Added: Specific Error Display

src/main/java/it/polimi/ingsw/gc14/ClientLauncherTUI.java

@@ -78,10 +78,12 @@ public class ClientLauncherTUI {
             }
             System.setProperty("java.rmi.server.hostname", myIP);
             RMIClient client = new RMIClient(controller, IP, 1099, myIP);
-            if (client.connect(username, proposedNumPlayers)) {
+            ErrorType serverResponse=client.connect(username, proposedNumPlayers);
+            if (serverResponse==null) {
                 System.out.println("Succesfully connected to RMI server\n\n");
             } else {
                 System.out.println("RMI connection refused\n\n");
+                controller.view.showError(serverResponse);
                 return;
             }
             controller.setClient(client);
@@ -92,10 +94,12 @@ public class ClientLauncherTUI {
         } else if (networkType == 1) {
             // Connect
             TCPClient client = new TCPClient(controller, IP, 8080,8081);
-            if (client.connect(username, proposedNumPlayers)) {
+            ErrorType serverResponse=client.connect(username, proposedNumPlayers);
+            if (serverResponse==null) {
                 System.out.println("Succesfully connected to TCP server\n\n");
             } else {
                 System.out.println("TCP connection refused\n\n");
+                controller.view.showError(serverResponse);
                 return;
             }
             controller.setClient(client);
@@ -154,7 +158,7 @@ public class ClientLauncherTUI {
                     System.out.println("Insert the required position:");
                     pos = scanner.nextInt();
                 } catch (Exception e) {
-                    view.showError("ERROR: Invalid input(expected number)");
+                    view.showMessage("ERROR: Invalid input(expected number)");
                     return;
                 }
             }
@@ -178,7 +182,7 @@ public class ClientLauncherTUI {
         }
         else
         {
-            view.showError("ERROR: Invalid input(action not valid)");
+            view.showMessage("ERROR: Invalid input(action not valid)");
         }
     }
 

src/main/java/it/polimi/ingsw/gc14/Controller/ClientController.java

@@ -68,14 +68,6 @@ public class ClientController {
         this.myUsername = username;
     }
 
-    /**
-     * Displays an error message in the view.
-     *
-     * @param message the error message to display.
-     */
-    public void onError(String message) {
-        view.showError(message);
-    }
 
     /**
      * Requests to draw a tribe card from the upper list.

src/main/java/it/polimi/ingsw/gc14/ErrorType.java

@@ -1,5 +1,5 @@
 package it.polimi.ingsw.gc14;
 
 public enum ErrorType {
-    USERNAME_ALREADY_EXISTS,WRONG_PLAYER_NUMBER,WRONG_GAME_ACTION,SERVER_CRASHED
+    USER_NOT_FOUND, USERNAME_ALREADY_USED,USER_ALREADY_CONNECTED,WRONG_PLAYER_NUMBER,WRONG_GAME_ACTION,SERVER_CRASHED,GENERIC_ERROR, GAME_ALREADY_STARTED
 }

src/main/java/it/polimi/ingsw/gc14/Network/IClient.java

@@ -1,5 +1,7 @@
 package it.polimi.ingsw.gc14.Network;
 
+import it.polimi.ingsw.gc14.ErrorType;
+
 /**
  * Defines the operations that a client can request during the game.
  */
@@ -14,7 +16,7 @@ public interface IClient {
      * @return {@code true} if the connection is established successfully,
      *         {@code false} otherwise.
      */
-    boolean connect(String username, int preferredInt);
+    ErrorType connect(String username, int preferredInt);
 
     /**
      * Requests to draw a tribe card from the upper tribe card list.

src/main/java/it/polimi/ingsw/gc14/Network/NetworkEvent.java

@@ -1,6 +1,7 @@
 package it.polimi.ingsw.gc14.Network;
 
 import it.polimi.ingsw.gc14.Controller.GameController;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Model.GamePackage.CurrentState;
 import it.polimi.ingsw.gc14.Model.MiniModel;
 import it.polimi.ingsw.gc14.Model.OrderLogicCard;
@@ -21,6 +22,11 @@ import java.util.Map;
  */
 public abstract class NetworkEvent implements Serializable {
 
