package edu.princeton.toy;

import java.awt.*;
import java.awt.event.*;

import javax.swing.*;
import javax.swing.event.*;
import javax.swing.text.*;

import edu.princeton.swing.*;
import edu.princeton.toy.lang.*;

/**
 * TBaseConvertPanel is a JPanel which acts as a base converter.
 *
 * @author btsang
 * @version 7.1
 */
public class TBaseConverterPane extends JPanel
{
    /**
     * The font which this TBaseConverterPane starts out with.
     */
    public static final Font DEFAULT_FONT = new Font("Dialog", Font.PLAIN, 12);

    private Document binaryDocument, decimalDocument, hexDocument, pseudoCodeDocument;

    private boolean ignoreBinaryDocument, ignoreDecimalDocument, ignoreHexDocument;

    private Listener listener;

    /**
     * Creates a new TBaseConverterPane.
     */
    public TBaseConverterPane()
    {
        this(TWord.ZERO);
    }

    /**
     * Creates a new TBaseConverterPane.
     */
    public TBaseConverterPane(TWord initialValue)
    {
        super(new GridBagLayout(), true);

        if (initialValue == null)
            throw new NullPointerException();

        setFont(DEFAULT_FONT);

        add(
            new JLabel("Base Converter"),
            new GridBagConstraints(
                0, 0, 2, 1,
                1.0, 1.0,
                GridBagConstraints.NORTHWEST,
                GridBagConstraints.NONE,
                new Insets(2, 2, 2, 2),
                0, 0
                )
            );

        add(
            new JLabel("Binary"),
            new GridBagConstraints(
                0, 1, 1, 1,
                1.0, 1.0,
                GridBagConstraints.NORTHWEST,
                GridBagConstraints.NONE,
                new Insets(2, 2, 2, 2),
                0, 0
                )
            );

        add(
            new JLabel("Decimal"),
            new GridBagConstraints(
                0, 2, 1, 1,
                1.0, 1.0,
                GridBagConstraints.NORTHWEST,
                GridBagConstraints.NONE,
                new Insets(2, 2, 2, 2),
                0, 0
                )
            );

        add(
            new JLabel("Hexadecimal"),
            new GridBagConstraints(
                0, 3, 1, 1,
                1.0, 1.0,
                GridBagConstraints.NORTHWEST,
                GridBagConstraints.NONE,
                new Insets(2, 2, 2, 2),
                0, 0
                )
            );

        add(
            new JLabel("Pseudocode"),
            new GridBagConstraints(
                0, 4, 1, 1,
                1.0, 1.0,
                GridBagConstraints.NORTHWEST,
                GridBagConstraints.NONE,
                new Insets(2, 2, 2, 2),
                0, 0
                )
            );

        listener = new Listener();

        PTextField textField;

        textField = new PTextField(17);
        textField.setFont(null);
        binaryDocument = textField.getDocument();
        binaryDocument.addDocumentListener(listener);
        add(
            textField,
            new GridBagConstraints(
                1, 1, 1, 1,
                5.0, 1.0,
                GridBagConstraints.NORTHWEST,
                GridBagConstraints.HORIZONTAL,
                new Insets(2, 2, 2, 2),
                0, 0
                )
            );

        textField = new PTextField(17);
        textField.setFont(null);
        decimalDocument = textField.getDocument();
        decimalDocument.addDocumentListener(listener);
        add(
            textField,
            new GridBagConstraints(
                1, 2, 1, 1,
                5.0, 1.0,
                GridBagConstraints.NORTHWEST,
                GridBagConstraints.HORIZONTAL,
                new Insets(2, 2, 2, 2),
                0, 0
                )
            );

        textField = new PTextField(17);
        textField.setFont(null);
        hexDocument = textField.getDocument();
        hexDocument.addDocumentListener(listener);
        add(
            textField,
            new GridBagConstraints(
                1, 3, 1, 1,
                5.0, 1.0,
                GridBagConstraints.NORTHWEST,
                GridBagConstraints.HORIZONTAL,
                new Insets(2, 2, 2, 2),
                0, 0
                )
            );

        textField = new PTextField(17);
        textField.setFont(null);
        textField.setEditable(false);
        pseudoCodeDocument = textField.getDocument();
        add(
            textField,
            new GridBagConstraints(
                1, 4, 1, 1,
                5.0, 1.0,
                GridBagConstraints.NORTHWEST,
                GridBagConstraints.HORIZONTAL,
                new Insets(2, 2, 2, 2),
                0, 0
                )
            );

        setValue(initialValue, null);
    }

    /**
     * Sets the value currently displayed by the TBaseConverterPane.
     *
     * @param value The new value the TBaseConverterPane should display.  If the value is
     * uninitialized, nothing will be displayed.  If the value is null, a NullPointerException
     * will be thrown.
     */
    public void setValue(TWord value)
    {
        setValue(value, null);
    }

