001/*
002 * JGrapes Event Driven Framework
003 * Copyright (C) 2017-2018 Michael N. Lipp
004 * 
005 * This program is free software; you can redistribute it and/or modify it 
006 * under the terms of the GNU Affero General Public License as published by 
007 * the Free Software Foundation; either version 3 of the License, or 
008 * (at your option) any later version.
009 * 
010 * This program is distributed in the hope that it will be useful, but 
011 * WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
012 * or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Affero General Public License 
013 * for more details.
014 * 
015 * You should have received a copy of the GNU Affero General Public License along 
016 * with this program; if not, see <http://www.gnu.org/licenses/>.
017 */
018
019package org.jgrapes.webconsole.base.events;
020
021import java.util.HashMap;
022import java.util.Map;
023import java.util.function.BiConsumer;
024import org.jdrupes.json.JsonArray;
025import org.jgrapes.core.Event;
026
027/**
028 * Sent to a web console component to update some of its properties. 
029 * The interpretation of the properties is completely dependent on the 
030 * handling web console component.
031 * 
032 * This event has a close relationship to the {@link NotifyConletModel}
033 * event. The latter is used by web console component's functions to 
034 * send information from the console page to the web console component 
035 * model. It passes the information as a {@link JsonArray}. The 
036 * interpretation of this information is only known by the web console 
037 * component. The {@link UpdateConletModel} event should be 
038 * used to to pass information within the application, i.e. on the server
039 * side.
040 * 
041 * Depending on the information passed, it may be good practice to 
042 * write an event handler for the web console component that converts a 
043 * {@link NotifyConletModel} to a {@link UpdateConletModel} that is
044 * fired on its channel instead of handling it immediately. This allows 
045 * events sent from the console page and from other components in the 
046 * application to be handled in a uniform way.
047 */
048public class UpdateConletModel extends Event<Void> {
049
050    private String conletId;
051    private Map<Object, Object> properties;
052
053    /**
054     * Creates a new event.
055     * 
056     * @param conletId the id of the web console component
057     * @param properties the properties to update
058     */
059    public UpdateConletModel(String conletId, Map<?, ?> properties) {
060        this.conletId = conletId;
061        @SuppressWarnings("unchecked")
062        Map<Object, Object> props = (Map<Object, Object>) properties;
063        this.properties = props;
064    }
065
066    /**
067     * Creates a new event. This constructor creates an empty map of
068     * properties and is therefore intended to be used together with
069     * {@link #addPreference(Object, Object)}.
070     *
071     * @param conletId the web console component id
072     */
073    public UpdateConletModel(String conletId) {
074        this(conletId, new HashMap<>());
075    }
076
077    /**
078     * Returns the web console component id.
079     * 
080     * @return the web console component id
081     */
082    public String conletId() {
083        return conletId;
084    }
085
086    /**
087     * Returns the properties. Every event returns a mutable map,
088     * thus allowing event handlers to modify the map even if
089     * none was passed to the constructor.
090     */
091    public Map<Object, Object> properties() {
092        if (properties == null) {
093            properties = new HashMap<>();
094        }
095        return properties;
096    }
097
098    /**
099     * Convenience method for adding properties one-by-one.
100     * 
101     * @param key the property key
102     * @param value the property value
103     * @return the event for easy chaining
104     */
105    public UpdateConletModel addPreference(Object key, Object value) {
106        properties().put(key, value);
107        return this;
108    }
109
110    /**
111     * Convenience method that performs the given action if a property
112     * with the given key exists.
113     * 
114     * @param key the property key
115     * @param action the action to perform
116     */
117    public UpdateConletModel ifPresent(
118            Object key, BiConsumer<Object, Object> action) {
119        if (properties().containsKey(key)) {
120            action.accept(key, properties().get(key));
121        }
122        return this;
123    }
124}