package math;

import java.applet.Applet;
import java.awt.Button;
import java.awt.Checkbox;
import java.awt.CheckboxGroup;
import java.awt.Color;
import java.awt.GridBagConstraints;
import java.awt.Label;
import java.awt.Panel;
import java.awt.TextArea;
import java.awt.TextField;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.FocusAdapter;
import java.awt.event.FocusEvent;
import java.awt.event.InputEvent;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import java.awt.event.MouseAdapter;
import java.awt.event.MouseEvent;

/**
   This applet provides an interface to a CompGraph Object which will
   graph a complex function using color to plot a 4th dimension.
   Last updated February 26, 2001
   (copyright 1997-2001)
<pre>
The argument principle
f(z) = z
f(z) = z^2
f(z) = z^2+1
f(z) = 1/z
f(z) = (z^2 + 1)/z
Branch cuts and Riemann surfaces
f(z) = sqrt(z)
f(z) = -sqrt(z)
Periodicity of the the complex exponential function
f(z) = exp(pi*z), or alternatively
f(z) = exp(z) (change domain to -6.28 <= Im(z) <= 6.28)
Regular and hyperbolic trig functions
f(z) = cos(pi*z)
f(z) = cosh(pi*z)
Alternatively they can look at cos(z) and cosh(z) with the domains set to 
-6.28 <= Re(z) <= 6.28, -2 <= Im(z) <= 2 for cos and 
-2 <= Re(z) <= 2, -6.28 <= Im(z) <= 6.28 for cosh</pre>
   @version 1.0
   @author Andrew G. Bennett
   @see <a href="http://www.math.ksu.edu/~bennett/jomacg/">http://www.math.ksu.edu/~bennett/jomacg/</a>
 */
public class CGApplet extends Applet implements ItemListener {

    /**
	 * UID
	 */
	private static final long serialVersionUID = 8483989289337953145L;
	/** 
        Initializations
    */
	public void init() {
		super.init();
		fzactive=true;
		helpactive=true;
		dpactive=true;

        // No Layout Manager
		setLayout(null);
		addNotify();
		resize(500,400);

        // Help Screen Panel
        helpPanel=new Panel(null);
        helpPanel.setBounds(70,25,360,310);
        helpPanel.setBackground(Color.lightGray);
        helpPanel.setVisible(false);
        add(helpPanel);
        helptextString=new String(
            "Graphing a complex function is difficult because you\n" 
            +"need 2 (real) dimensions for the domain and 2 (real)\n"
            +"dimensions for the range - a total of 4 dimensions.\n"
            +"In this applet, the domain of a complex function is\n"
            +"graphed on the base plane. The range is graphed using\n"
            +"polar coordinates. The modulus (magnitude) of the\n"
            +"complex function is graphed on the vertical axis. The\n"
            +"argument (angle) is graphed by using different colors:\n"
            +"light blue for positive real, dark blue (shading to\n"
            +"purple) for positive imaginary, red for negative real,\n"
            +"and yellow-green for negative imaginary. This allows\n"
            +"four dimensions to be represented in three spatial\n"
            +"dimensions, which are then projected onto a two\n"
            +"dimensional screen using a simple orthogonal\n"
            +"projection.\n\n"
            +"Enter complex functions into the f(z) = text box using\n"
            +"standard calculator notation. You must use * for\n"
            +"multiplication, i.e. 2*z not 2z. Functions must have\n"
            +"parentheses, i.e. sin(z) not sin z. The parser\n"
            +"understands the following operations, functions, and\n"
            +"constants: +, -, *, /, ^, sqrt(), sin(), cos(), tan(),\n"
            +"exp(),  ln(), log() (synonymous with ln), sinh(), cosh(),\n"
            +"abs(), mod() (synonymous with abs), arg(), conj(),\n"
            +"e, pi, i.\n\n"
            +"To adjust the domain of the graph, right-click (or\n"
            +"shift-click if you have a one-button mouse) on the\n"
            +"graph. The domain editor only accepts numerical input,\n"
            +"i.e. 3.14 not pi.");
        helpTextArea=new TextArea(helptextString,20,55,TextArea.SCROLLBARS_VERTICAL_ONLY);
        helpTextArea.setBounds(10,10,340,270);
        helpTextArea.setEditable(false);
        helpPanel.add(helpTextArea);
        helpcloseButton=new Button("Close");
        helpcloseButton.addActionListener(new ActionListener() {
            public void actionPerformed(ActionEvent evt) {
                closeHelp();
            }
        });
        helpcloseButton.setBounds(145,285,70,20);
        helpPanel.add(helpcloseButton);
        
