/*
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 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
package zad6;

/**
 *
 * @author troll
 */
/*
 * To change this license header, choose License Headers in Project Properties.
 * To change this template file, choose Tools | Templates
 * and open the template in the editor.
 */
import static zad6.Zad6.jb;
import static zad6.Zad6.jp;
import java.awt.Color;
import java.awt.Cursor;
import java.awt.Dimension;
import java.awt.FlowLayout;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Image;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import java.awt.event.MouseMotionListener;
import java.awt.geom.Ellipse2D;
import java.awt.geom.Rectangle2D;
import java.awt.image.BufferedImage;
import java.util.ArrayList;
import javax.swing.JButton;
import javax.swing.JFileChooser;
import javax.swing.JFrame;
import javax.swing.JPanel;

/**
 *
 * @author Pawel
 */
class MyPanel extends JPanel implements MouseListener, MouseMotionListener {

    static ArrayList<Integer> xPoints, yPoints, x, y, pointsListX, pointsListY;
    static ArrayList<Rectangle2D.Double> shapes;
    int startX = 0, startY = 0, endX, endY;
    int index = 0, pos = -1;
    boolean needClear = false;
    double step = 0.01;

    public static double countNewton(double n, int k) {
        double Wynik = 1;       // Deklaracja zmiennych
        int i;

        for (i = 1; i <= k; i++) // Od 1 do k wykonujemy :
        {
            Wynik = Wynik * (n - i + 1) / i;      // Obliczanie ze wzoru iteracyjnego
        }

        return Wynik;   // Zwróć Wynik
    }

    public void bezierFunc(int degree, int pointsCounter) {
        for (double p = 0; p <= 1; p += step) {
            double xPoint = 0;
            for (int i = 0; i <= degree; ++i) {
                double Newton = countNewton(degree, i); //Obliczamy wartość współczynnika Newtona
                double ti = Math.pow(p, i); //Pierwszy element wzoru t do potęgi i-tej
                double lti = Math.pow((1 - p), (degree - i)); //Drugi element wzoru (1-t) do potęgi (ni)
                xPoint = xPoint + (Newton * ti * lti * x.get(i)); //Tworzymy składową x-ową
            }
            if (xPoint > x.get(pointsCounter - 1)) {
                break;
            }

            xPoints.add((int) xPoint);
            double yPoint = 0;
            for (int i = 0; i <= degree; ++i) {
                double yNewton = countNewton(degree, i);
                double yti = Math.pow(p, i);
                double ylti = Math.pow((1 - p), (degree - i));
                yPoint = yPoint + (yNewton * yti * ylti * y.get(i));
            }
            yPoints.add((int) yPoint);
        }
    }

    public MyPanel() {
        this.addMouseListener(this);
        this.addMouseMotionListener(this);
        pointsListX = new ArrayList<>();
        pointsListY = new ArrayList<>();
        shapes = new ArrayList<>();
        xPoints = new ArrayList<>();
        yPoints = new ArrayList<>();
        x = new ArrayList<>();
        y = new ArrayList<>();
        jb.addActionListener(new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                needClear = true;
                try {
                    bezierFunc(x.size() - 1, x.size());
                } catch (ArrayIndexOutOfBoundsException abc) {
                }
                repaint();
            }
        });
    }

    @Override
    public void paintComponent(Graphics g) {
        super.paintComponent(g);
        Graphics2D g2 = (Graphics2D) g;
        if (pointsListX.size() > 0) {
            for (int a = 0; a < shapes.size(); a++) {
                g2.fill(shapes.get(a));
            }
        }
        int[] xs, ys;
        xs = new int[xPoints.size()];
        ys = new int[yPoints.size()];
        for (int a = 0; a < xPoints.size(); a++) {
            xs[a] = xPoints.get(a);
            ys[a] = yPoints.get(a);
        }
        g.drawPolyline(xs, ys, xPoints.size());
        g.dispose();
    }

    @Override
    public void mouseClicked(MouseEvent e) {
    }

    @Override
    public void mousePressed(MouseEvent e) {
        boolean contains = false;

        for (int i = 0; i < shapes.size(); i++) {
            if (shapes.get(i).intersects(e.getX(), e.getY(), 5, 5)) {
                contains = true;
                pos = i;
                return;
            }
        }
        if (!contains) {
            if (needClear) {
                xPoints.clear();
                yPoints.clear();
                pointsListX.clear();
                pointsListY.clear();
                x.clear();
                y.clear();
                shapes.clear();
                needClear = false;
            }
            x.add(e.getX());
            y.add(e.getY());

            pointsListX.add(e.getX());
            pointsListY.add(e.getY());
            Rectangle2D.Double rec = new Rectangle2D.Double(e.getX(), e.getY(), 10, 10);
            shapes.add(rec);

            repaint();
        }
    }

    @Override
    public void mouseReleased(MouseEvent e) {
        pos = -1;
    }

    @Override
    public void mouseEntered(MouseEvent e) {
        setCursor(new Cursor(Cursor.CROSSHAIR_CURSOR));
    }

    @Override
    public void mouseExited(MouseEvent e) {
    }

    @Override
    public void mouseDragged(MouseEvent e) {
        if (pos == -1) {
            return;
        }
        shapes.get(pos).setFrame(e.getX(), e.getY(), shapes.get(pos).getWidth(), shapes.get(pos).getHeight());
        x.set(pos, e.getX());
        y.set(pos, e.getY());
        try {
            xPoints.clear();
            yPoints.clear();
            bezierFunc(x.size() - 1, x.size());
        } catch (ArrayIndexOutOfBoundsException abc) {
        }
        repaint();
    }

    @Override
    public void mouseMoved(MouseEvent e) {
    }

}

public class Zad6 {

    public static int value;
    static JButton jb;
    JFrame jf;
    static JPanel jp, container, container2;
    JFileChooser fc;
    BufferedImage bf, bf2;
    Image img;

    public Zad6() {
        value = 0;
        fc = new JFileChooser();
        jf = new JFrame("Bezier");
        jf.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        jf.setSize(new Dimension(800, 600));
        jb = new JButton("Draw!");
        jp = new JPanel();
        container = new MyPanel();
        container.setPreferredSize(new Dimension(500, 500));
        container.setBackground(Color.white);
        jp.setPreferredSize(new Dimension(800, 600));
        jp.setLayout(new FlowLayout());
        jf.add(jp);
        jp.add(container);
        jp.add(jb);
        jf.pack();
        jf.setVisible(true);
    }

    /**
     * @param args the command line arguments
     */
    public static void main(String[] args) {
        new Zad6();
    }

}