+    protected ErrorType errorType;
+
+    public ErrorType getErrorType() {
+        return errorType;
+    }
     /**
      * Username of the player requesting the event.
      */
@@ -120,10 +126,11 @@ public abstract class NetworkEvent implements Serializable {
      * @param isError {@code true} if the event represents an error,
      *                {@code false} otherwise.
      */
-    protected NetworkEvent(String username, EventType eventType, boolean isError) {
+    protected NetworkEvent(String username, EventType eventType, boolean isError,ErrorType errorType) {
         this.username = username;
         this.eventType = eventType;
         this.isError = isError;
+        this.errorType = errorType;
     }
 
     /**

src/main/java/it/polimi/ingsw/gc14/Network/NetworkEvents/AddPlayer.java

@@ -1,6 +1,7 @@
 package it.polimi.ingsw.gc14.Network.NetworkEvents;
 
 import it.polimi.ingsw.gc14.Controller.GameController;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Model.MiniModel;
 import it.polimi.ingsw.gc14.Network.EventType;
 import it.polimi.ingsw.gc14.Network.NetworkEvent;
@@ -14,6 +15,10 @@ import java.io.Serializable;
 public class AddPlayer extends NetworkEvent implements  Serializable {
     /** Number of proposed players to add to the match */
     private int proposedNPlayer;
+    public void setErrorType(ErrorType errorType)
+    {
+        this.errorType = errorType;
+    }
 
     /**
      * @return the number of proposed players to add to the match
@@ -29,7 +34,7 @@ public class AddPlayer extends NetworkEvent implements  Serializable {
      * @param proposedNPlayer the number of proposed players to add to the match
      */
     public AddPlayer(String username, int proposedNPlayer) {
-        super(username, EventType.ADD_PLAYER, false);
+        super(username, EventType.ADD_PLAYER, false, ErrorType.GENERIC_ERROR);
         this.proposedNPlayer = proposedNPlayer;
     }
 

src/main/java/it/polimi/ingsw/gc14/Network/NetworkEvents/ApplyNextRound.java

@@ -1,6 +1,7 @@
 package it.polimi.ingsw.gc14.Network.NetworkEvents;
 
 import it.polimi.ingsw.gc14.Controller.GameController;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Model.Cards.BuildingCard;
 import it.polimi.ingsw.gc14.Model.Cards.TribeCard;
 import it.polimi.ingsw.gc14.Model.GamePackage.CurrentState;
@@ -38,7 +39,7 @@ public class ApplyNextRound extends NetworkEvent implements  Serializable{
      * @param players the list of players in the game.
      */
     public ApplyNextRound(Map<Slot, Player> slotPlayerMap, OrderLogicCard orderLogicCard, CurrentState currentState, List<Player> players, ArrayList<TribeCard> upperListTribeCards, ArrayList<TribeCard>lowerListTribeCards, ArrayList<BuildingCard> upperListBuildingCards, ArrayList<BuildingCard>lowerListBuildingCards) {
-        super("SERVER",EventType.NEXT_ROUND,false);
+        super("SERVER",EventType.NEXT_ROUND,false, ErrorType.WRONG_GAME_ACTION);
         this.upperListBuildingCards = upperListBuildingCards;
         this.lowerListBuildingCards = lowerListBuildingCards;
         this.upperListTribeCards = upperListTribeCards;

src/main/java/it/polimi/ingsw/gc14/Network/NetworkEvents/DisconnectedPlayer.java

@@ -1,6 +1,7 @@
 package it.polimi.ingsw.gc14.Network.NetworkEvents;
 
 import it.polimi.ingsw.gc14.Controller.GameController;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Model.MiniModel;
 import it.polimi.ingsw.gc14.Network.EventType;
 import it.polimi.ingsw.gc14.Network.NetworkEvent;
@@ -18,7 +19,7 @@ public class DisconnectedPlayer extends NetworkEvent implements  Serializable{
      * @param username the name of the player requesting the event
      */
     public DisconnectedPlayer(String username){
-        super(username, EventType.DISCONNECTED_PLAYER, false);
+        super(username, EventType.DISCONNECTED_PLAYER, false, ErrorType.GENERIC_ERROR);
     }
 
     /**

src/main/java/it/polimi/ingsw/gc14/Network/NetworkEvents/DrawLowerBuildingCard.java

