/*
 * Copyright 2008 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */
package com.google.gwt.gen2.table.client;

import java.util.*;

import com.google.gwt.core.client.*;
import com.google.gwt.user.client.ui.*;

/**
 * An {@link InlineCellEditor} that allows the user to select a {@link String}
 * from a list of {@link RadioButton RadioButtons}.
 *
 * @param <ColType> the data type of the column
 */
public class RadioCellEditor<ColType> extends InlineCellEditor<ColType>
{
    /**
     * A mapping of {@link RadioButton RadioButtons} to the value for the buttons.
     */
    private Map<RadioButton, ColType> radioMap = new HashMap<RadioButton, ColType>();

    /**
     * The vertical panel used to layout the contents.
     */
    private VerticalPanel vpanel = new VerticalPanel();

    /**
     * Construct a new {@link RadioCellEditor}.
     */
    public RadioCellEditor()
    {
        this( GWT.<InlineCellEditorImages>create( InlineCellEditorImages.class ) );
    }

    /**
     * Construct a new {@link RadioCellEditor} with the specified images.
     *
     * @param images the images to use for the accept/cancel buttons
     */
    public RadioCellEditor( InlineCellEditorImages images )
    {
        this( new VerticalPanel(), images );
    }

    /**
     * Constructor.
     *
     * @param images the images to use for the accept/cancel buttons
     */
    private RadioCellEditor( VerticalPanel vPanel, InlineCellEditorImages images )
    {
        super( vPanel, images );
        this.vpanel = vPanel;
    }

    /**
     * Add a {@link RadioButton} to the editor.
     *
     * @param radio the radio button to add
     * @param value the value associated with the {@link RadioButton}
     */
    public void addRadioButton( RadioButton radio, ColType value )
    {
        vpanel.add( radio );
        radioMap.put( radio, value );
    }

    @Override
    public void editCell( CellEditInfo cellEditInfo, ColType cellValue, Callback<ColType> callback )
    {
        super.editCell( cellEditInfo, cellValue, callback );
        Iterator<Widget> it = vpanel.iterator();
        while ( it.hasNext() )
        {
            RadioButton radio = (RadioButton) it.next();
            if ( radio.getValue() )
            {
                radio.setFocus( true );
                return;
            }
        }
    }

    /**
     * Insert a {@link RadioButton} at the specified index.
     *
     * @param radio       the radio button to add
     * @param value       the value associated with the {@link RadioButton}
     * @param beforeIndex the index before which it will be inserted
     *
     * @throws IndexOutOfBoundsException if <code>beforeIndex</code> is out of
     *                                   range
     */
    public void insertRadioButton( RadioButton radio, ColType value, int beforeIndex )
            throws IndexOutOfBoundsException
    {
        vpanel.insert( radio, beforeIndex );
        radioMap.put( radio, value );
    }

    /**
     * Remove a {@link RadioButton} from the editor.
     *
     * @param radio the radio button to remove
     */
    public void removeRadioButton( RadioButton radio )
    {
        vpanel.remove( radio );
        radioMap.remove( radio );
    }

    @Override
    protected ColType getValue()
    {
        Iterator<Widget> it = vpanel.iterator();
        while ( it.hasNext() )
        {
            RadioButton radio = (RadioButton) it.next();
            if ( radio.getValue() )
            {
                return radioMap.get( radio );
            }
        }
        return null;
    }

    @Override
    protected void setValue( ColType cellValue )
    {
        for ( Map.Entry<RadioButton, ColType> entry : radioMap.entrySet() )
        {
            if ( entry.getValue().equals( cellValue ) )
            {
                entry.getKey().setValue( true );
            }
            else
            {
                entry.getKey().setValue( false );
            }
        }
    }
}