/*   
ZZTextView.java
 *    
 *    Copyright (c) 1999, Ted Nelson and Tuomas Lukka
 *
 *    You may use and distribute under the terms of either the GNU Lesser
 *    General Public License, either version 2 of the license or,
 *    at your choice, any later version. Alternatively, you may use and
 *    distribute under the terms of the XPL.
 *
 *    See the LICENSE.lgpl and LICENSE.xpl files for the specific terms of 
 *    the licenses.
 *
 *    This software is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the README
 *    file for more details.
 *
 */
/*
 * Written by Tuomas Lukka, rewritten to use AWT by Benja Fallenstein
 */
package org.gzigzag;
import java.awt.event.*;
import java.awt.*;

/** A text view showing the contents of one cell (the cursor).
 *  This is shown in a window of its own, using the AWT TextArea component,
 *  to allow copy-and-paste functions as you know them from PUIs. Basically,
 *  it's a dirty hack, because it's outside the usual GZZ framework.
 */

public class ZZTextView extends Frame implements ZZView {
public static final String rcsid = "$Id: ZZTextView.java,v 1.16.2.3 2001/08/16 13:50:01 bfallenstein Exp $";
    static final boolean dbg = false;
    static final void p(String s) { if(dbg) System.out.println(s); }
    static final void pa(String s) { System.out.println(s); }

    ZZCell windowCell;

    /** The cell we show (i.e., the cell currently accursed).
     *  If reraster is called, but the cell and its text haven't changed, we do
     *  nothing, so that the cursor position will not be screwed. (The text
     *  is not cached, instead the text in the TextArea component is used: this
     *  way, if the TextArea itself is used for editing, the text we find there
     *  will be the new text in the cell, so we will not screw the cursor
     *  position either.)
     *  <p>
     *  Note that we simply ignore updates when we have the focus.
     */
    ZZCell shown;

    /** Whether we're updating the content of the TextArea right now.
     *  When we're updating (i.e., write stuff from the structure into
     *  the text area), we obviously ignore events telling us the content
     *  of the text area has changed.
     */
    boolean isUpdating = false;

    /** Whether the text component currently has the focus. */
    boolean hasFocus;

    public ZZCell getViewcell() { return windowCell; }
    public void paintNow(float fract) {}

    TextArea txt = new TextArea("", 100, 100,
				TextArea.SCROLLBARS_VERTICAL_ONLY);

    public ZZTextView(ZZCell c) {
	windowCell = c;
	setLayout(new BorderLayout());
	add(txt, "Center");
	ZZUpdateManager.addView(this);
	txt.addTextListener(new TextListener() {
		public void textValueChanged(TextEvent e) {
		    if(isUpdating) return;
		    shown.setText(txt.getText());
		    ZZCursorReal.setOffs(windowCell, txt.getCaretPosition());
		}
	});
	txt.addFocusListener(new FocusListener() {
		public void focusGained(FocusEvent e) { hasFocus = true; }
		public void focusLost(FocusEvent e) { hasFocus = false; }
	});
	setBounds(0, 0, 200, 300);
	setVisible(true);
	reraster();
    }

    public boolean reraster() { 
	ZZCell accursed = ZZCursorReal.get(windowCell);
	if(!hasFocus && (!accursed.equals(shown) ||
			 !accursed.getText().equals(txt.getText()))) {
	    isUpdating = true;
	    txt.setText(accursed.getText());
	    int offs = ZZCursorReal.getOffs(windowCell);
	    if(offs == ZZCursorReal.NO_OFFSET) 
		txt.setCaretPosition(0);
	    else 
		txt.setCaretPosition(offs);
	    shown = accursed;
	    isUpdating = false;
	}
	return false;
    }
}