@@ -1,6 +1,7 @@
 package it.polimi.ingsw.gc14.Network.NetworkEvents;
 
 import it.polimi.ingsw.gc14.Controller.GameController;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Model.MiniModel;
 import it.polimi.ingsw.gc14.Network.EventType;
 import it.polimi.ingsw.gc14.Network.NetworkEvent;
@@ -22,7 +23,7 @@ public class DrawLowerBuildingCard extends NetworkEvent implements  Serializable
      * @param pos the index of the card to draw
      */
     public DrawLowerBuildingCard(String username, int pos){
-        super(username, EventType.DRAW_LOWER_BUILD, false);
+        super(username, EventType.DRAW_LOWER_BUILD, false, ErrorType.WRONG_GAME_ACTION);
         this.pos = pos;
     }
 

src/main/java/it/polimi/ingsw/gc14/Network/NetworkEvents/DrawLowerTribeCard.java

@@ -1,6 +1,7 @@
 package it.polimi.ingsw.gc14.Network.NetworkEvents;
 
 import it.polimi.ingsw.gc14.Controller.GameController;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Model.MiniModel;
 import it.polimi.ingsw.gc14.Network.EventType;
 import it.polimi.ingsw.gc14.Network.NetworkEvent;
@@ -23,7 +24,7 @@ public class DrawLowerTribeCard extends NetworkEvent implements  Serializable{
      * @param pos the index of the card to draw
      */
     public DrawLowerTribeCard(String username, int pos){
-        super(username, EventType.DRAW_LOWER_TRIBE, false);
+        super(username, EventType.DRAW_LOWER_TRIBE, false, ErrorType.WRONG_GAME_ACTION);
         this.pos = pos;
     }
 

src/main/java/it/polimi/ingsw/gc14/Network/NetworkEvents/DrawUpperBuildingCard.java

@@ -1,6 +1,7 @@
 package it.polimi.ingsw.gc14.Network.NetworkEvents;
 
 import it.polimi.ingsw.gc14.Controller.GameController;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Model.MiniModel;
 import it.polimi.ingsw.gc14.Network.EventType;
 import it.polimi.ingsw.gc14.Network.NetworkEvent;
@@ -23,7 +24,7 @@ public class DrawUpperBuildingCard extends NetworkEvent implements  Serializable
      * @param pos the index of the card to draw
      */
     public DrawUpperBuildingCard(String username, int pos){
-        super(username, EventType.DRAW_UPPER_BUILD, false);
+        super(username, EventType.DRAW_UPPER_BUILD, false, ErrorType.WRONG_GAME_ACTION);
         this.pos = pos;
     }
 

src/main/java/it/polimi/ingsw/gc14/Network/NetworkEvents/DrawUpperTribeCard.java

@@ -1,6 +1,7 @@
 package it.polimi.ingsw.gc14.Network.NetworkEvents;
 
 import it.polimi.ingsw.gc14.Controller.GameController;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Model.MiniModel;
 import it.polimi.ingsw.gc14.Network.EventType;
 import it.polimi.ingsw.gc14.Network.NetworkEvent;
@@ -23,7 +24,7 @@ public class DrawUpperTribeCard extends NetworkEvent implements  Serializable{
      * @param pos the index of the card to draw
      */
     public DrawUpperTribeCard(String username, int pos){
-        super(username, EventType.DRAW_UPPER_TRIBE, false);
+        super(username, EventType.DRAW_UPPER_TRIBE, false, ErrorType.WRONG_GAME_ACTION);
         this.pos = pos;
     }
 

src/main/java/it/polimi/ingsw/gc14/Network/NetworkEvents/EndedGame.java

@@ -1,6 +1,7 @@
 package it.polimi.ingsw.gc14.Network.NetworkEvents;
 
 import it.polimi.ingsw.gc14.Controller.GameController;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Model.GamePackage.CurrentState;
 import it.polimi.ingsw.gc14.Model.MiniModel;
 import it.polimi.ingsw.gc14.Model.OrderLogicCard;
@@ -31,7 +32,7 @@ public class EndedGame extends NetworkEvent implements  Serializable{
      * @param players the list of players at the end of the game.
      */
     public EndedGame(Map<Slot, Player> slotPlayerMap, OrderLogicCard orderLogicCard, CurrentState currentState, ArrayList<Player> players){
-        super("SERVER",EventType.ENDED_GAME,false);
+        super("SERVER",EventType.ENDED_GAME,false, ErrorType.GENERIC_ERROR);
         this.slotPlayerMap = slotPlayerMap;
         this.orderLogicCard = orderLogicCard;
         this.currentState = currentState;

