/**
 * Copyright (C) 2015 Valkyrie RCP
 *
 * 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 org.valkyriercp.command.support;

import org.springframework.util.Assert;
import org.valkyriercp.command.config.CommandFaceDescriptor;

import javax.swing.*;
import java.awt.event.ActionEvent;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;

/**
 * An adapter between a Valkyrie RCP {@link ActionCommand} and the Swing
 * {@link javax.swing.Action} interface.
 *
 * <p>
 * This adheres to the standard GoF {@code Adapter} pattern whereby this class acts as
 * a wrapper around an underlying {@link ActionCommand} to give it the appearance of
 * being an {@link javax.swing.Action}.
 * </p>
 *
 * <p>
 * The {@link java.beans.PropertyChangeListener} interface is also implemented so that
 * instances can be notified of property change events being fired by their underlying command.
 * </p>
 */
public class SwingActionAdapter extends AbstractAction implements PropertyChangeListener {

    private ActionCommand command;

    /**
     * Creates a new {@code SwingActionAdapter} with the given underlying action command. The
     * newly created instance will add itself as a property change listener of the command.
     *
     * @param command The underlying action command.
     *
     * @throws IllegalArgumentException if {@code command} is null.
     */
    public SwingActionAdapter(ActionCommand command) {
        super();

        Assert.notNull(command, "command");
        this.command = command;
        command.addPropertyChangeListener(this);
        command.addEnabledListener(this);
        update();
    }

    /**
     * Delegates the handling of the given event to the underlying command.
     * @param event The action event to be handled.
     */
    public void actionPerformed(ActionEvent event) {
        command.actionPerformedHandler.actionPerformed(event);
    }

    /**
     * {@inheritDoc}
     */
    public void propertyChange(PropertyChangeEvent event) {
        update();
    }

    /**
     * Updates this instance according to the properties provided by the
     * underlying command.
     */
    protected void update() {
        putValue(Action.ACTION_COMMAND_KEY, command.getActionCommand());
        CommandFaceDescriptor face = command.getFaceDescriptor();
        if (face != null) {
            face.configure(this);
        }
        setEnabled(command.isEnabled());
    }

}