package nl.siegmann.epublib.viewer;
import java.awt.Color;
import java.awt.Desktop;
import java.awt.GridLayout;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;
import java.awt.event.MouseWheelEvent;
import java.awt.event.MouseWheelListener;
import java.io.UnsupportedEncodingException;
import java.net.URL;
import java.net.URLDecoder;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.swing.JEditorPane;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.event.HyperlinkEvent;
import javax.swing.event.HyperlinkListener;
import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.html.HTML;
import javax.swing.text.html.HTMLDocument;
import javax.swing.text.html.HTMLEditorKit;
import nl.siegmann.epublib.Constants;
import nl.siegmann.epublib.browsersupport.NavigationEvent;
import nl.siegmann.epublib.browsersupport.NavigationEventListener;
import nl.siegmann.epublib.browsersupport.Navigator;
import nl.siegmann.epublib.domain.Book;
import nl.siegmann.epublib.domain.Resource;
import org.apache.commons.lang.StringUtils;
/**
* Displays a page
*
* @return
*/
public class ContentPane extends JPanel implements NavigationEventListener,
HyperlinkListener {
private static final long serialVersionUID = -5322988066178102320L;
private static final Logger log = Logger.getLogger(ContentPane.class.getName());
private Navigator navigator;
private Resource currentResource;
private JEditorPane editorPane;
private JScrollPane scrollPane;
private HTMLDocumentFactory htmlDocumentFactory;
public ContentPane(Navigator navigator) {
super(new GridLayout(1, 0));
this.scrollPane = (JScrollPane) add(new JScrollPane());
this.scrollPane.addKeyListener(new KeyAdapter() {
@Override
public void keyPressed(KeyEvent e) {
if (e.getKeyCode() == KeyEvent.VK_DOWN) {
Point viewPosition = scrollPane.getViewport().getViewPosition();
int newY = (int) (viewPosition.getY() + 10);
scrollPane.getViewport().setViewPosition(new Point((int) viewPosition.getX(), newY));
}
}
});
this.scrollPane.addMouseWheelListener(new MouseWheelListener() {
private boolean gotoNextPage = false;
private boolean gotoPreviousPage = false;
@Override
public void mouseWheelMoved(MouseWheelEvent e) {
int notches = e.getWheelRotation();
int increment = scrollPane.getVerticalScrollBar().getUnitIncrement(1);
if (notches < 0) {
Point viewPosition = scrollPane.getViewport().getViewPosition();
if (viewPosition.getY() - increment < 0) {
if (gotoPreviousPage) {
gotoPreviousPage = false;
ContentPane.this.navigator.gotoPreviousSpineSection(-1, ContentPane.this);
} else {
gotoPreviousPage = true;
scrollPane.getViewport().setViewPosition(new Point((int) viewPosition.getX(), 0));
}
}
} else {
// only move to the next page if we are exactly at the bottom of the current page
Point viewPosition = scrollPane.getViewport().getViewPosition();
int viewportHeight = scrollPane.getViewport().getHeight();
int scrollMax = scrollPane.getVerticalScrollBar().getMaximum();
if (viewPosition.getY() + viewportHeight + increment > scrollMax) {
if (gotoNextPage) {
gotoNextPage = false;
ContentPane.this.navigator.gotoNextSpineSection(ContentPane.this);
} else {
gotoNextPage = true;
int newY = scrollMax - viewportHeight;
scrollPane.getViewport().setViewPosition(new Point((int) viewPosition.getX(), newY));
}
}
}
}
});
this.navigator = navigator;
navigator.addNavigationEventListener(this);
this.editorPane = createJEditorPane();
scrollPane.getViewport().add(editorPane);
this.htmlDocumentFactory = new HTMLDocumentFactory(navigator, editorPane.getEditorKit());
initBook(navigator.getBook());
}
private void initBook(Book book) {
if (book == null) {
return;
}
htmlDocumentFactory.init(book);
displayPage(book.getCoverPage());
}
/**
* Whether the given searchString matches any of the possibleValues.
