/* A simple clipboard with MARK, COPY and PASTE functions */

import javax.microedition.midlet.*;
import javax.microedition.lcdui.*;

public class ClipBoard extends MIDlet implements CommandListener {

  // Refernce to objects
  private Display display; // reference to a Display object
  private TextBox tbClip; // the TextBox
  private Command cmExit; // Exit command
  private Command cmMark; // Command to start Marking a block of Characters
  private Command cmCopy; // copy Command
  private Command cmPaste; // Paste command
  private int StartIndex = 0; // the start Index
  private char[] clip_Board = null; // the clipboard
  private int clipboardchars = 0; // number of characters in clipboard

  // Constructor
  public ClipBoard(){
    display = Display.getDisplay(this);

    // Create commands and set priority
    cmExit = new Command("Exit", Command.EXIT, 1);
    cmMark = new Command("Mark", Command.SCREEN, 2);
    cmCopy = new Command("Copy", Command.SCREEN, 3);
    cmPaste = new Command("Paste", Command.SCREEN, 4);

    tbClip = new TextBox("ClipBoard", "AaBbCcDd", 15, TextField.ANY);

    tbClip.addCommand(cmExit);
    tbClip.addCommand(cmMark);
    tbClip.addCommand(cmCopy);
    tbClip.addCommand(cmPaste);
    tbClip.setCommandListener(this);

    // allocate a clibboard big enough to hold the entire textbox
    clip_Board = new char[tbClip.getMaxSize()];
  }
  // startApp()

  public void startApp(){
    display.setCurrent(tbClip);
  }

  // pauseApp()
  public void pauseApp(){

  }

  // destroyApp()
  public void destroyApp(boolean unconditional){

  }

  public void commandAction(Command c, Displayable s){
    if (c == cmMark){
      StartIndex = tbClip.getCaretPosition(); // get Caret position and store it
    }
    else if (c == cmCopy && (tbClip.getCaretPosition() > StartIndex)) {
      // create an array to hold the current textbox contents
      char[] chr = new char[tbClip.size()];

      // get the current textbox content
      tbClip.getChars(chr);

      // count the characters in the clipboard
      clipboardchars = tbClip.getCaretPosition() - StartIndex;

      // copy text into the clipboard
      // array (source, source index, dest, dest index, count)

      System.arraycopy(chr, StartIndex, clip_Board, 0, clipboardchars);
    }

    else if (c == cmPaste){
      // Make sure the paste will not overrun the textbox length
      if((tbClip.size() + clipboardchars) <= tbClip.getMaxSize())
      tbClip.insert(clip_Board, 0, clipboardchars, tbClip.getCaretPosition());
    }
    else if (c == cmExit){
      destroyApp(false);
      notifyDestroyed();
    }
  }
}