import java.applet.*;
import java.awt.*;
import java.util.Vector;

public class SLDCalculator extends Applet {
    TextField chemicalField, densityField, lambdaField;
    Button calculate;
    Label incohLabel, absorbLabel, lengthLabel, neutronLabel;
    Label xrayCuLabel, xrayMoLabel;
    Vector elementVector;
    double density, wavelength;
     
    public void init() {
        Font font = new Font("TimesRoman",Font.PLAIN,12);
        setLayout(new GridLayout(0,2));
        setBackground(Color.white);

        Label compoundLabel = new Label("Compound");
        compoundLabel.setFont(font);
        chemicalField = new TextField(20);
        chemicalField.setFont(font);
        add(compoundLabel);
        add(chemicalField);

        Label densityLabel = new Label("Density (g/cm^3)");
        densityLabel.setFont(font);
        densityField = new TextField(20);
        densityField.setFont(font);
        add(densityLabel);
        add(densityField);

        Label lambdaLabel = new Label("Wavelength (A)");
        lambdaLabel.setFont(font);
        lambdaField = new TextField(20);
        lambdaField.setFont(font);
        add(lambdaLabel);
        add(lambdaField);

        Label spacer = new Label("  ");
        spacer.setFont(font);
        calculate = new Button("Calculate");
        calculate.setFont(font);
        add(spacer);
        add(calculate);

        Label neutronExplLabel = new Label("Neutron SLD");
        neutronExplLabel.setFont(font);
        add(neutronExplLabel);
        neutronLabel = new Label("0.00e-6 + 0.00e-6i (A^-2)");
        neutronLabel.setFont(font);
        add(neutronLabel);

        Label xrayExplCuLabel = new Label("Cu Ka SLD");
        xrayExplCuLabel.setFont(font);
        add(xrayExplCuLabel);
        xrayCuLabel = new Label("0.00e-6 + 0.00e-6i (A^-2)");
        xrayCuLabel.setFont(font);
        add(xrayCuLabel);

        Label xrayExplMoLabel = new Label("Mo Ka SLD");
        xrayExplMoLabel.setFont(font);
        add(xrayExplMoLabel);
        xrayMoLabel = new Label("0.00e-6 + 0.00e-6i (A^-2)");
        xrayMoLabel.setFont(font);
        add(xrayMoLabel);

        Label incohExplLabel = new Label("Neutron Inc. XS");
        incohExplLabel.setFont(font);
        add(incohExplLabel);
        incohLabel = new Label("0.00 (cm^-1)");
        incohLabel.setFont(font);
        add(incohLabel);

        Label absorbExplLabel = new Label("Neutron Abs. XS");
        absorbExplLabel.setFont(font);
        add(absorbExplLabel);
        absorbLabel = new Label("0.00 (cm^-1)");
        absorbLabel.setFont(font);
        add(absorbLabel);

        Label lengthExplLabel = new Label("Neutron 1/e length");
        lengthExplLabel.setFont(font);
        add(lengthExplLabel);
        lengthLabel = new Label("0.00 (cm)");
        lengthLabel.setFont(font);
        add(lengthLabel);

        validate();
    }

    public boolean action(Event e, Object a) {

        if (e.target instanceof Button) {

            //parse chemical field
            String inputString = chemicalField.getText();
            try {
                elementVector = NCNRUtils.parseCompound(inputString);
            } catch (BadCompoundException exc) {
                neutronLabel.setText(exc.getMessage());
                incohLabel.setText(exc.getMessage());
                absorbLabel.setText(exc.getMessage());
                lengthLabel.setText(exc.getMessage());
                return true;
            }

