ModInfoArea.java

package net.vhati.modmanager.ui;

import java.awt.Color;
import java.awt.Cursor;
import java.awt.Desktop;
import java.awt.event.MouseEvent;
import java.net.URI;
import javax.swing.JScrollPane;
import javax.swing.JTextPane;
import javax.swing.event.MouseInputAdapter;
import javax.swing.text.AttributeSet;
import javax.swing.text.BadLocationException;
import javax.swing.text.DefaultStyledDocument;
import javax.swing.text.SimpleAttributeSet;
import javax.swing.text.Style;
import javax.swing.text.StyleConstants;
import javax.swing.text.StyleContext;
import javax.swing.text.StyledDocument;

import net.vhati.modmanager.ui.Statusbar;

import org.apache.logging.log4j.LogManager;
import org.apache.logging.log4j.Logger;


public class ModInfoArea extends JScrollPane {

	private static final Logger log = LogManager.getLogger(ModInfoArea.class);

	private static final String STYLE_REGULAR = "regular";
	private static final String STYLE_HYPERLINK = "hyperlink";
	private static final String STYLE_TITLE = "title";
	private static final String ATTR_HYPERLINK_TARGET = "hyperlink-target";

	public static Color COLOR_HYPER = Color.BLUE;
	public static final StyleContext DEFAULT_STYLES = ModInfoArea.getDefaultStyleContext();

	private Statusbar statusbar = null;

	private JTextPane textPane;
	private StyledDocument doc;
	private boolean browseWorks;


	public ModInfoArea() {
		this( DEFAULT_STYLES );
	}

	public ModInfoArea( StyleContext styleContext ) {
		super();

		textPane = new JTextPane();
		textPane.setEditable( false );

		doc = new DefaultStyledDocument(styleContext);
		textPane.setStyledDocument(doc);

		Desktop desktop = Desktop.isDesktopSupported() ? Desktop.getDesktop() : null;
		if ( desktop != null && desktop.isSupported(Desktop.Action.BROWSE) ) {
			browseWorks = true;
		}


		MouseInputAdapter hyperlinkListener = new MouseInputAdapter() {
			private Cursor defaultCursor = new Cursor(Cursor.DEFAULT_CURSOR);
			private Cursor linkCursor = new Cursor(Cursor.HAND_CURSOR);
			private boolean wasOverLink = false;

			@Override
			public void mouseClicked( MouseEvent e ) {
				AttributeSet tmpAttr = doc.getCharacterElement( textPane.viewToModel(e.getPoint()) ).getAttributes();
				Object targetObj = tmpAttr.getAttribute( ATTR_HYPERLINK_TARGET );
				if ( targetObj != null ) {
					Desktop desktop = Desktop.isDesktopSupported() ? Desktop.getDesktop() : null;
					if ( desktop != null && desktop.isSupported(Desktop.Action.BROWSE) ) {
						try {
							desktop.browse( new URI(targetObj.toString()) );
						}
						catch ( Exception f ) {
							log.error( "Error browsing clicked url: "+ targetObj.toString(), f );
						}
					}
				}
			}

			@Override
			public void mouseMoved( MouseEvent e ) {
				AttributeSet tmpAttr = doc.getCharacterElement( textPane.viewToModel(e.getPoint()) ).getAttributes();
				Object targetObj = tmpAttr.getAttribute( ATTR_HYPERLINK_TARGET );
				if ( targetObj != null ) {
					textPane.setCursor( linkCursor );
					if ( statusbar != null )
						statusbar.setStatusText( targetObj.toString() );
					wasOverLink = true;
				}
				else {
					if ( wasOverLink ) {
						textPane.setCursor( defaultCursor );
						if ( statusbar != null )
							statusbar.setStatusText( "" );
					}
					wasOverLink = false;
				}
			}
		};
		textPane.addMouseListener( hyperlinkListener );
		textPane.addMouseMotionListener( hyperlinkListener );

		textPane.addMouseListener( new ClipboardMenuMouseListener() );

		this.setViewportView( textPane );
	}


	public void setDescription( String title, String body ) {
		setDescription( title, null, null, null, body );
	}

