import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.awt.image.RenderedImage;
import java.awt.image.renderable.ParameterBlock;
import java.io.File;
import java.io.IOException;

import javax.media.jai.JAI;
import javax.media.jai.RenderedOp;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.JSlider;
import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;

import com.sun.media.jai.codec.FileSeekableStream;
import com.sun.media.jai.widget.DisplayJAI;

/*
 * file JAITest.java
 * @version 0.3
 * Created on 23.10.2006
 * Changed on 06.03.2022
 * @author Joerg Czeschla, javabeginners.de (c)2006 - 2022
 */

public class JAITest implements ChangeListener, ActionListener, ItemListener {

    // GUI Elemente
    private JSlider slider1, slider2, slider3;

    private JTextField bildTF, methodeTF, param1TF, param2TF, param3TF;

    private JLabel bildLabel, methodeLabel;

    private JPanel hauptPanel, werteTFPanel, sliderPanel, slider1Panel, slider2Panel, slider3Panel, elementePanel,
            buttonPanel, bildPanel, boxPanel, obenPanel;

    private JButton okButt, cancelButt;

    private JComboBox<String> comboBox;

    private DisplayJAI displayJAI;

    private RenderedImage renderedImage = null;

    // Eingabeverzeichnisname
    private String inputFile = "img/bild.jpg";

    // ComboBox-Starttext
    private String startText = "Bitte Methode w\u00E4hlen!";

    public JAITest() {
        initGUI();
    }

    private void initGUI() {
        // Slider
        slider1 = new JSlider(0, 0, 0);
        slider2 = new JSlider(0, 0, 0);
        slider3 = new JSlider(0, 0, 0);
        slider1.addChangeListener(this);
        slider2.addChangeListener(this);
        slider3.addChangeListener(this);

        // TextFelder
        bildTF = new JTextField(inputFile, 20);
        methodeTF = new JTextField("", 20);
        param1TF = new JTextField("0.00", 5);
        param1TF.addActionListener(this);
        param2TF = new JTextField("75.0", 5);
        param2TF.addActionListener(this);
        param3TF = new JTextField("0.00", 5);
        param3TF.addActionListener(this);

        // Label
        bildLabel = new JLabel("Bild: ");
        methodeLabel = new JLabel("Methode: ");

        // Buttons
        okButt = new JButton("ok");
        okButt.addActionListener(this);
        cancelButt = new JButton("cancel");
        cancelButt.addActionListener(this);

        // ComboBox
        comboBox = new JComboBox<String>();
        comboBox.addItemListener(this);
        comboBox.addItem(startText);
        comboBox.addItem("threshold");
        comboBox.addItem("rescale");
        comboBox.addItem("addConst");
        comboBox.addItem("scale");

        // Panels
        hauptPanel = new JPanel(new BorderLayout());
        werteTFPanel = new JPanel();
        sliderPanel = new JPanel(new BorderLayout());
        slider1Panel = new JPanel(new FlowLayout());
        slider2Panel = new JPanel(new FlowLayout());
        slider3Panel = new JPanel(new FlowLayout());
        bildPanel = new JPanel(new FlowLayout());
        boxPanel = new JPanel(new FlowLayout());
        obenPanel = new JPanel(new BorderLayout());
        elementePanel = new JPanel(new BorderLayout());
        buttonPanel = new JPanel();

        // Bilddisplay
        displayJAI = new DisplayJAI();

        // Slider und Textfelder in Grundstellung setzen
        setAllDisplays(true);

        // Layoutmanagement (der Einfachheit halber ohne GridBagLayout)
        slider1Panel.add(slider1);
        slider1Panel.add(param1TF);
        slider2Panel.add(slider2);
        slider2Panel.add(param2TF);
        slider3Panel.add(slider3);
        slider3Panel.add(param3TF);

        sliderPanel.add(slider1Panel, BorderLayout.NORTH);
        sliderPanel.add(slider2Panel, BorderLayout.CENTER);
        sliderPanel.add(slider3Panel, BorderLayout.SOUTH);

        bildPanel.add(bildLabel);
        bildPanel.add(bildTF);
        boxPanel.add(methodeLabel);
        boxPanel.add(comboBox);
        boxPanel.add(methodeTF);
        obenPanel.add(bildPanel, BorderLayout.NORTH);
        obenPanel.add(boxPanel, BorderLayout.SOUTH);

        buttonPanel.add(okButt);
        buttonPanel.add(cancelButt);

        elementePanel.add(sliderPanel, BorderLayout.NORTH);
        elementePanel.add(werteTFPanel, BorderLayout.CENTER);
        elementePanel.add(buttonPanel, BorderLayout.SOUTH);

        hauptPanel.add(obenPanel, BorderLayout.NORTH);
        hauptPanel.add(elementePanel, BorderLayout.SOUTH);

