// $Id: UMLPlainTextDocument.java,v 1.25 2004/09/14 20:12:16 mvw Exp $
// Copyright (c) 1996-2004 The Regents of the University of California. All
// Rights Reserved. Permission to use, copy, modify, and distribute this
// software and its documentation without fee, and without a written
// agreement is hereby granted, provided that the above copyright notice
// and this paragraph appear in all copies.  This software program and
// documentation are copyrighted by The Regents of the University of
// California. The software program and documentation are supplied "AS
// IS", without any accompanying services from The Regents. The Regents
// does not warrant that the operation of the program will be
// uninterrupted or error-free. The end-user understands that the program
// was developed for research purposes and is advised not to rely
// exclusively on the program for any reason.  IN NO EVENT SHALL THE
// UNIVERSITY OF CALIFORNIA BE LIABLE TO ANY PARTY FOR DIRECT, INDIRECT,
// SPECIAL, INCIDENTAL, OR CONSEQUENTIAL DAMAGES, INCLUDING LOST PROFITS,
// ARISING OUT OF THE USE OF THIS SOFTWARE AND ITS DOCUMENTATION, EVEN IF
// THE UNIVERSITY OF CALIFORNIA HAS BEEN ADVISED OF THE POSSIBILITY OF
// SUCH DAMAGE. THE UNIVERSITY OF CALIFORNIA SPECIFICALLY DISCLAIMS ANY
// WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
// MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. THE SOFTWARE
// PROVIDED HEREUNDER IS ON AN "AS IS" BASIS, AND THE UNIVERSITY OF
// CALIFORNIA HAS NO OBLIGATIONS TO PROVIDE MAINTENANCE, SUPPORT,
// UPDATES, ENHANCEMENTS, OR MODIFICATIONS.

package org.argouml.uml.ui;

import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.PlainDocument;

import org.apache.log4j.Logger;
import org.argouml.model.ModelFacade;
import org.argouml.model.uml.UmlModelEventPump;
import org.argouml.ui.targetmanager.TargetEvent;
import org.argouml.ui.targetmanager.TargetListener;
import org.tigris.gef.presentation.Fig;

import ru.novosoft.uml.MElementEvent;
import ru.novosoft.uml.MElementListener;

/**
 * A new model for a textproperty. This model does not use reflection to reach 
 * its goal and will perform better therefore. Furthermore, it only reacts to 
 * events that are meant for this model which improves maintainability and 
 * performance. 
 *
 * @since Oct 6, 2002
 * @author jaap.branderhorst@xs4all.nl
 */
public abstract class UMLPlainTextDocument
    extends PlainDocument
    implements MElementListener, TargetListener {

    private static final Logger LOG =
        Logger.getLogger(UMLPlainTextDocument.class);

    /**
     * True if an event should be fired when the text of the document is changed
     */
    private boolean firing = true;

    /**
     * True if an user edits the document directly (by typing in text)
     */
    private boolean editing = false;

    /**
     * The target of the propertypanel that's behind this property.
     */
    private Object panelTarget = null;

    /**
     * The name of the property set event that will change the
     * property this document shows.
     */
    private String eventName = null;

    /**
     * Constructor for UMLPlainTextDocument. This takes a panel to set the
     * thirdpartyeventlistener to the given list of events to listen to.
     *
     * @param name the event
     */
    public UMLPlainTextDocument(String name) {
        super();
        setEventName(name);
    }

    /**
     * @see ru.novosoft.uml.MElementListener#propertySet(ru.novosoft.uml.MElementEvent)
     */
    public void propertySet(MElementEvent e) {
        handleEvent();
    }

    /**
     * @see ru.novosoft.uml.MElementListener#roleAdded(ru.novosoft.uml.MElementEvent)
     */
    public void roleAdded(MElementEvent e) { }

    /**
     * @see ru.novosoft.uml.MElementListener#roleRemoved(ru.novosoft.uml.MElementEvent)
     */
    public void roleRemoved(MElementEvent e) { }

    /**
     * @see ru.novosoft.uml.MElementListener#listRoleItemSet(ru.novosoft.uml.MElementEvent)
     */
    public void listRoleItemSet(MElementEvent e) { }