*
* @param searchString
* @param possibleValues
* @return
*/
private static boolean matchesAny(String searchString, String... possibleValues) {
for (int i = 0; i < possibleValues.length; i++) {
String attributeValue = possibleValues[i];
if (StringUtils.isNotBlank(attributeValue) && (attributeValue.equals(searchString))) {
return true;
}
}
return false;
}
/**
* Scrolls the editorPane to the startOffset of the current element in the elementIterator
*
* @param requestFragmentId
* @param attributeValue
* @param editorPane
* @param elementIterator
*
* @return whether it was a match and we jumped there.
*/
private static void scrollToElement(JEditorPane editorPane, HTMLDocument.Iterator elementIterator) {
try {
Rectangle rectangle = editorPane.modelToView(elementIterator.getStartOffset());
if (rectangle == null) {
return;
}
// the view is visible, scroll it to the
// center of the current visible area.
Rectangle visibleRectangle = editorPane.getVisibleRect();
// r.y -= (vis.height / 2);
rectangle.height = visibleRectangle.height;
editorPane.scrollRectToVisible(rectangle);
} catch (BadLocationException e) {
log.warning(e.getMessage());
}
}
/**
* Scrolls the editorPane to the first anchor element whose id or name matches the given fragmentId.
*
* @param fragmentId
*/
private void scrollToNamedAnchor(String fragmentId) {
HTMLDocument doc = (HTMLDocument) editorPane.getDocument();
for (HTMLDocument.Iterator iter = doc.getIterator(HTML.Tag.A); iter.isValid(); iter.next()) {
AttributeSet attributes = iter.getAttributes();
if (matchesAny(fragmentId, (String) attributes.getAttribute(HTML.Attribute.NAME),
(String) attributes.getAttribute(HTML.Attribute.ID))) {
scrollToElement(editorPane, iter);
break;
}
}
}
private JEditorPane createJEditorPane() {
JEditorPane editorPane = new JEditorPane();
editorPane.setBackground(Color.white);
editorPane.setEditable(false);
HTMLEditorKit htmlKit = new HTMLEditorKit();
// StyleSheet myStyleSheet = new StyleSheet();
// String normalTextStyle = "font-size: 12px, font-family: georgia";
// myStyleSheet.addRule("body {" + normalTextStyle + "}");
// myStyleSheet.addRule("p {" + normalTextStyle + "}");
// myStyleSheet.addRule("div {" + normalTextStyle + "}");
// htmlKit.setStyleSheet(myStyleSheet);
editorPane.setEditorKit(htmlKit);
editorPane.addHyperlinkListener(this);
editorPane.addKeyListener(new KeyAdapter() {
@Override
public void keyPressed(KeyEvent keyEvent) {
if (keyEvent.getKeyCode() == KeyEvent.VK_RIGHT) {
navigator.gotoNextSpineSection(ContentPane.this);
} else if (keyEvent.getKeyCode() == KeyEvent.VK_LEFT) {
navigator.gotoPreviousSpineSection(ContentPane.this);
// } else if (keyEvent.getKeyCode() == KeyEvent.VK_UP) {
// ContentPane.this.gotoPreviousPage();
} else if (keyEvent.getKeyCode() == KeyEvent.VK_SPACE) {
// || (keyEvent.getKeyCode() == KeyEvent.VK_DOWN)) {
ContentPane.this.gotoNextPage();
}
}
});
return editorPane;
}
public void displayPage(Resource resource) {
displayPage(resource, 0);
}
public void displayPage(Resource resource, int sectionPos) {
if (resource == null) {
return;
}
try {
HTMLDocument document = htmlDocumentFactory.getDocument(resource);
if (document == null) {
return;
}
currentResource = resource;
editorPane.setDocument(document);
scrollToCurrentPosition(sectionPos);
} catch (Exception e) {
log.log(Level.WARNING, "When reading resource " + resource.getId() + "("
+ resource.getHref() + ") :" + e.getMessage(), e);
}
}
private void scrollToCurrentPosition(int sectionPos) {
if (sectionPos < 0) {
editorPane.setCaretPosition(editorPane.getDocument().getLength());
} else {
editorPane.setCaretPosition(sectionPos);
}
if (sectionPos == 0) {
