package javacodebook.media.graphic.brightness;

import java.awt.*;
import java.io.*;
import javax.swing.*;

/** Ein einfaches Programm zur Bildanzeige und Manipulation der Helligkeit.
 */
public class ImageFrame extends javax.swing.JFrame {

    private javax.swing.JLabel jLabel1;
    private javax.swing.JScrollPane scrollPane;
    private javax.swing.JLabel jLabel2;
    private javax.swing.JPanel jPanel2;
    private javax.swing.JFileChooser fileChooser;
    private javax.swing.JSlider jSlider1;
    private javax.swing.JMenuItem jMenuItem1;
    private javax.swing.JPanel jPanel1;
    private javax.swing.JMenu jMenu1;
    private javax.swing.JMenuBar jMenuBar1;
    private ImagePanel imagePanel;

    public ImageFrame() {
        initComponents();
    }

    private void initComponents() {
        fileChooser = new javax.swing.JFileChooser();
        jPanel1 = new javax.swing.JPanel();
        jSlider1 = new javax.swing.JSlider();
        jLabel1 = new javax.swing.JLabel();
        jLabel2 = new javax.swing.JLabel();
        jPanel2 = new javax.swing.JPanel();
        scrollPane = new javax.swing.JScrollPane();
        jMenuBar1 = new javax.swing.JMenuBar();
        jMenu1 = new javax.swing.JMenu();
        jMenuItem1 = new javax.swing.JMenuItem();

        addWindowListener(new java.awt.event.WindowAdapter() {
            public void windowClosing(java.awt.event.WindowEvent evt) {
                exitForm(evt);
            }
        });

        jPanel1.setLayout(new java.awt.BorderLayout());

        jSlider1.setMaximum(200);
        jSlider1.setMinimum(1);
        jSlider1.setOrientation(javax.swing.JSlider.VERTICAL);
        jSlider1.setPaintLabels(true);
        jSlider1.setValue(100);
        jSlider1.setEnabled(false);
        jSlider1.addChangeListener(new javax.swing.event.ChangeListener() {
            public void stateChanged(javax.swing.event.ChangeEvent evt) {
                brightnessChanged(evt);
            }
        });

        jPanel1.add(jSlider1, java.awt.BorderLayout.CENTER);

        jLabel1.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
        jLabel1.setText("Heller");
        jPanel1.add(jLabel1, java.awt.BorderLayout.NORTH);

        jLabel2.setHorizontalAlignment(javax.swing.SwingConstants.CENTER);
        jLabel2.setText("Dunkler");
        jPanel1.add(jLabel2, java.awt.BorderLayout.SOUTH);

        getContentPane().add(jPanel1, java.awt.BorderLayout.EAST);

        jPanel2.setLayout(new java.awt.BorderLayout());

        jPanel2.add(scrollPane, java.awt.BorderLayout.CENTER);

        getContentPane().add(jPanel2, java.awt.BorderLayout.CENTER);

        jMenu1.setText("Datei");
        jMenuItem1.setText("\u00d6ffnen");
        jMenuItem1.addActionListener(new java.awt.event.ActionListener() {
            public void actionPerformed(java.awt.event.ActionEvent evt) {
                openFile(evt);
            }
        });

        jMenu1.add(jMenuItem1);

        jMenuBar1.add(jMenu1);

        setJMenuBar(jMenuBar1);

        pack();
    }

    /** Diese Methode ist als Listener beim Schieberegler registriert
     *  und erfasst Änderungen. Diese werden über den Massstab umgerechnet und
     *  als Alpha-Wert an das ImagePanel weitergegeben.
     */
    private void brightnessChanged(javax.swing.event.ChangeEvent evt) {//GEN-FIRST:event_brightnessChanged
        float value = jSlider1.getValue();
        value = value/100;
        //Da der Wert 2 noch keine Starke Erhöhung der Helligkeit bedeutet,
        //müssen wir ein Streckung vornehmen.
        if(jSlider1.getValue() > 100)
            value = (float)Math.pow((double)value, 1.5*value);
        imagePanel.setBrightness(value);
        imagePanel.repaint();
    }

    /** Grafikdatei öffnen und anzeigen. Dabei wird der Schieberegler wieder
     *  auf den Ausgangswert gesetzt.
     */
    private void openFile(java.awt.event.ActionEvent evt) {//GEN-FIRST:event_openFile
        int pressedButton = fileChooser.showOpenDialog(this);
        if(pressedButton == JFileChooser.APPROVE_OPTION) {
            File f = fileChooser.getSelectedFile();
            ImageIcon icon = new ImageIcon(f.getAbsolutePath());
            if(imagePanel == null) {
                imagePanel = new ImagePanel();
                imagePanel.setImage(icon.getImage());
                scrollPane.getViewport().setView(imagePanel);
                jSlider1.setEnabled(true);
            }
            else
                imagePanel.setImage(icon.getImage());
            jSlider1.setValue(100);
            this.repaint();
        }
    }

    private void exitForm(java.awt.event.WindowEvent evt) {//GEN-FIRST:event_exitForm
        System.exit(0);
    }

    public static void main(String args[]) {
        ImageFrame frame = new ImageFrame();
        frame.setSize(640, 480);
        frame.show();
    }


}