src/main/java/it/polimi/ingsw/gc14/Network/NetworkEvents/ReconnectPlayer.java

@@ -1,6 +1,7 @@
 package it.polimi.ingsw.gc14.Network.NetworkEvents;
 
 import it.polimi.ingsw.gc14.Controller.GameController;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Model.MiniModel;
 import it.polimi.ingsw.gc14.Network.EventType;
 import it.polimi.ingsw.gc14.Network.NetworkEvent;
@@ -18,7 +19,7 @@ public class ReconnectPlayer extends NetworkEvent implements Serializable {
      * @param username the username of the player who reconnected.
      */
     public ReconnectPlayer(String username) {
-        super(username, EventType.RECONNECT_PLAYER, false);
+        super(username, EventType.RECONNECT_PLAYER, false, ErrorType.GENERIC_ERROR);
     }
 
     /**

src/main/java/it/polimi/ingsw/gc14/Network/NetworkEvents/SkipTurn.java

@@ -1,6 +1,7 @@
 package it.polimi.ingsw.gc14.Network.NetworkEvents;
 
 import it.polimi.ingsw.gc14.Controller.GameController;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Model.MiniModel;
 import it.polimi.ingsw.gc14.Network.EventType;
 import it.polimi.ingsw.gc14.Network.NetworkEvent;
@@ -18,7 +19,7 @@ public class SkipTurn extends NetworkEvent implements  Serializable{
      * @param username the name of the player requesting the event
      */
     public SkipTurn(String username){
-        super(username, EventType.SKIP_TURN, false);
+        super(username, EventType.SKIP_TURN, false, ErrorType.WRONG_GAME_ACTION);
     }
 
     /**

src/main/java/it/polimi/ingsw/gc14/Network/NetworkEvents/SlotChoice.java

@@ -1,6 +1,7 @@
 package it.polimi.ingsw.gc14.Network.NetworkEvents;
 
 import it.polimi.ingsw.gc14.Controller.GameController;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Model.MiniModel;
 import it.polimi.ingsw.gc14.Network.EventType;
 import it.polimi.ingsw.gc14.Network.NetworkEvent;
@@ -23,7 +24,7 @@ public class SlotChoice extends NetworkEvent implements  Serializable {
      * @param pos the index of the card to draw
      */
     public SlotChoice(String username, int pos) {
-        super(username, EventType.SLOT_CHOICE, false);
+        super(username, EventType.SLOT_CHOICE, false, ErrorType.WRONG_GAME_ACTION);
         this.pos = pos;
     }
 

src/main/java/it/polimi/ingsw/gc14/Network/NetworkEvents/TotemChoice.java

@@ -1,6 +1,7 @@
 package it.polimi.ingsw.gc14.Network.NetworkEvents;
 
 import it.polimi.ingsw.gc14.Controller.GameController;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Model.MiniModel;
 import it.polimi.ingsw.gc14.Model.Totems;
 import it.polimi.ingsw.gc14.Network.EventType;
@@ -40,7 +41,7 @@ public class TotemChoice extends NetworkEvent implements Serializable {
      * @param totem    the name of the selected totem.
      */
     public TotemChoice(String username, String totem) {
-        super(username, EventType.TOTEM_CHOICE, false);
+        super(username, EventType.TOTEM_CHOICE, false, ErrorType.WRONG_GAME_ACTION);
         this.totem = totem;
     }
 

src/main/java/it/polimi/ingsw/gc14/Network/RMI/Client/ClientCallbackImpl.java

@@ -55,7 +55,7 @@ public class ClientCallbackImpl extends UnicastRemoteObject implements IClientCa
     @Override
     public void onAction(NetworkEvent event) throws RemoteException {
         if(event.getIsError()) {
-            clientController.view.showError(event.toString());
+            clientController.view.showError(event.getErrorType());
         } else {
             event.apply(clientController.miniModel);
             clientController.view.render();

src/main/java/it/polimi/ingsw/gc14/Network/RMI/Client/RMIClient.java

@@ -5,6 +5,7 @@ import java.rmi.registry.Registry;
 import java.util.concurrent.*;
 
 import it.polimi.ingsw.gc14.Controller.ClientController;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Network.IClient;
 import it.polimi.ingsw.gc14.Network.NetworkEvents.*;
 import it.polimi.ingsw.gc14.Network.RMI.Common.IGameServer;
@@ -53,7 +54,7 @@ public class RMIClient  implements IClient {
      * opening a second socket).
      */
     @Override
-    public boolean connect(String username, int preferredInt) {
+        public ErrorType connect(String username, int preferredInt) {
         try {
             System.setProperty("java.rmi.server.hostname", this.myIP);
             Registry registry = LocateRegistry.getRegistry(host, port);
@@ -61,16 +62,17 @@ public class RMIClient  implements IClient {
             this.username = username;
 
