/* 
 * A simple proto of an image sorting tool, SJ 051107
 *
 * Takes image filenames from command line
 * for each image, SPACE does nothing (but show next image),
 * letters a-c (currently, TODO) copy the image a directory a, b, c
 * q quits
 *
 * Demonstrates image loading and drawing, SwingWorker threads, KeyListener
 */

/* TODO
 * directory names from somewhere
 * 
 * close files, dispose imagereaders
 * no cycle through images
 * make copy more portable (now used mv)
 * show file name more clearly
 * better scaling to display (in background thread)
 * revert to previous image (and optinally undo previous copy)
 * scaling/re-encoding saved images (in background)
 * mouse action
 * options from menus/checkbuttons
 * FileSelector to open a new directory
 * progress bar
 * ...
 */

import java.awt.*;
import java.awt.event.*;
import java.awt.image.*;
import java.io.*;
import javax.imageio.ImageIO;
import javax.swing.*;
import java.util.Set;
import java.util.HashSet;

public class ImageSelect
    extends JFrame
    implements KeyListener
{
    static String[] files;
    static int next = -1;
    Set<Character> oDirectories;
    // TODO: get from somewhere
    static char [] dirs = {'a', 'b', 'c'};
    Container cPane;
    ImageReader currIR, nextIR;
    ImagePanel IP;

    public ImageSelect() {
        oDirectories = new HashSet<Character>();
        for (int i = 0; i < dirs.length; i++)
            oDirectories.add(dirs[i]);
        draw();
    }

    private void draw() {
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        // image displaying panel
        IP = new ImagePanel();
        IP.setPreferredSize(new Dimension(400, 300));

        this.add(IP);
        this.addKeyListener(this);

        this.pack();
        this.setVisible(true);

        // start loading first image
        nextIR = getNextIR();
        if (nextIR == null) { // no images
            this.dispose();
            return;
        }
        

        // display first image
        next();
    }


    /*
     * display next image
     */
    private void next() {
        currIR = nextIR;        // previously loaded image
        nextIR = getNextIR();   // start loading a new image
        showImage(currIR);      // show image
    }

    /*
     * start new image reader for next filename
     */
    private ImageReader getNextIR() {
        if (files.length == 0)
            return null;
        next = (next + 1) % files.length;

        ImageReader IR = new ImageReader(files[next], this.getWidth(), this.getHeight());
        IR.execute();
        return IR;
    }

    /*
     * show image of an ImageReader
     */
    private void showImage(ImageReader IR) {
        IP.setImage(IR);
        IP.repaint();
    }

    // Key listener
    public void keyTyped(KeyEvent e) {
        if (e.getKeyChar() == ' ')
            next();
        else if (e.getKeyChar() == 'q')
            this.dispose();
        else if (oDirectories.contains(e.getKeyChar())) {
            currIR.copyToDir("" + e.getKeyChar());
            next();
        }
    }

    public void keyPressed(KeyEvent e) {
    }

    public void keyReleased(KeyEvent e) {
    }

        
    public static void main(String[] args) {
        //Schedule a job for the event-dispatching thread:
        //creating and showing this application's GUI.
        files = args;
        javax.swing.SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                ImageSelect cgui = new ImageSelect();
            }
        });
    } // main()

    /*
     * Image viewing panel
     */
    public class ImagePanel extends JPanel {
        BufferedImage bi;

        /*
         * get image from ImageReader
         */
        public void setImage(ImageReader IR) {
            try {
                bi = IR.get();
            } catch (Exception e) { System.err.println("ImagePanel.setImage: " +e); }
        }

        /*
         * show image scaled to this panel
         */
        public void paintComponent(Graphics g) {
            super.paintComponent(g);
            Graphics2D g2 = (Graphics2D)g;
            // g2.drawImage(bi, 0, 0, this.getWidth(), this.getHeight(), null);
            g2.drawImage(bi, 0, 0, null);
        }
    } // class ImagePanel


    /*
     * background thread to load and decode an image from file
     */
    public class ImageReader extends SwingWorker<BufferedImage, Void> {
        String fn = null;
        int w, h;

        public ImageReader(String fileName, int width, int heigth) {
            fn = fileName;
            w = width;
            h = heigth;
        }
        /*
         * loads an image
         */
        @Override
        public BufferedImage doInBackground() {
            BufferedImage bi, bi2;
            try {

                // read image
                bi = ImageIO.read(new File(fn));

                // scale image
                // Image im = bi.getScaledInstance(w, h, Image.SCALE_FAST);
                Image im = bi.getScaledInstance(w, h, Image.SCALE_SMOOTH);
                bi2 = new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
                Graphics2D bi2g = bi2.createGraphics();
                bi2g.drawImage(im, 0, 0, null);
                bi2g.drawString(fn, 10, 10);    // add file name
                return bi2;

            } catch (Exception e) {
                return null;
            }
        }

        public void copyToDir(String dirName) {
            // TODO: not portable
            try {
                Runtime.getRuntime().exec("cp " + fn + " " + dirName);
            } catch (Exception e) {}
        }

    } // class ImageReader

} // class ImageSelect