#include "simul/element.h"

Element::Element(b2World & world, Position p, Type t)
{
	this->p = p;
	type = t;
	multiplier = 0;

	b2BodyDef bodyDef;
	//bodyDef.type = b2_dynamicBody;
	bodyDef.position.Set(p.x/100., p.y/100.);
	
	body = world.CreateBody(&bodyDef);

	b2CircleDef circleDef;
	circleDef.radius = 1.0f;
	circleDef.localPosition.Set(0.,0.);

	circleDef.density = 1.0f;
	circleDef.friction = 0.4f;
	body->CreateShape(&circleDef);
}

void Element::updatePos()
{
	p.x = 100.*body->GetPosition().x;
	p.y = 100.*body->GetPosition().y;

	float friction = 0.5;
	b2Vec2 velocity = body->GetLinearVelocity();
	float32 speed = velocity.Length();
	
	if(speed > FLT_EPSILON)
	{
		float32 newSpeed = speed - friction;
		if(newSpeed < 0)
			newSpeed = 0;
		velocity *= newSpeed/speed;
		body->SetLinearVelocity(velocity);
	}

	float angularFriction = 0.1;
	float angular = body->GetAngularVelocity();
	if(angular > 0)
	{
		angular -= angularFriction;
		if(angular < 0)
			angular = 0;
	}
	else
	{
		angular += angularFriction;
		if(angular > 0)
			angular = 0;
	}
	body->SetAngularVelocity(angular);
}

void Element::paint(QPainter & pa)
{

	pa.setBrush(QBrush(QColor("yellow")));
	pa.setPen(QBrush(QColor("yellow")));

	pa.drawEllipse(QPoint(p.x,-p.y),100,-100);

	pa.setBrush(QBrush(QColor("black")));
	pa.setPen(QBrush(QColor("black")));
	QFont font;
	font.setPointSize(30);
	pa.setFont(font);

	QString text;
	if(type == Pawn)
	{
		if(multiplier > 0)
			text = QString::number(multiplier);
	}
	else
	{
		if(type == Queen)
			text = "Q";
		else
			text = "K";
		if(multiplier > 0)
			text = QString(" ") + QString::number(multiplier);
	}

	pa.drawText(p.x-50, -p.y+50, 100, -100, Qt::AlignCenter, text);
}
