/*
* Copyright (c) 2008-2011, Piccolo2D project, http://piccolo2d.org
* Copyright (c) 1998-2008, University of Maryland
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without modification, are permitted provided
* that the following conditions are met:
*
* Redistributions of source code must retain the above copyright notice, this list of conditions
* and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice, this list of conditions
* and the following disclaimer in the documentation and/or other materials provided with the
* distribution.
*
* None of the name of the University of Maryland, the name of the Piccolo2D project, or the names of its
* contributors may be used to endorse or promote products derived from this software without specific
* prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
* PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR
* ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR
* TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
* ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
package edu.umd.cs.piccolo.nodes;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.Font;
import java.awt.Graphics2D;
import java.awt.geom.Point2D;
import java.awt.geom.Rectangle2D;
import javax.swing.JLabel;
import javax.swing.plaf.basic.BasicHTML;
import javax.swing.text.Position;
import javax.swing.text.View;
import edu.umd.cs.piccolo.PNode;
import edu.umd.cs.piccolo.util.PPaintContext;
/**
* PHtmlView is a Piccolo node for rendering HTML text. It uses a JLabel under
* the hood so you have the same restrictions regarding HTML as you have when
* using standard Swing components (HTML 3.2 + subset of CSS 1.0).
*
* @since 1.3
* @author Chris Malley (cmal...@pixelzoom.com)
* @author Sam Reid
* @author Allain Lalonde
*/
public class PHtmlView extends PNode {
/** Default serial version UID. */
private static final long serialVersionUID = 1L;
/**
* Default font if not otherwise specified in the HTML text, 12 point
* <code>"SansSerif"</code>.
*/
// public static final Font DEFAULT_FONT = new Font(Font.SANS_SERIF,
// Font.PLAIN, 12); jdk 1.6+
public static final Font DEFAULT_FONT = new Font("SansSerif", Font.PLAIN, 12);
/**
* Default text color if not otherwise specified in the HTML text,
* <code>Color.BLACK</code>.
*/
public static final Color DEFAULT_TEXT_COLOR = Color.BLACK;
/**
* The property name that identifies a change of this node's font (see
* {@link #getFont getFont}). Both old and new value will be set in any
* property change event.
*/
public static final String PROPERTY_FONT = "font";
/**
* The property code that identifies a change of this node's font (see
* {@link #getFont getFont}). Both old and new value will be set in any
* property change event.
*/
public static final int PROPERTY_CODE_FONT = 1 << 20;
/**
* The property name that identifies a change of this node's HTML text (see
* {@link #getText getText}). Both old and new value will be set in any
* property change event.
*/
public static final String PROPERTY_TEXT = "text";
/**
* The property code that identifies a change of this node's HTML text (see
* {@link #getText getText}). Both old and new value will be set in any
* property change event.
*/
public static final int PROPERTY_CODE_TEXT = 1 << 21;
/**
* The property name that identifies a change of this node's HTML text color
* (see {@link #getTextColor getTextColor}). Both old and new value will be set
* in any property change event.
*/
public static final String PROPERTY_TEXT_COLOR = "text color";
/**
* The property code that identifies a change of this node's HTML text color
* (see {@link #getTextColor getTextColor}). Both old and new value will be set
* in any property change event.
*/
public static final int PROPERTY_CODE_TEXT_COLOR = 1 << 22;
/** Underlying JLabel used to handle the rendering logic. */
private final JLabel label;
/** Object that encapsulates the HTML rendering logic. */
private transient View htmlView;
/**
* Create an empty HTML text node with the default font and text color.
*/
public PHtmlView() {
this(null, DEFAULT_FONT, DEFAULT_TEXT_COLOR);
}
/**
* Create a HTML text node with the specified HTML text and the default font
* and text color.
*
* @param text HTML text for this HTML text node
*/
public PHtmlView(final String text) {
this(text, DEFAULT_FONT, DEFAULT_TEXT_COLOR);
}
/**
* Create a HTML text node with the specified HTML text, font, and text
* color. The font and text color are used to render the HTML text if not
* otherwise specified via CSS.
*
* @param text HTML text for this HTML text node
* @param font font for this HTML text node
* @param textColor text color for this HTML text node
*/
public PHtmlView(final String text, final Font font, final Color textColor) {
label = new JLabel(text);
label.setFont(font);
label.setForeground(textColor);
super.setBounds(0, 0, label.getPreferredSize().getWidth(), label.getPreferredSize().getHeight());
update();
}
/**
* Return the HTML text for this HTML text node.
