import java.util.*;
import java.awt.*;
import java.io.*;

public class Interaction extends Edge {

  float a1;
  float a2;
  float b1 ;
  boolean vertical = false ;  
  int _type ;
  
  public Interaction( Blackboard b, Node f, Node t, int type ) {
	super( b, f, t );
	_type = type ;
  }


  public float calcCoefDir (int X1, int Y1, int X2, int Y2) {
	float a;

	if ((X1-X2) != 0) {
		a = (float)(Y1-Y2) / (float)(X1-X2);
		vertical = false ;
	}
	else {
		a = 0;
		vertical = true;
	}
	return a;
  }

  public float calcConst (int X, int Y, float a) {
	float b;

	if (! vertical) {
		b = (float)Y - a * (float)X ;
	}
	else {
		b = 0;
	}
	return b;
  }
  
  public double calcCx(double a, double b, int w, int h) {

 	double Cx ;

	if ((_to.X() > _from.X()) && (_to.Y() > _from.Y())) { 
		a2 = calcCoefDir(_to.X(), _to.Y(), _to.X() - w/2, _to.Y() - h/2 ) ;

		if (a1 > a2) {
			Cx = (_to.Y() - h/2 - b) / a1 ;
		}
		else  {
			Cx = _to.X() - w/2 ;
		}
	}
	
	else if ((_to.X() > _from.X()) && (_to.Y() < _from.Y())) { 
		a2 = calcCoefDir(_to.X(), _to.Y(), _to.X()- w/2 , _to.Y() + h/2 ) ;
		if (a1 < a2) {
			Cx = (_to.Y() + h/2 - b) / a1 ;
		}
		else {
			Cx = _to.X() - w/2 ;
		}
	}
		
	else if	((_to.X() < _from.X()) && (_to.Y() > _from.Y())) { 
		a2 = calcCoefDir(_to.X(), _to.Y(), _to.X() + w/2 , _to.Y() - h/2 ) ;
		if (a1 < a2) {
			Cx = (_to.Y() - h/2 - b) / a1 ;
		}
		else {
			Cx = _to.X() + w/2 ;
		}
	}
		
	else {	// ((_to.X() < _from.X()) && (_to.Y() < _from.Y()))  
		a2 = calcCoefDir(_to.X(), _to.Y(), _to.X() + w/2, _to.Y() + h/2 ) ;
		if (a1 >= a2) {
			Cx = (_to.Y() + h/2 - b) / a1 ;
		}
		else {
			Cx = _to.X() + w/2 ;
		}
	}
	return Cx + 0.5 ;			
  }

  public double calcCy(double a, double b, int w, int h) {
  
	double Cy ;

	if ((_to.X() > _from.X()) && (_to.Y() > _from.Y())) { 
		a2 = calcCoefDir(_to.X(), _to.Y(), _to.X() - w/2, _to.Y() - h/2 ) ;

		if (a1 > a2) {
			Cy = _to.Y() - h/2 ;
		}
		else {
			Cy = (_to.X() - w/2) * a1 + b ;
		}
	}
	
	else if ((_to.X() > _from.X()) && (_to.Y() < _from.Y())) { 
		a2 = calcCoefDir(_to.X(), _to.Y(), _to.X() - w/2, _to.Y() + h/2 ) ;

		if (a1 < a2) {
			Cy = _to.Y() + h/2  ;
		}
		else {
			Cy = (_to.X() - w/2) * a1 + b ;
		}
	}
		
	else if	((_to.X() < _from.X()) && (_to.Y() > _from.Y())) { 
		a2 = calcCoefDir(_to.X(), _to.Y(), _to.X() + w/2, _to.Y() - h/2 ) ;

		if (a1 < a2) {
			Cy = _to.Y() - h/2 ;
		}
		else {
			Cy = (_to.X() + w/2) * a1 + b ;
		}
	}
		
	else { 	// ((_to.X() < _from.X()) && (_to.Y() < _from.Y()))  
		a2 = calcCoefDir(_to.X(), _to.Y(), _to.X() + w/2, _to.Y() + h/2 ) ;

		if (a1 > a2) {
			Cy = _to.Y() + h/2  ;
		}
		else {
			Cy = (_to.X() + w/2) * a1 + b ;
		}
	}
	return Cy + 0.5 ;			
  }

  public double calcFromX(double a, double b, int w, int h) {

 	double Cx ;

	if ((_to.X() > _from.X()) && (_to.Y() > _from.Y())) { 
		a2 = calcCoefDir(_from.X(), _from.Y(), _from.X() + w/2, _from.Y() + h/2 ) ;

		if (a1 > a2) {
			Cx = (_from.Y() + h/2 - b) / a1 ;
		}
		else  {
			Cx = _from.X() + w/2 ;
		}
	}
	
	else if ((_to.X() > _from.X()) && (_to.Y() < _from.Y())) { 
		a2 = calcCoefDir(_from.X(), _from.Y(), _from.X() + w/2 , _from.Y() - h/2 ) ;
		if (a1 < a2) {
			Cx = (_from.Y() - h/2 - b) / a1 ;
		}
		else {
			Cx = _from.X() + w/2 ;
		}
	}
		
	else if	((_to.X() < _from.X()) && (_to.Y() > _from.Y())) { 
		a2 = calcCoefDir(_from.X(), _from.Y(), _from.X() - w/2 , _from.Y() + h/2 ) ;
		if (a1 < a2) {
			Cx = (_from.Y() + h/2 - b) / a1 ;
		}
		else {
			Cx = _from.X() - w/2 ;
		}
	}
		
