Add ActionBar functionality for sending messages to players

This commit introduces the ActionBar class along with supporting classes
(ActionBarEntry, ActionBarManager, ActionBarMessage, ActionBarPriority)
to manage and send action bar messages to players in the game. The
ActionBar allows for customizable message duration, repeat intervals,
and priority levels, enhancing the user experience with dynamic
messaging.

Author: BenCodez

SimpleAPI/src/main/java/com/bencodez/simpleapi/messages/actionbar/ActionBar.java

@@ -0,0 +1,188 @@
+package com.bencodez.simpleapi.messages.actionbar;
+
+import org.bukkit.Bukkit;
+import org.bukkit.entity.Player;
+
+import lombok.Getter;
+import lombok.Setter;
+
+/**
+ * Compatibility wrapper for sending action bars.
+ */
+@Getter
+@Setter
+public class ActionBar {
+
+    /**
+     * Action bar manager.
+     */
+    private static ActionBarManager manager;
+
+    /**
+     * Message.
+     */
+    private String msg;
+
+    /**
+     * Duration in ticks.
+     */
+    private long duration;
+
+    /**
+     * Repeat interval in ticks.
+     */
+    private long repeatInterval;
+
+    /**
+     * Priority.
+     */
+    private ActionBarPriority priority;
+
+    /**
+     * Creates a new action bar.
+     *
+     * @param msg the message
+     */
+    public ActionBar(String msg) {
+        this(msg, -1L, -1L, ActionBarPriority.NORMAL);
+    }
+
+    /**
+     * Creates a new action bar.
+     *
+     * @param msg the message
+     * @param duration the duration in ticks
+     */
+    public ActionBar(String msg, long duration) {
+        this(msg, duration, 20L, ActionBarPriority.NORMAL);
+    }
+
+    /**
+     * Creates a new action bar.
+     *
+     * @param msg the message
+     * @param duration the duration in ticks
+     * @param repeatInterval the repeat interval in ticks
+     */
+    public ActionBar(String msg, long duration, long repeatInterval) {
+        this(msg, duration, repeatInterval, ActionBarPriority.NORMAL);
+    }
+
+    /**
+     * Creates a new action bar.
+     *
+     * @param msg the message
+     * @param duration the duration in ticks
+     * @param repeatInterval the repeat interval in ticks
+     * @param priority the priority
+     */
+    public ActionBar(String msg, long duration, long repeatInterval, ActionBarPriority priority) {
+        this.msg = msg;
+        this.duration = duration;
+        this.repeatInterval = repeatInterval;
+        this.priority = priority;
+    }
+
+    /**
+     * Sets the manager used by this API.
+     *
+     * @param manager the manager
+     */
+    public static void setManager(ActionBarManager manager) {
+        ActionBar.manager = manager;
+    }
+
+    /**
+     * Gets the current manager.
+     *
+     * @return the manager
+     */
+    public static ActionBarManager getManager() {
+        return manager;
+    }
+
+    /**
+     * Sends this action bar to players.
+     *
+     * @param players the players
+     */
+    public void send(Player... players) {
+        if (manager == null || players == null) {
+            return;
+        }
+
+        ActionBarMessage message = new ActionBarMessage(msg, duration, repeatInterval, true, priority);
+        for (Player player : players) {
+            manager.send(player, message);
+        }
+    }
+
+    /**
+     * Sends an action bar immediately.
+     *
+     * @param player the player
+     * @param message the message
+     */
+    public void sendActionBar(Player player, String message) {
+        if (manager == null) {
+            return;
+        }
+
+        manager.send(player, new ActionBarMessage(message));
+    }
+
+    /**
+     * Sends an action bar with duration.
+     *
+     * @param player the player
+     * @param message the message
+     * @param duration the duration in ticks
+     */
+    public void sendActionBar(Player player, String message, int duration) {
+        if (manager == null) {
+            return;
+        }
+
+        manager.send(player, new ActionBarMessage(message, duration, 20L, true, ActionBarPriority.NORMAL));
+    }
+
+    /**
+     * Sends an action bar to all online players.
+     *
+     * @param message the message
+     */
+    public void sendActionBarToAllPlayers(String message) {
+        sendActionBarToAllPlayers(message, -1);
+    }
+
+    /**
+     * Sends an action bar to all online players.
+     *
+     * @param message the message
+     * @param duration the duration in ticks
+     */
+    public void sendActionBarToAllPlayers(String message, int duration) {
+        if (manager == null) {
+            return;
+        }
+
+        ActionBarMessage actionBarMessage = new ActionBarMessage(message, duration, 20L, true,
+                ActionBarPriority.NORMAL);
+        for (Player player : Bukkit.getOnlinePlayers()) {
+            manager.send(player, actionBarMessage);
+        }
+    }
+
+    /**
+     * Clears an action bar from a player.
+     *
+     * @param player the player
+     */
+    public static void clear(Player player) {
+        if (manager == null) {
+            return;
+        }
+
+        manager.clear(player);
+    }
+}

SimpleAPI/src/main/java/com/bencodez/simpleapi/messages/actionbar/ActionBarEntry.java

@@ -0,0 +1,55 @@
+package com.bencodez.simpleapi.messages.actionbar;
+
+import java.util.UUID;
+
+import org.bukkit.scheduler.BukkitTask;
+
+import lombok.Getter;
+import lombok.Setter;
+
+/**
+ * Stores the active action bar state for a player.
+ */
+@Getter
+@Setter
+public class ActionBarEntry {
+
+    /**
+     * Player unique id.
+     */
+    private UUID playerUuid;
+
+    /**
+     * Sequence used to prevent older messages from overriding newer ones.
+     */
+    private long sequence;
+
+    /**
+     * Active message.
+     */
+    private ActionBarMessage message;
+
+    /**
+     * Repeating resend task.
+     */
+    private BukkitTask repeatingTask;
+
+    /**
+     * Expiration task.
+     */
+    private BukkitTask expireTask;
+
+    /**
+     * Cancels all scheduled tasks.
+     */
+    public void cancel() {
+        if (repeatingTask != null) {
+            repeatingTask.cancel();
+            repeatingTask = null;
+        }
+        if (expireTask != null) {
+            expireTask.cancel();
+            expireTask = null;
+        }
+    }
+}