feat: server decides game difficulty

Code/client/Games/Skyrim/PlayerCharacter.cpp

@@ -29,9 +29,20 @@ static TCalculateExperience* RealCalculateExperience = nullptr;
 
 void PlayerCharacter::SetDifficulty(const int32_t aDifficulty) noexcept
 {
+    if (aDifficulty > 5)
+        return;
+
+    // TODO(cosideci): cache pre-connect difficulty
+
+    // Can't find "iDifficulty:GamePlay"
+    /*
     auto* pSettings = INISettingCollection::Get();
     Setting* pSetting = pSettings->GetSetting("iDifficulty:GamePlay");
     pSetting->data = aDifficulty;
+    */
+
+    POINTER_SKYRIMSE(int32_t, s_difficulty, 381472);
+    *s_difficulty = aDifficulty;
 
     difficulty = aDifficulty;
 }

Code/client/Services/Generic/PlayerService.cpp

@@ -12,6 +12,8 @@
 #include <Messages/EnterExteriorCellRequest.h>
 #include <Messages/EnterInteriorCellRequest.h>
 
+#include <Structs/ServerSettings.h>
+
 #include <PlayerCharacter.h>
 #include <Forms/TESObjectCELL.h>
 #include <Games/Overrides.h>
@@ -20,6 +22,7 @@ PlayerService::PlayerService(World& aWorld, entt::dispatcher& aDispatcher, Trans
     : m_world(aWorld), m_dispatcher(aDispatcher), m_transport(aTransport)
 {
     m_updateConnection = m_dispatcher.sink<UpdateEvent>().connect<&PlayerService::OnUpdate>(this);
+    m_settingsConnection = m_dispatcher.sink<ServerSettings>().connect<&PlayerService::OnServerSettingsReceived>(this);
     m_notifyRespawnConnection = m_dispatcher.sink<NotifyPlayerRespawn>().connect<&PlayerService::OnNotifyPlayerRespawn>(this);
     m_gridCellChangeConnection = m_dispatcher.sink<GridCellChangeEvent>().connect<&PlayerService::OnGridCellChangeEvent>(this);
     m_cellChangeConnection = m_dispatcher.sink<CellChangeEvent>().connect<&PlayerService::OnCellChangeEvent>(this);
@@ -30,6 +33,12 @@ void PlayerService::OnUpdate(const UpdateEvent& acEvent) noexcept
     RunRespawnUpdates(acEvent.Delta);
 }
 
+void PlayerService::OnServerSettingsReceived(const ServerSettings& acSettings) const noexcept
+{
+    if (acSettings.Difficulty <= 5)
+        PlayerCharacter::Get()->SetDifficulty(acSettings.Difficulty);
+}
+
 void PlayerService::OnNotifyPlayerRespawn(const NotifyPlayerRespawn& acMessage) const noexcept
 {
     PlayerCharacter::Get()->PayGold(acMessage.GoldLost);

Code/client/Services/Generic/TransportService.cpp

@@ -154,6 +154,7 @@ void TransportService::HandleAuthenticationResponse(const AuthenticationResponse
     {
         m_connected = true;
         m_dispatcher.trigger(acMessage.UserMods);
+        m_dispatcher.trigger(acMessage.Settings);
         m_dispatcher.trigger(ConnectedEvent());
         break;
     }

Code/client/Services/PlayerService.h

@@ -4,6 +4,7 @@ struct World;
 struct TransportService;
 
 struct UpdateEvent;
+struct ServerSettings;
 struct GridCellChangeEvent;
 struct CellChangeEvent;
 
@@ -22,6 +23,7 @@ struct PlayerService
 protected:
 
     void OnUpdate(const UpdateEvent& acEvent) noexcept;
+    void OnServerSettingsReceived(const ServerSettings& acSettings) const noexcept;
     void OnNotifyPlayerRespawn(const NotifyPlayerRespawn& acMessage) const noexcept;
     void OnGridCellChangeEvent(const GridCellChangeEvent& acEvent) const noexcept;
     void OnCellChangeEvent(const CellChangeEvent& acEvent) const noexcept;
@@ -40,6 +42,7 @@ struct PlayerService
     double m_respawnTimer = 0.0;
 
     entt::scoped_connection m_updateConnection;
+    entt::scoped_connection m_settingsConnection;
     entt::scoped_connection m_notifyRespawnConnection;
     entt::scoped_connection m_gridCellChangeConnection;
     entt::scoped_connection m_cellChangeConnection;