		// Edit Domain Panel
		dp=new Panel(null);
		dp.setBounds(125,85,250,190);
		dp.setBackground(Color.lightGray);
		dp.setVisible(false);
		add(dp);
		// Re(z) Values
		rLabel=new Label("Re(z):");
		rLabel.setBounds(5,10,40,20);
		dp.add(rLabel);
		rminLabel=new Label("min ",Label.RIGHT);
		rminLabel.setBounds(45,10,30,20);
		dp.add(rminLabel);
		rminTextField=new TextField("-2.0");
		rminTextField.setBounds(75,10,70,20);
		dp.add(rminTextField);
		rmaxLabel=new Label("max ",Label.RIGHT);
		rmaxLabel.setBounds(145,10,30,20);
		dp.add(rmaxLabel);
		rmaxTextField=new TextField("2.0");
		rmaxTextField.setBounds(175,10,70,20);
		dp.add(rmaxTextField);
		// Im(z) Values
		iLabel=new Label("Im(z):");
		iLabel.setBounds(5,50,40,20);
		dp.add(iLabel);
		iminLabel=new Label("min ",Label.RIGHT);
		iminLabel.setBounds(45,50,30,20);
		dp.add(iminLabel);
		iminTextField=new TextField("-2.0");
		iminTextField.setBounds(75,50,70,20);
		dp.add(iminTextField);
		imaxLabel=new Label("max ",Label.RIGHT);
		imaxLabel.setBounds(145,50,30,20);
		dp.add(imaxLabel);
		imaxTextField=new TextField("2.0");
		imaxTextField.setBounds(175,50,70,20);
		dp.add(imaxTextField);
		// |f(z)| Values
		fLabel=new Label("|f(z)|:");
		fLabel.setBounds(5,90,40,20);
		dp.add(fLabel);
		fCGroup=new CheckboxGroup();
		fautoCheckbox=new Checkbox("auto",true,fCGroup);
		fautoCheckbox.setBounds(65,90,80,20);
		fautoCheckbox.addItemListener(this);
		dp.add(fautoCheckbox);
		fmanCheckbox=new Checkbox("manual",false,fCGroup);
		fmanCheckbox.setBounds(65,120,80,20);
		fmanCheckbox.addItemListener(this);
		dp.add(fmanCheckbox);
		fminLabel=new Label("min ",Label.RIGHT);
		fminLabel.setForeground(Color.gray);
		fminLabel.setBounds(145,90,30,20);
		dp.add(fminLabel);
		fminTextField=new TextField("0.0");
		fminTextField.setForeground(Color.gray);
		fminTextField.setBounds(175,90,70,20);
		fminTextField.setEditable(false);
		// Prevent it gaining focus if fauto checked
		fminTextField.addFocusListener(new FocusAdapter() {
		    public void focusGained(FocusEvent evt) {
		        if (fautoCheckbox.getState()) {
		            fminLabel.requestFocus();
		        }
		    }
		});
		dp.add(fminTextField);
		fmaxLabel=new Label("max ",Label.RIGHT);
		fmaxLabel.setForeground(Color.gray);
		fmaxLabel.setBounds(145,120,30,20);
		dp.add(fmaxLabel);
		fmaxTextField=new TextField("3.0");
		fmaxTextField.setForeground(Color.gray);
		fmaxTextField.setBounds(175,120,70,20);
		fmaxTextField.setEditable(false);
		// Prevent it gaining focus if fauto checked
		fmaxTextField.addFocusListener(new FocusAdapter() {
		    public void focusGained(FocusEvent evt) {
		        if (fautoCheckbox.getState()) {
		            fmaxLabel.requestFocus();
		        }
		    }
		}); 
		dp.add(fmaxTextField);		
		// Domain Buttons
		okButton=new Button("OK");
		okButton.setBounds(35,150,60,20);
		okButton.addActionListener(new ActionListener() {
		    public void actionPerformed(ActionEvent evt) {
		        okdp();
		    }
		});
		dp.add(okButton);
		resetButton=new Button("Defaults");
		resetButton.setBounds(95,150,60,20);
		resetButton.addActionListener(new ActionListener() {
		    public void actionPerformed(ActionEvent evt) {
		        resetdp();
		    }
		});
		dp.add(resetButton);
		cancelButton=new Button("Cancel");
		cancelButton.setBounds(155,150,60,20);
		cancelButton.addActionListener(new ActionListener() {
		    public void actionPerformed(ActionEvent evt) {
		        canceldp();
		    }
		});
		dp.add(cancelButton);
		// Message Label (for errors)
		messLabel=new Label("",Label.CENTER);
		messLabel.setForeground(Color.red);
		messLabel.setBounds(5,170,240,20);
		dp.add(messLabel);
		