    /**
     * Sets the value currently displayed by the TBaseConverterPane.
     *
     * @param value The new value the TBaseConverterPane should display.  If the value is
     * uninitialized, nothing will be displayed.  If the value is null, a NullPointerException
     * will be thrown.
     * @param source The source of the change.  This source will not be modified.  A null value
     * will indicate that all PTextFields should be updated.
     */
    protected void setValue(TWord value, Document source)
    {
        if (value == null)
            throw new NullPointerException();

        if (source != binaryDocument)
        {
            ignoreBinaryDocument = true;

            try
            {
                binaryDocument.remove(0, binaryDocument.getLength());

                if (value.isInitialized())
                    binaryDocument.insertString(0, value.toBinaryString(false), null);
            }
            catch (Exception e)
            {
                e.printStackTrace();
            }

            ignoreBinaryDocument = false;
        }

        if (source != decimalDocument)
        {
            ignoreDecimalDocument = true;

            try
            {
                decimalDocument.remove(0, decimalDocument.getLength());

                if (value.isInitialized())
                    decimalDocument.insertString(0, String.valueOf(value.getValue()), null);
            }
            catch (Exception e)
            {
                e.printStackTrace();
            }

            ignoreDecimalDocument = false;
        }

        if (source != hexDocument)
        {
            ignoreHexDocument = true;

            try
            {
                hexDocument.remove(0, hexDocument.getLength());

                if (value.isInitialized())
                    hexDocument.insertString(0, value.toHexString(false), null);
            }
            catch (Exception e)
            {
                e.printStackTrace();
            }

            ignoreHexDocument = false;
        }

        try
        {
            pseudoCodeDocument.remove(0, pseudoCodeDocument.getLength());

            if (value.isInitialized())
                pseudoCodeDocument.insertString(0, value.toPseudoCodeString(false), null);
        }
        catch (Exception e)
        {
            e.printStackTrace();
        }
    }

    /**
     * Parses the text of a document and passes the data to setValue().
     *
     * @param source The Document which changed.
     */
    private void documentChanged(Document source)
    {
        if (source == binaryDocument)
        {
            if (!ignoreBinaryDocument)
            {
                try
                {
                    setValue(
                        TWord.parseWord(
                            binaryDocument.getText(0, binaryDocument.getLength()),
                            2
                            ),
                        binaryDocument
                        );
                }
                catch (NumberFormatException e)
                {
                    setValue(TWord.UNINITIALIZED_VALUE, binaryDocument);
                }
                catch (Exception e)
                {
                    e.printStackTrace();
                    setValue(TWord.UNINITIALIZED_VALUE, binaryDocument);
                }
            }
        }
        else if (source == decimalDocument)
        {
            if (!ignoreDecimalDocument)
            {
                try
                {
                    setValue(
                        TWord.parseWord(
                            decimalDocument.getText(0, decimalDocument.getLength()),
                            10
                            ),
                        decimalDocument
                        );
                }
                catch (NumberFormatException e)
                {
                    setValue(TWord.UNINITIALIZED_VALUE, decimalDocument);
                }
                catch (Exception e)
                {
                    e.printStackTrace();
                    setValue(TWord.UNINITIALIZED_VALUE, decimalDocument);
                }
            }
        }
        else if (source == hexDocument)
        {
            if (!ignoreHexDocument)
            {
                try
                {
                    setValue(
                        TWord.parseWord(
                            hexDocument.getText(0, hexDocument.getLength()),
                            16
                            ),
                        hexDocument
                        );
                }
                catch (NumberFormatException e)
                {
                    setValue(TWord.UNINITIALIZED_VALUE, hexDocument);
                }
                catch (Exception e)
                {
                    e.printStackTrace();
                    setValue(TWord.UNINITIALIZED_VALUE, hexDocument);
                }
            }
        }
        else {
            throw new IllegalArgumentException();
        }
    }

    /**
     * The Listener of a TBaseConverterPane pays attention to the changes in the PTextFields, and
     * fires off changes to the other PTextFields.
     *
     * @author btsang
     * @version 7.1
     */
    protected class Listener implements DocumentListener
    {
        /**
         * Implement DocumentListener to pass DocumentEvents to the documentChanged() method.
         */
        public void changedUpdate(DocumentEvent e) 
        {
            documentChanged(e.getDocument());
        }

        /**
         * Implement DocumentListener to pass DocumentEvents to the documentChanged() method.
         */
        public void insertUpdate(DocumentEvent e)
        {
            documentChanged(e.getDocument());
        }

        /**
         * Implement DocumentListener to pass DocumentEvents to the documentChanged() method.
         */
        public void removeUpdate(DocumentEvent e)
        {
            documentChanged(e.getDocument());
        }
    }
}