/** ZoomHandler.java:       Handles the mouse clicks on the PlotCanvas 
 *  Daryl Rauhala           
 */
import java.awt.*;
import java.awt.event.*;

/**
 * This class will handle the mouse clicks on the PlotCanvas 
 * and reset the PlotCanvas to the bounds set by the two mouse clicks
 * as well as set the textFields to show the new domain of the PlotCanvas
 * area.
 */

class ZoomHandler extends MouseAdapter {

  private InputPanel ip;
  private PlotCanvas pc;
  private static boolean firstClick = true;
  private static double tempX1, tempY1 ;

 public ZoomHandler(PlotCanvas plotcanvas, InputPanel inputpanel ) 
   {
    pc = plotcanvas;
    ip = inputpanel;  
   }
  
 public void mouseReleased( MouseEvent e )
   {
      double tempX2, tempY2, maxX, maxY, minX, minY;  
      tempX2 = tempY2 = 0 ;

    if (firstClick) 
       {
        tempX1 = pc.scaleMouseX( e.getX() );
        tempY1 = pc.scaleMouseY( e.getY() );
        firstClick = false;
       }
    else
       {
        tempX2 = pc.scaleMouseX( e.getX() );
        tempY2 = pc.scaleMouseY( e.getY() );
        firstClick = true;      
       
/**
 * Decide the max and min of the clicked values
 */

      if ( tempX1 > tempX2 )
        {
           maxX = tempX1;   
           minX = tempX2;
        }
      else 
        {
           maxX = tempX2;   
           minX = tempX1;
        }

      if ( tempY1 > tempY2 )
        {
           maxY = tempY1;   
           minY = tempY2;
        }
      else 
        {
           maxY = tempY2;   
           minY = tempY1;
        }

/**
 * send these values to the plotcanvas and redraw the PlotCanvas
 * also set the input fields of the Frame to tell the user the new 
 * dimensions of the viewing area.
 */
       pc.setUserDomain(maxX, maxY, minX, minY);
       pc.setInitState( (maxX - minX)/2, (maxY - minY)/2 );
       ip.setFields(maxX, maxY, minX, minY, (maxX - minX)/2, 
                   (maxY - minY)/2 , ip.getA(), ip.getB(), ip.getIterations() );
       pc.repaint();
    
    } // end of big if 

   }// end of mouseReleased

/** 
 * A static method to reset the number of clicks received
 */

public static void setClickNumber( boolean value ) 
   {
   firstClick = value;              // reset the mouse click variable
   }

} // end of ZoomHandler class