		// CompGraph to plot graph
		c3d=new CompGraph();
		c3d.setBackground(Color.black);
		c3d.setBounds(45,5,410,350);
		c3d.addMouseListener(new MouseAdapter() {
		    public void mouseClicked(MouseEvent evt) {
		        if ((evt.getModifiers()&InputEvent.BUTTON3_MASK)>0 
		                                       || evt.isShiftDown()) {
		            showdp();
		            }
		    }
		});
		add(c3d);
		// Label "f(z) ="
		fzLabel=new Label("f(z)  =",Label.CENTER);
		fzLabel.setBounds(10,360,50,20);
		add(fzLabel);
		// TextField to input f(z)
		fzTextField=new TextField("z");
		fzTextField.setBounds(60,360,265,20);
		fzTextField.addActionListener(new ActionListener() {
		    public void actionPerformed(ActionEvent e) {
		        if (!fzactive) return;
		        emLabel.setText("");
		        try {
    		        c3d.setfct(fzTextField.getText());
    		        c3d.repaint();
		        } catch (Exception except) {
    		        emLabel.setText("Unable to evaluate f(z)");
    		    }
		    }
		});
		add(fzTextField);
		// Change view to "top" button
		tvButton=new Button("Top View");
		tvButton.setBounds(340,360,70,20);
		tvButton.addActionListener(new ActionListener() {
		    public void actionPerformed(ActionEvent e) {
		        if (!fzactive) return;
		        c3d.setView("top");
		        emLabel.setText("");
		        try {
    		        c3d.setfct(fzTextField.getText());
    		        c3d.repaint();
		        } catch (Exception except) {
    		        emLabel.setText("Unable to evaluate f(z)");
    		    }
		    }
		});
		add(tvButton);
		// Change view to "side" button
		svButton=new Button("Side View");
		svButton.setBounds(410,360,70,20);
		svButton.addActionListener(new ActionListener() {
		    public void actionPerformed(ActionEvent e) {
		        if (!fzactive) return;
		        c3d.setView("side");
		        emLabel.setText("");
		        try {
    		        c3d.setfct(fzTextField.getText());
    		        c3d.repaint();
		        } catch (Exception except) {
    		        emLabel.setText("Unable to evaluate f(z)");
    		    }
		    }
		});
		add(svButton);
		helpButton=new Button("Help");
		helpButton.setBounds(410,380,70,20);
		helpButton.addActionListener(new ActionListener() {
		    public void actionPerformed(ActionEvent evt) {
		        if (!helpactive) return;
		        helpPanel.setVisible(true);
		        fzTextField.setEditable(false);
		        fzactive=false;
		        dpactive=false;
		    }
		});
		add(helpButton);
		
		// Error Message Label
		emLabel=new Label("",Label.LEFT);
		emLabel.setForeground(Color.red);
		emLabel.setBounds(60,380,265,20);
		add(emLabel);
	}
	
	/**
	    Activate and Gray |f(z)| min & max
	    @param evt Change in auto/manual |f(z)| limit checkboxes
	*/
	public void itemStateChanged(ItemEvent evt) {
	    if (fautoCheckbox.getState()) { // Gray |f(z)| min & max
	        fminLabel.setForeground(Color.gray);
	        fminTextField.setForeground(Color.gray);
	        fminTextField.setEditable(false);
	        fmaxLabel.setForeground(Color.gray);
	        fmaxTextField.setForeground(Color.gray);
	        fmaxTextField.setEditable(false);
	    } else {    // Activate |f(z)| min & max
	        fminLabel.setForeground(Color.black);
	        fminTextField.setForeground(Color.black);
	        fminTextField.setEditable(true);
	        fmaxLabel.setForeground(Color.black);
	        fmaxTextField.setForeground(Color.black);
	        fmaxTextField.setEditable(true);
	    }
	}
	
	// Show Domain Panel
	private void showdp() {
	    if (!dpactive) return;
	    rminTextField.setText(String.valueOf(c3d.getxmin()));
	    rmaxTextField.setText(String.valueOf(c3d.getxmax()));
	    iminTextField.setText(String.valueOf(c3d.getymin()));
	    imaxTextField.setText(String.valueOf(c3d.getymax()));
	    fminTextField.setText(String.valueOf(c3d.getzmin()));
	    fmaxTextField.setText(String.valueOf(c3d.getzmax()));
	    if (c3d.getzauto()) {
	        fautoCheckbox.setState(true);
	        fminLabel.setForeground(Color.gray);
	        fminTextField.setForeground(Color.gray);
	        fminTextField.setEditable(false);
	        fmaxLabel.setForeground(Color.gray);
	        fmaxTextField.setForeground(Color.gray);
	        fmaxTextField.setEditable(false);
	    } else { 
	        fmanCheckbox.setState(true);
	        fminLabel.setForeground(Color.black);
	        fminTextField.setForeground(Color.black);
	        fminTextField.setEditable(true);
	        fmaxLabel.setForeground(Color.black);
	        fmaxTextField.setForeground(Color.black);
	        fmaxTextField.setEditable(true);
	    }
	    messLabel.setText("");
	    dp.setVisible(true);
	    fzactive=false;
	    helpactive=false;
	    fzTextField.setEditable(false);
	}
	
