TraversalClient: Convert state enum into an enum class

Prevents implicit conversions and prevents identifiers from polluting
the class scope.

Source/Core/Common/TraversalClient.cpp

@@ -48,7 +48,7 @@ void TraversalClient::ReconnectToServer()
   }
   m_ServerAddress.port = m_port;
 
-  m_State = Connecting;
+  m_State = State::Connecting;
 
   TraversalPacket hello = {};
   hello.type = TraversalPacketHelloFromClient;
@@ -145,7 +145,7 @@ void TraversalClient::HandleServerPacket(TraversalPacket* packet)
     }
     break;
   case TraversalPacketHelloFromServer:
-    if (m_State != Connecting)
+    if (!IsConnecting())
       break;
     if (!packet->helloFromServer.ok)
     {
@@ -153,7 +153,7 @@ void TraversalClient::HandleServerPacket(TraversalPacket* packet)
       break;
     }
     m_HostId = packet->helloFromServer.yourHostId;
-    m_State = Connected;
+    m_State = State::Connected;
     if (m_Client)
       m_Client->OnTraversalStateChanged();
     break;
@@ -214,7 +214,7 @@ void TraversalClient::HandleServerPacket(TraversalPacket* packet)
 
 void TraversalClient::OnFailure(FailureReason reason)
 {
-  m_State = Failure;
+  m_State = State::Failure;
   m_FailureReason = reason;
 
   if (m_Client)
@@ -257,7 +257,7 @@ void TraversalClient::HandleResends()
 void TraversalClient::HandlePing()
 {
   const u32 now = enet_time_get();
-  if (m_State == Connected && now - m_PingTime >= 500)
+  if (IsConnected() && now - m_PingTime >= 500)
   {
     TraversalPacket ping = {};
     ping.type = TraversalPacketPing;

Source/Core/Common/TraversalClient.h

@@ -25,11 +25,11 @@ public:
 class TraversalClient
 {
 public:
-  enum State
+  enum class State
   {
     Connecting,
     Connected,
-    Failure
+    Failure,
   };
   enum class FailureReason
   {
@@ -46,6 +46,10 @@ public:
   State GetState() const;
   FailureReason GetFailureReason() const;
 
+  bool HasFailed() const { return m_State == State::Failure; }
+  bool IsConnecting() const { return m_State == State::Connecting; }
+  bool IsConnected() const { return m_State == State::Connected; }
+
   void Reset();
   void ConnectToClient(const std::string& host);
   void ReconnectToServer();

Source/Core/Core/NetPlayClient.cpp

@@ -174,7 +174,7 @@ NetPlayClient::NetPlayClient(const std::string& address, const u16 port, NetPlay
     m_traversal_client = g_TraversalClient.get();
 
     // If we were disconnected in the background, reconnect.
-    if (m_traversal_client->GetState() == TraversalClient::Failure)
+    if (m_traversal_client->HasFailed())
       m_traversal_client->ReconnectToServer();
     m_traversal_client->m_Client = this;
     m_host_spec = address;
@@ -1755,12 +1755,13 @@ void NetPlayClient::OnTraversalStateChanged()
   const TraversalClient::State state = m_traversal_client->GetState();
 
   if (m_connection_state == ConnectionState::WaitingForTraversalClientConnection &&
-      state == TraversalClient::Connected)
+      state == TraversalClient::State::Connected)
   {
     m_connection_state = ConnectionState::WaitingForTraversalClientConnectReady;
     m_traversal_client->ConnectToClient(m_host_spec);
   }
-  else if (m_connection_state != ConnectionState::Failure && state == TraversalClient::Failure)
+  else if (m_connection_state != ConnectionState::Failure &&
+           state == TraversalClient::State::Failure)
   {
     Disconnect();
     m_dialog->OnTraversalError(m_traversal_client->GetFailureReason());

Source/Core/Core/NetPlayServer.cpp

@@ -126,7 +126,7 @@ NetPlayServer::NetPlayServer(const u16 port, const bool forward_port, NetPlayUI*
 
     m_server = g_MainNetHost.get();
 
-    if (g_TraversalClient->GetState() == TraversalClient::Failure)
+    if (g_TraversalClient->HasFailed())
       g_TraversalClient->ReconnectToServer();
   }
   else
@@ -190,7 +190,7 @@ void NetPlayServer::SetupIndex()
 
   if (m_traversal_client)
   {
-    if (m_traversal_client->GetState() != TraversalClient::Connected)
+    if (!m_traversal_client->IsConnected())
       return;
 
     session.server_id = std::string(g_TraversalClient->GetHostID().data(), 8);
@@ -1149,7 +1149,7 @@ void NetPlayServer::OnTraversalStateChanged()
   if (!m_dialog)
     return;
 
-  if (state == TraversalClient::Failure)
+  if (state == TraversalClient::State::Failure)
     m_dialog->OnTraversalError(m_traversal_client->GetFailureReason());
 
   m_dialog->OnTraversalStateChanged(state);

Source/Core/DolphinQt/NetPlay/NetPlayDialog.cpp

@@ -711,11 +711,11 @@ void NetPlayDialog::UpdateGUI()
   {
     switch (g_TraversalClient->GetState())
     {
-    case TraversalClient::Connecting:
+    case TraversalClient::State::Connecting:
       m_hostcode_label->setText(tr("..."));
       m_hostcode_action_button->setEnabled(false);
       break;
-    case TraversalClient::Connected:
+    case TraversalClient::State::Connected:
     {
       const auto host_id = g_TraversalClient->GetHostID();
       m_hostcode_label->setText(
@@ -725,7 +725,7 @@ void NetPlayDialog::UpdateGUI()
       m_is_copy_button_retry = false;
       break;
     }
-    case TraversalClient::Failure:
+    case TraversalClient::State::Failure:
       m_hostcode_label->setText(tr("Error"));
       m_hostcode_action_button->setText(tr("Retry"));
       m_hostcode_action_button->setEnabled(true);
@@ -1003,6 +1003,7 @@ void NetPlayDialog::OnTraversalStateChanged(TraversalClient::State state)
   case TraversalClient::State::Connected:
   case TraversalClient::State::Failure:
     UpdateDiscordPresence();
+    break;
   default:
     break;
   }