package edu.princeton.toy.choosers;

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

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

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

/**
 * TAutoCompleteChooserPane manages the options related to the autocomplete feature of toy.
 *
 * @author btsang
 * @version 7.1
 */
public class TAutoCompleteChooserPane extends JPanel
{
    private static final String CLASS_STRING = TAutoCompleteChooserPane.class.toString();

    /**
     * The command doesn't do anything at present.
     */
    public static final String UPDATE_COMMAND = CLASS_STRING + "#updateCommand";

    private ButtonModel buttonModels[];
    private ButtonGroup group;

    /**
     * Creates a new TAutoCompleteChooserPane which has only the given autoCompleters available.
     */
    public TAutoCompleteChooserPane(String autoCompleterNames[])
    {
        super(new GridBagLayout());

        int length = autoCompleterNames.length;
        buttonModels = new ButtonModel[length];
        group = new ButtonGroup();

        add(
            new JLabel("Available AutoCompleters"),
            new GridBagConstraints(
                0, 0, 1, 1,
                1.0, 1.0,
                GridBagConstraints.SOUTHWEST,
                GridBagConstraints.NONE,
                new Insets(2, 2, 2, 2),
                0, 0
                )
            );

        for (int ctr = 0; ctr < length; ctr++)
        {
            if (autoCompleterNames[ctr] == null)
                throw new NullPointerException();

            JRadioButton radioButton = new JRadioButton(autoCompleterNames[ctr], null, ctr == 0);

            buttonModels[ctr] = radioButton.getModel();
            group.add(radioButton);

            add(
                radioButton,
                new GridBagConstraints(
                    0, ctr + 1, 1, 1,
                    0.0, (ctr == length - 1)?1.0:0.0,
                    GridBagConstraints.NORTHWEST,
                    GridBagConstraints.NONE,
                    new Insets(2, 2, 2, 2),
                    0, 0
                    )
                );
        }
    }

    /**
     * Returns the index of the autoCompleter which should be used when editing a TOY program.
     *
     * @return The index of the autoCompleter which should be used when editing a TOY program.
     */
    public int getAutoCompleterId()
    {
        for (int ctr = 0; ctr < buttonModels.length; ctr++)
            if (buttonModels[ctr].isSelected())
                return ctr;

        return 0;
    }

    /**
     * Sets the index of the autoCompleter which should be used when editing a TOY program.
     *
     * @param autoCompleterId The index of the autoCompleter which should be used when editing a
     * TOY program.  If this is invalid, an IllegalArgumentException will be thrown.
     */
    public void setAutoCompleterId(int autoCompleterId)
    {
        buttonModels[autoCompleterId].setSelected(true);
    }

    /**
     * Performs a command based on the argument.
     *
     * @param command A string representing the command.  Note that pointer equality (not string
     * equality) is tested here, so it is important to use the string constants defined in this
     * class.  An IllegalArgumentException will be thrown if the argument is invalid.
     * @return True iff the command was executed sucessfully.
     */
    public synchronized boolean doCommand(String command, Object extraInfo)
    {
        ////////////////////////////////////////////////////////////////////////////////////////////
        if (command == UPDATE_COMMAND)
        {

            return true;
        }

        throw new IllegalArgumentException();
    }
}