	// Domain Panel Okayed
	private void okdp() {
	    double rmin,rmax,imin,imax,fmin,fmax;
	    // Validate Input
	    try {
	        rmin=Double.valueOf(rminTextField.getText()).doubleValue();
	    } catch (NumberFormatException except) {
	        messLabel.setText("Can't Parse Re(z) min");
	        rminTextField.requestFocus();
	        return;
	    }
	    try {
	        rmax=Double.valueOf(rmaxTextField.getText()).doubleValue();
	    } catch (NumberFormatException except) {
	        messLabel.setText("Can't Parse Re(z) max");
	        rmaxTextField.requestFocus();
	        return;
	    }
	    try {
	        imin=Double.valueOf(iminTextField.getText()).doubleValue();
	    } catch (NumberFormatException except) {
	        messLabel.setText("Can't Parse Im(z) min");
	        iminTextField.requestFocus();
	        return;
	    }
	    try {
	        imax=Double.valueOf(imaxTextField.getText()).doubleValue();
	    } catch (NumberFormatException except) {
	        messLabel.setText("Can't Parse Im(z) max");
	        imaxTextField.requestFocus();
	        return;
	    }
	    fmin=0;fmax=3;
	    if (fmanCheckbox.getState()) {
	        try {
	            fmin=Double.valueOf(fminTextField.getText()).doubleValue();
	        } catch (NumberFormatException except) {
	            messLabel.setText("Can't Parse |f(z)| min");
	            fminTextField.requestFocus();
	        return;
	        }
	        try {
	            fmax=Double.valueOf(fmaxTextField.getText()).doubleValue();
	        } catch (NumberFormatException except) {
	            messLabel.setText("Can't Parse |f(z)| max");
	            fmaxTextField.requestFocus();
	            return;
	        }
        }
        if (rmin>=rmax) {
            messLabel.setText("Re(z) min must be less than max");
            rminTextField.requestFocus();
            return;
        }
        if (imin>=imax) {
            messLabel.setText("Im(z) min must be less than max");
            iminTextField.requestFocus();
            return;
        }
        if (fmanCheckbox.getState() && (fmin>=fmax)) {
            messLabel.setText("|f(z)| min must be less than max");
            fminTextField.requestFocus();
            return;
        }
        // Valid input so update domain and graph
        c3d.setLimits(rmin,rmax,imin,imax);
        if (fautoCheckbox.getState()) {
            c3d.setzauto(true);
        } else {
            c3d.setzauto(false);
            c3d.setzLimits(fmin,fmax);
        }
        c3d.setfct(fzTextField.getText());
        dp.setVisible(false);
        c3d.repaint();
        fzTextField.setEditable(true);
        fzactive=true;
        helpactive=true;
	}
	
	// Domain Panel reset
	private void resetdp() {
	    rminTextField.setText("-2.0");
	    rmaxTextField.setText("2.0");
	    iminTextField.setText("-2.0");
	    imaxTextField.setText("2.0");
	    fautoCheckbox.setState(true);
        fminLabel.setForeground(Color.gray);
        fminTextField.setForeground(Color.gray);
	    fmaxLabel.setForeground(Color.gray);
	    fmaxTextField.setForeground(Color.gray);
	    fzactive=true;
	    helpactive=true;
	    fzTextField.setEditable(true);
	}   
	
	// Domain Panel Cancelled
	private void canceldp() {
	    dp.setVisible(false);
	    fzactive=true;
	    helpactive=true;
	    fzTextField.setEditable(true);
	}
	
	// Close Help Panel
	private void closeHelp() {
	    helpPanel.setVisible(false);
	    fzactive=true;
	    dpactive=true;
	    fzTextField.setEditable(true);
	    c3d.repaint();
	}

	//DECLARE CONTROLS
	CompGraph c3d;
	Panel dp,helpPanel;
	GridBagConstraints constraints;
	Label fzLabel,emLabel,rLabel,rminLabel,rmaxLabel,
	      iLabel,iminLabel,imaxLabel,
	      fLabel,fminLabel,fmaxLabel,messLabel;
	TextField fzTextField,rminTextField,rmaxTextField,
	          iminTextField,imaxTextField,fminTextField,fmaxTextField;
	TextArea helpTextArea;
	String helptextString;
	Checkbox fautoCheckbox,fmanCheckbox;
	CheckboxGroup fCGroup;
	Button tvButton,svButton,helpcloseButton,helpButton,
	       okButton,resetButton,cancelButton;
	boolean fzactive,dpactive,helpactive;
}