package genegui;

import java.awt.*;
import java.awt.event.*;
import java.io.*;
import java.net.*;
import java.util.*;
import javax.swing.event.*;
import javax.swing.*;

/** HTMLViewer.java
 A simple HTML Viewer for browsing through Ingeneue help files.
 @author WJS
 */
public class HTMLViewer extends JInternalFrame {
	
	/** Button for navigating back through list of visited links */
	private JButton                     BackButton;
	/** The EditorPane for storing  */
	private JEditorPane                 EditorPane;
	/** Button for navigating forward through list of visited links */
	private JButton                     ForwardButton;
	/** The main pane holds all */
	private JPanel                      MainPane;
	/** The current link in the visited links list */
	private int                         VisitedLinkIndex = 0;
	/** the list of visited links */
	private Vector                      VisitedLinkList;
	
	
	/** Simple constructor
	 @param URL - The url to initialize the Editor pane with
	 */
	public HTMLViewer(URL url) {
		
		super("Ingeneue Help",true,true,true,true);
		
		VisitedLinkList = new Vector();
		
		// Make main pane
		MainPane = new JPanel();
		setContentPane(MainPane);
		MainPane.setLayout(new BorderLayout());
		
		// Make the toolbar
		JToolBar toolBar = new JToolBar();
		toolBar.setBackground(Color.lightGray);
		toolBar.setFloatable(false);
		
		// Back button moves us back to previous page
		BackButton = new JButton(new ImageIcon("icons/HTMLVback.png"));
		BackButton.addActionListener(new ActionListener() {
					public void actionPerformed(ActionEvent ae) {
						if (VisitedLinkIndex>0) {
							VisitedLinkIndex--;
							try {
								EditorPane.setPage((URL)VisitedLinkList.get(VisitedLinkIndex));
							} catch (Exception ex) {
							}
						}
					}
				});
		toolBar.add(BackButton);
		
		// Forward button moves us forward to a page iff back was used
		ForwardButton = new JButton(new ImageIcon("icons/HTMLVforward.png"));
		ForwardButton.addActionListener(new ActionListener() {
					public void actionPerformed(ActionEvent ae) {
						if (VisitedLinkIndex<VisitedLinkList.size()-1) {
							VisitedLinkIndex++;
							try {
								EditorPane.setPage((URL)VisitedLinkList.get(VisitedLinkIndex));
							} catch (Exception ex) {
							}
						}
					}
				});
		toolBar.add(ForwardButton);
		
		MainPane.add(toolBar,BorderLayout.NORTH);
		
		// Make the editor pane
		try {
			EditorPane = new JEditorPane(url);
		  VisitedLinkList.add(url);
			EditorPane.setEditable(false);
			
			// Add a hyperlink listener to handle clicks on links
			EditorPane.addHyperlinkListener(new HyperlinkListener() {
						public void hyperlinkUpdate(HyperlinkEvent e) {
							if (e.getEventType()==HyperlinkEvent.EventType.ENTERED)
								setCursor(new Cursor(Cursor.HAND_CURSOR));
							if (e.getEventType()==HyperlinkEvent.EventType.EXITED)
								setCursor(new Cursor(Cursor.DEFAULT_CURSOR));
							if (e.getEventType()==HyperlinkEvent.EventType.ACTIVATED) {
								try {
									EditorPane.setPage(e.getURL());
									for (int i=VisitedLinkList.size()-1;i>VisitedLinkIndex;i--)
										VisitedLinkList.remove(i);
									VisitedLinkList.add(e.getURL());
									VisitedLinkIndex++;
								} catch (Exception ex) {
									System.out.println("Failed to open url - "+e.getURL().getPath());
								}
							}
						}
					});
		} catch (IOException ioex) {
			System.out.println("File not found - "+url.getPath());
		}
		
		JScrollPane scrollPane = new JScrollPane(EditorPane);
		MainPane.add(scrollPane,BorderLayout.CENTER);
		
		setSize(400,500);
		
	}
	
  /** Sets the page contents according to the URL
	 @param String - url string.
	 @author WJS
	 */
	public void setURL(String urlString) {
		
		try {
		  URL url = new URL(urlString);
			try {
				EditorPane.setPage(url);
			} catch (Exception ex) {
				System.out.println("HTMLViewer - page not found: "+urlString);
			}
		} catch (MalformedURLException mue) {
			System.out.println("HTMLViewer - malformed URL: "+urlString);
		}
		
	}
	
  /** Sets the page contents according to the URL
	 @param URL - the url object.
	 @author WJS
	 */
	public void setURL(URL url) {
		
		try {
			EditorPane.setPage(url);
		} catch (Exception ex) {
			System.out.println("HTMLViewer - page not found");
		}
		
	}
	
}