added server side map loading verification

Projekte/battleship/model/src/main/java/pp/battleship/game/server/ServerGameLogic.java

@@ -9,6 +9,7 @@ package pp.battleship.game.server;
 
 import pp.battleship.BattleshipConfig;
 import pp.battleship.message.client.ClientInterpreter;
+import pp.battleship.message.client.ClientMessage;
 import pp.battleship.message.client.MapMessage;
 import pp.battleship.message.client.ShootMessage;
 import pp.battleship.message.server.EffectMessage;
@@ -134,6 +135,7 @@ public class ServerGameLogic implements ClientInterpreter {
 
     /**
      * Handles the reception of a MapMessage.
+     * Also tests if Map is in correct format
      *
      * @param msg  the received MapMessage
      * @param from the ID of the sender client
@@ -142,10 +144,59 @@ public class ServerGameLogic implements ClientInterpreter {
     public void received(MapMessage msg, int from) {
         if (state != ServerState.SET_UP)
             LOGGER.log(Level.ERROR, "playerReady not allowed in {0}", state); //NON-NLS
-        else
-            playerReady(getPlayerById(from), msg.getShips());
+        
+        Player cp = getPlayerById(from);
+        List<Battleship> ships = msg.getShips();
+
+        if (!validateShips(ships)) {
+            LOGGER.log(Level.ERROR, "Invalid ship placement by player {0}", from);
+            return;
         }
 
+        playerReady(cp, ships);
+    }
+
+
+    /**
+     * Validates a list of ships.
+     * Validates the list, that no ships are out of bounds or overlap with each other
+     * 
+     * @param ships list of ships to validate
+     * @return {@code true} if all ships positions are valid, {@code false} otherwise
+     */
+    private boolean validateShips(List<Battleship> ships) {
+        Set<IntPoint> occupiedPoints = new HashSet<>();
+    
+        for (Battleship ship : ships) {
+            if (!isWithinBounds(ship)) {
+                return false;
+            }
+    
+            for (int x = ship.getMinX(); x <= ship.getMaxX(); x++) {
+                for (int y = ship.getMinY(); y <= ship.getMaxY(); y++) {
+                    IntPoint point = new IntPoint(x, y);
+                    if (!occupiedPoints.add(point)) {
+                        return false;
+                    }
+                }
+            }
+        }
+        
+        return true;
+    }
+    
+
+    /**
+     * Test if a ship is inside the map
+     * @param ship the ship to validate
+     * @return {@code true} if a ship is within bounds, {@code false} otherwise
+     */
+    private boolean isWithinBounds(Battleship ship) {
+        return ship.getMinX() >= 0 && ship.getMaxX() < config.getMapWidth() &&
+               ship.getMinY() >= 0 && ship.getMaxY() < config.getMapHeight();
+    }
+    
+
     /**
      * Handles the reception of a ShootMessage.
      *