*
* @return the HTML text for this HTML text node
*/
public String getText() {
return label.getText();
}
/**
* Set the HTML text for this HTML text node to <code>text</code>.
*
* <p>
* This is a <b>bound</b> property.
* </p>
*
* @param text HTML text for this HTML text node
*/
public void setText(final String text) {
final String oldText = label.getText();
if (oldText == null && text == null) {
return;
}
if (oldText == null || !oldText.equals(text)) {
label.setText(text);
update();
firePropertyChange(PROPERTY_CODE_TEXT, PROPERTY_TEXT, oldText, label.getText());
}
}
/**
* Return the font for this HTML text node. This font is used to render the
* HTML text if not otherwise specified via CSS. Defaults to
* {@link #DEFAULT_FONT}.
*
* @return the font for this HTML text node
*/
public Font getFont() {
return label.getFont();
}
/**
* Set the font for this HTML text node to <code>font</code>. This font is
* used to render the HTML text if not otherwise specified via CSS.
*
* <p>
* This is a <b>bound</b> property.
* </p>
*
* @param font font for this HTML text node
*/
public void setFont(final Font font) {
final Font oldFont = label.getFont();
label.setFont(font);
update();
firePropertyChange(PROPERTY_CODE_FONT, PROPERTY_FONT, oldFont, label.getFont());
}
/**
* Return the text color for this HTML text node. This text color is used to
* render the HTML text if not otherwise specified via CSS. Defaults to
* {@link #DEFAULT_TEXT_COLOR}.
*
* @return the text color for this HTML text node
*/
public Color getTextColor() {
return label.getForeground();
}
/**
* Set the text color for this HTML text node to <code>textColor</code>.
* This text color is used to render the HTML text if not otherwise
* specified via CSS.
*
* This is a <b>bound</b> property.
*
* @param textColor text color for this HTML text node
*/
public void setTextColor(final Color textColor) {
final Color oldColor = label.getForeground();
label.setForeground(textColor);
repaint();
firePropertyChange(PROPERTY_CODE_TEXT_COLOR, PROPERTY_TEXT_COLOR, oldColor, label.getForeground());
}
/**
* Applies all properties to the underlying JLabel, creates an htmlView and
* updates bounds.
*/
private void update() {
String htmlContent = label.getText();
if (htmlContent == null) {
htmlContent = "";
}
htmlView = BasicHTML.createHTMLView(label, htmlContent);
fitHeightToHtmlContent();
repaint();
}
/**
* Resizes the height to be as tall as its rendered html. Takes wrapping
* into account.
*/
private void fitHeightToHtmlContent() {
if (getWidth() > 0) {
htmlView.setSize((float) getWidth(), 0f);
float wrapHeight = htmlView.getPreferredSpan(View.Y_AXIS);
label.setSize(new Dimension((int) getWidth(), (int) wrapHeight));
if (getHeight() < wrapHeight) {
System.out.println(getHeight());
System.out.println(wrapHeight);
super.setBounds(getX(), getY(), getWidth(), wrapHeight);
}
}
}
/** {@inheritDoc} */
public boolean setBounds(final double x, final double y, final double width, final double height) {
final boolean boundsChanged = super.setBounds(x, y, width, height);
update();
return boundsChanged;
}
/** {@inheritDoc} */
public boolean setBounds(final Rectangle2D newBounds) {
final boolean boundsChanged = super.setBounds(newBounds);
update();
return boundsChanged;
}
/**
* {@inheritDoc}
*
* <p>
* The HTML text is painted last, so it will appear on top of any child
* nodes.
* </p>
*/
protected void paint(final PPaintContext paintContext) {
super.paint(paintContext);
paintContext.pushClip(getBounds());
final Graphics2D g2 = paintContext.getGraphics();
htmlView.paint(g2, getBounds().getBounds());
paintContext.popClip(getBounds());
}
/**
* Return the address specified in the HTML link at the specified point in
* this node's local coordinate system, if any.
*
* @param point point in this node's local coordinate system
* @return the address specified in the HTML link at the specified point in
* this node's local coordinate system, or <code>null</code> if no
* such HTML link exists
*/
public String getLinkAddressAt(final Point2D point) {
return getLinkAddressAt(point.getX(), point.getY());
}
/**
* Return the address specified in the HTML link at the specified x and y
* coordinates in this node's local coordinate system, if any.
