import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
import javax.swing.event.ChangeEvent;
import javax.swing.event.ChangeListener;

class FourierPanel extends JPanel implements ActionListener, ChangeListener {
  /**
	 *
	 */
	private static final long serialVersionUID = 1L;
private TraceV7 trace = new TraceV7(this);
  private JSlider sAmp = new JSlider(1, 50);
  private JSlider tfFreq = new JSlider(1, 10);
  private JSlider sHarm = new JSlider(1, 50);
  private JComboBox<String> chForm = new JComboBox<String>();
  private JButton btBerechne = new JButton("Berechne");
  private PlotPanel plotPanel = new PlotPanel();
  private double[] signal = {};

  private static final int TRAPEZ = 0, DREIECK = 1, SAWTOOTH = 2, RECHTECK = 3, PULSE = 4;

  /**
   * <pre>
   * - Baut GUI
   * - Registriert Listener
   * </pre>
   */
  public FourierPanel() {
    trace.constructorCall();
    setLayout(null);

    add(new Label("Amplitude:")).setBounds(20, 20, 60, 20);
    add(sAmp).setBounds(100, 20, 100, 20);
    sAmp.addChangeListener(this);

    add(new Label("Frequenz:")).setBounds(500, 20, 60, 20);
    add(tfFreq).setBounds(560, 20, 100, 20);
    tfFreq.addChangeListener(this);
    sHarm.addChangeListener(this);
    add(new Label("Form:")).setBounds(20, 50, 60, 20);
    add(chForm).setBounds(100, 50, 100, 20);
    add(new Label("Harmonics:")).setBounds(490, 50, 70, 20);
    add(sHarm).setBounds(560, 50, 100, 20);

    add(btBerechne).setBounds(10, 650, 680, 20);
    btBerechne.addActionListener(this);

    chForm.addItem("Trapez");
    chForm.addItem("Dreieck");
    chForm.addItem("Sawtooth");
    chForm.addItem("Rechteck");
    chForm.addItem("Pulse");

    add(plotPanel).setBounds(25, 100, 695, 620);
  }

  /**
   * <pre>
   * - Liest Information aus GUI aus und legt sie in entsprechenden lokalen Var. ab.
   * - Verzweigung chForm.getSelectedIndex():
   *   - Fall 0:
   *     - signal gleich berechneRechteck() mit entsprechenden Parametern berechnen.
   *   - Fall 1:
   *     - signal gleich berechneDreieck() mit entsprechenden Parametern berechnen.
   *   - Fall 2:
   *     - signal gleich berechneSaegezahn() mit entsprechenden Parametern berechnen.
   *   - Fall 3:
   *     - signal gleich berechneTrapez() mit entsprechenden Parametern berechnen.
   *   - Fall 4:
   *     - signal gleich berechnePulse() mit entsprechenden Parametern berechnen.
   * - Setzt Signal des PlotPanels mittels setSignal().
   * - Löst Neuzeichnen aus.
   * </pre>
   */
  @Override
  public void actionPerformed(ActionEvent e) {
    trace.eventCall();
    int N = 620; // Anzahl Punkte auf der x Achse

    if(e.getSource()==btBerechne) {

    //double ampli = Double.parseDouble(tfAmp.getText());
    int ampli = sAmp.getValue();
    int frequi = tfFreq.getValue();
    int harmoni = sHarm.getValue();

    switch (chForm.getSelectedIndex()) {
	case RECHTECK:
		signal = berechneRechteck(ampli, frequi, harmoni, N);
		break;

	case DREIECK:
		signal = berechneDreieck(ampli, frequi, harmoni, N);
		break;

	case SAWTOOTH:
		signal = berechneSaegezahn(ampli, frequi, harmoni, N);
		break;

	case TRAPEZ:
		signal = berechneTrapez(ampli, frequi, harmoni, N);
		break;

	case PULSE:
		signal = berechnePulse(ampli, frequi, harmoni, N);
		break;
	}
    plotPanel.setSignal(signal);
    plotPanel.repaint();
    }
  }

