Add player movement freezing during countdown and winner declaration logic

src/main/java/com/alttd/hunger_games/Main.java

@@ -34,7 +34,7 @@ public final class Main extends JavaPlugin {
 
     private void registerServices() {
         round = Round.createSingletonInstance();
-        roundService = RoundService.createSingletonInstance(round);
+        roundService = RoundService.createSingletonInstance(round, this);
         playerTeleporterService = PlayerTeleporterService.createSingletonInstance();
         playerService = PlayerService.createSingletonInstance(round, roundService, playerTeleporterService);
     }

src/main/java/com/alttd/hunger_games/event_listeners/PlayerMovementListener.java

@@ -0,0 +1,29 @@
+package com.alttd.hunger_games.event_listeners;
+
+import lombok.RequiredArgsConstructor;
+import org.bukkit.Location;
+import org.bukkit.event.EventHandler;
+import org.bukkit.event.Listener;
+import org.bukkit.event.player.PlayerMoveEvent;
+
+import java.util.Set;
+import java.util.UUID;
+
+@RequiredArgsConstructor
+public class PlayerMovementListener implements Listener {
+    private final Set<UUID> uuidSet;
+
+    @EventHandler
+    public void onPlayerMove(PlayerMoveEvent event) {
+        if (!uuidSet.contains(event.getPlayer().getUniqueId())) {
+            return;
+        }
+        Location from = event.getFrom();
+        Location to = event.getTo();
+        //Only freeze movement not rotation or jumping
+        if (from.getBlockX() != to.getBlockX()
+            || from.getBlockZ() != to.getBlockZ()) {
+            event.setTo(from);
+        }
+    }
+}

src/main/java/com/alttd/hunger_games/services/RoundService.java

@@ -1,8 +1,13 @@
 package com.alttd.hunger_games.services;
 
+import com.alttd.hunger_games.Main;
 import com.alttd.hunger_games.data_objects.PLAYER_STATE;
 import com.alttd.hunger_games.data_objects.ROUND_STATE;
+import com.alttd.hunger_games.event_listeners.PlayerMovementListener;
 import lombok.Getter;
+import org.bukkit.Bukkit;
+import org.bukkit.entity.Player;
+import org.bukkit.event.HandlerList;
 
 import java.util.*;
 import java.util.stream.Collectors;
@@ -10,21 +15,24 @@ import java.util.stream.Collectors;
 public class RoundService implements RoundListener {
 
     private static RoundService instance = null;
+    private PlayerMovementListener playerMovementListener;
+    private final Main main;
 
     @Getter
     private ROUND_STATE roundState;
     private final HashMap<UUID, PLAYER_STATE> players = new HashMap<>();
 
-    public static RoundService createSingletonInstance(Round round) {
+    public static RoundService createSingletonInstance(Round round, Main main) {
         if (instance != null) {
             throw new IllegalStateException("RoundService is already initialized.");
         }
-        instance = new RoundService(round);
+        instance = new RoundService(round, main);
         return instance;
     }
 
-    private RoundService(Round round) {
+    private RoundService(Round round, Main main) {
         this.roundState = round.register(this);
+        this.main = main;
     }
 
     public Set<UUID> getPlayers(PLAYER_STATE playerState) {
@@ -36,6 +44,20 @@ public class RoundService implements RoundListener {
 
     protected void setPlayerState(UUID uuid, PLAYER_STATE playerState) {
         players.put(uuid, playerState);
+        if (!roundState.equals(ROUND_STATE.KILL_PHASE) && !roundState.equals(ROUND_STATE.FINALE)) {
+            return;
+        }
+        Set<UUID> uuidSet = getPlayers(PLAYER_STATE.REGISTERED);
+        if (uuidSet.size() != 1) {
+            return;
+        }
+        declareWinner(uuidSet.iterator().next());
+    }
+
+    private void declareWinner(UUID winnerUUID) {
+        Player player = Bukkit.getPlayer(winnerUUID);
+        //TODO message
+        //TODO reset round
     }
 
     protected void clear() {
@@ -49,8 +71,27 @@ public class RoundService implements RoundListener {
     @Override
     public void stateChange(ROUND_STATE roundState) {
         this.roundState = roundState;
+        stopFreeze();
         if (roundState.equals(ROUND_STATE.PLAYER_REGISTRATION)) {
             clear();
         }
+        if (roundState.equals(ROUND_STATE.COUNTDOWN)) {
+            startFreeze();
+        }
+    }
+
+    private void stopFreeze() {
+        if (playerMovementListener == null) {
+            return;
+        }
+        HandlerList.unregisterAll(playerMovementListener);
+        playerMovementListener = null;
+    }
+
+    private void startFreeze() {
+        stopFreeze();
+        Set<UUID> uuidSet = getPlayers(PLAYER_STATE.REGISTERED);
+        playerMovementListener = new PlayerMovementListener(uuidSet);
+        main.getServer().getPluginManager().registerEvents(playerMovementListener, main);
     }
 }