/*]  Copyright (c) 2009-2010, Charles McGarvey  [**************************
**]  All rights reserved.
*
* vi:ts=4 sw=4 tw=75
*
* Distributable under the terms and conditions of the 2-clause BSD license;
* see the file COPYING for a complete text of the license.
*
**************************************************************************/

#include <iostream>

#include "Character.hh"
#include "Log.hh"

	
class SpringForce
{
public:

	explicit SpringForce(Mf::Vector2 x) :
		location(x) {}

	const Mf::Vector2& operator () (const Mf::LinearState<2>& state)
	{
		Mf::Vector2 x = state.position - location;
		Mf::Scalar mag = x.length();
		Mf::Scalar d = 0.0;

		// spring:
		//mState.force += -15.0 * x - 1.5 * mState.velocity;
		force = SCALAR(-10.0) * (mag - d) * (x / mag);// - SCALAR(2.0) * state.velocity;

		return force;
	}

private:

	Mf::Vector2 force;
	Mf::Vector2 location;
};

class ResistanceForce
{
public:

	explicit ResistanceForce(Mf::Scalar scale = 1.0) :
		k(scale) {}

	const Mf::Vector2& operator () (const Mf::LinearState<2>& state)
	{
		force = -k * state.velocity;
		return force;
	}

private:

	Mf::Vector2	force;
	Mf::Scalar	k;
};


Character::Character(const std::string& name) :
	tilemap(name),
	animation(name)
{
	mState.init();

	mState.mass = 1.0;
	mState.inverseMass = 1.0 / mState.mass;

	// forces
	mState.force = Mf::Vector2(0.0, 0.0);
	//mState.forces.push_back(SpringForce(Mf::Vector2(5.0, 4.0)));
	//mState.forces.push_back(ResistanceForce(2.0));
	//mState.forces.push_back(Mf::LinearState<2>::GravityForce(-9.8));

	// starting position
	mState.position = Mf::Vector2(5.0, 5.0);
	mState.momentum = Mf::Vector2(0.0, 0.0);
	mState.recalculate();

	mPrevState = mState;
}


void Character::update(Mf::Scalar t, Mf::Scalar dt)
{
	Mf::RigidBody2::update(t, dt); // update physics

	animation.update(t, dt);

	Mf::Vector3 center(mState.position[0], mState.position[1], 0.0);
	Mf::Vector3 a(mState.position[0] - 0.5, mState.position[1] - 0.5, 0.0);
	Mf::Vector3 b(mState.position[0] + 0.5, mState.position[1] + 0.5, 0.0);

	mAabb.init(a, b);
	mSphere.init(center, a);
}


void Character::draw(Mf::Scalar alpha) const
{
	Mf::State2 state = getState(alpha);
	Mf::Vector2 position = state.position;

	//glColor3f(1.0f, 1.0f, 1.0f);
	tilemap.bind();

	Mf::Texture::TileIndex frame = animation.getFrame();
	Mf::Texture::Orientation orientation = Mf::Texture::NORMAL;

	if (mState.velocity[0] < 0.0) orientation = Mf::Texture::REVERSE;

	Mf::Scalar coords[8];
	tilemap.getTileCoords(frame, coords, orientation);

	Mf::Scalar s = 0.5;

	glBegin(GL_TRIANGLE_FAN);
		glTexCoord(coords[0], coords[1]);
		glVertex(position[0]-s, position[1]-s);
		glTexCoord(coords[2], coords[3]);
		glVertex(position[0]+s, position[1]-s);
		glTexCoord(coords[4], coords[5]);
		glVertex(position[0]+s, position[1]+s);
		glTexCoord(coords[6], coords[7]);
		glVertex(position[0]-s, position[1]+s);
	glEnd();
}


/*int Character::getOctant(const Mf::Aabb<3>& aabb) const
{
	int octantNum = -1;

	Mf::Plane::Halfspace halfspace;

	Mf::Plane xy = aabb.getPlaneXY();
	halfspace = xy.intersects(mSphere);
	if (halfspace == Mf::Plane::INTERSECT)
	{
		halfspace = xy.intersects(mAabb);
	}

	if (halfspace == Mf::Plane::POSITIVE)
	{
		Mf::Plane xz = aabb.getPlaneXZ();
		halfspace = xz.intersects(mSphere);
		if (halfspace == Mf::Plane::INTERSECT)
		{
			halfspace = xz.intersects(mAabb);
		}

		if (halfspace == Mf::Plane::POSITIVE)
		{
			Mf::Plane yz = aabb.getPlaneYZ();
			halfspace = yz.intersects(mSphere);
			if (halfspace == Mf::Plane::INTERSECT)
			{
				halfspace = yz.intersects(mAabb);
			}

			if (halfspace == Mf::Plane::POSITIVE)
			{
				octantNum = 2;
			}
			else if (halfspace == Mf::Plane::NEGATIVE)
			{
				octantNum = 3;
			}
		}
		else if (halfspace == Mf::Plane::NEGATIVE)
		{
			Mf::Plane yz = aabb.getPlaneYZ();
			halfspace = yz.intersects(mSphere);
			if (halfspace == Mf::Plane::INTERSECT)
			{
				halfspace = yz.intersects(mAabb);
			}

			if (halfspace == Mf::Plane::POSITIVE)
			{
				octantNum = 1;
			}
			else if (halfspace == Mf::Plane::NEGATIVE)
			{
				octantNum = 0;
			}
		}
	}
	else if (halfspace == Mf::Plane::NEGATIVE)
	{
		Mf::Plane xz = aabb.getPlaneXZ();
		halfspace = xz.intersects(mSphere);
		if (halfspace == Mf::Plane::INTERSECT)
		{
			halfspace = xz.intersects(mAabb);
		}

		if (halfspace == Mf::Plane::POSITIVE)
		{
			Mf::Plane yz = aabb.getPlaneYZ();
			halfspace = yz.intersects(mSphere);
			if (halfspace == Mf::Plane::INTERSECT)
			{
				halfspace = yz.intersects(mAabb);
			}

			if (halfspace == Mf::Plane::POSITIVE)
			{
				octantNum = 6;
			}
			else if (halfspace == Mf::Plane::NEGATIVE)
			{
				octantNum = 7;
			}
		}
		else if (halfspace == Mf::Plane::NEGATIVE)
		{
			Mf::Plane yz = aabb.getPlaneYZ();
			halfspace = yz.intersects(mSphere);
			if (halfspace == Mf::Plane::INTERSECT)
			{
				halfspace = yz.intersects(mAabb);
			}

			if (halfspace == Mf::Plane::POSITIVE)
			{
				octantNum = 5;
			}
			else if (halfspace == Mf::Plane::NEGATIVE)
			{
				octantNum = 4;
			}
		}
	}

	return octantNum;
}
*/


void Character::addImpulse(Mf::Vector2 impulse)
{
	mState.momentum += impulse;
}

void Character::addForce(Mf::Vector2 force)
{
	mState.force += force;
}

void Character::setPosition(Mf::Vector2 position)
{
	mState.position = position;
}