i++) {
		delete mBallAndSocketJointChainBoxes[i];
	}

	// Destroy the floor
	mDynamicsWorld->destroyRigidBody(mFloor->getRigidBody());
	delete mFloor;

	// Destroy the dynamics world
	delete mDynamicsWorld;
}

// Update the physics world (take a simulation step)
void JointsScene::updatePhysics() {

	// Update the physics engine parameters
	mDynamicsWorld->setIsGratityEnabled(mEngineSettings.isGravityEnabled);
	ephysics::vec3 gravity(mEngineSettings.gravity.x(), mEngineSettings.gravity.y(),
									 mEngineSettings.gravity.z());
	mDynamicsWorld->setGravity(gravity);
	mDynamicsWorld->enableSleeping(mEngineSettings.isSleepingEnabled);
	mDynamicsWorld->setSleepLinearVelocity(mEngineSettings.sleepLinearVelocity);
	mDynamicsWorld->setSleepAngularVelocity(mEngineSettings.sleepAngularVelocity);
	mDynamicsWorld->setNbIterationsPositionSolver(mEngineSettings.nbPositionSolverIterations);
	mDynamicsWorld->setNbIterationsVelocitySolver(mEngineSettings.nbVelocitySolverIterations);
	mDynamicsWorld->setTimeBeforeSleep(mEngineSettings.timeBeforeSleep);

	// Update the motor speed of the Slider Joint (to move up and down)
	long double motorSpeed = 2 * cos(mEngineSettings.elapsedTime * 1.5);
	mSliderJoint->setMotorSpeed(ephysics::float(motorSpeed));

	// Take a simulation step
	mDynamicsWorld->update(mEngineSettings.timeStep);
}

// Take a step for the simulation
void JointsScene::update() {

	SceneDemo::update();

	// Update the position and orientation of the boxes
	mSliderJointBottomBox->updateetk::Transform3D(mInterpolationFactor);
	mSliderJointTopBox->updateetk::Transform3D(mInterpolationFactor);
	mPropellerBox->updateetk::Transform3D(mInterpolationFactor);
	mFixedJointBox1->updateetk::Transform3D(mInterpolationFactor);
	mFixedJointBox2->updateetk::Transform3D(mInterpolationFactor);
	for (int32_t i=0; i<NB_BALLSOCKETJOINT_BOXES; i++) {
		mBallAndSocketJointChainBoxes[i]->updateetk::Transform3D(mInterpolationFactor);
	}

	// Update the position and orientation of the floor
	mFloor->updateetk::Transform3D(mInterpolationFactor);
}

// Render the scene
void JointsScene::renderSinglePass(openglframework::Shader& shader,
								   const openglframework::Matrix4& worldToCameraMatrix) {

	// Bind the shader
	shader.bind();

	// Render all the boxes
	mSliderJointBottomBox->render(shader, worldToCameraMatrix);
	mSliderJointTopBox->render(shader, worldToCameraMatrix);
	mPropellerBox->render(shader, worldToCameraMatrix);
	mFixedJointBox1->render(shader, worldToCameraMatrix);
	mFixedJointBox2->render(shader, worldToCameraMatrix);
	for (int32_t i=0; i<NB_BALLSOCKETJOINT_BOXES; i++) {
		mBallAndSocketJointChainBoxes[i]->render(shader, worldToCameraMatrix);
	}

	// Render the floor
	mFloor->render(shader, worldToCameraMatrix);

	// Unbind the shader
	shader.unbind();
}

// Reset the scene
void JointsScene::reset() {

	openglframework::vec3 positionBox(0, 15, 5);
	openglframework::vec3 boxDimension(1, 1, 1);

	for (int32_t i=0; i<NB_BALLSOCKETJOINT_BOXES; i++) {

		// Initial position and orientation of the rigid body
		ephysics::vec3 initPosition(positionBox.x(), positionBox.y(), positionBox.z());
		ephysics::etk::Quaternion initOrientation = ephysics::Quaternion::identity();
		ephysics::etk::Transform3D transform(initPosition, initOrientation);

		// Create a box and a corresponding rigid in the dynamics world
		mBallAndSocketJointChainBoxes[i]->resetTransform(transform);

		positionBox.y() -= boxDimension.y + 0.5f;
	}

	// --------------- Slider Joint --------------- //

	// Position of the box
	openglframework::vec3 positionBox1(0, 2.1f, 0);
	ephysics::vec3 initPosition(positionBox1.x(), positionBox1.y(), positionBox1.z());
	ephysics::etk::Quaternion initOrientation = ephysics::Quaternion::identity();
	ephysics::etk::Transform3D transformBottomBox(initPosition, initOrientation);