  private double[] berechnePulse(double amp, double freq, int nHarm, int N) {
    trace.methodeCall();
    double[] x = new double[N];

    double omega = (Math.PI * 2.0 * freq)/620;

    for (int harms = 1; harms<= nHarm; harms++) {
    for (int n = 0; n< N; n++) {
    	x[n] += ((amp*2) * Math.sin(n*omega*harms));
    }
    }

    return x;
  }

  private double[] berechneTrapez(double amp, double freq, int nHarm, int N) {
    trace.methodeCall();
    double[] x = new double[N];

    double beta = Math.PI / 3.0;

    for (int n = 0; n < N; n++) {
    for ( int k = 1; k <= nHarm+1; k++) {
    x[n] += (8*amp/(Math.PI*beta))
    * Math.sin(beta*(2*k-1))
    * Math.sin(2.0*Math.PI*(2*k-1)*freq*n/N)
    / Math.pow(2*k-1,2.0);
    }
    }
    return x;
  }

  /**
   * <pre>
   * 	-Berechnet aufgrund der Parameter Rechtecksignal
   * </pre>
   *
   * @param amp
   * @param freq
   * @param nHarm
   * @return
   */
  private double[] berechneRechteck(double amp, double freq, int nHarm, int N) {
	  double[] x = new double[N];
      for (double n = 0; n < N; n++) {
          for (double k = 1; k <= nHarm; k++) {

              x[(int) n] += (4.0 * amp / Math.PI)
                      * (Math.sin(2.0 * Math.PI * freq * ((2.0 * k) - 1.0) * (n / N)) / ((2.0 * k) - 1.0));
          }
      }
      return x;
  }

  /**
   * <pre>
   * 	-Berechnet aufgrund der Parameter Dreiecksignal
   * </pre>
   *
   * @param amp
   * @param freq
   * @param nHarm
   * @return
   */
  private double[] berechneDreieck(double amp, double freq, int nHarm, int N) {
      //trace.methodeCall();
      double[] x = new double[N];
      for (double n = 0; n < N; n++) {
          for (double k = 1; k <= nHarm; k++) {
              if (k % 2 == 0) {
                  x[(int) n] -= (4.0 * amp / Math.PI) * (Math.sin(2.0 * Math.PI * freq * ((2.0 * k) - 1.0) * (n / N))
                          / Math.pow(((2.0 * k) - 1.0), 2));
              } else {
                  x[(int) n] += (4.0 * amp / Math.PI) * (Math.sin(2.0 * Math.PI * freq * ((2.0 * k) - 1.0) * (n / N))
                          / Math.pow(((2.0 * k) - 1.0), 2));
              }
          }
      }
      return x;
  }

  /**
   * <pre>
   * 	-Berechnet aufgrund der Parameter Sägezahnsignal
   * </pre>
   *
   * @param amp
   * @param freq
   * @param nHarm
   * @return
   */
  private double[] berechneSaegezahn(double amp, double freq, int nHarm, int N) {
	  double[] x = new double[N];

	  double omega = (Math.PI * 2.0 * freq)/620;

	    for (int harms = 1; harms<= nHarm; harms++) {
	    for (int n = 0; n< N; n++) {
	    	x[n] += ((amp*2) * Math.sin(n*omega*harms))/harms;
	    }
	    }
  return x;
  }

@Override
public void stateChanged(ChangeEvent arg0) {
	// TODO Auto-generated method stub
	btBerechne.doClick();
}

}

public class FourierPanelFrame extends JFrame {


  public static void main(String args[]) {
    TraceV7.mainCall();
    FourierPanelFrame frame = new FourierPanelFrame();
    frame.addWindowListener(new WindowAdapter() {
      public void windowClosing(WindowEvent e) {
        System.exit(1);
      }
    });
    FourierPanel view = new FourierPanel();
    frame.add(view);
    frame.setSize(720, 720); //720x720
   // frame.setLayout(null);
    //frame.setIconImage(icon);
    frame.setTitle("|FHNW|EIT|OOP|Fourier-Panel|");
    frame.setResizable(true);
    frame.setVisible(true);


  }
}