// Chloe Chao
// LexFilters.java
// October 20, 1997


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

public class LexFilters extends Applet {

// Globals and constants
  private Choice choice;
  private TextArea textArea;
  private Button button;
  private Font font;
  private FontMetrics fontmetrics;
  private static final int UPPERCASE = 0;
  private static final int LOWERCASE = 1;
  private static final int NOISE = 2;
  private static final int BLUR = 3;
  private static final int ENHANCE = 4;

 public void init() {

  // Take care of the font info
  font = new Font("Helvetica", Font.PLAIN, 12);
  fontmetrics = Toolkit.getDefaultToolkit().getFontMetrics( font );
 
  int gx, gy, cols, rows;
  gx = 540; gy = 382;
  cols = (int)((float)(gx-16)/fontmetrics.charWidth('A')) - 1; // subtract 16 for scrollbar
  rows = (int)((float)gy / fontmetrics.getHeight()) - 3;
  System.out.println("rows = " + rows + "  cols = " + cols );
  
  Panel p = new Panel();
  p.setLayout(new GridLayout(0,2));
  // Add the choice menu.
  makeChoice();
  p.add("West", choice);
  // Add the apply button.
  makeButton();
  p.add("East", button);
  validate();
    
  // Use BorderLayout.
  BorderLayout b = new BorderLayout();
  setLayout(b);
    // Add the textArea.
  makeTextArea(rows, cols);
  add( "North", textArea );
  add( "South", p );
  validate();
 

 }// end init()

 public void paint( Graphics g ) {
   paintComponents(g);
 }// end paint()

 public boolean handleEvent(Event e) {
   
    if (e.target == button) {
      String toBeChanged = textArea.getText();
      textArea.setText(change(toBeChanged, choice.getSelectedIndex() ));
      repaint();
      return true;
    }
    else
      return false;
 }

  // Add according to 'chloe chao'.
  // if c then add h
  // if h then add l or a
  // and so on.
 private String addNoise( String input ) {
   StringBuffer output = new StringBuffer( input );
   for( int i=0; i<output.length(); i++ ) {
     switch( output.charAt(i) ) {
     case 'c':
       output.insert( ++i, 'h' );
       break;
     case 'h':
       if( i%2 > 0 )
	 output.insert( ++i, 'l' );
       else
	 output.insert( ++i, 'a' );
       break;
     case 'l':
     case 'a':
       output.insert( ++i, 'o' );
       break;
     case 'o':
       output.insert( ++i, 'e' );
       break;
     default:
       break;
     }// switch
   }
   return output.toString();
 } 

 private String addBlur( String input ) {
   StringBuffer output = new StringBuffer( input );
   for( int i=0; i<output.length(); i++ ) {
     switch( output.charAt(i) ) {
     case 'a':
       output.setCharAt( i, 'e' );
       break;
     case 'b':
       output.setCharAt( i, 'q' );
       break;
     case 'd':
       output.setCharAt( i, 'p' );
       break;
     case 'e':
       output.setCharAt( i, 'a' );
       break;
     case 'g':
       output.setCharAt( i, '6' );
       break;
     case '6':
       output.setCharAt( i, 'g' );
       break;
     case 'm':
       output.setCharAt( i, 'w' );
       break;
     case 'p':
       output.setCharAt( i, 'd' );
       break;
     case 'q':
       output.setCharAt( i, 'b' );
       break;
     case 's':
       output.setCharAt( i, 'z' );
       break;
     case 'n':
       output.setCharAt( i, 'u' );
       break;
     case 'u':
       output.setCharAt( i, 'n' );
       break;
     case 'w':
       output.setCharAt( i, 'm' );
       break;
     case 'z':
       output.setCharAt( i, 's' );
       break;
     case 'A':
       output.setCharAt( i, 'V' );
       break;
     case 'V':
       output.setCharAt( i, 'A' );
       break;
     case 'M':
       output.setCharAt( i, 'W' );
       break;
     case 'W':
       output.setCharAt( i, 'M' );
       break;
     default:
       break;
     }// switch
   }// for
   return output.toString();
 }

  // Reverse the input
 private String addMSG( String input ) {
   StringBuffer output = new StringBuffer( input );
   for( int i=0; i<output.length(); i++ ) {
     output.setCharAt( i, input.charAt( output.length()-1-i ) );
   }// for
   return output.toString();
 }

 private String change( String changeme, int mode ) {
   switch( mode ) {
   case UPPERCASE:
     return changeme.toUpperCase();
   case LOWERCASE:
     return changeme.toLowerCase();
   case NOISE:
     return addNoise( changeme );
   case BLUR:
     return addBlur( changeme );
   case ENHANCE:
     return addMSG( changeme );
   default:
     return null;
   }
 }
   
 private void makeChoice() {
   choice = new Choice();
   choice.addItem("to uppercase");
   choice.addItem("to lowercase");
   choice.addItem("noise");
   choice.addItem("blur = upside down flip");
   choice.addItem("enhance");
 }

 private void makeButton() {
   button = new Button("do it.");
 }  

 private void makeTextArea(int r, int c) {
    
   textArea = new TextArea("Write a JAVA program with a TextArea widget, a Choice widget, and a Button widget.", r, c);
 }

}// end Caps