	// Create a box and a corresponding rigid in the dynamics world
	mSliderJointBottomBox->resetTransform(transformBottomBox);

	// Position of the box
	openglframework::vec3 positionBox2(0, 4.2f, 0);
	initPosition = ephysics::vec3(positionBox2.x(), positionBox2.y(), positionBox2.z());
	initOrientation = ephysics::etk::Quaternion::identity();
	ephysics::etk::Transform3D transformTopBox(initPosition, initOrientation);

	// Create a box and a corresponding rigid in the dynamics world
	mSliderJointTopBox->resetTransform(transformTopBox);

	// --------------- Propeller Hinge joint --------------- //

	// Position of the box
	positionBox1 = openglframework::vec3(0, 7, 0);
	initPosition = ephysics::vec3(positionBox1.x(), positionBox1.y(), positionBox1.z());
	initOrientation = ephysics::etk::Quaternion::identity();
	ephysics::etk::Transform3D transformHingeBox(initPosition, initOrientation);

	// Create a box and a corresponding rigid in the dynamics world
	mPropellerBox->resetTransform(transformHingeBox);

	// --------------- Fixed joint --------------- //

	// Position of the box
	positionBox1 = openglframework::vec3(5, 7, 0);
	initPosition = ephysics::vec3(positionBox1.x(), positionBox1.y(), positionBox1.z());
	initOrientation = ephysics::etk::Quaternion::identity();
	ephysics::etk::Transform3D transformFixedBox1(initPosition, initOrientation);

	// Create a box and a corresponding rigid in the dynamics world
	mFixedJointBox1->resetTransform(transformFixedBox1);

	// Position of the box
	positionBox2 = openglframework::vec3(-5, 7, 0);
	initPosition = ephysics::vec3(positionBox2.x(), positionBox2.y(), positionBox2.z());
	initOrientation = ephysics::etk::Quaternion::identity();
	ephysics::etk::Transform3D transformFixedBox2(initPosition, initOrientation);

	// Create a box and a corresponding rigid in the dynamics world
	mFixedJointBox2->resetTransform(transformFixedBox2);
}

// Create the boxes and joints for the Ball-and-Socket joint example
void JointsScene::createBallAndSocketJoints() {

	// --------------- Create the boxes --------------- //

	openglframework::vec3 positionBox(0, 15, 5);
	openglframework::vec3 boxDimension(1, 1, 1);
	const float boxMass = 0.5f;

	for (int32_t i=0; i<NB_BALLSOCKETJOINT_BOXES; i++) {

		// Create a box and a corresponding rigid in the dynamics world
		mBallAndSocketJointChainBoxes[i] = new Box(boxDimension, positionBox , boxMass,
												   mDynamicsWorld);

		// Set the box color
		mBallAndSocketJointChainBoxes[i]->setColor(mDemoColors[i % mNbDemoColors]);
		mBallAndSocketJointChainBoxes[i]->setSleepingColor(mRedColorDemo);

		// The fist box cannot move (static body)
		if (i == 0) {
			mBallAndSocketJointChainBoxes[i]->getRigidBody()->setType(ephysics::STATIC);
		}

		// Add some angular velocity damping
		mBallAndSocketJointChainBoxes[i]->getRigidBody()->setAngularDamping(ephysics::float(0.2));

		// Change the material properties of the rigid body
		ephysics::Material& material = mBallAndSocketJointChainBoxes[i]->getRigidBody()->getMaterial();
		material.setBounciness(ephysics::float(0.4));

		positionBox.y() -= boxDimension.y + 0.5f;
	}

	// --------------- Create the joints --------------- //

	for (int32_t i=0; i<NB_BALLSOCKETJOINT_BOXES-1; i++) {

		// Create the joint info object
		ephysics::RigidBody* body1 = mBallAndSocketJointChainBoxes[i]->getRigidBody();
		ephysics::RigidBody* body2 = mBallAndSocketJointChainBoxes[i+1]->getRigidBody();
		ephysics::vec3 body1Position = body1->getTransform().getPosition();
		ephysics::vec3 body2Position = body2->getTransform().getPosition();
		const ephysics::vec3 m_anchorPointWorldSpace = 0.5 * (body1Position + body2Position);
		ephysics::BallAndSocketJointInfo jointInfo(body1, body2, m_anchorPointWorldSpace);

