Fixes exploit where players could get duplicate top ten entries

#22

Requires 1.3.0 or later BentoBox because it listens for new events fired
by that version.

pom.xml

@@ -6,7 +6,7 @@
 
 	<groupId>world.bentobox</groupId>
 	<artifactId>level</artifactId>
-	<version>1.2-SNAPSHOT</version>
+	<version>1.2.1-SNAPSHOT</version>
 
 	<name>Level</name>
 	<description>Level is an add-on for BentoBox, an expandable Minecraft Bukkit plugin for island-type games like SkyBlock or AcidIsland.</description>
@@ -86,7 +86,7 @@
 		<dependency>
 			<groupId>world.bentobox</groupId>
 			<artifactId>bentobox</artifactId>
-			<version>1.1-SNAPSHOT</version>
+			<version>1.3.0-SNAPSHOT</version>
 			<scope>provided</scope>
 		</dependency>
 	</dependencies>

src/main/java/world/bentobox/level/Level.java

@@ -16,7 +16,7 @@
 import world.bentobox.level.commands.island.IslandTopCommand;
 import world.bentobox.level.config.Settings;
 import world.bentobox.level.listeners.JoinLeaveListener;
-import world.bentobox.level.listeners.NewIslandListener;
+import world.bentobox.level.listeners.IslandTeamListeners;
 import world.bentobox.level.objects.LevelsData;
 import world.bentobox.level.placeholders.LevelPlaceholder;
 import world.bentobox.level.requests.LevelRequestHandler;
@@ -133,7 +133,7 @@ public void onEnable() {
         });
 
         // Register new island listener
-        registerListener(new NewIslandListener(this));
+        registerListener(new IslandTeamListeners(this));
         registerListener(new JoinLeaveListener(this));
 
         // Register request handlers

src/main/java/world/bentobox/level/listeners/IslandTeamListeners.java

@@ -0,0 +1,102 @@
+package world.bentobox.level.listeners;
+
+import java.util.HashMap;
+import java.util.Map;
+
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.EventPriority;
+import org.bukkit.event.Listener;
+
+import world.bentobox.bentobox.api.events.island.IslandEvent.IslandCreatedEvent;
+import world.bentobox.bentobox.api.events.island.IslandEvent.IslandRegisteredEvent;
+import world.bentobox.bentobox.api.events.island.IslandEvent.IslandResettedEvent;
+import world.bentobox.bentobox.api.events.island.IslandEvent.IslandUnregisteredEvent;
+import world.bentobox.bentobox.api.events.team.TeamEvent.TeamJoinedEvent;
+import world.bentobox.bentobox.api.events.team.TeamEvent.TeamKickEvent;
+import world.bentobox.bentobox.api.events.team.TeamEvent.TeamLeaveEvent;
+import world.bentobox.bentobox.api.events.team.TeamEvent.TeamSetownerEvent;
+import world.bentobox.bentobox.database.objects.Island;
+import world.bentobox.level.Level;
+import world.bentobox.level.calculators.CalcIslandLevel;
+
+/**
+ * Listens for new islands or ownership changes and sets the level to zero automatically
+ * @author tastybento
+ *
+ */
+public class IslandTeamListeners implements Listener {
+
+    private final Level addon;
+    private final Map<Island, CalcIslandLevel> cil;
+
+    /**
+     * @param addon - addon
+     */
+    public IslandTeamListeners(Level addon) {
+        this.addon = addon;
+        cil = new HashMap<>();
+    }
+
+    @EventHandler(priority = EventPriority.NORMAL, ignoreCancelled = true)
+    public void onNewIsland(IslandCreatedEvent e) {
+        if (e.getIsland().getOwner() != null && e.getIsland().getWorld() != null) {
+            cil.putIfAbsent(e.getIsland(), new CalcIslandLevel(addon, e.getIsland(), () -> zeroLevel(e.getIsland())));
+        }
+    }
+
+    @EventHandler(priority = EventPriority.NORMAL, ignoreCancelled = true)
+    public void onNewIsland(IslandResettedEvent e) {
+        if (e.getIsland().getOwner() != null && e.getIsland().getWorld() != null) {
+            cil.putIfAbsent(e.getIsland(), new CalcIslandLevel(addon, e.getIsland(), () -> zeroLevel(e.getIsland())));
+        }
+    }
+
+    @EventHandler(priority = EventPriority.NORMAL, ignoreCancelled = true)
+    public void onNewIslandOwner(TeamSetownerEvent e) {
+        // Remove player from the top ten and level
+        addon.setIslandLevel(e.getIsland().getWorld(), e.getIsland().getOwner(), 0);
+        addon.getTopTen().removeEntry(e.getIsland().getWorld(), e.getIsland().getOwner());
+    }
+
+    @EventHandler(priority = EventPriority.NORMAL, ignoreCancelled = true)
+    public void onIsland(TeamJoinedEvent e) {
+        // Remove player from the top ten and level
+        addon.setIslandLevel(e.getIsland().getWorld(), e.getPlayerUUID(), 0);
+        addon.getTopTen().removeEntry(e.getIsland().getWorld(), e.getPlayerUUID());
+    }
+
+    @EventHandler(priority = EventPriority.NORMAL, ignoreCancelled = true)
+    public void onIsland(IslandUnregisteredEvent e) {
+        // Remove player from the top ten and level
+        addon.setIslandLevel(e.getIsland().getWorld(), e.getPlayerUUID(), 0);
+        addon.getTopTen().removeEntry(e.getIsland().getWorld(), e.getPlayerUUID());
+    }
+
+    @EventHandler(priority = EventPriority.NORMAL, ignoreCancelled = true)
+    public void onIsland(IslandRegisteredEvent e) {
+        // Remove player from the top ten and level
+        addon.setIslandLevel(e.getIsland().getWorld(), e.getPlayerUUID(), 0);
+        addon.getTopTen().removeEntry(e.getIsland().getWorld(), e.getPlayerUUID());
+    }
+
+    @EventHandler(priority = EventPriority.NORMAL, ignoreCancelled = true)
+    public void onIsland(TeamLeaveEvent e) {
+        // Remove player from the top ten and level
+        addon.setIslandLevel(e.getIsland().getWorld(), e.getPlayerUUID(), 0);
+        addon.getTopTen().removeEntry(e.getIsland().getWorld(), e.getPlayerUUID());
+    }
+
+    @EventHandler(priority = EventPriority.NORMAL, ignoreCancelled = true)
+    public void onIsland(TeamKickEvent e) {
+        // Remove player from the top ten and level
+        addon.setIslandLevel(e.getIsland().getWorld(), e.getPlayerUUID(), 0);
+        addon.getTopTen().removeEntry(e.getIsland().getWorld(), e.getPlayerUUID());
+    }
+
+    private void zeroLevel(Island island) {
+        if (cil.containsKey(island)) {
+            addon.setInitialIslandLevel(island, cil.get(island).getResult().getLevel());
+            cil.remove(island);
+        }
+    }
+}