/***************************************************************************
 *   Copyright (C) 2005 by David Saxton                                    *
 *   david@bluehaze.org                                                    *
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 ***************************************************************************/

#include "chassiscircular2.h"

#include "libraryitem.h"

#include <klocale.h>
#include <qpainter.h>
#include <qwmatrix.h>

#include <algorithm>
#include <cmath>

double normalizeAngle( double angle );


Item* ChassisCircular2::construct( ItemDocument *itemDocument, bool newItem, const char *id )
{
	return new ChassisCircular2( (MechanicsDocument*)itemDocument, newItem, id );
}


LibraryItem* ChassisCircular2::libraryItem()
{
	return new LibraryItem(
		QString("mech/chassis_circular_2"),
		i18n("Circular 2-Wheel Chassis"),
		i18n("Chassis'"),
		"chassis.png",
		LibraryItem::lit_mechanical,
		ChassisCircular2::construct );
}


ChassisCircular2::ChassisCircular2( MechanicsDocument *mechanicsDocument, bool newItem, const char *id )
	: MechanicsItem( mechanicsDocument, newItem, (id) ? id : "chassis_circular_2" )
{
	m_name = i18n("Circular 2-Wheel Chassis");
	m_desc = i18n("A circular base with two wheels and a support point.");
	
	m_theta1 = 0.0;
	m_theta2 = 0.0;
	
	QPointArray pa;
	pa.makeEllipse( -25, -25, 50, 50 );
	QWMatrix m(4,0,0,4,0,0);
	m.setTransformationMode( QWMatrix::Areas );
	pa = m.map(pa);
	setItemPoints(pa);
	
	itemResized();
}


ChassisCircular2::~ChassisCircular2()
{
}


void ChassisCircular2::itemResized()
{
	const double w = sizeRect().width();
	const double h = sizeRect().height();
	
	m_wheel1Pos = QRect( int(w/5), int(h/6), int(w/4), int(h/8) );
	m_wheel2Pos = QRect( int(w/5), int(5*h/6-h/8), int(w/4), int(h/8) );
}


void ChassisCircular2::advance( int phase )
{
	if ( phase != 1 )
		return;
	
	double speed1 = 60.; // pixels per second
	double speed2 = 160.; // pixels per second
	
	m_theta1 = normalizeAngle( m_theta1 + (speed1/1000.)/m_wheel1Pos.width() );
	m_theta2 = normalizeAngle( m_theta2 + (speed2/1000.)/m_wheel2Pos.width() );
	
	const double d1 = speed1/1000.;
	const double d2 = speed2/1000.;
	const double sep = m_wheel2Pos.center().y()-m_wheel1Pos.center().y();
	
	double dtheta = std::atan( (d2-d1)/sep ); // Change in orientation of chassis
	double moveAngle = absolutePosition().angle()+dtheta/2;
	rotateBy(dtheta);
	moveBy( ((d1+d2)/2.)*std::cos(moveAngle), ((d1+d2)/2.)*std::sin(moveAngle) );
}


void ChassisCircular2::drawShape( QPainter &p )
{
	const double _x = int(sizeRect().x() + x());
	const double _y = int(sizeRect().y() + y());
	const double w = sizeRect().width();
	const double h = sizeRect().height(); 
	
	initPainter(p);
	p.setBrush( QColor( 255, 246, 210 ) );
	QRect circleRect = sizeRect();
	circleRect.moveLeft( int(circleRect.left() + x()) );
	circleRect.moveTop( int(circleRect.top() + y()) );
	p.drawEllipse(circleRect);
	
	// Draw wheels
	// TODO get this info from m_wheel1Pos and m_wheel2Pos
	const double X = _x+(w/5); // Wheel's left pos
	const double H = h/8; // Wheel's height
	const double y1 = _y+(h/6); // Wheel 1 y-pos
	const double y2 = _y+(5*h/6)-H; // Wheel 2 y-pos
	
	p.setPen( Qt::NoPen );
	const double stripeWidth = 5;
	const double offset2 = 1 + int(m_theta1*m_wheel1Pos.width())%int(2*stripeWidth);
	const double offset1 = 1 + int(m_theta2*m_wheel2Pos.width())%int(2*stripeWidth);
	p.setBrush( QColor( 255, 232, 182 ) );
	for ( double i=-1; i<std::ceil(m_wheel1Pos.width()/stripeWidth); ++i )
	{
		
		p.setClipRect( QRect( int(_x+m_wheel1Pos.x()+2), int(_y+m_wheel1Pos.y()+2), int(m_wheel1Pos.width()-4), int(m_wheel1Pos.height()-4) ), QPainter::CoordPainter );
		p.drawRect( int(offset1+X + i*stripeWidth*2), int(y1+1), int(stripeWidth), int(H-2) );
		
		p.setClipRect( QRect( int(_x+m_wheel2Pos.x()+2), int(_y+m_wheel2Pos.y()+2), int(m_wheel2Pos.width()-4), int(m_wheel2Pos.height()-4) ), QPainter::CoordPainter );
		p.drawRect( int(offset2+X + i*stripeWidth*2), int(y2+1), int(stripeWidth), int(H-2) );
	}
	p.setClipping(false);
	
	p.setPen( Qt::black );
	p.setBrush( Qt::NoBrush );
	p.drawRoundRect( int(X), int(y1), int(w/4), int(H), 25, 50 );
	p.drawRoundRect( int(X), int(y2), int(w/4), int(H), 25, 50 );
	
	
	deinitPainter(p);
}
