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

/** TGA file animation viewer
 * Master's Thesis, Univ of Colo, 2001
 * Reads a set of TGA files frame1, frame2...
 * and displays them rapidly for animation
 * @author: Phil Gage
 */
public class ShowMovie extends Panel {

    /** Total number of frames */
    int frames = 0;

    /** Current frame number */
    int frame = 0;

    /** Initialization flag */
    boolean init = false;

    /** Maximum number of image frames */
    final int MAXFRAMES = 100;

    /** Image pixmap array for graphics */
    Image img[] = new Image [MAXFRAMES];

    /** Graphic window to display animation */
    public static Frame f;

    /** Delay in msec to slow animation */
    static int delay = 0;

    /**
     * Method loadImages reads the TGA files into the image array.
     */
    void loadImages () {
        String filename;
        boolean success;
        FrameBuffer fb = new FrameBuffer ();
        for (int i=0; i<=MAXFRAMES; i++) {
            filename = "frame" + i + ".tga";
            success = fb.loadtga (filename);
            if (!success)
                break;
            if (i == MAXFRAMES) {
                System.out.println ("Frame limit exceeded: " + i);
                break;
            }
            img[i] = fb.getImage (f);
            frames++;
            System.out.println (filename);
        }
        if (frames == 0) {
            System.out.println ("No image files found");
            System.exit (0);
        }
        System.out.println (frames + " frames loaded");
        // Resize window to image size
        f.setSize (fb.width,fb.height);
    }

    /**
     * Method paint redraws window each time window is exposed.
     * This version saves graphics in images for fast redraw.
     * @param g  graphics object
     */
    public void paint (Graphics g) {
//        System.out.println ("in paint");
        // Initialize image once
        if (!init) {
            init = true;
            loadImages ();
        }
        // Refresh image
        g.drawImage (img[frame], 0, 0, getWidth(), getHeight(), this);
        repaint();
    }

    /**
     * Method update redraws window each time after repaint.
     * This overrides default method that erases window and.
     * causes an annoying flicker when white background shows.
     * @param g  graphics object
     */
    public void update (Graphics g) {
       if (++frame >= frames)
           frame=0;
      g.drawImage (img[frame], 0, 0, getWidth(), getHeight(), this);
       if (delay > 0) {
           try {
               Thread.sleep(delay);  //delay
           } catch(InterruptedException e) {}
       }
       if (frames > 1)
           repaint();
    }

    /**
     * Main program for command line application.
     * Adds window close event handler.
     * Creates panel in frame and displays image.
     * @param argv  command line argument strings
     */
    public static void main (String[] argv) {
        System.out.println ("TGA Animation viewer by Phil Gage");
        System.out.println ("Master's Thesis, Univ of Colo, 2002");
        System.out.println ("Usage: java ShowMovie [delay]");
        System.out.println ("Optional delay in msec");
        System.out.println ("Reads files frame0.tga, frame1.tga...");

        // Get optional delay between frames
        if (argv.length > 0) {
            try {
               delay = new Integer(argv[0].trim()).intValue();
            } catch(Exception e) {
                System.out.println ("Invalid delay");
                System.exit (0);
            }
        }

        // Create frame and app
        f = new Frame ("Java Ray Tracer Animation");
        ShowMovie app = new ShowMovie ();

        // Add window close event handler
        f.addWindowListener (new WindowAdapter () {
            public void windowClosing (WindowEvent e) {
                System.exit (0);
            }
        });

        // Put panel in frame
        f.add ("Center", app);
        f.setSize (320,200);
        f.show ();
    }
}