             ClientCallbackImpl callback = new ClientCallbackImpl(controller);
-            boolean joined = stub.joinGame(username, preferredInt, callback);
+            ErrorType status = stub.joinGame(username, preferredInt, callback);
-            if (!joined) return false;
+            if(status==null)
-
+            {
                 running = true;
                 startHeartbeat();
-            return true;
+                return null;
-
+            }
+            return status;
         } catch (Exception e) {
             e.printStackTrace();
-            return false;
+            return ErrorType.GENERIC_ERROR;
         }
     }
 
@@ -124,7 +126,7 @@ public class RMIClient  implements IClient {
         if (!running) return;
         running = false;
         if (pingSender != null) pingSender.shutdownNow();
-        controller.view.showError("Connection with server closed");
+        controller.view.showError(ErrorType.SERVER_CRASHED);
     }
 
 

src/main/java/it/polimi/ingsw/gc14/Network/RMI/Common/IGameServer.java

@@ -1,5 +1,7 @@
 package it.polimi.ingsw.gc14.Network.RMI.Common;
 
+import it.polimi.ingsw.gc14.ErrorType;
+
 import java.rmi.*;
 
 /**
@@ -18,7 +20,7 @@ public interface IGameServer extends Remote {
      *         {@code false} otherwise.
      * @throws RemoteException if an RMI communication error occurs.
      */
-    boolean joinGame(String username, int preferredInt, IClientCallback callback) throws RemoteException;
+    ErrorType joinGame(String username, int preferredInt, IClientCallback callback) throws RemoteException;
 
     /**
      * Requests to draw a tribe card from the upper tribe card list.

src/main/java/it/polimi/ingsw/gc14/Network/RMI/Server/RMIServer.java

@@ -1,8 +1,10 @@
 package it.polimi.ingsw.gc14.Network.RMI.Server;
 
 import it.polimi.ingsw.gc14.Controller.GameController;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.LimitedMap;
 import it.polimi.ingsw.gc14.Model.Game;
+import it.polimi.ingsw.gc14.Model.GamePackage.GameStages;
 import it.polimi.ingsw.gc14.Model.MiniModel;
 import it.polimi.ingsw.gc14.Network.NetworkEvent;
 import it.polimi.ingsw.gc14.Network.NetworkEvents.*;
@@ -81,9 +83,9 @@ public class RMIServer extends UnicastRemoteObject implements IGameServer {
      * {@code TCPServer.acceptHeartbeat()}.
      */
     @Override
-    public boolean joinGame(String username, int preferredInt, IClientCallback callback)
+    public ErrorType joinGame(String username, int preferredInt, IClientCallback callback)
             throws RemoteException {
-        if (preferredInt < 2 || preferredInt > 5) return false;
+        if (preferredInt < 2 || preferredInt > 5) return ErrorType.WRONG_PLAYER_NUMBER;
 
