import java.awt.*;
import java.awt.event.*;

/**
 * The graphical aspect of this application.
 *
 * @author Marcel Turcotte
 */

public class Viewer extends Frame implements ActionListener {

    private Interpreter lvm; // Luka Virtual Machine

    private Display display;

    private Button bExecute = new Button( "Execute" );

    private TextArea input = new TextArea();

    /**
     * Creates the visual display of the application.  Creates a
     * PostScriptDisplay, Button and TextArea.
     *
     * @param lvm a reference to an interpreter.
     */

    public Viewer( Interpreter lvm ) {

        super( "DrLuka" );

        this.lvm = lvm;

        setBackground( Color.WHITE );

        display = new Display( this );

        display.setSize( 400,400 );
        display.setBackground( Color.WHITE );

        add( display,BorderLayout.CENTER );

        bExecute.addActionListener( this );

        Panel control = new Panel();
        control.setLayout( new FlowLayout() );
        control.add( bExecute );

        Panel console = new Panel();
        console.setLayout( new BorderLayout() );

        input.setBackground( Color.WHITE );

        console.add( input, BorderLayout.CENTER );
        console.add( control, BorderLayout.SOUTH );

        add( console, BorderLayout.SOUTH );

        /**
         * Calls display.repaint(), which in turns calls the method
         * paint of the component with a reference to the Graphics
         * object.  Finally, the method paint calls our own method
         */

        addWindowListener( new WindowAdapter() {
                public void windowClosing( WindowEvent e ) {
                    System.exit( 0 );
                }
            });

        pack();
        setVisible( true );
    }

    public void actionPerformed( ActionEvent e ) {
        display.repaint();
    }

    public void paint( Graphics g ) {
        String program = input.getText();

        lvm.execute( program, g );

    }

}