/*******************************************************************************
 * Copyright (c) 2009, 2010 Progress Software Corporation.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 ******************************************************************************/
package org.fusesource.tools.messaging.preference;

import java.util.ArrayList;
import java.util.List;

import org.eclipse.jface.preference.IPreferenceStore;
import org.eclipse.jface.util.IPropertyChangeListener;
import org.eclipse.jface.util.PropertyChangeEvent;
import org.fusesource.tools.messaging.IConstants;
import org.fusesource.tools.messaging.plugin.FuseMessagingPlugin;

public class BasePreferenceHandler implements PreferenceHandler, IPropertyChangeListener {

    private IPreferenceStore store = null;

    private List<PreferenceChangedListener> preferenceChangedListenerList = new ArrayList<PreferenceChangedListener>();

    private static BasePreferenceHandler basePreferenceHandler;

    private BasePreferenceHandler() {
        setPreferenceStore();
        initializeDefaultPreferences();
        store.addPropertyChangeListener(this);
    }

    private void initializeDefaultPreferences() {
        IPreferenceStore preferenceStore = getPreferenceStore();
        preferenceStore.setDefault(IConstants.MESSAGES_HISTORY_COUNT, IConstants.DEFAULT_MESSAGES_HISTORY_COUNT);
    }

    private void setPreferenceStore() {
        store = FuseMessagingPlugin.getDefault().getPreferenceStore();
    }

    public static BasePreferenceHandler getInstance() {
        if (basePreferenceHandler == null) {
            basePreferenceHandler = new BasePreferenceHandler();
        }
        return basePreferenceHandler;
    }

    public void propertyChange(PropertyChangeEvent event) {
        String prefKey = event.getProperty();
        String prefValue = store.getString(prefKey);
        firePreferenceChangedEvent(prefKey, prefValue);
    }

    /**
     * @param event
     */
    public void firePreferenceChangedEvent(String prefKey, Object prefValue) {
        PreferenceEvent event = new PreferenceEvent(prefKey, prefValue);
        for (int i = 0; i < preferenceChangedListenerList.size(); i++) {
            PreferenceChangedListener listener = preferenceChangedListenerList.get(i);
            listener.valueChanged(event);
        }
    }

    public IPreferenceStore getPreferenceStore() {
        return store;
    }

    public void addPreferenceChangedListener(PreferenceChangedListener listener) {
        preferenceChangedListenerList.add(listener);
    }

    public void removePreferenceChangedListener(PreferenceChangedListener listener) {
        preferenceChangedListenerList.remove(listener);
    }

    public String getPreferenceValue(String key) {
        return store.getString(key);
    }

    public void setPreferenceValue(String key, String value) {
        store.setValue(key, value);
    }

}