Provide new and old topic in event

Author: mbax

src/main/java/org/kitteh/irc/client/library/defaults/listener/DefaultTopicListener.java

@@ -32,20 +32,25 @@
 import org.kitteh.irc.client.library.event.client.ClientReceiveNumericEvent;
 import org.kitteh.irc.client.library.feature.filter.CommandFilter;
 import org.kitteh.irc.client.library.feature.filter.NumericFilter;
+import org.kitteh.irc.client.library.util.CIKeyMap;
 
+import java.util.Map;
 import java.util.Optional;
 
 /**
  * Default TOPIC listener, producing events using default classes.
  */
 public class DefaultTopicListener extends AbstractDefaultListenerBase {
+    private final Map<String, Channel.Topic> oldTopics;
+
     /**
      * Constructs the listener.
      *
      * @param client client
      */
     public DefaultTopicListener(Client.@NonNull WithManagement client) {
         super(client);
+        this.oldTopics = new CIKeyMap<>(client);
     }
 
     @NumericFilter(332) // Topic
@@ -57,7 +62,9 @@ public void topic(ClientReceiveNumericEvent event) {
         }
         Optional<Channel> topicChannel = this.getTracker().getChannel(event.getParameters().get(1));
         if (topicChannel.isPresent()) {
-            this.getTracker().setChannelTopic(topicChannel.get().getName(), event.getParameters().get(2));
+            Channel oldChannel = topicChannel.get();
+            this.oldTopics.put(oldChannel.getName(), oldChannel.getTopic());
+            this.getTracker().setChannelTopic(oldChannel.getName(), event.getParameters().get(2));
         } else {
             this.trackException(event, "Topic message sent for invalid channel name");
         }
@@ -72,8 +79,9 @@ public void topicInfo(ClientReceiveNumericEvent event) {
         }
         Optional<Channel> topicSetChannel = this.getTracker().getChannel(event.getParameters().get(1));
         if (topicSetChannel.isPresent()) {
-            this.getTracker().setChannelTopicInfo(topicSetChannel.get().getName(), Long.parseLong(event.getParameters().get(3)) * 1000, this.getTracker().getActor(event.getParameters().get(2)));
-            this.fire(new ChannelTopicEvent(this.getClient(), event.getSource(), topicSetChannel.get(), false));
+            Channel oldChannel = topicSetChannel.get();
+            this.getTracker().setChannelTopicInfo(oldChannel.getName(), Long.parseLong(event.getParameters().get(3)) * 1000, this.getTracker().getActor(event.getParameters().get(2)));
+            this.fire(new ChannelTopicEvent(this.getClient(), event.getSource(), oldChannel, this.oldTopics.remove(oldChannel.getName()), oldChannel.getLatest().get().getTopic(), false));
         } else {
             this.trackException(event, "Topic message sent for invalid channel name");
         }
@@ -88,9 +96,10 @@ public void topic(ClientReceiveCommandEvent event) {
         }
         Optional<Channel> channel = this.getTracker().getChannel(event.getParameters().get(0));
         if (channel.isPresent()) {
-            this.getTracker().setChannelTopic(channel.get().getName(), event.getParameters().get(1));
-            this.getTracker().setChannelTopicInfo(channel.get().getName(), System.currentTimeMillis(), event.getActor());
-            this.fire(new ChannelTopicEvent(this.getClient(), event.getSource(), channel.get(), true));
+            Channel oldChannel = channel.get();
+            this.getTracker().setChannelTopic(oldChannel.getName(), event.getParameters().get(1));
+            this.getTracker().setChannelTopicInfo(oldChannel.getName(), System.currentTimeMillis(), event.getActor());
+            this.fire(new ChannelTopicEvent(this.getClient(), event.getSource(), oldChannel, oldChannel.getTopic(), oldChannel.getLatest().get().getTopic(), true));
         } else {
             this.trackException(event, "TOPIC message sent for invalid channel name");
         }

src/main/java/org/kitteh/irc/client/library/event/channel/ChannelTopicEvent.java

@@ -37,31 +37,59 @@
  */
 public class ChannelTopicEvent extends ChannelEventBase {
     private final boolean updated;
+    private final Channel.Topic oldTopic;
+    private final Channel.Topic newTopic;
 
     /**
      * Creates the event.
      *
      * @param client client for which this is occurring
      * @param sourceMessage source message
      * @param channel channel the topic is about
+     * @param oldTopic old topic
+     * @param newTopic new topic
      * @param updated if this is a new change
-     * @see Channel#getTopic()
      */
-    public ChannelTopicEvent(@NonNull Client client, @NonNull ServerMessage sourceMessage, @NonNull Channel channel, boolean updated) {
+    public ChannelTopicEvent(@NonNull Client client, @NonNull ServerMessage sourceMessage, @NonNull Channel channel, Channel.@NonNull Topic oldTopic, Channel.@NonNull Topic newTopic, boolean updated) {
         super(client, sourceMessage, channel);
+        this.oldTopic = oldTopic;
+        this.newTopic = newTopic;
         this.updated = updated;
     }
 
+    /**
+     * Creates the event.
+     *
+     * @param client client for which this is occurring
+     * @param sourceMessage source message
+     * @param channel channel the topic is about
+     * @param updated if this is a new change
+     * @deprecated Use new constructor
+     */
+    @Deprecated
+    public ChannelTopicEvent(@NonNull Client client, @NonNull ServerMessage sourceMessage, @NonNull Channel channel, boolean updated) {
+        this(client, sourceMessage, channel, null, null, updated);
+    }
+
     /**
      * Gets the channel's topic.
      *
      * @return the channel topic
-     * @see Channel#getTopic()
+     * @deprecated Use {@link #getNewTopic()} and {@link #getOldTopic()}
      */
+    @Deprecated
     public Channel.@NonNull Topic getTopic() {
         return this.getChannel().getTopic();
     }
 
+    public Channel.@NonNull Topic getNewTopic() {
+        return this.newTopic;
+    }
+
+    public Channel.@NonNull Topic getOldTopic() {
+        return this.oldTopic;
+    }
+
     /**
      * Gets if this is a new topic update, or just the server informing us of
      * a change from the past.