import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.GridLayout;
import java.text.NumberFormat;
import java.util.*;

public class MyCypherMachine extends JFrame implements DocumentListener, ActionListener, KeyListener {
	
	private JButton commit;
	private JPanel panel;
	private JLabel texteRotation = new JLabel("Indiquer le nombre de rotation : ");
	private JFormattedTextField fieldRotation;
	private JLabel texteSens = new JLabel("Indiquer le sens de rotation : ");
	private JFormattedTextField fieldSens;
	private JLabel chiffrement = new JLabel("Zone du texte à crypter/decrypter : ");
	private JTextArea zoneTexteChiffre;
	private JLabel traduction = new JLabel("Texte decrypté/crypté : ");
	private JTextArea zoneTexteTraduc;
	private JLabel texteChoix = new JLabel("Choix d'utilisation : ");
	private ButtonGroup boutonChoix = new ButtonGroup();
	private JRadioButton cypher = new JRadioButton("Cryptage", true);
	private JRadioButton decypher = new JRadioButton("Decryptage", false);
	
	private NumberFormat numberFormat;
	private int nbreRotation;
	private int sensRotation;
	
	public MyCypherMachine() {
		super("Encrypteur/Décrypteur");
		numberFormat = NumberFormat.getNumberInstance();
		initComponents();
	}
	
	private void initComponents() {
		setResizable(false);
		setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
		
		zoneTexteChiffre = new JTextArea();
		zoneTexteTraduc = new JTextArea();
		zoneTexteChiffre.getDocument().addDocumentListener(this);
		zoneTexteChiffre.addKeyListener(this);
		JScrollPane scrollChiffre = new JScrollPane(zoneTexteChiffre);
		JScrollPane scrollTraduc = new JScrollPane(zoneTexteTraduc);
		
		zoneTexteChiffre.setEditable(false);
		zoneTexteChiffre.setBackground(Color.gray);
		zoneTexteTraduc.setEditable(false);
		zoneTexteTraduc.setBackground(Color.gray);
		
		commit = new JButton("Commit !!");
		commit.addActionListener(this);
		
		fieldRotation = new JFormattedTextField(numberFormat);
		fieldSens = new JFormattedTextField(numberFormat);
		
		boutonChoix.add(cypher);
		boutonChoix.add(decypher);
		
		panel = new JPanel(new GridLayout(6, 2, 3, 2));
		JPanel radioPanel = new JPanel(new GridLayout(0, 1));
		radioPanel.add(cypher);
		radioPanel.add(decypher);
		
		panel.add(texteChoix);
		panel.add(radioPanel);
		panel.add(texteRotation);
		panel.add(fieldRotation);
		panel.add(texteSens);
		panel.add(fieldSens);
		panel.add(new JLabel(""));
		panel.add(commit);
		panel.add(chiffrement);
		panel.add(scrollChiffre);
		panel.add(traduction);
		panel.add(scrollTraduc);
		
		this.setContentPane(panel);
		
		pack();
		setLocationRelativeTo(null);
	}
	
	public void changedUpdate(DocumentEvent ev) {}
    
    public void removeUpdate(DocumentEvent ev) {
		if (ev.getLength() != 1) {
			zoneTexteTraduc.setText("");
            return;
        }
		
		int pos = ev.getOffset();
		String content = null;
		try {
			content = zoneTexteTraduc.getText(0, pos + 1);
		}
		catch (BadLocationException e) {
            e.printStackTrace();
        }
		zoneTexteTraduc.setText(new String(content.substring(0, pos)));
    }
    
    public void insertUpdate(DocumentEvent ev) {
		if (ev.getLength() != 1) {
            return;
        }
        
        int pos = ev.getOffset();
        String content = null;
        try {
            content = zoneTexteChiffre.getText(0, pos + 1);
        } catch (BadLocationException e) {
            e.printStackTrace();
        }
		int caractere = (int) content.charAt(pos);
		String retour = cypherText(caractere);
		if(decypher.isSelected())
			sensRotation = -sensRotation;
		zoneTexteTraduc.append(retour);
		if (decypher.isSelected())
			sensRotation = -sensRotation;
	}
	
	public String cypherText(int caractere) {
		if(caractere >= (int) 'a' && caractere <= (int) 'z')
			if(sensRotation < 0)
				if(caractere < ((int) 'a') + nbreRotation)
					caractere = caractere + 26 - nbreRotation;
				else
					caractere -= nbreRotation;
			else
				if(caractere > ((int) 'z') - nbreRotation)
					caractere = caractere - 26 + nbreRotation;
				else
					caractere += nbreRotation;
		char[] tabChar = {(char) caractere};
		return new String(tabChar);
	}
	
	public void actionPerformed(ActionEvent e) {
		if (!fieldRotation.getText().equals("") && !fieldSens.getText().equals("")) {
			zoneTexteChiffre.setEditable(true);
			zoneTexteChiffre.setBackground(Color.white);
			zoneTexteTraduc.setEditable(true);
			zoneTexteTraduc.setBackground(Color.white);
		}
		
		nbreRotation = Integer.parseInt(fieldRotation.getText());
		sensRotation = Integer.parseInt(fieldSens.getText());
	}
	
	public void keyPressed(KeyEvent e) {}
	public void keyReleased(KeyEvent e) {}
	public void keyTyped(KeyEvent e)  {
		int key = (int) e.getKeyChar();
		if(e.getKeyModifiersText(e.getModifiers()).equals("Ctrl") && key == 22) {
			if(decypher.isSelected())
				sensRotation = -sensRotation;
			String texte = zoneTexteChiffre.getText();
			
			char[] tabChar = texte.toCharArray();
			String ret = "";
			for(int i = 0; i < tabChar.length; i++)
				ret = ret + cypherText(tabChar[i]);
			
			zoneTexteTraduc.setText(ret);
			if (decypher.isSelected())
				sensRotation = -sensRotation;
		}
	}
	
	
	public static void main(String args[]) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                new MyCypherMachine().setVisible(true);
            }
        });
    }
}