#34: create a staff chat event for the velocity plugin

README.md

@@ -93,3 +93,45 @@ Register the listener with
 getProxy().getPluginManager().registerListener(this, new StaffChatListener());
 ```
 in your plugin onEnable.
+
+### Velocity
+
+```java
+public class StaffChatListener {
+
+  @Subscribe
+  public void onStaffChat(VelocityStaffChatEvent event) {
+    // Player player = event.getPlayer();
+    // String format = event.getFormat();
+    // String message = event.getMessage();
+    // StaffChatResult result = StaffChatResult.denied();
+    // StaffChatResult result = StaffChatResult.format("&b{NAME} >> {MESSAGE}");
+    // StaffChatResult result = StaffChatResult.message(filterMessage(message));
+    // StaffChatResult result = StaffChatResult.formatAndMessage("&b{NAME} >> {MESSAGE}", filterMessage(message));
+    // event.setResult(result);
+  }
+
+  private static String filterMessage(String message) {
+    // ...
+    return message;
+  }
+}
+```
+Register the listener on the `ProxyInitializeEvent` in your plugin.
+```java
+@Plugin
+public class Plugin {
+
+  private final ProxyServer server;
+
+  @Inject
+  public Plugin(ProxyServer server) {
+    this.server = server;
+  }
+
+  @Subscribe
+  public void onProxyInitialization(ProxyInitializeEvent event) {
+    server.getEventManager().register(this, new StaffChatListener());
+  }
+}
+```

src/velocity/java/me/oskar3123/staffchat/velocity/event/VelocityStaffChatEvent.java

@@ -0,0 +1,260 @@
+package me.oskar3123.staffchat.velocity.event;
+
+import com.velocitypowered.api.event.ResultedEvent;
+import com.velocitypowered.api.proxy.Player;
+import java.util.Objects;
+import java.util.Optional;
+import java.util.StringJoiner;
+import me.oskar3123.staffchat.velocity.event.VelocityStaffChatEvent.StaffChatResult;
+import org.jetbrains.annotations.Contract;
+import org.jetbrains.annotations.NotNull;
+
+/**
+ * Event fired after deciding to broadcast a staff message.
+ *
+ * <p>Denying this event will still block the chat message.
+ */
+public class VelocityStaffChatEvent implements ResultedEvent<StaffChatResult> {
+
+  private final Player player;
+  private final String format;
+  private final String message;
+
+  private StaffChatResult result = StaffChatResult.allowed();
+
+  @Contract(pure = true)
+  public VelocityStaffChatEvent(
+      @NotNull Player player, @NotNull String format, @NotNull String message) {
+    this.player = Objects.requireNonNull(player, "player must not be null");
+    this.format = Objects.requireNonNull(format, "format must not be null");
+    this.message = Objects.requireNonNull(message, "message must not be null");
+  }
+
+  /**
+   * Gets the player that is sending the staff chat message.
+   *
+   * @return the player
+   */
+  @NotNull
+  @Contract(pure = true)
+  public Player getPlayer() {
+    return player;
+  }
+
+  /**
+   * Gets the initial format decided by the plugin.
+   *
+   * <p>Use {@link #getResult()} to get the potentially modified format.
+   *
+   * @return the initial format
+   */
+  @NotNull
+  @Contract(pure = true)
+  public String getFormat() {
+    return format;
+  }
+
+  /**
+   * Gets the initial message entered by the player.
+   *
+   * <p>Use {@link #getResult()} to get the potentially modified message.
+   *
+   * @return the initial message
+   */
+  @NotNull
+  @Contract(pure = true)
+  public String getMessage() {
+    return message;
+  }
+
+  /**
+   * Gets the current result.
+   *
+   * <p>This will by default be an allowed result with no modifications.
+   *
+   * @return the current result
+   */
+  @NotNull
+  @Contract(pure = true)
+  @Override
+  public StaffChatResult getResult() {
+    return result;
+  }
+
+  /**
+   * Sets the current result.
+   *
+   * <p>You can {@linkplain StaffChatResult#allowed() allow}, {@linkplain StaffChatResult#denied()
+   * deny}, {@linkplain StaffChatResult#format(String) modify the format}, {@linkplain
+   * StaffChatResult#message(String) modify the message}, or {@linkplain
+   * StaffChatResult#formatAndMessage(String, String) modify both the format and message}.
+   *
+   * @param result the new result
+   */
+  @Override
+  public void setResult(@NotNull StaffChatResult result) {
+    this.result = Objects.requireNonNull(result, "result must not be null");
+  }
+
+  @Override
+  public boolean equals(Object o) {
+    if (o == null || getClass() != o.getClass()) return false;
+    VelocityStaffChatEvent that = (VelocityStaffChatEvent) o;
+    return Objects.equals(player, that.player)
+        && Objects.equals(format, that.format)
+        && Objects.equals(message, that.message)
+        && Objects.equals(result, that.result);
+  }
+
+  @Override
+  public int hashCode() {
+    return Objects.hash(player, format, message, result);
+  }
+
+  @Override
+  public String toString() {
+    return new StringJoiner(", ", VelocityStaffChatEvent.class.getSimpleName() + "[", "]")
+        .add("player=" + player)
+        .add("format='" + format + "'")
+        .add("message='" + message + "'")
+        .add("result=" + result)
+        .toString();
+  }
+
+  /** Result of the {@linkplain VelocityStaffChatEvent}. */
+  public static class StaffChatResult implements Result {
+
+    private static final StaffChatResult ALLOWED = new StaffChatResult(true, null, null);
+    private static final StaffChatResult DENIED = new StaffChatResult(false, null, null);
+
+    private final boolean allowed;
+    private final String format;
+    private final String message;
+
+    private StaffChatResult(boolean allowed, String format, String message) {
+      this.allowed = allowed;
+      this.format = format;
+      this.message = message;
+    }
+
+    /**
+     * Allows the message to be sent, without modifying anything.