Code/encoding/Messages/AuthenticationResponse.cpp

@@ -5,11 +5,13 @@ void AuthenticationResponse::SerializeRaw(TiltedPhoques::Buffer::Writer& aWriter
     Serialization::WriteVarInt(aWriter, static_cast<uint32_t>(Type));
     Serialization::WriteString(aWriter, Version);
     UserMods.Serialize(aWriter);
+    Settings.Serialize(aWriter);
 }
 
 void AuthenticationResponse::DeserializeRaw(TiltedPhoques::Buffer::Reader& aReader) noexcept
 {
     Type = static_cast<ResponseType>(Serialization::ReadVarInt(aReader) & 0xFFFFFFFF);
     Version = Serialization::ReadString(aReader);
     UserMods.Deserialize(aReader);
+    Settings.Deserialize(aReader);
 }

Code/encoding/Messages/AuthenticationResponse.h

@@ -2,6 +2,7 @@
 
 #include "Message.h"
 #include <Structs/Mods.h>
+#include <Structs/ServerSettings.h>
 
 struct AuthenticationResponse final : ServerMessage
 {
@@ -23,10 +24,14 @@ struct AuthenticationResponse final : ServerMessage
 
     bool operator==(const AuthenticationResponse& achRhs) const noexcept
     {
-        return GetOpcode() == achRhs.GetOpcode() && Type == achRhs.Type && UserMods == achRhs.UserMods;
+        return GetOpcode() == achRhs.GetOpcode() && 
+               Type == achRhs.Type && 
+               UserMods == achRhs.UserMods &&
+               Settings == achRhs.Settings;
     }
 
     ResponseType Type;
     String Version;
     Mods UserMods{};
+    ServerSettings Settings{};
 };

Code/encoding/Structs/ServerSettings.cpp

@@ -0,0 +1,25 @@
+#include "ServerSettings.h"
+#include <TiltedCore/Serialization.hpp>
+
+using TiltedPhoques::Serialization;
+
+bool ServerSettings::operator==(const ServerSettings& acRhs) const noexcept
+{
+    return Difficulty == acRhs.Difficulty;
+}
+
+bool ServerSettings::operator!=(const ServerSettings& acRhs) const noexcept
+{
+    return !this->operator==(acRhs);
+}
+
+void ServerSettings::Serialize(TiltedPhoques::Buffer::Writer& aWriter) const noexcept
+{
+    Serialization::WriteVarInt(aWriter, Difficulty);
+}
+
+void ServerSettings::Deserialize(TiltedPhoques::Buffer::Reader& aReader) noexcept
+{
+    Difficulty = Serialization::ReadVarInt(aReader) & 0xFFFFFFFF;
+}
+

Code/encoding/Structs/ServerSettings.h

@@ -0,0 +1,16 @@
+#pragma once
+
+#include <TiltedCore/Buffer.hpp>
+
+using TiltedPhoques::Buffer;
+
+struct ServerSettings
+{
+    bool operator==(const ServerSettings& acRhs) const noexcept;
+    bool operator!=(const ServerSettings& acRhs) const noexcept;
+
+    void Serialize(TiltedPhoques::Buffer::Writer& aWriter) const noexcept;
+    void Deserialize(TiltedPhoques::Buffer::Reader& aReader) noexcept;
+
+    uint32_t Difficulty;
+};

Code/server/GameServer.cpp

@@ -40,6 +40,8 @@ Console::StringSetting sAdminPassword{"GameServer:sAdminPassword", "Admin authen
 Console::StringSetting sToken{"GameServer:sToken", "Admin token", ""};
 Console::Setting bEnableMoPo{"ModPolicy:bEnabled", "Bypass the mod policy restrictions.", true,
                              Console::SettingsFlags::kHidden | Console::SettingsFlags::kLocked};
+// TODO: if difficulty is higher than 5, close server with error
+Console::Setting uDifficulty{"Gameplay:uDifficulty", "In game difficulty (0 to 5)", 4u};
 // -- Commands --
 Console::Command<bool> TogglePremium("TogglePremium", "Toggle the premium mode",
                                      [](Console::ArgStack& aStack) { bPremiumTickrate = aStack.Pop<bool>(); });
@@ -554,6 +556,8 @@ void GameServer::HandleAuthenticationRequest(const ConnectionId_t aConnectionId,
         spdlog::info("New player {:x} connected with {} mods\n\t: {}", aConnectionId,
                      acRequest->UserMods.ModList.size(), modList.c_str());
 
+        serverResponse.Settings.Difficulty = uDifficulty.value_as<uint8_t>();
+
         serverResponse.Type = AuthenticationResponse::ResponseType::kAccepted;
         Send(aConnectionId, serverResponse);