	else {	// ((_to.X() < _from.X()) && (_to.Y() < _from.Y()))  
		a2 = calcCoefDir(_from.X(), _from.Y(), _from.X() - w/2, _from.Y() - h/2 ) ;
		if (a1 >= a2) {
			Cx = (_from.Y() - h/2 - b) / a1 ;
		}
		else {
			Cx = _from.X() - w/2 ;
		}
	}
	return Cx + 0.5 ;			
  }

  public double calcFromY(double a, double b, int w, int h) {
  
	double Cy ;

	if ((_to.X() > _from.X()) && (_to.Y() > _from.Y())) { 
		a2 = calcCoefDir(_from.X(), _from.Y(), _from.X() + w/2, _from.Y() + h/2 ) ;

		if (a1 > a2) {
			Cy = _from.Y() + h/2 ;
		}
		else {
			Cy = (_from.X() + w/2) * a1 + b ;
		}
	}
	
	else if ((_to.X() > _from.X()) && (_to.Y() < _from.Y())) { 
		a2 = calcCoefDir(_from.X(), _from.Y(), _from.X() + w/2, _from.Y() - h/2 ) ;

		if (a1 < a2) {
			Cy = _from.Y() - h/2  ;
		}
		else {
			Cy = (_from.X() + w/2) * a1 + b ;
		}
	}
		
	else if	((_to.X() < _from.X()) && (_to.Y() > _from.Y())) { 
		a2 = calcCoefDir(_from.X(), _from.Y(), _from.X() - w/2, _from.Y() + h/2 ) ;

		if (a1 < a2) {
			Cy = _from.Y() + h/2 ;
		}
		else {
			Cy = (_from.X() - w/2) * a1 + b ;
		}
	}
		
	else { 	// ((_to.X() < _from.X()) && (_to.Y() < _from.Y()))  
		a2 = calcCoefDir(_from.X(), _from.Y(), _from.X() - w/2, _from.Y() - h/2 ) ;

		if (a1 > a2) {
			Cy = _from.Y() - h/2  ;
		}
		else {
			Cy = (_from.X() - w/2) * a1 + b ;
		}
	}
	return Cy + 0.5 ;			
  }

  public void paint(Graphics g) {

	double cx;
	double cy;
	double cxFrom;
	double cyFrom;

	int decal = 6 ;

	if (_dir == -1 ) swapDir();
		
        int w_to = _to.boundingWidth() + decal;
        int h_to = _to.boundingHeight() + decal;

        int w_from = _from.boundingWidth() + decal;
        int h_from = _from.boundingHeight() + decal;

	a1 = calcCoefDir(_to.X(), _to.Y(), _from.X(), _from.Y()) ;

	b1 = calcConst(_to.X(), _to.Y(), a1) ;

        int dX = _to.X()-_from.X();
        int dY = _to.Y()-_from.Y();
        double len = Math.sqrt( dX*dX + dY*dY );
        double ndx = arrowSize*dX/len;
        double ndy = arrowSize*dY/len;


	if ( (_to.X() != _from.X()) && (_to.Y() != _from.Y()) ) {
	        cx = calcCx(a1,b1,w_to,h_to) ;
	        cy = calcCy(a1,b1,w_to,h_to) ;
		cxFrom = calcFromX(a1,b1,w_from,h_from);
		cyFrom = calcFromY(a1,b1,w_from,h_from);
	}

	else if ( (_to.X() == _from.X()) && (_to.Y() != _from.Y()) ){
		cx = _to.X() ;
		cxFrom = _to.X() ;
		if (_to.Y() > _from.Y()) {
			cy = _to.Y() - h_to/2 ;
			cyFrom = _from.Y() + h_from/2 ;
		}
		else {
			cy = _to.Y() + h_to/2 ;
			cyFrom = _from.Y() - h_from/2 ;
		}
	}

	else {
		if (_to.X() > _from.X()) {
		   cx = _to.X() - w_to/2 ;
		   cxFrom = _from.X() + w_from/2 ;
		}
		else {
		   cx = _to.X() + w_to/2 ;
		   cxFrom = _from.X() - w_from/2 ;
		}
		cy = _to.Y() ;
		cyFrom = _to.Y() ;
	}	 

        g.setColor( edgeColor );
	
	g.drawLine( (int)cxFrom , (int)cyFrom , (int)cx , (int)cy );

	if (_type == 1) { // activation
		g.drawLine( (int)cx , (int)cy , (int)(cx + ndy - ndx), (int)(cy - ndx -ndy) ); 
		g.drawLine( (int)cx , (int)cy , (int)(cx - ndy - ndx), (int)(cy + ndx -ndy ) ); 
	}
	else if (_type == -1) { // inhibition
		g.drawLine( (int)cx , (int)cy , (int)(cx - ndy), (int)(cy + ndx) ); 
		g.drawLine( (int)cx , (int)cy , (int)(cx + ndy), (int)(cy - ndx ) ); 
	}
	else { // activation et inhibition
		g.drawLine( (int)cx , (int)cy , (int)(cx + ndy - ndx), (int)(cy - ndx -ndy) ); 
		g.drawLine( (int)cx , (int)cy , (int)(cx - ndy - ndx), (int)(cy + ndx -ndy ) ); 
		g.drawLine( (int)cx , (int)cy , (int)(cx - ndy), (int)(cy + ndx) ); 
		g.drawLine( (int)cx , (int)cy , (int)(cx + ndy), (int)(cy - ndx ) ); 
	}

	if (_dir == -1 ) swapDir();
		
  }

} // class Interaction