Improve NetPlay connection error handling

Source/Core/Core/NetPlayClient.cpp

@@ -93,7 +93,8 @@ NetPlayClient::NetPlayClient(const std::string& address, const u16 port, NetPlay
 
     if (m_client == nullptr)
     {
-      PanicAlertT("Couldn't Create Client");
+      m_dialog->OnConnectionError(_trans("Could not create client."));
+      return;
     }
 
     ENetAddress addr;
@@ -104,7 +105,8 @@ NetPlayClient::NetPlayClient(const std::string& address, const u16 port, NetPlay
 
     if (m_server == nullptr)
     {
-      PanicAlertT("Couldn't create peer.");
+      m_dialog->OnConnectionError(_trans("Could not create peer."));
+      return;
     }
 
     ENetEvent netEvent;
@@ -119,14 +121,15 @@ NetPlayClient::NetPlayClient(const std::string& address, const u16 port, NetPlay
     }
     else
     {
-      PanicAlertT("Failed to Connect!");
+      m_dialog->OnConnectionError(_trans("Could not communicate with host."));
     }
   }
   else
   {
     if (address.size() > NETPLAY_CODE_SIZE)
     {
-      PanicAlertT("Host code size is to large.\nPlease recheck that you have the correct code");
+      m_dialog->OnConnectionError(
+          _trans("Host code size is too large.\nPlease recheck that you have the correct code."));
       return;
     }
 
@@ -174,7 +177,7 @@ NetPlayClient::NetPlayClient(const std::string& address, const u16 port, NetPlay
       if (connect_timer.GetTimeElapsed() > 5000)
         break;
     }
-    PanicAlertT("Failed To Connect!");
+    m_dialog->OnConnectionError(_trans("Could not communicate with host."));
   }
 }
 
@@ -209,16 +212,17 @@ bool NetPlayClient::Connect()
     switch (error)
     {
     case CON_ERR_SERVER_FULL:
-      PanicAlertT("The server is full!");
+      m_dialog->OnConnectionError(_trans("The server is full."));
       break;
     case CON_ERR_VERSION_MISMATCH:
-      PanicAlertT("The server and client's NetPlay versions are incompatible!");
+      m_dialog->OnConnectionError(
+          _trans("The server and client's NetPlay versions are incompatible."));
       break;
     case CON_ERR_GAME_RUNNING:
-      PanicAlertT("The server responded: the game is currently running!");
+      m_dialog->OnConnectionError(_trans("The game is currently running."));
       break;
     default:
-      PanicAlertT("The server sent an unknown error message!");
+      m_dialog->OnConnectionError(_trans("The server sent an unknown error message."));
       break;
     }
 

Source/Core/Core/NetPlayClient.h

@@ -34,6 +34,7 @@ public:
   virtual void OnPadBufferChanged(u32 buffer) = 0;
   virtual void OnDesync(u32 frame, const std::string& player) = 0;
   virtual void OnConnectionLost() = 0;
+  virtual void OnConnectionError(const std::string& message) = 0;
   virtual void OnTraversalError(TraversalClient::FailureReason error) = 0;
   virtual bool IsRecording() = 0;
   virtual std::string FindGame(const std::string& game) = 0;

Source/Core/Core/NetPlayServer.cpp

@@ -173,7 +173,7 @@ void NetPlayServer::ThreadFunc()
             delete (PlayerId*)netEvent.peer->data;
             netEvent.peer->data = nullptr;
           }
-          enet_peer_disconnect(accept_peer, 0);
+          enet_peer_disconnect_later(accept_peer, 0);
         }
       }
       break;

Source/Core/DolphinQt2/MainWindow.cpp

@@ -1085,8 +1085,6 @@ bool MainWindow::NetPlayJoin()
 
   if (!Settings::Instance().GetNetPlayClient()->IsConnected())
   {
-    QMessageBox::critical(nullptr, QObject::tr("Error"),
-                          QObject::tr("Failed to connect to server"));
     NetPlayQuit();
     return false;
   }

Source/Core/DolphinQt2/NetPlay/NetPlayDialog.cpp

@@ -558,6 +558,14 @@ void NetPlayDialog::OnConnectionLost()
   DisplayMessage(tr("Lost connection to NetPlay server..."), "red");
 }
 
+void NetPlayDialog::OnConnectionError(const std::string& message)
+{
+  QueueOnObject(this, [this, message] {
+    QMessageBox::critical(this, tr("Error"),
+                          tr("Failed to connect to server: %1").arg(tr(message.c_str())));
+  });
+}
+
 void NetPlayDialog::OnTraversalError(TraversalClient::FailureReason error)
 {
   QueueOnObject(this, [this, error] {

Source/Core/DolphinQt2/NetPlay/NetPlayDialog.h

@@ -49,6 +49,7 @@ public:
   void OnPadBufferChanged(u32 buffer) override;
   void OnDesync(u32 frame, const std::string& player) override;
   void OnConnectionLost() override;
+  void OnConnectionError(const std::string& message) override;
   void OnTraversalError(TraversalClient::FailureReason error) override;
   bool IsRecording() override;
   std::string FindGame(const std::string& game) override;