scrollPane.getViewport().setViewPosition(new Point(0, 0));
} else if (sectionPos < 0) {
int viewportHeight = scrollPane.getViewport().getHeight();
int scrollMax = scrollPane.getVerticalScrollBar().getMaximum();
scrollPane.getViewport().setViewPosition(new Point(0, scrollMax - viewportHeight));
}
}
public void hyperlinkUpdate(HyperlinkEvent event) {
if (event.getEventType() != HyperlinkEvent.EventType.ACTIVATED) {
return;
}
final URL url = event.getURL();
if (url.getProtocol().toLowerCase().startsWith("http") && !"".equals(url.getHost())) {
if(launchBrowser(event.getURL())) {
return;
}
log.log(Level.WARNING, "Couldn't launch system web browser.");
}
String resourceHref = calculateTargetHref(event.getURL());
if (resourceHref.startsWith("#")) {
scrollToNamedAnchor(resourceHref.substring(1));
return;
}
Resource resource = navigator.getBook().getResources().getByHref(resourceHref);
if (resource == null) {
log.warning("Resource with url " + resourceHref + " not found");
} else {
navigator.gotoResource(resource, this);
}
}
public void gotoPreviousPage() {
Point viewPosition = scrollPane.getViewport().getViewPosition();
if (viewPosition.getY() <= 0) {
navigator.gotoPreviousSpineSection(this);
return;
}
int viewportHeight = scrollPane.getViewport().getHeight();
int newY = (int) viewPosition.getY();
newY -= viewportHeight;
newY = Math.max(0, newY - viewportHeight);
scrollPane.getViewport().setViewPosition(
new Point((int) viewPosition.getX(), newY));
}
public void gotoNextPage() {
Point viewPosition = scrollPane.getViewport().getViewPosition();
int viewportHeight = scrollPane.getViewport().getHeight();
int scrollMax = scrollPane.getVerticalScrollBar().getMaximum();
if (viewPosition.getY() + viewportHeight >= scrollMax) {
navigator.gotoNextSpineSection(this);
return;
}
int newY = ((int) viewPosition.getY()) + viewportHeight;
scrollPane.getViewport().setViewPosition(
new Point((int) viewPosition.getX(), newY));
}
/**
* Transforms a link generated by a click on a link in a document to a resource href.
* Property handles http encoded spaces and such.
*
* @param clickUrl
* @return
*/
private String calculateTargetHref(URL clickUrl) {
String resourceHref = clickUrl.toString();
try {
resourceHref = URLDecoder.decode(resourceHref,
Constants.ENCODING);
} catch (UnsupportedEncodingException e) {
log.warning(e.getMessage());
}
resourceHref = resourceHref.substring(ImageLoaderCache.IMAGE_URL_PREFIX
.length());
if (resourceHref.startsWith("#")) {
return resourceHref;
}
if (currentResource != null
&& StringUtils.isNotBlank(currentResource.getHref())) {
int lastSlashPos = currentResource.getHref().lastIndexOf('/');
if (lastSlashPos >= 0) {
resourceHref = currentResource.getHref().substring(0,
lastSlashPos + 1)
+ resourceHref;
}
}
return resourceHref;
}
public void navigationPerformed(NavigationEvent navigationEvent) {
if (navigationEvent.isBookChanged()) {
initBook(navigationEvent.getCurrentBook());
} else {
if (navigationEvent.isResourceChanged()) {
displayPage(navigationEvent.getCurrentResource(),
navigationEvent.getCurrentSectionPos());
} else if (navigationEvent.isSectionPosChanged()) {
editorPane.setCaretPosition(navigationEvent.getCurrentSectionPos());
}
if (StringUtils.isNotBlank(navigationEvent.getCurrentFragmentId())) {
scrollToNamedAnchor(navigationEvent.getCurrentFragmentId());
}
}
}
/**
* Open a URL in the default web browser.
*
* @param a URL to open in a web browser.
* @return true if a browser has been launched.
*/
private static boolean launchBrowser(URL url) {
if (Desktop.isDesktopSupported()) {
try {
Desktop.getDesktop().browse(url.toURI());
return true;
} catch (Exception e) {
e.printStackTrace(); // debug output
}
}
return false;
}
}