*
* @param x x coordinate in this node's local coordinate system
* @param y y coordinate in this node's local coordinate system
* @return the address specified in the HTML link at the specified x and y
* coordinates in this node's local coordinate system, or
* <code>null</code> if no such HTML link exists
*/
public String getLinkAddressAt(final double x, final double y) {
int position = pointToModelIndex(x, y);
final String text = label.getText();
String address = null;
int currentPos = 0;
while (currentPos < text.length()) {
currentPos = text.indexOf('<', currentPos);
if (currentPos == -1 || position < currentPos) {
break;
}
final int tagStart = currentPos;
final int tagEnd = findTagEnd(text, currentPos);
if (tagEnd == -1) {
return null;
}
currentPos = tagEnd + 1;
final String tag = text.substring(tagStart, currentPos);
position += tag.length();
if ("</a>".equals(tag)) {
address = null;
}
else if (tag.startsWith("<a ")) {
address = extractHref(tag);
}
}
return address;
}
/**
* Return the index into the raw text at the specified x and y coordinates
* in this node's local coordinate system.
*
* @param x x coordinate in this node's local coordinate system
* @param y y coordinate in this node's local coordinate system
* @return the index into the raw text at the specified x and y coordinates
* in this node's local coordinate system
*/
private int pointToModelIndex(final double x, final double y) {
final Position.Bias[] biasReturn = new Position.Bias[1];
return htmlView.viewToModel((float) x, (float) y, getBounds(), biasReturn);
}
/**
* Starting from the startPos, find the position at which the given tag
* ends. Returns <code>-1</code> if the end of the string was encountered
* before the end of the tag was encountered.
*
* @param text HTML text being searched
* @param startPos where in the string to start searching for ">"
* @return index after the ">" character
*/
private int findTagEnd(final String text, final int startPos) {
int currentPos = startPos;
currentPos++;
while (currentPos > 0 && currentPos < text.length() && text.charAt(currentPos) != '>') {
if (text.charAt(currentPos) == '\"') {
currentPos = text.indexOf('\"', currentPos + 1);
}
else if (text.charAt(currentPos) == '\'') {
currentPos = text.indexOf('\'', currentPos + 1);
}
currentPos++;
}
if (currentPos == 0 || currentPos >= text.length()) {
return -1;
}
return currentPos + 1;
}
/**
* Given a tag, extracts the value of the href attribute or returns null if
* none was found.
*
* @param tag from which to extract the href value
* @return href value without quotes or <code>null</code> if not found
*/
private String extractHref(final String tag) {
int currentPos = 0;
final String href = null;
while (currentPos >= 0 && currentPos < tag.length() - 1) {
currentPos = tag.indexOf('=', currentPos + 1);
if (currentPos != -1 && isHrefAttributeAssignment(tag, currentPos)) {
return extractHrefValue(tag, currentPos + 1);
}
}
return href;
}
/**
* Starting at the character after the equal sign of an href=..., it extract
* the value. Handles single, double, and no quotes.
*
* @param tag tag
* @param startPos start position
* @return value of href or null if not found.
*/
private String extractHrefValue(final String tag, final int startPos) {
int currentPos = startPos;
if (tag.charAt(currentPos) == '\"') {
final int startHref = currentPos + 1;
currentPos = tag.indexOf('\"', startHref);
if (currentPos == -1) {
return null;
}
return tag.substring(startHref, currentPos);
}
else if (currentPos < tag.length() && tag.charAt(currentPos) == '\'') {
final int startHref = currentPos + 1;
currentPos = tag.indexOf('\'', startHref);
if (currentPos == -1) {
return null;
}
return tag.substring(startHref, currentPos);
}
else {
final int startHref = currentPos;
if (currentPos < tag.length()) {
do {
currentPos++;
} while (currentPos < tag.length() && tag.charAt(currentPos) != ' ' && tag.charAt(currentPos) != '>');
}
return tag.substring(startHref, currentPos);
}
}
/**
* Given the position in a string returns whether it points to the equal
* sign of an href attribute.
*
* @param tag html code of the tag
* @param equalPos the index of the assignment
* @return true if to left of assignment is href
*/
private boolean isHrefAttributeAssignment(final String tag, final int equalPos) {
return tag.charAt(equalPos) == '=' && equalPos > 4 && " href".equals(tag.substring(equalPos - 5, equalPos));
}
}
