import java.awt.*;
import java.applet.*;

public class hill_climb extends Applet implements Runnable
{

	Thread animator_thread = null;
	Image image;
	int p,q,len = 18;
	int count = 0;
	Button hill,foot,plateau,ridge,start,stop;
	int X1[]={261,261,261,261,261,261,261,261,261,261,261,261,261,261,261};
	int Y1[]={261,261,261,261,261,261,261,261,261,261,261,261,261,261,261};
	int x1=261;int y1=256;int x2=277;int y2=249;
	//For Hill Climbing
	int X[]={261,277,288,298,309,320,334,347,355,366,374,380,384,390,395,396,399,401};
	int Y[]={256,249,238,229,221,213,201,197,185,175,161,149,134,115,100,86,76,70};
	// for foothill problem
	int X2[]={302,307,315,325,341,353,371,387,398,406,415,424,433,439,432};
	int Y2[]={252,245,244,241,238,236,229,222,213,205,194,184,176,166,155};
	//for plateau problem
	int X3[]={165,171,176,186,191,196,202,208,214,222,231,237,245,252,258,265,
		  275,275,268,260,254,235,230,215,208,201,206,211,204};
	int Y3[]={253,249,244,242,243,243,243,241,239,240,238,235,234,233,232,230,
		  226,216,210,208,208,207,206,204,203,195,192,186,183};
	//for ridge problem
	int X4[]={234,240,246,251,257,263,269,276,280,283,286,290,294,299,302,305,308,310,311,313}; 
	int Y4[]={255,254,253,251,249,247,246,245,243,241,239,238,236,235,234,232,230,229,228,227};

public void init()
{ 
        hill = new Button("Hill Climbing");add(hill);
        foot = new Button("Foothill Problem");add(foot);
        plateau=new Button("Plateau Problem");add(plateau);
        ridge = new Button("Ridge Problem");add(ridge);
//        start = new Button("Start");add(start);
//        stop = new Button("Stop");add(stop);

        Graphics g = getGraphics();
        image=getImage(getDocumentBase(),getParameter("image"));
        g.drawImage(image,100,0,this);
		animator_thread = new Thread(this);
		animator_thread.start();
}

//private Thread animator_thread=new Thread(this);
    
public void start() 
{
        Graphics g = getGraphics();
        image=this.getImage(this.getDocumentBase(),this.getParameter("image"));
        g.drawImage(image,100,0,this);
        repaint();
//        X1=X;Y1=Y;
}

public void stop() 
{
        animator_thread.stop();
}

public boolean action(Event e,Object arg){
/*	if (e.target == start)
	{
		animator_thread = new Thread(this);
		animator_thread.start();
	}

	if (e.target == stop)
	{
		stop();
	}
*/
        if(e.target == hill)
	{
		animator_thread = new Thread(this);
		animator_thread.start();
        	X1 = X;
        	Y1 = Y;
        	len = 18;
        }
	else if(e.target == foot)
	{
		animator_thread = new Thread(this);
		animator_thread.start();
        	X1 = X2;
        	Y1 = Y2;
        	len = 15;
        }
 	else if(e.target == plateau)
	{
		animator_thread = new Thread(this);
		animator_thread.start();
        	X1 = X3;
        	Y1 = Y3;
        	len=28;
        } 
 	else if(e.target == ridge)
	{
		animator_thread = new Thread(this);
		animator_thread.start();
  	      	X1 = X4;
        	Y1 = Y4;
        	len=20;  
        }   

return true;
}

public void run() {
        Graphics g = getGraphics();
        g.drawImage(image,0,0,this);
	
	for(int i=0;i<=len;i++){
   		try{
         		p = x2-x1;
         		q = y1-y2;
        		p= Math.max(p,q);
        		q=p;
        		try {Thread.sleep(220);} catch(InterruptedException e){;}
        			draw1();
				x1=X1[i+1]; y1 = Y1[i+1];
				x2=X1[i+2]; y2=Y1[i+2];

      		}catch(ArrayIndexOutOfBoundsException o){;}
        	 catch(NullPointerException npe){;}
        }//end for
}//end run

public void destroy()
{
	image.flush();
}

public void draw1(){
        Graphics g = getGraphics();
        g.drawImage(image,0,0,this);
        g.setColor(Color.green);
        g.fillRect(401,65,8,8);
        draw();
        g.setColor(Color.blue);
        g.drawLine(x1,y1,x1+p,y1);
        try {Thread.sleep(220);} catch(InterruptedException e){;}
        g.drawLine(x1,y1,x1+p,y1-q);
        try {Thread.sleep(220);} catch(InterruptedException e){;}
        g.drawLine(x1,y1,x1,y1-q);
        try {Thread.sleep(220);} catch(InterruptedException e){;}
        g.drawLine(x1,y1,x1-p,y1-q);
        try {Thread.sleep(220);} catch(InterruptedException e){;}
        g.drawLine(x1,y1,x1-p,y1);
        try {Thread.sleep(220);} catch(InterruptedException e){;}
        g.drawLine(x1,y1,x1-p,y1+q);
        try {Thread.sleep(220);} catch(InterruptedException e){;}
        g.drawLine(x1,y1,x1,y1+q);
        try {Thread.sleep(220);} catch(InterruptedException e){;}
        g.drawLine(x1,y1,x1+p,y1+q);
        try {Thread.sleep(220);} catch(InterruptedException e){;}
        g.setColor(Color.green);
        g.drawLine(x1,y1,x2,y2);
//        try {Thread.sleep(220);} catch(InterruptedException e){;}
}

public void draw(){
       Graphics gr = getGraphics();
       gr.setColor(Color.red);
       count++;
 
	for(int i=0;i<count-1;i++)
	{
   		try{
        		gr.drawLine(X1[i],Y1[i],X1[i+1],Y1[i+1]);
        		gr.drawLine(X1[i]+1,Y1[i]+1,X1[i+1]+1,Y1[i+1]+1);  
      			try {Thread.sleep(1);} catch(InterruptedException e){;}
        	}catch(ArrayIndexOutOfBoundsException o){;}
		 catch(NullPointerException npe){;}
        }//end for      
} //end draw

}//end class