		// Create the joint in the dynamics world
		mBallAndSocketJoints[i] = dynamic_cast<ephysics::BallAndSocketJoint*>(
					mDynamicsWorld->createJoint(jointInfo));
	}
}

/// Create the boxes and joint for the Slider joint example
void JointsScene::createSliderJoint() {

	// --------------- Create the first box --------------- //

	// Position of the box
	openglframework::vec3 positionBox1(0, 2.1f, 0);

	// Create a box and a corresponding rigid in the dynamics world
	openglframework::vec3 box1Dimension(2, 4, 2);
	mSliderJointBottomBox = new Box(box1Dimension, positionBox1 , BOX_MASS, mDynamicsWorld);

	// Set the box color
	mSliderJointBottomBox->setColor(mBlueColorDemo);
	mSliderJointBottomBox->setSleepingColor(mRedColorDemo);

	// The fist box cannot move
	mSliderJointBottomBox->getRigidBody()->setType(ephysics::STATIC);

	// Change the material properties of the rigid body
	ephysics::Material& material1 = mSliderJointBottomBox->getRigidBody()->getMaterial();
	material1.setBounciness(0.4f);

	// --------------- Create the second box --------------- //

	// Position of the box
	openglframework::vec3 positionBox2(0, 4.2f, 0);

	// Create a box and a corresponding rigid in the dynamics world
	openglframework::vec3 box2Dimension(1.5f, 4, 1.5f);
	mSliderJointTopBox = new Box(box2Dimension, positionBox2, BOX_MASS, mDynamicsWorld);

	// Set the box color
	mSliderJointTopBox->setColor(mOrangeColorDemo);
	mSliderJointTopBox->setSleepingColor(mRedColorDemo);

	// Change the material properties of the rigid body
	ephysics::Material& material2 = mSliderJointTopBox->getRigidBody()->getMaterial();
	material2.setBounciness(0.4f);

	// --------------- Create the joint --------------- //

	// Create the joint info object
	ephysics::RigidBody* body1 = mSliderJointBottomBox->getRigidBody();
	ephysics::RigidBody* body2 = mSliderJointTopBox->getRigidBody();
	const ephysics::vec3& body1Position = body1->getTransform().getPosition();
	const ephysics::vec3& body2Position = body2->getTransform().getPosition();
	const ephysics::vec3 m_anchorPointWorldSpace = ephysics::0.5f * (body2Position + body1Position);
	const ephysics::vec3 sliderAxisWorldSpace = (body2Position - body1Position);
	ephysics::SliderJointInfo jointInfo(body1, body2, m_anchorPointWorldSpace, sliderAxisWorldSpace,
									ephysics::float(-1.7), ephysics::float(1.7));
	jointInfo.isMotorEnabled = true;
	jointInfo.motorSpeed = 0.0;
	jointInfo.maxMotorForce = 10000.0;
	jointInfo.isCollisionEnabled = false;

	// Create the joint in the dynamics world
	mSliderJoint = dynamic_cast<ephysics::SliderJoint*>(mDynamicsWorld->createJoint(jointInfo));
}

/// Create the boxes and joint for the Hinge joint example
void JointsScene::createPropellerHingeJoint() {

	// --------------- Create the propeller box --------------- //

	// Position of the box
	openglframework::vec3 positionBox1(0, 7, 0);

	// Create a box and a corresponding rigid in the dynamics world
	openglframework::vec3 boxDimension(10, 1, 1);
	mPropellerBox = new Box(boxDimension, positionBox1 , BOX_MASS, mDynamicsWorld);

	// Set the box color
	mPropellerBox->setColor(mYellowColorDemo);
	mPropellerBox->setSleepingColor(mRedColorDemo);

	// Change the material properties of the rigid body
	ephysics::Material& material = mPropellerBox->getRigidBody()->getMaterial();
	material.setBounciness(ephysics::float(0.4));