         synchronized (controller) {
 
@@ -92,32 +94,47 @@ public class RMIServer extends UnicastRemoteObject implements IGameServer {
                 playerList.setLimit(preferredInt);
                 System.out.println("Game Created With :"+preferredInt+" Players");
             }
+            if(controller.getModel().getCurrentState().getGameStage()!= GameStages.WAITING ) {
+                if (!controller.getModel().getPlayers().stream().anyMatch(p -> p.getUserName().equals(username))) {
+                    return ErrorType.GAME_ALREADY_STARTED;
+                }
+            }
+            else {
                 if (controller.addPlayer(username)) {
                     clients.put(username, callback);
                     playerList.put(username, true);
                     startWatchdog(username);
                     System.out.println("Accepted player: " + username);
-                return true;
+                    return null;
+                } else {
+                    return ErrorType.USERNAME_ALREADY_USED;
                 }
-            if(controller.getModel().getPlayers().stream().anyMatch(p -> p.getUserName().equals(username))&& !playerList.containsKey(username)) {
+            }
+
+
+            if(!playerList.containsKey(username)){
                 clients.put(username, callback);
                 playerList.put(username, true);
                 startWatchdog(username);
                 System.out.println("(After crash)Reconnected player: " + username);
-                return true;
+                return null;
             }
-            if (playerList.containsKey(username) && !playerList.get(username)) {
+            else {
+                if(!playerList.get(username))
+                {
                     playerList.put(username, true);
                     clients.put(username, callback);
                     System.out.println("Reconnected player: " + username);
                     startWatchdog(username);
                     Game game = controller.getModel();
-                callback.onGameInit(new MiniModel(game.getSlotMap(), game.orderLogicCard,game.getCurrentState(),game.getPlayers(),game.getAvailableTotems(),game.getUpperListTribeCards(),game.getLowerListTribeCards(),game.getUpperListBuilding(),game.getLowerListBuilding()));
+                    callback.onGameInit(new MiniModel(game.getSlotMap(), game.orderLogicCard, game.getCurrentState(), game.getPlayers(), game.getAvailableTotems(), game.getUpperListTribeCards(), game.getLowerListTribeCards(), game.getUpperListBuilding(), game.getLowerListBuilding()));
                     System.out.println("Model sent: " + username);
                     actionQueue.add(new ReconnectPlayer(username));
-                return true;
+                    return null;
+                }
+                else
+                    return ErrorType.USER_ALREADY_CONNECTED;
             }
-            return false;
         }
     }
 

src/main/java/it/polimi/ingsw/gc14/Network/TCP/Client/TCPClient.java

@@ -1,6 +1,7 @@
 package it.polimi.ingsw.gc14.Network.TCP.Client;
 
 import it.polimi.ingsw.gc14.Controller.ClientController;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Model.Game;
 import it.polimi.ingsw.gc14.Model.MiniModel;
 import it.polimi.ingsw.gc14.Network.IClient;
@@ -70,7 +71,7 @@ public class TCPClient implements IClient {
      * @param proposedNPlayers The desired number of players for the game
      * @return true if the connection is successful, false otherwise.
      */
-    public boolean connect(String user, int proposedNPlayers) {
+    public ErrorType connect(String user, int proposedNPlayers) {
         try {
             communicationSocket = new Socket(hostname, mainPort);
             socketSend    = new ObjectOutputStream(communicationSocket.getOutputStream());
@@ -80,7 +81,16 @@ public class TCPClient implements IClient {
            int read= communicationSocket.getInputStream().read();
             if ( read== -1) {
                 System.out.println("Could not connect to server");
-                return false;
+
+                try {
+                    if( socketReceive.readObject() instanceof AddPlayer x)
+                    {
+                        return x.getErrorType();
+                    }
+                } catch (ClassNotFoundException e) {
+                    return ErrorType.GENERIC_ERROR;
+                }
+                return ErrorType.GENERIC_ERROR;
             }
             new Thread(this::receiveMessage, "tcp-reader").start();
 
@@ -95,11 +105,11 @@ public class TCPClient implements IClient {
             new Thread(this::heartbeatLoop, "heartbeat").start();
 
             running = true;
-            return true;
+            return null;
 
         } catch (IOException e) {
             e.printStackTrace();
-            return false;
+            return ErrorType.GENERIC_ERROR;
         }
     }
 
@@ -143,7 +153,7 @@ public class TCPClient implements IClient {
         running = false;
         try { communicationSocket.close(); } catch (IOException ignored) {}
         try { heartbeatSocket.close();     } catch (IOException ignored) {}
-        controller.view.showError("Connection with server lost");
+        controller.view.showError(ErrorType.SERVER_CRASHED);
     }
 
