CanvasNodeName.java

/*
 * Copyright (C) 2012 Jason Gedge <http://www.gedge.ca>
 *
 * This file is part of the OpGraph project.
 * 
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program 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
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package ca.gedge.opgraph.app.components.canvas;

import java.awt.Font;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.Rectangle;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;

import javax.swing.JTextField;
import javax.swing.SwingConstants;
import javax.swing.border.EmptyBorder;
import javax.swing.event.UndoableEditListener;
import javax.swing.undo.UndoableEditSupport;

import ca.gedge.opgraph.OpNode;
import ca.gedge.opgraph.OpNodeAdapter;
import ca.gedge.opgraph.app.components.DoubleClickableTextField;
import ca.gedge.opgraph.app.edits.node.ChangeNodeNameEdit;
import ca.gedge.opgraph.app.util.GUIHelper;

/**
 * A text field that displays the name of a node. Supports undo/redo.
 */
public class CanvasNodeName extends JTextField {
	/** Double-click support */
	private DoubleClickableTextField doubleClickSupport;

	/** The node whose name this component is showing */
	private OpNode node;

	/** The style used for this component */
	private NodeStyle style;

	/** Undo support for node name edits */
	private UndoableEditSupport undoSupport;

	/**
	 * Constructs a name component that references the given node.
	 * 
	 * @param node  the node
	 * @param style  the node style
	 * 
	 * @throws NullPointerException  if the specified node is <code>null</code> 
	 */
	public CanvasNodeName(OpNode node, NodeStyle style) {
		this.doubleClickSupport = new DoubleClickableTextField(this);
		this.undoSupport = new UndoableEditSupport();

		setHorizontalAlignment(CENTER);
		setFont(getFont().deriveFont(Font.BOLD));
		setNode(node);
		setStyle(style);

		this.doubleClickSupport.addPropertyChangeListener(DoubleClickableTextField.TEXT_PROPERTY, textListener);
	}

	/**
	 * Gets the node whose name is displayed by this component.
	 *  
	 * @return the node
	 */
	public OpNode getNode() {
		return node;
	}

	/**
	 * Sets the node whose name is displayed by this component.
	 * 
	 * @param node  the node
	 * 
	 * @throws NullPointerException  if the specified node is <code>null</code>
	 */
	public void setNode(OpNode node) {
		if(node == null) throw new NullPointerException("node cannot be null");

		if(this.node != null)
			this.node.removeNodeListener(nodeListener);

		this.node = node;
		this.node.addNodeListener(nodeListener);

		// Update component
		setBorder(new EmptyBorder(2, 5, 2, 5));
		setText(node.getName());
		setToolTipText(node.getDescription());
	}

	/**
	 * Sets the style used for this node.
	 * 
	 * @param style  the node style
	 */
	public void setStyle(NodeStyle style) {
		this.style = (style == null ? new NodeStyle() : style);

		setBackground(this.style.NodeNameTopColor);
		setForeground(this.style.NodeNameTextColor);

		revalidate();
		repaint();
	}

	//
	// Overrides
	//

	@Override
	protected void paintComponent(Graphics gfx) {
		if(doubleClickSupport.isEditing()) {
			super.paintComponent(gfx);
		} else {
			final Graphics2D g = (Graphics2D)gfx;
			final Rectangle rect = GUIHelper.getInterior(this);
			final int halign = getHorizontalAlignment();
			final int valign = SwingConstants.CENTER;
			final Point p = GUIHelper.placeTextInRectangle(g, getText(), rect, halign, valign);

			// Draw shadow under text, if necessary
			if(style.NodeNameTextShadowColor != null) {
				g.setColor(style.NodeNameTextShadowColor);
				g.drawString(getText(), p.x + 1, p.y + 1);
			}

			g.setColor(getForeground());
			g.drawString(getText(), p.x, p.y);
		}
	}

	//
	// OpNodeListener
	//

	final OpNodeAdapter nodeListener = new OpNodeAdapter() {
		@Override
		public void nodePropertyChanged(String propertyName, Object oldValue, Object newValue) {
			if(propertyName.equals(OpNode.NAME_PROPERTY))
				setText((String)newValue);
		}
	}; 

	//
	// DoubleClickableTextField property listener
	//

	private final PropertyChangeListener textListener = new PropertyChangeListener() {
		@Override
		public void propertyChange(PropertyChangeEvent e) {
			if(node != null) {
				String t = (String)e.getNewValue();
				if(t == null || t.trim().length() == 0)
					t = node.getName();

				undoSupport.postEdit(new ChangeNodeNameEdit(node, t));
			}
		}
	};

	//
	// UndoableEdit support
	//

	/**
	 * Adds an undoable edit listener to this component.
	 * 
	 * @param listener  the listener to add
	 */
	public void addUndoableEditListener(UndoableEditListener listener) {
		undoSupport.addUndoableEditListener(listener);
	}

	/**
	 * Removes an undoable edit listener from this component.
	 * 
	 * @param listener  the listener to remove
	 */
	public void removeUndoableEditListener(UndoableEditListener listener) {
		undoSupport.removeUndoableEditListener(listener);
	}
}