    /**
     * @see ru.novosoft.uml.MElementListener#removed(ru.novosoft.uml.MElementEvent)
     */
    public void removed(MElementEvent e) { }

    /**
     * @see ru.novosoft.uml.MElementListener#recovered(ru.novosoft.uml.MElementEvent)
     */
    public void recovered(MElementEvent e) { }

    /**
     * Returns the target.
     * @return Object
     */
    public final Object getTarget() {
        return panelTarget;
    }

    /**
     * Sets the target.
     * @param target The target to set
     */
    public final void setTarget(Object target) {
        target = target instanceof Fig ? ((Fig) target).getOwner() : target;
        if (ModelFacade.isABase(target)) {
            UmlModelEventPump eventPump = UmlModelEventPump.getPump();
            if (panelTarget != null) {
                eventPump.removeModelEventListener(this, panelTarget,
						   getEventName());
            }
            panelTarget = target;
            // UmlModelEventPump.getPump().removeModelEventListener(this,
            // (MBase)_target, getEventName());
            eventPump.addModelEventListener(this, panelTarget, getEventName());
            handleEvent();
        }
    }

    /**
     * @see javax.swing.text.Document#insertString(
     *         int, java.lang.String, javax.swing.text.AttributeSet)
     */
    public void insertString(int offset, String str, AttributeSet a)
        throws BadLocationException {
        super.insertString(offset, str, a);
        if (isFiring()) {
            setFiring(false);
            setProperty(getText(0, getLength()));
            setFiring(true);
        }

    }

    /**
     * @see javax.swing.text.Document#remove(int, int)
     */
    public void remove(int offs, int len) throws BadLocationException {
        super.remove(offs, len);
        if (isFiring()) {
            setFiring(false);
            setProperty(getText(0, getLength()));
            setFiring(true);
        }
    }

    /**
     * @param text the value of the property
     */
    protected abstract void setProperty(String text);

    /**
     * @return the value of the property
     */
    protected abstract String getProperty();

    private final void setFiring(boolean f) {
        UmlModelEventPump eventPump = UmlModelEventPump.getPump();
        if (f && panelTarget != null) {
            eventPump.addModelEventListener(this, panelTarget, eventName);
        }
        else {
            eventPump.removeModelEventListener(this, panelTarget, eventName);
        }
        firing = f;
    }

    private final boolean isFiring() {
        return firing;
    }

    private final void handleEvent() {
        try {
            setFiring(false);
            super.remove(0, getLength());
            super.insertString(0, getProperty(), null);
        } catch (BadLocationException b) {
            LOG.error(
		      "A BadLocationException happened\n"
		      + "The string to set was: "
		      + getProperty(),
		      b);
        } finally {
            setFiring(true);
        }
    }

    /**
     * Returns the editing.
     * @return boolean
     */
    public boolean isEditing() {
        return editing;
    }

    /**
     * Sets the editing.
     * @param ed The editing to set
     */
    public void setEditing(boolean ed) {
        editing = ed;       
    }

    /**
     * Returns the eventName.
     * @return String
     */
    public String getEventName() {
        return eventName;
    }

    /**
     * Sets the eventName.
     * @param en The eventName to set
     */
    protected void setEventName(String en) {
        eventName = en;
    }

    /**
     * @see org.argouml.ui.targetmanager.TargetListener#targetAdded(org.argouml.ui.targetmanager.TargetEvent)
     */
    public void targetAdded(TargetEvent e) {
        setTarget(e.getNewTarget());
    }

    /**
     * @see org.argouml.ui.targetmanager.TargetListener#targetRemoved(org.argouml.ui.targetmanager.TargetEvent)
     */
    public void targetRemoved(TargetEvent e) {
        setTarget(e.getNewTarget());
    }

    /**
     * @see org.argouml.ui.targetmanager.TargetListener#targetSet(org.argouml.ui.targetmanager.TargetEvent)
     */
    public void targetSet(TargetEvent e) {
        setTarget(e.getNewTarget());
    }

}