	public void setDescription( String title, String author, String version, String url, String body ) {
		Style regularStyle = doc.getStyle( STYLE_REGULAR );
		try {
			doc.remove( 0, doc.getLength() );
			doc.insertString( doc.getLength(), title +"\n", doc.getStyle( STYLE_TITLE ) );

			boolean first = true;
			if ( author != null ) {
				doc.insertString( doc.getLength(), String.format("%sby %s", (first ? "" : " "), author), regularStyle );
				first = false;
			}
			if ( version != null ) {
				doc.insertString( doc.getLength(), String.format("%s(version %s)", (first ? "" : " "), version), regularStyle );
				first = false;
			}
			if ( !first ) {
				doc.insertString( doc.getLength(), "\n", regularStyle );
			}

			if ( url != null ) {
				doc.insertString( doc.getLength(), "Website: ", regularStyle );

				if ( browseWorks && url.matches("^(?:https?|ftp)://.*") ) {
					SimpleAttributeSet tmpAttr = new SimpleAttributeSet( doc.getStyle( STYLE_HYPERLINK ) );
					tmpAttr.addAttribute( ATTR_HYPERLINK_TARGET, url );
					doc.insertString( doc.getLength(), "Link", tmpAttr );
				} else {
					doc.insertString( doc.getLength(), url, regularStyle );
				}

				doc.insertString( doc.getLength(), "\n", regularStyle );
			}

			doc.insertString( doc.getLength(), "\n", regularStyle );

			if ( body != null ) {
				doc.insertString( doc.getLength(), body, regularStyle );
			}
		}
		catch ( BadLocationException e) {
			log.error( "Error filling info text area.", e );
		}

		textPane.setCaretPosition(0);
	}


	public void setCaretPosition( int n ) {
		textPane.setCaretPosition( n );
	}

	public void clear() {
		try {
			doc.remove( 0, doc.getLength() );
		}
		catch ( BadLocationException e) {
			log.error( "Error clearing info text area.", e );
		}
	}

	public void appendTitleText( String s ) throws BadLocationException {
		doc.insertString( doc.getLength(), s, doc.getStyle( STYLE_TITLE ) );
	}

	public void appendRegularText( String s ) throws BadLocationException {
		doc.insertString( doc.getLength(), s, doc.getStyle( STYLE_REGULAR ) );
	}

	public void appendLinkText( String linkURL, String linkTitle ) throws BadLocationException {
		if ( browseWorks && linkURL.matches("^(?:https?|ftp)://.*") ) {
			SimpleAttributeSet tmpAttr = new SimpleAttributeSet( doc.getStyle( STYLE_HYPERLINK ) );
			tmpAttr.addAttribute( ATTR_HYPERLINK_TARGET, linkURL );
			doc.insertString( doc.getLength(), linkTitle, tmpAttr );
		} else {
			doc.insertString( doc.getLength(), linkURL, doc.getStyle( STYLE_REGULAR ) );
		}
	}


	/**
	 * Sets a component with a statusbar to be set during mouse events.
	 */
	public void setStatusbar( Statusbar comp ) {
		this.statusbar = comp;
	}


	private static StyleContext getDefaultStyleContext() {
		StyleContext result = new StyleContext();
		Style defaultStyle = StyleContext.getDefaultStyleContext().getStyle( StyleContext.DEFAULT_STYLE );
		Style baseStyle = result.addStyle("base", defaultStyle);

		Style regularStyle = result.addStyle( STYLE_REGULAR, baseStyle );
		StyleConstants.setFontFamily( regularStyle, "Monospaced" );
		StyleConstants.setFontSize( regularStyle, 12 );

		Style hyperStyle = result.addStyle( STYLE_HYPERLINK, regularStyle );
		StyleConstants.setForeground( hyperStyle, COLOR_HYPER );
		StyleConstants.setUnderline( hyperStyle, true );

		Style titleStyle = result.addStyle( STYLE_TITLE, baseStyle );
		StyleConstants.setFontFamily( titleStyle, "SansSerif" );
		StyleConstants.setFontSize( titleStyle, 24 );
		StyleConstants.setBold( titleStyle, true );

		return result;
	}
}