/*
 *  RapidMiner
 *
 *  Copyright (C) 2001-2011 by Rapid-I and the contributors
 *
 *  Complete list of developers available at our web site:
 *
 *       http://rapid-i.com
 *
 *  This program is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU Affero General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU Affero General Public License for more details.
 *
 *  You should have received a copy of the GNU Affero General Public License
 *  along with this program.  If not, see http://www.gnu.org/licenses/.
 */
package com.rapidminer.gui.tools;

import java.util.LinkedList;
import java.util.List;

import javax.swing.JTextField;
import javax.swing.SwingUtilities;
import javax.swing.event.DocumentEvent;
import javax.swing.event.DocumentListener;

/**
 * This extends the usual text field with a model, that will reflect the changes
 * to the content of the text field and offers a listener concept to be informed of the changes.
 * 
 * @author Sebastian Land
 */
public class ExtendedJTextField extends JTextField {
    private static final long serialVersionUID = -3490766980163546570L;

    public static interface TextChangeListener {
        /**
         * This method will be called, whenever the content of the textfield changes,
         * no matter if the changed happened by user input or programmatically.
         */
        public void informTextChanged(String newValue);
    }

    /**
     * This is the model of an {@link ExtendedJTextField}. It offers to set and
     * get the value and has a listener concept to be informed of changes to the
     * text content.
     *
     * @author Sebastian Land
     */
    public static class ExtendedJTextFieldModel {
        private String value;
        private List<TextChangeListener> listeners = new LinkedList<ExtendedJTextField.TextChangeListener>();

        public ExtendedJTextFieldModel() {}

        public ExtendedJTextFieldModel(String value) {
            this.value = value;
        }

        /**
         * This method must be called, when the model is added to the {@link ExtendedJTextField}.
         */
        /*pp*/ void registerOnComponent(final ExtendedJTextField component) {
            component.setText(value);
            // use a document listener instead of a KeyListener to react also on
            // programmatical changes
            component.getDocument().addDocumentListener(new DocumentListener() {
				@Override
				public void removeUpdate(DocumentEvent e) {
					changed(e);
				}
				
				@Override
				public void insertUpdate(DocumentEvent e) {
					changed(e);
				}
				
				@Override
				public void changedUpdate(DocumentEvent e) {
					changed(e);
				}
				
				private void changed(DocumentEvent e) {
                    SwingUtilities.invokeLater(new Runnable() {
                        @Override
                        public void run() {
                            setValue(component.getText());
                        }
                    });
				}
			});
        }

        /**
         * This sets the value of the text field.
         */
        public void setValue(String newValue) {
            this.value = newValue;
            informListenersOfChange();
        }

        /**
         * This method returns the current text stored in the component of this model.
         */
        public String getValue() {
            return this.value;
        }

        /* Listener Handling */
        private void informListenersOfChange() {
            for (TextChangeListener listener: listeners)
                listener.informTextChanged(value);
        }

        public void addTextChangeListener(TextChangeListener listener) {
            listeners.add(listener);
        }

        public void removeTextChangeListener(TextChangeListener listener) {
            listeners.remove(listener);
        }
    }

    private ExtendedJTextFieldModel model;

    public ExtendedJTextField() {
        this("");
    }

    public ExtendedJTextField(String value) {
        this.model = new ExtendedJTextFieldModel(value);
        model.registerOnComponent(this);
    }

    public ExtendedJTextField(ExtendedJTextFieldModel model) {
        this.model = model;
        model.registerOnComponent(this);
    }

    /**
     * Use this method to set a new model to this component.
     */
    public void setModel(ExtendedJTextFieldModel model) {
        this.model = model;
        model.registerOnComponent(this);
    }

    /**
     * This method returns the model of this component.
     */
    public ExtendedJTextFieldModel getModel() {
        return this.model;
    }
}