 
@@ -166,7 +176,7 @@ public class TCPClient implements IClient {
 
                 if (read instanceof NetworkEvent event) {
                     if (event.getIsError()) {
-                        controller.view.showError(event.toString());
+                        controller.view.showError(event.getErrorType());
                     } else {
                         event.apply(controller.miniModel);
                         controller.view.render();

src/main/java/it/polimi/ingsw/gc14/Network/TCP/Server/TCPServer.java

@@ -1,8 +1,10 @@
 package it.polimi.ingsw.gc14.Network.TCP.Server;
 
 import it.polimi.ingsw.gc14.Controller.GameController;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.LimitedMap;
 import it.polimi.ingsw.gc14.Model.Game;
+import it.polimi.ingsw.gc14.Model.GamePackage.GameStages;
 import it.polimi.ingsw.gc14.Model.MiniModel;
 import it.polimi.ingsw.gc14.Network.EventType;
 import it.polimi.ingsw.gc14.Network.NetworkEvent;
@@ -168,7 +170,16 @@ public class TCPServer {
                         playerList.setLimit(eventAddPlayer.getProposedNPlayer());
                         System.out.println("Game Created With :"+eventAddPlayer.getProposedNPlayer()+" Players");
                     }
-
+                    if(controller.getModel().getCurrentState().getGameStage()!= GameStages.WAITING ) {
+                        if (!controller.getModel().getPlayers().stream().anyMatch(p -> p.getUserName().equals(username))) {
+                            clientSocket.getOutputStream().write(-1);
+                            eventAddPlayer.setErrorType(ErrorType.GAME_ALREADY_STARTED);
+                            clientSend.writeObject(eventAddPlayer);
+                            clientSocket.close();
+                            System.out.println("Invalid parameters. Connection terminated.");
+                        }
+                    }
+                    else{
                         if (controller.addPlayer(username)) {
                             playerList.put(username, true);
                             System.out.println("Accepted player: " + username);
@@ -194,9 +205,17 @@ public class TCPServer {
                             continue;
 
                         }
-                    if (controller.getModel().getPlayers().stream()
+                        else {
-                            .anyMatch(p -> p.getUserName().equals(username))
+                            clientSocket.getOutputStream().write(-1);
-                            && !playerList.containsKey(username)) {
+                            eventAddPlayer.setErrorType(ErrorType.USERNAME_ALREADY_USED);
+                            clientSend.writeObject(eventAddPlayer);
+                            clientSocket.close();
+                            System.out.println("Invalid parameters. Connection terminated.");
+                        }
+                    }
+
+
+                    if (!playerList.containsKey(username)) {
                         playerList.put(username, true);
                         System.out.println("(After crash)Reconnected player: " + username);
 
@@ -222,8 +241,8 @@ public class TCPServer {
 
                     }
                     //reconnect a previously disconnected player
-                    if (playerList.containsKey(username)
+                    else{
-                            && !playerList.get(username)) {
+                        if (!playerList.get(username)) {
 
                             playerList.put(username, true);
                             System.out.println("Reconnected player: " + username);
@@ -248,7 +267,7 @@ public class TCPServer {
                                     game.getCurrentState(),
                                     game.getPlayers(),
                                     game.getAvailableTotems(),
-                                game.getUpperListTribeCards(),game.getLowerListTribeCards(),game.getUpperListBuilding(),game.getLowerListBuilding()
+                                    game.getUpperListTribeCards(), game.getLowerListTribeCards(), game.getUpperListBuilding(), game.getLowerListBuilding()
                             ));
 
                             Thread thread = new Thread(handler);
@@ -260,8 +279,11 @@ public class TCPServer {
 
                         } else {
                             clientSocket.getOutputStream().write(-1);
+                            eventAddPlayer.setErrorType(ErrorType.USER_ALREADY_CONNECTED);
+                            clientSend.writeObject(eventAddPlayer);
                             clientSocket.close();
-                        System.out.println("Player could not be added. Connection terminated.");
+                            System.out.println("Invalid parameters. Connection terminated.");
+                        }
                     }
                 }
             } catch (IOException | ClassNotFoundException e) {

src/main/java/it/polimi/ingsw/gc14/View/GUI/GUI.java

@@ -1,25 +1,16 @@
 package it.polimi.ingsw.gc14.View.GUI;
 
 import it.polimi.ingsw.gc14.Controller.ClientController;
-import it.polimi.ingsw.gc14.Model.GamePackage.GameStages;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Model.MiniModel;
-import it.polimi.ingsw.gc14.Network.NetworkEvent;
-import it.polimi.ingsw.gc14.View.GUI.LoginFXMLController;
-import it.polimi.ingsw.gc14.View.GUI.MainFXMLController;
 import it.polimi.ingsw.gc14.View.IView;
-import javafx.animation.PauseTransition;
 import javafx.application.Application;
 import javafx.application.Platform;
-import javafx.beans.value.ChangeListener;
-import javafx.beans.value.ObservableValue;
 import javafx.fxml.FXMLLoader;
 import javafx.geometry.Rectangle2D;
 import javafx.scene.Scene;
 import javafx.stage.Screen;
 import javafx.stage.Stage;
-import javafx.util.Duration;
-
-import java.io.IOException;
 
 import static it.polimi.ingsw.gc14.Model.GamePackage.GameStages.ENDED;
 import static it.polimi.ingsw.gc14.Model.GamePackage.GameStages.TOTEM_CHOICE;
@@ -144,12 +135,11 @@ public class GUI extends Application implements IView {
     }
 