        // Bild initialisieren
        if (verifyFile(bildTF.getText())) {
            RenderedImage ri = readImg();

            if (ri != null) {
                setzeBild(ri);
            }
        }

        hauptPanel.add(displayJAI, BorderLayout.CENTER);

        JFrame frame = new JFrame("JAI Tool");
        frame.add(hauptPanel);
        frame.setSize(800, 800);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }

    /**
     * Pr&uuml;ft die Pfadangabe und erzeugt einen InputStream des Bildes
     * 
     * @return FileSeekableStream des zu bearbeitenden Bildes
     */
    private RenderedImage readImg() {
        FileSeekableStream image = null;
        try {
            if (verifyFile(bildTF.getText())) {
                image = new FileSeekableStream(bildTF.getText());
                // RenderedImage erstellen
                renderedImage = JAI.create("stream", image);
                return renderedImage;
            }
        } catch (IOException e) {
            System.out.println("Bitte den Pfad zu einem Bild angeben!");
            setAllDisplays(true);
            return null;
        }
        return null;
    }

    /**
     * Pr&uuml;ft die Pfadangabe auf Existenz und Lesbarkeit
     */
    private boolean verifyFile(String pfad) {
        File f = new File(pfad);
        if (f.isFile() && f.canRead()) {
            return true;
        }
        return false;
    }

    /**
     * positioniert das Bild auf dem Display
     * 
     * @param ri
     * @return
     */
    private void setzeBild(RenderedImage ri) {
        int breite = ri.getWidth(), hoehe = ri.getHeight();
        Dimension dim = new Dimension((800 - breite) / 2, (600 - hoehe) / 2);
        displayJAI.set(ri, (int) dim.getWidth(), (int) dim.getHeight());
    }

    /**
     * Factory-Methode zum methodenabh&auml;ngigen Setzen der Slider
     * 
     * @param slider
     * @param visible sichtbar wenn true
     * @param min     Minimalwert
     * @param max     Maximalwert
     * @param val     Ausgangsposition des Sliders
     */
    private void setSliderValue(JSlider slider, JTextField field, boolean visible, int min, int max, int val) {
        slider.setPreferredSize(new Dimension(300, 25));
        slider.setVisible(visible);
        slider.setMinimum(min);
        slider.setMaximum(max);
        slider.setValue(val);
        field.setVisible(visible);
        field.setText(new Double(val / 100).toString());
    }

    /**
     * Setzt alle Slider und Werte-Textfelder auf Grundstellung
     * 
     * @param visible
     */
    private void setAllDisplays(boolean visible) {
        setSliderValue(slider1, param1TF, visible, 0, 0, 0);
        setSliderValue(slider2, param2TF, visible, 0, 0, 0);
        setSliderValue(slider3, param3TF, visible, 0, 0, 0);
    }

    /**
     * Passt die Werte-Textfelder und Slider-Positionen aneinander an
     * 
     * @param ce
     */
    private void setTFText(ChangeEvent ce) {
        if (ce.getSource() == slider1) {
            param1TF.setText(new Double((double) slider1.getValue() / 100).toString());
        }
        if (ce.getSource() == slider2) {
            param2TF.setText(new Double((double) slider2.getValue() / 100).toString());
        }
        if (ce.getSource() == slider3) {
            param3TF.setText(new Double((double) slider3.getValue() / 100).toString());
        }
    }

    /**
     * Hauptmethode zur Bildbearbeitung
     * 
     * @param im      Zu bearbeitendes RenderedImage
     * @param methode String der anzuwendenden Methode
     * @param wert1   Wert1
     * @param wert2   Wert2
     * @param wert3   Wert3
     */
    private void render(RenderedImage im, String methode, String wert1, String wert2, String wert3) {
        if (renderedImage != null) {
            im = renderedImage;
            System.out.println("renderedImahe ungleich null!");
        }
        System.out.println(methode + " gew\u00E4hlt...");
        ParameterBlock pb = new ParameterBlock();
        pb.addSource(im);
        float f = 1.0F;
        double[] d1 = new double[3];
        double[] d2 = new double[3];
        double[] d3 = new double[3];

        if (methode.equals("") || methode.equals(startText)) {
            return;

        } else if (methode.equals("addConst")) {
            d1[0] = new Double(wert1).doubleValue();
            d1[1] = new Double(wert2).doubleValue();
            d1[2] = new Double(wert3).doubleValue();
            pb.add(d1);

