import javax.swing.JEditorPane;
import javax.swing.JScrollPane;
import javax.swing.text.html.HTMLEditorKit;
import javax.swing.text.html.HTMLDocument;
import java.net.URL;
import javax.swing.JOptionPane;
import java.io.IOException;
import javax.swing.event.HyperlinkListener;
import javax.swing.event.HyperlinkEvent;
import javax.swing.text.html.HTMLFrameHyperlinkEvent;


/**
 * This class is a simple html viewer. It is able to render html files and display them.
 * 
 * @author Brad Rippe (brippe@fullcoll.edu)
 * @version 1.0
 */
public class HTMLViewer extends JScrollPane {

    /**
     * Constructs a HTMLViewer
     * To construct this in a JFrame simply call "HTMLViewer htmlViewer = new HTMLViewer(this);"
     * @param the main JFrame application component
     */
    public HTMLViewer(URLSetable browser) {
		super(new JEditorPane());
        this.browser = browser;
        editor = (JEditorPane) getViewport().getView();
        editor.setContentType("text/html");
        editor.setEditable(false);
        editor.setEditorKit(new javax.swing.text.html.HTMLEditorKit());

        editor.addHyperlinkListener(new HyperlinkListener() {
            public void hyperlinkUpdate(HyperlinkEvent e) {
				if (e.getEventType() == HyperlinkEvent.EventType.ACTIVATED) {
					JEditorPane pane = (JEditorPane) e.getSource();
					setWebPage(e.getURL());
				}
			}
        });

        setWebPage("http://cis226.fullcoll.edu/index.cfm");
    }

    /**
     * This method set the web page to be displayed.
     * @param url - this uniform resource locator of the new page, this must start with "http://"
     */
    public void setWebPage(String url) {
        try {
			editor.setPage(new URL(url));
            currentURL = url;
            browser.setURLTextField(currentURL);
        } catch (IOException e) {
			JOptionPane.showMessageDialog(null,
                						  "Error retrieving specified URL",
                                          "Bad URL",
                                          JOptionPane.ERROR_MESSAGE);
		}
    }

    /**
     * This method set the web page to be displayed, this method is for internal use only.
     * @param url - this uniform resource locator of the new page, this must start with "http://"
     */
    public void setWebPage(URL url) {
        try {
			editor.setPage(url);
            currentURL = "http://" + url.getHost() + url.getPath();
            browser.setURLTextField(currentURL);
        } catch (IOException e) {
			JOptionPane.showMessageDialog(null,
                						  "Error retrieving specified URL",
                                          "Bad URL",
                                          JOptionPane.ERROR_MESSAGE);
		}
    }

    /**
     * Returns the current url.
     */
    public String getCurrentURL() {
		return currentURL;
    }

    private JEditorPane editor;
    private String currentURL = null;
    private String backURL = null;
    private String forwardURL = null;
    private HTMLDocument htmlDoc;
    private URLSetable browser;
}