/**
 * @(#)Laina.java
 *
 * Laina Applet application
 *
 * @author 
 * @version 1.00 2012/1/11
 */
 
import java.applet.*;
import java.awt.*;
import java.awt.event.*;

public class Laina extends Applet implements ActionListener {

 	TextField tpo, tai, tkk;
	Button bann, btas;
	int ai, i, a;
	double po, kk, ly, ko, ann,r;

 	public void init () {
 		add(tpo = new TextField("150000"));
 		add(tai = new TextField("10"));
 		add(tkk = new TextField("5"));
 		add(bann = new Button("Annuiteetti"));
 		add(btas = new Button("Tasaerä"));	
  		bann.addActionListener(this);
  		btas.addActionListener(this);
 	}

 	public void paint(Graphics g) {
 		g.drawString("Pääoma:",5,33);
 		g.drawString("Aika:",5,53);
 		g.drawString("Korkokanta:",5,73);
 		g.drawString("Annuiteetti:  "+Math.round(ann),5,93);
 		tpo.reshape(70, 20, 70, 20);
 		tai.reshape(70, 40, 70, 20);
 		tkk.reshape(70, 60, 70, 20);
 		bann.reshape(70, 120, 70, 30);
		btas.reshape(70, 150, 70, 30); 	
			
		g.drawString("Vuosi",150,13);
		g.drawString("Lyhennys",200,13);
		g.drawString("Korko",300,13);
		g.drawString("Pääoma",400,13);
				
		for ( i = 1 ; i <= ai ; i++ ) {
			g.drawString(""+i,150,13+i*15);
			g.drawString(""+Math.round(ly),200,13+i*15);
			g.drawString(""+Math.round(ko),300,13+i*15);
			g.drawString(""+Math.round(po),400,13+i*15);
			if (a==0) {
				po=po-ly;
				ko=kk*po/100;
				ly=ann-ko;
			} 
			if (a==1){
				po=po-ly;
				ko=kk*po/100;
			}	
		}
 	}
 	public void actionPerformed(ActionEvent e) {
 		if (e.getActionCommand().equals("Annuiteetti")){
			po=Double.valueOf(tpo.getText());
 			ai=Integer.valueOf(tai.getText());
 			kk=Double.valueOf(tkk.getText());
 			r = ( 100 + kk ) / 100;
 			ann=po*(Math.pow(r,ai)*(r-1))/(Math.pow(r,ai)-1);
 			ko=kk*po/100;
 			ly=ann-ko;
 			a=0;
 			repaint();
 		}
 		if (e.getActionCommand().equals("Tasaerä")){
 			ann=0;
 			po=Double.valueOf(tpo.getText());
 			ai=Integer.valueOf(tai.getText());
 			kk=Double.valueOf(tkk.getText());
 			ko=kk*po/100;
 			ly=po/ai;
 			a=1;
 			repaint();
 		}
 	}
}