     @Override
-    public void showError(String message) {
+    public void showError(ErrorType error) {
         Platform.runLater(() -> {
             synchronized (miniModel) {
                 controllerMain.isError = true;
                 controllerMain.render();
-                System.out.println("ERRORE PORCODIDODODODOD");
             }
         });
     }

src/main/java/it/polimi/ingsw/gc14/View/GUI/LoginFXMLController.java

@@ -1,6 +1,7 @@
 package it.polimi.ingsw.gc14.View.GUI;
 
 import it.polimi.ingsw.gc14.Controller.ClientController;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Network.RMI.Client.RMIClient;
 import it.polimi.ingsw.gc14.Network.TCP.Client.TCPClient;
 import javafx.animation.*;
@@ -153,23 +154,28 @@ public class LoginFXMLController {
     private void connect(String nome, String ip, int numPlayers, String localInterface) {
         if (isRMI) {
             RMIClient client = new RMIClient(controller, ip, 1099, localInterface);
-            if (client.connect(nome, numPlayers)) {
+            ErrorType serverResponse=client.connect(nome, numPlayers);
+            if (serverResponse==null) {
                 controller.setClient(client);
                 Platform.runLater(() -> showSuccess("Connected! Waiting for other players…"));
             } else {
-                Platform.runLater(() -> showError("RMI connection failed."));
+                Platform.runLater(() -> showError(serverResponse));
             }
         } else {
             TCPClient client = new TCPClient(controller, ip, 8080, 8081);
-            if (client.connect(nome, numPlayers)) {
+            ErrorType serverResponse=client.connect(nome, numPlayers);
+            if (serverResponse==null) {
                 controller.setClient(client);
                 Platform.runLater(() -> showSuccess("Connected! Waiting for other players…"));
             } else {
-                Platform.runLater(() -> showError("TCP connection failed."));
+                Platform.runLater(() -> showError(serverResponse));
             }
         }
     }
-
+    private void showError(ErrorType errorType) {
+        labelErrore.setTextFill(Color.web("#e05050"));
+        labelErrore.setText(errorType.toString());
+    }
     private void showError(String msg) {
         labelErrore.setTextFill(Color.web("#e05050"));
         labelErrore.setText(msg);

src/main/java/it/polimi/ingsw/gc14/View/IView.java

@@ -1,5 +1,6 @@
 package it.polimi.ingsw.gc14.View;
 
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Model.Game;
 import it.polimi.ingsw.gc14.Model.MiniModel;
 import it.polimi.ingsw.gc14.Network.NetworkEvent;
@@ -7,7 +8,9 @@ import it.polimi.ingsw.gc14.Network.NetworkEvent;
 public interface IView {
     public void setModel(MiniModel miniModel);
     public void render();
-    public void showMessage(String message);
+
-    public void showError(String message);
+    void showMessage(String message);
+
+    public void showError(ErrorType error);
 
 }

src/main/java/it/polimi/ingsw/gc14/View/TUI/TUI.java

@@ -1,4 +1,5 @@
 package it.polimi.ingsw.gc14.View.TUI;
+import it.polimi.ingsw.gc14.ErrorType;
 import it.polimi.ingsw.gc14.Model.*;
 import it.polimi.ingsw.gc14.Model.GamePackage.GameStages;
 import it.polimi.ingsw.gc14.Network.NetworkEvent;
@@ -231,12 +232,12 @@ public class TUI implements IView {
     /**
      * Prints an error message to standard output.
      *
-     * @param message the error message to display
+     * @param error the error message to display
      */
-    public void showError(String message) {
+    public void showError(ErrorType error) {
         clearTerminal();
         render();
-        System.out.println(message);
+        System.out.println(error);
     }
 
     /**