        } else if (methode.equals("rescale")) {
            d1[0] = new Double(wert1).doubleValue();
            d1[1] = new Double(wert1).doubleValue();
            d1[2] = new Double(wert1).doubleValue();
            d2[0] = new Double(wert2).doubleValue();
            d2[1] = new Double(wert2).doubleValue();
            d2[2] = new Double(wert2).doubleValue();
            pb.add(d1);
            pb.add(d2);

        } else if (methode.equals("scale")) {
            f = new Float(wert1).floatValue();

            pb.add(f);
            pb.add(f);
            pb.add(0.0F);
            pb.add(0.0F);
            RenderedOp op = JAI.create(methode, pb);
            int breite = op.getWidth();
            int hoehe = op.getHeight();
            System.out.println("Breite: " + breite);
            System.out.println("Hoehe: " + hoehe);
            System.out.println("Berechnete Breite: " + (displayJAI.getWidth() - breite) / 2.0F);
            System.out.println("Berechnete Hoehe: " + (displayJAI.getHeight() - hoehe) / 2.0F);
            displayJAI.setOrigin((displayJAI.getWidth() - breite) / 2, 0);

        } else {
            d1[0] = new Double(wert1).doubleValue();
            d2[0] = new Double(wert2).doubleValue();
            d3[0] = new Double(wert3).doubleValue();
            if (d1[0] >= d2[0])
                d1[0] = d2[0];
            pb.add(d1);

            if (d2[0] <= d1[0])
                d2[0] = d1[0];
            pb.add(d2);

            pb.add(d3);
        }

        // Bild bearbeiten
        RenderedOp op = JAI.create(methode, pb);
        // bearbeitetes Bild registrieren
        renderedImage = op;
        // Bild darstellen
        displayJAI.set(op);
    }

    /**
     * Aufruf bei Methodenauswahl der Combobox
     */
    public void stateChanged(ChangeEvent ce) {

        setTFText(ce);

        RenderedImage ri = readImg();

        if (ri == null) {
            return;
        }

        render(ri, (String) comboBox.getSelectedItem(), param1TF.getText(), param2TF.getText(), param3TF.getText());
    }

    /**
     * Aufgerufen durch Textfelder und Buttons
     */
    public void actionPerformed(ActionEvent e) {
        if (e.getSource() == cancelButt) {
            System.exit(0);
        }
        if (e.getSource() == okButt) {
            RenderedImage ri = readImg();

            if (ri == null) {
                return;
            }
            String methode = (String) comboBox.getSelectedItem();

            render(ri, methode, param1TF.getText(), param2TF.getText(), param3TF.getText());
        }
        if (e.getSource() == param1TF) {
            slider1.setValue((int) (new Double(param1TF.getText()).doubleValue() * 100));
        }
        if (e.getSource() == param2TF) {
            slider2.setValue((int) (new Double(param2TF.getText()).doubleValue() * 100));
        }
        if (e.getSource() == param3TF) {
            slider3.setValue((int) (new Double(param3TF.getText()).doubleValue() * 100));
        }
    }

    /**
     * Sliderwerte je nach Auswahl einer Bearbeitungsmethode setzen und bei Bewegung
     * anpassen
     */
    public void itemStateChanged(ItemEvent e) {
        if (comboBox.getSelectedItem().equals(startText)) {
            setAllDisplays(true);
        }
        if (comboBox.getSelectedItem().equals("rescale")) {
            methodeTF.setText("Kontrast");
            setSliderValue(slider1, param1TF, true, 0, 400, 100);
            setSliderValue(slider2, param2TF, true, -25500, 25500, 0);
            setSliderValue(slider3, param3TF, false, 0, 0, 0);
        }
        if (comboBox.getSelectedItem().equals("threshold")) {
            methodeTF.setText("bin\u00E4rer Kontrast");
            setSliderValue(slider1, param1TF, true, 0, 500, 0);
            setSliderValue(slider2, param2TF, true, 5000, 10000, 7500);
            setSliderValue(slider3, param3TF, true, 0, 10000, 0);
        }
        if (comboBox.getSelectedItem().equals("addConst")) {
            methodeTF.setText("Helligkeit");
            setSliderValue(slider1, param1TF, true, -25000, 25000, 0);
            setSliderValue(slider2, param2TF, true, -25000, 25000, 0);
            setSliderValue(slider3, param3TF, true, -25000, 25000, 0);
        }
        if (comboBox.getSelectedItem().equals("scale")) {
            methodeTF.setText("Skalieren");
            setSliderValue(slider1, param1TF, true, 10, 190, 100);
            setSliderValue(slider2, param2TF, false, 0, 0, 0);
            setSliderValue(slider3, param3TF, false, 0, 0, 0);
        }
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(() ->  new JAITest());
    }
}