	// --------------- Create the Hinge joint --------------- //

	// Create the joint info object
	ephysics::RigidBody* body1 = mPropellerBox->getRigidBody();
	ephysics::RigidBody* body2 = mSliderJointTopBox->getRigidBody();
	const ephysics::vec3& body1Position = body1->getTransform().getPosition();
	const ephysics::vec3& body2Position = body2->getTransform().getPosition();
	const ephysics::vec3 m_anchorPointWorldSpace = 0.5 * (body2Position + body1Position);
	const ephysics::vec3 hingeAxisWorldSpace(0, 1, 0);
	ephysics::HingeJointInfo jointInfo(body1, body2, m_anchorPointWorldSpace, hingeAxisWorldSpace);
	jointInfo.isMotorEnabled = true;
	jointInfo.motorSpeed = - ephysics::0.5f * PI;
	jointInfo.maxMotorTorque = ephysics::float(60.0);
	jointInfo.isCollisionEnabled = false;

	// Create the joint in the dynamics world
	mPropellerHingeJoint = dynamic_cast<ephysics::HingeJoint*>(mDynamicsWorld->createJoint(jointInfo));
}

/// Create the boxes and joints for the fixed joints
void JointsScene::createFixedJoints() {

	// --------------- Create the first box --------------- //

	// Position of the box
	openglframework::vec3 positionBox1(5, 7, 0);

	// Create a box and a corresponding rigid in the dynamics world
	openglframework::vec3 boxDimension(1.5, 1.5, 1.5);
	mFixedJointBox1 = new Box(boxDimension, positionBox1 , BOX_MASS, mDynamicsWorld);

	// Set the box color
	mFixedJointBox1->setColor(mPinkColorDemo);
	mFixedJointBox1->setSleepingColor(mRedColorDemo);

	// Change the material properties of the rigid body
	ephysics::Material& material1 = mFixedJointBox1->getRigidBody()->getMaterial();
	material1.setBounciness(ephysics::float(0.4));

	// --------------- Create the second box --------------- //

	// Position of the box
	openglframework::vec3 positionBox2(-5, 7, 0);

	// Create a box and a corresponding rigid in the dynamics world
	mFixedJointBox2 = new Box(boxDimension, positionBox2 , BOX_MASS, mDynamicsWorld);

	// Set the box color
	mFixedJointBox2->setColor(mBlueColorDemo);
	mFixedJointBox2->setSleepingColor(mRedColorDemo);

	// Change the material properties of the rigid body
	ephysics::Material& material2 = mFixedJointBox2->getRigidBody()->getMaterial();
	material2.setBounciness(ephysics::float(0.4));

	// --------------- Create the first fixed joint --------------- //

	// Create the joint info object
	ephysics::RigidBody* body1 = mFixedJointBox1->getRigidBody();
	ephysics::RigidBody* propellerBody = mPropellerBox->getRigidBody();
	const ephysics::vec3 m_anchorPointWorldSpace1(5, 7, 0);
	ephysics::FixedJointInfo jointInfo1(body1, propellerBody, m_anchorPointWorldSpace1);
	jointInfo1.isCollisionEnabled = false;

	// Create the joint in the dynamics world
	mFixedJoint1 = dynamic_cast<ephysics::FixedJoint*>(mDynamicsWorld->createJoint(jointInfo1));

	// --------------- Create the second fixed joint --------------- //

	// Create the joint info object
	ephysics::RigidBody* body2 = mFixedJointBox2->getRigidBody();
	const ephysics::vec3 m_anchorPointWorldSpace2(-5, 7, 0);
	ephysics::FixedJointInfo jointInfo2(body2, propellerBody, m_anchorPointWorldSpace2);
	jointInfo2.isCollisionEnabled = false;

	// Create the joint in the dynamics world
	mFixedJoint2 = dynamic_cast<ephysics::FixedJoint*>(mDynamicsWorld->createJoint(jointInfo2));
}

// Create the floor
void JointsScene::createFloor() {

	// Create the floor
	openglframework::vec3 floorPosition(0, 0, 0);
	mFloor = new Box(FLOOR_SIZE, floorPosition, FLOOR_MASS, mDynamicsWorld);

	// Set the box color
	mFloor->setColor(mGreyColorDemo);
	mFloor->setSleepingColor(mGreyColorDemo);

	// The floor must be a static rigid body
	mFloor->getRigidBody()->setType(ephysics::STATIC);

	// Change the material properties of the rigid body
	ephysics::Material& material = mFloor->getRigidBody()->getMaterial();
	material.setBounciness(ephysics::float(0.3));
}