Implement greetings listener for messaging

Author: TechnoVisionDev

src/main/java/technobot/TechnoBot.java

@@ -67,7 +67,8 @@ public TechnoBot() throws LoginException {
                 buttonListener,
                 musicListener,
                 new StarboardListener(),
-                new LevelingListener(this));
+                new LevelingListener(this),
+                new GreetingListener());
     }
 
     /**

src/main/java/technobot/data/GuildData.java

@@ -5,7 +5,6 @@
 import org.jetbrains.annotations.NotNull;
 import technobot.TechnoBot;
 import technobot.data.cache.Config;
-import technobot.data.cache.Suggestion;
 import technobot.handlers.*;
 
 import java.util.HashMap;

src/main/java/technobot/handlers/GreetingHandler.java

@@ -50,6 +50,69 @@ public void removeGreet() {
         bot.database.greetings.updateOne(filter, Updates.unset("greeting"));
     }
 
+    /**
+     * Gets the greet message.
+     *
+     * @return string greet message.
+     */
+    public String getGreet() {
+        return greetings.getGreeting();
+    }
+
+    /**
+     * Set a farewell message for this server.
+     *
+     * @param msg the message to send on member leave.
+     */
+    public void setFarewell(String msg) {
+        greetings.setFarewell(msg);
+        bot.database.greetings.updateOne(filter, Updates.set("farewell", msg));
+    }
+
+    /**
+     * Remove farewell message from this server.
+     */
+    public void removeFarewell() {
+        greetings.setGreeting(null);
+        bot.database.greetings.updateOne(filter, Updates.unset("farewell"));
+    }
+
+    /**
+     * Gets the farewell message.
+     *
+     * @return string farewell message.
+     */
+    public String getFarewell() {
+        return greetings.getFarewell();
+    }
+
+    /**
+     * Set a join DM message for this server.
+     *
+     * @param msg the message to send on member leave.
+     */
+    public void setJoinDM(String msg) {
+        greetings.setJoinDM(msg);
+        bot.database.greetings.updateOne(filter, Updates.set("join_dm", msg));
+    }
+
+    /**
+     * Remove join DM message from this server.
+     */
+    public void removeJoinDM() {
+        greetings.setJoinDM(null);
+        bot.database.greetings.updateOne(filter, Updates.unset("join_dm"));
+    }
+
+    /**
+     * Gets the join DM message.
+     *
+     * @return string farewell message.
+     */
+    public String getJoinDM() {
+        return greetings.getJoinDM();
+    }
+
     /**
      * Set the welcome channel.
      *
@@ -68,6 +131,20 @@ public void removeChannel() {
         bot.database.greetings.updateOne(filter, Updates.unset("welcome_channel"));
     }
 
+    /**
+     * Gets the ID of the welcome channel.
+     *
+     * @return long id of the welcome channel.
+     */
+    public Long getChannel() {
+        return greetings.getWelcomeChannel();
+    }
+
+    /**
+     * Getter for greetings config POJO object.
+     *
+     * @return instance of greetings config POJO.
+     */
     public Greetings getConfig() {
         return greetings;
     }

src/main/java/technobot/listeners/GreetingListener.java

@@ -0,0 +1,65 @@
+package technobot.listeners;
+
+import net.dv8tion.jda.api.entities.MessageChannel;
+import net.dv8tion.jda.api.events.guild.member.GuildMemberJoinEvent;
+import net.dv8tion.jda.api.events.guild.member.GuildMemberRemoveEvent;
+import net.dv8tion.jda.api.hooks.ListenerAdapter;
+import org.jetbrains.annotations.NotNull;
+import technobot.data.GuildData;
+import technobot.handlers.GreetingHandler;
+import technobot.util.placeholders.Placeholder;
+import technobot.util.placeholders.PlaceholderFactory;
+
+/**
+ * Listens for member join and leave to manage greetings.
+ *
+ * @author TechnoVision
+ */
+public class GreetingListener extends ListenerAdapter {
+
+    /**
+     * Triggers every time a user joins a guild.
+     * Sends a greeting message to the guild's welcome channel.
+     */
+    @Override
+    public void onGuildMemberJoin(@NotNull GuildMemberJoinEvent event) {
+        GreetingHandler greetingHandler = GuildData.get(event.getGuild()).greetingHandler;
+        // Get welcome channel
+        Long channelID = greetingHandler.getChannel();
+        if (channelID == null) return;
+
+        // Get greet message
+        String message = greetingHandler.getGreet();
+        if (message == null || message.isEmpty()) return;
+
+        // Send greet message
+        Placeholder placeholder = PlaceholderFactory.fromEvent(event).get();
+        MessageChannel channel = event.getGuild().getChannelById(MessageChannel.class, channelID);
+        if (channel != null) {
+            channel.sendMessage(placeholder.parse(message)).queue();
+        }
+
+        // Send join DM message
+        String joinDM = greetingHandler.getJoinDM();
+        if (joinDM != null) {
+            event.getUser().openPrivateChannel().flatMap(dm -> dm.sendMessage(placeholder.parse(joinDM))).queue(null, fail -> { });
+        }
+    }
+
+    /**
+     * Triggers every time a user leaves a guild.
+     * Sends a farewell to the guild's welcome channel.
+     */
+    @Override
+    public void onGuildMemberRemove(@NotNull GuildMemberRemoveEvent event) {
+        GreetingHandler greetingHandler = GuildData.get(event.getGuild()).greetingHandler;
+        if (greetingHandler.getChannel() == null || greetingHandler.getFarewell() == null) return;
+
+        // send farewell message
+        MessageChannel channel = event.getGuild().getChannelById(MessageChannel.class, greetingHandler.getChannel());
+        if (channel != null) {
+            Placeholder placeholder = PlaceholderFactory.fromEvent(event).get();
+            channel.sendMessage(placeholder.parse(greetingHandler.getFarewell())).queue();
+        }
+    }
+}

src/main/java/technobot/util/placeholders/PlaceholderFactory.java

@@ -102,6 +102,8 @@ private static PlaceholderFactory assemble(Placeholder placeholder) {
             placeholder.add("username", user.getAsTag());
             placeholder.add("user_id", user.getId());
             placeholder.add("user_mention", "<@!" + user.getId() + ">");
+            placeholder.add("mention", "<@!" + user.getId() + ">");
+            placeholder.add("avatar", user.getEffectiveAvatarUrl());
             placeholder.add("user_avatar", user.getEffectiveAvatarUrl());
             placeholder.add("user_icon", user.getEffectiveAvatarUrl());
         });
@@ -132,6 +134,8 @@ private static PlaceholderFactory assemble(Placeholder placeholder) {
     @SuppressWarnings("UnusedReturnValue")
     default @NotNull PlaceholderFactory withGuildCapabilities(@NotNull Guild guild) {
         accept(placeholder -> {
+            placeholder.add("server", guild.getName());
+            placeholder.add("guild", guild.getName());
             placeholder.add("guild_name", guild.getName());
             placeholder.add("guild_id", guild.getId());
             placeholder.add("guild_icon", guild.getIconUrl());
@@ -155,6 +159,7 @@ private static PlaceholderFactory assemble(Placeholder placeholder) {
             });
         }
         accept(placeholder -> {
+            placeholder.add("channel", channel.getName());
             placeholder.add("channel_name", channel.getName());
             placeholder.add("channel_id", channel.getId());
             placeholder.add("channel_mention", "<#" + channel.getId() + ">");