            //parse density field
            density=-1.;
            String errorText = "Bad Value for Density";
            try {
                density=Double.valueOf(densityField.getText()).doubleValue();
            } catch (NumberFormatException exc) {
                neutronLabel.setText(errorText);
                xrayCuLabel.setText(errorText);
                xrayMoLabel.setText(errorText);
                incohLabel.setText(errorText);
                absorbLabel.setText(errorText);
                lengthLabel.setText(errorText);
                return true;
            }
            if((density <= 0.0) || Double.isNaN(density)){
                neutronLabel.setText(errorText);
                xrayCuLabel.setText(errorText);
                xrayMoLabel.setText(errorText);
                incohLabel.setText(errorText);
                absorbLabel.setText(errorText);
                lengthLabel.setText(errorText);
                return true;
            }

            //parse wavelength field
            wavelength=1.8;
            try {
                wavelength=Double.valueOf(lambdaField.getText()).doubleValue();
            } catch (NumberFormatException exc) { 
                lambdaField.setText(String.valueOf(1.8));
            }
            if (wavelength <= 0.0) {
                wavelength = 1.8;
                lambdaField.setText(String.valueOf(1.8));
            }

            String signString = "+";
            String outputText = "";
            String realText ="";
            double[] output = NCNRUtils.calculateSLD(elementVector, 
                                                     density, 
                                                     wavelength);
            double tempValue;
            double count;
            long tempSLD;
            //Arrange neutron SLD label
            if(Double.isNaN(output[0])) {
                outputText = "That data not available.";
                neutronLabel.setText(outputText);
            } else {
                realText = String.valueOf(NCNRUtils.sigfigs(output[0],3));
                if(output[1] != 0.0) {
                    if(output[1] < 0.0) signString = "";
                    outputText = realText+" "+signString
                        +String.valueOf(NCNRUtils.sigfigs(output[1],3))+"i (A^-2)";
                } else { 
                    outputText = realText+" (A^-2)";
                }
                neutronLabel.setText(outputText);
            }
            //Arrange x-ray SLD label
            signString = "+";
            if(Double.isNaN(output[2])) {
                outputText = "That data not available.";
                xrayCuLabel.setText(outputText);
                xrayMoLabel.setText(outputText);
            } else {
                realText = String.valueOf(NCNRUtils.sigfigs(output[2],3));
                if(output[3] != 0.0) {
                    if(output[3] < 0.0) signString = "";
                    outputText = realText+" "+signString
                        +String.valueOf(NCNRUtils.sigfigs(output[3],3))+"i (A^-2)";
                } else { 
                    outputText = realText+" (A^-2)";
                }
                xrayCuLabel.setText(outputText);
                realText = String.valueOf(NCNRUtils.sigfigs(output[4],3));
                if(output[5] != 0.0) {
                    if(output[5] < 0.0) signString = "";
                    outputText = realText+" "+signString
                        +String.valueOf(NCNRUtils.sigfigs(output[5],3))+"i (A^-2)";
                } else { 
                    outputText = realText+" (A^-2)";
                }
                xrayMoLabel.setText(outputText);
            }
            if((Double.isNaN(output[6]))||(Double.isNaN(output[9]))) {
                outputText = "That data not available.";
                incohLabel.setText(outputText);
            } else {
                realText  = String.valueOf(NCNRUtils.sigfigs(output[6],3));
                //realText += "; "+String.valueOf(NCNRUtils.sigfigs(output[9],3));
                outputText = realText+" (cm^-1)";
                incohLabel.setText(outputText);
            }
            if(Double.isNaN(output[7])) {
                outputText = "That data not available.";
                absorbLabel.setText(outputText);
            } else {
                realText = String.valueOf(NCNRUtils.sigfigs(output[7],3));
                outputText = realText+" (cm^-1)";
                absorbLabel.setText(outputText);
            }
            if(Double.isNaN(output[8])) {
                outputText = "That data not available.";
                lengthLabel.setText(outputText);
            } else {
                realText = String.valueOf(NCNRUtils.sigfigs(output[8],3));
                outputText = realText+" (cm)";
                lengthLabel.setText(outputText);
            }
        }
        return true;
    }

}