+     *
+     * @return the allowed result
+     */
+    @NotNull
+    @Contract(pure = true)
+    public static StaffChatResult allowed() {
+      return ALLOWED;
+    }
+
+    /**
+     * Prevents the message from being sent.
+     *
+     * @return the denied result
+     */
+    @NotNull
+    @Contract(pure = true)
+    public static StaffChatResult denied() {
+      return DENIED;
+    }
+
+    /**
+     * Allows the message to be sent, modifying the format.
+     *
+     * @param format the format
+     * @return the modify format result
+     */
+    @NotNull
+    @Contract(value = "_ -> new", pure = true)
+    public static StaffChatResult format(@NotNull String format) {
+      return new StaffChatResult(
+          true, Objects.requireNonNull(format, "format must not be null"), null);
+    }
+
+    /**
+     * Allows the message to be sent, modifying the message.
+     *
+     * @param message the message
+     * @return the modify message result
+     */
+    @NotNull
+    @Contract(value = "_ -> new", pure = true)
+    public static StaffChatResult message(@NotNull String message) {
+      return new StaffChatResult(
+          true, null, Objects.requireNonNull(message, "message must not be null"));
+    }
+
+    /**
+     * Allows the message to be sent, modifying the format and message.
+     *
+     * @param format the format
+     * @param message the message
+     * @return the modify format and message result
+     */
+    @NotNull
+    @Contract(value = "_, _ -> new", pure = true)
+    public static StaffChatResult formatAndMessage(
+        @NotNull String format, @NotNull String message) {
+      return new StaffChatResult(
+          true,
+          Objects.requireNonNull(format, "format must not be null"),
+          Objects.requireNonNull(message, "message must not be null"));
+    }
+
+    @Contract(pure = true)
+    @Override
+    public boolean isAllowed() {
+      return allowed;
+    }
+
+    /**
+     * Gets the potentially modified format.
+     *
+     * <p>An empty optional means that the format has not been modified.
+     *
+     * @return the potentially modified format
+     */
+    @NotNull
+    @Contract(pure = true)
+    public Optional<String> getFormat() {
+      return Optional.ofNullable(format);
+    }
+
+    /**
+     * Gets the potentially modified message.
+     *
+     * <p>An empty optional means that the message has not been modified.
+     *
+     * @return the potentially modified message
+     */
+    @NotNull
+    @Contract(pure = true)
+    public Optional<String> getMessage() {
+      return Optional.ofNullable(message);
+    }
+
+    @Override
+    public boolean equals(Object o) {
+      if (o == null || getClass() != o.getClass()) return false;
+      StaffChatResult that = (StaffChatResult) o;
+      return allowed == that.allowed
+          && Objects.equals(format, that.format)
+          && Objects.equals(message, that.message);
+    }
+
+    @Override
+    public int hashCode() {
+      return Objects.hash(allowed, format, message);
+    }
+
+    @Override
+    public String toString() {
+      return new StringJoiner(", ", StaffChatResult.class.getSimpleName() + "[", "]")
+          .add("allowed=" + allowed)
+          .add("format='" + format + "'")
+          .add("message='" + message + "'")
+          .toString();
+    }
+  }
+}

src/velocity/java/me/oskar3123/staffchat/velocity/handler/VelocityStaffChatHandler.java

@@ -8,6 +8,8 @@ import java.util.function.Function;
 import me.oskar3123.staffchat.util.FormatUtils;
 import me.oskar3123.staffchat.util.Permissions;
 import me.oskar3123.staffchat.velocity.VelocityStaffChat;
+import me.oskar3123.staffchat.velocity.event.VelocityStaffChatEvent;
+import me.oskar3123.staffchat.velocity.event.VelocityStaffChatEvent.StaffChatResult;
 import net.kyori.adventure.text.TextComponent;
 import net.kyori.adventure.text.serializer.legacy.LegacyComponentSerializer;
 
@@ -35,11 +37,31 @@ public class VelocityStaffChatHandler {
     }
   }
 
-  public void broadcastStaffMessage(Player sender, String message) {
+  public void broadcastStaffMessage(Player player, String message) {
     String format = plugin.getConfig().node("settings", "format").getString("&b{NAME}: {MESSAGE}");
 
+    plugin
+        .getServer()
+        .getEventManager()
+        .fire(new VelocityStaffChatEvent(player, format, message))
+        .thenAccept(
+            staffChatEvent -> {
+              StaffChatResult result = staffChatEvent.getResult();
+
+              if (result.isAllowed()) {
+                plugin
+                    .getStaffChatHandler()
+                    .broadcastStaffMessage(
+                        player,
+                        result.getFormat().orElse(format),
+                        result.getMessage().orElse(message));
+              }
+            });
+  }
+
+  private void broadcastStaffMessage(Player player, String format, String message) {
     String formattedMessage =
-        FormatUtils.replacePlaceholders(format, Function.identity(), sender::getUsername, message);
+        FormatUtils.replacePlaceholders(format, Function.identity(), player::getUsername, message);
 
     TextComponent component =
         LegacyComponentSerializer.legacyAmpersand().deserialize(formattedMessage);