//-- BaseConverter
// <applet code="BaseConverter.java" width="254" height="140"></applet>
import java.awt.*;
import java.applet.*;

public class BaseConverter extends Applet {
	final Color myColor = new Color(200,200,200);
	Choice c_In, 
		 c_Out;
	TextField tf_In,
		    tf_Out;

public void init(){
	c_In  = new Choice();
	c_Out = new Choice();
	for (int i=2;i<=36;i++){
		c_In.addItem(""+i);
		c_Out.addItem(""+i);
	}
	c_In.select(8);
	c_Out.select(6);

	tf_In  = new TextField(10);
	tf_Out = new TextField(10);

	setBackground(myColor);
	setLayout(new BorderLayout());

	Panel p = new Panel();
	p.setLayout(new GridLayout(4,2));

	Panel p1a = new Panel();
	p1a.add(new Label("Base to convert from:"));
	p1a.setLayout(new FlowLayout(FlowLayout.LEFT));

	Panel p1 = new Panel();
	p1.setLayout(new FlowLayout(FlowLayout.LEFT));
	p1.add(c_In);
	p.add(p1a);
	p.add(p1);	


	Panel p2a = new Panel();
	p2a.setLayout(new FlowLayout(FlowLayout.LEFT));
	p2a.add(new Label("Number to convert: "));
	Panel p2 = new Panel();
	p2.setLayout(new FlowLayout(FlowLayout.LEFT));
	p2.add(tf_In);
	p.add(p2a);	
	p.add(p2);	

	Panel p3a = new Panel();
	p3a.setLayout(new FlowLayout(FlowLayout.LEFT));
	p3a.add(new Label("Base to convert to:"));
	Panel p3 = new Panel();
	p3.setLayout(new FlowLayout(FlowLayout.LEFT));
	p3.add(c_Out);	
	p.add(p3a);
	p.add(p3);	
	

	Panel p4a = new Panel();
	p4a.setLayout(new FlowLayout(FlowLayout.LEFT));
	p4a.add(new Label("Converted Result: "));
	Panel p4 = new Panel();
	p4.setLayout(new FlowLayout(FlowLayout.LEFT));
	p4.add(tf_Out);
	p.add(p4a);
	p.add(p4);	
	
	add("Center",p);
	add("South",new Button("Calculate"));
}

	public boolean action(Event evt, Object arg){
		tf_Out.setText("");
		if (arg.equals("Calculate")){
			String s = convertToTen(tf_In.getText(),(int)Integer.parseInt(c_In.getSelectedItem()));
			double y = Double.valueOf(s).doubleValue();
			tf_Out.setText(convertFromTen(y,(int)Integer.parseInt(c_Out.getSelectedItem())));
		}
		return true;
	}
//
//----------------------//----------------------//-------------------
//
	public static String convertToTen(String s1, int base){
		System.out.println("Received: "+s1+" base: "+base);
		String s;
		if (s1.indexOf(".") > 0)
			s = s1.substring(0,s1.indexOf("."));
		else
			s = new String(s1);
		// Convert higher bases to 10
		int []a = new int[s.length()];
		for (int i=0;i<s.length();i++)
			a[s.length()-i-1] = charValueOf(s.charAt(i));

		double x = 0;
		for (int i=0;i<s.length();i++) {
			System.out.print(" "+a[i]);
			x+=a[i]*Math.pow(base,i);
		}
		System.out.println("In base 10 is: "+x);
		return ""+x;
	}

	public static int charValueOf(char c){
		if (c >= 'a' && c <= 'z')
			return (int)Integer.parseInt(""+(int)(c-97+10));

		if (c >= 'A' && c <= 'Z')
			return (int)Integer.parseInt(""+(int)(c-'A'+10));

		if (c >= '0' && c <= '9')
			return (int)Integer.parseInt(""+(char)c);
		
		return 0;
	}
//
//----------------------//----------------------//-------------------
//
	public static char intValueOf(int x){
		if (x >= 0 && x <= 9)
			return (char)('0'+x);
		if (x >= 10)
			return (char)('a'+(x-10));

		return 0;
	}


	public static String convertFromTen(double num, int toBase){
		String s = "";
		int i = findLargest(num,toBase);
		while (num > 0.0000000001 || i >= 0) {
			if (s.length()>20)
				num = 0.0;
			if (i == -1)
				s+=".";
		System.out.println("G: "+findNumLargest(num,toBase,i));
			s+=""+intValueOf(findNumLargest(num,toBase,i));
			num -= Math.pow(toBase,i)*findNumLargest(num,toBase,i);
			i--;

		}
		return s;
	}

	public static int findLargest(double num, int toBase){
		int n=0;
		while (Math.pow(toBase,n) <= num)
			n++;
		return n-1;
	}

	public static int findNumLargest(double num, int toBase,int t){
		int n=1;
		while (n*Math.pow(toBase,t) <= num)
			n++;
		return n-1;
	}


} // _Class