LiveConfigSystem.h

// Copyright (c) 2026 Nicholas Arthur
// Licensed under the MIT License
 
#pragma once
 
#include "UObject/UnrealType.h"
#include "Subsystems/EngineSubsystem.h"
#include "Interfaces/IHttpRequest.h"
#include "CoreMinimal.h"
#include "LiveConfigTypes.h"
#include "LiveConfigPropertyName.h"
#include "Profiles/LiveConfigProfile.h"
#include "ConsoleSettings.h"
#include "LiveConfigSystem.generated.h"
 
DECLARE_MULTICAST_DELEGATE(FOnLiveConfigPropertiesUpdated);
DECLARE_MULTICAST_DELEGATE_OneParam(FOnRemoteSyncDetected, const TArray<FLiveConfigPropertyDefinition>&);
 
namespace LiveConfigTags
{
    const LIVECONFIG_API extern FName FromCurveTable;
}
 
UCLASS(BlueprintType, Config=Game, DefaultConfig)
class LIVECONFIG_API ULiveConfigSystem : public UEngineSubsystem
{
    GENERATED_BODY()
 
public:
    FOnLiveConfigPropertiesUpdated OnPropertiesUpdated;
 
    FSimpleMulticastDelegate OnTagsChanged;
 
    FSimpleMulticastDelegate OnRemoteOverridesLoaded;
    
    FOnRemoteSyncDetected OnDataProviderSync;
    
    static ULiveConfigSystem& Get();
 
    // USubsystem
    virtual void Initialize(FSubsystemCollectionBase& Collection) override;
    virtual void Deinitialize() override;
    virtual bool ShouldCreateSubsystem(UObject* Outer) const override;
    // ~USubsystem
 
    void SaveProperty(const FLiveConfigPropertyDefinition& PropertyDefinition);
 
    bool UpdateStructProperties(const FLiveConfigPropertyDefinition& PropertyDefinition);
    
    void SavePropertyDeferred(const FLiveConfigPropertyDefinition& PropertyDefinition);
 
    void RenameProperty(FLiveConfigProperty OldName, FLiveConfigProperty NewName, bool bCreateRedirector = false);
    
    void DeleteProperty(FLiveConfigProperty Property);
 
    FString GetStringValue(FLiveConfigProperty Key) const;
 
    float GetFloatValue(FLiveConfigProperty Key) const;
 
    int32 GetIntValue(FLiveConfigProperty Key) const;
 
    bool GetBoolValue(FLiveConfigProperty Key) const;
 
    template<typename T>
    T GetLiveConfigStruct(FLiveConfigProperty StructProperty) const
    {
        T OutStruct;
        UScriptStruct* Struct = TBaseStructure<T>::Get();
        if (!Struct)
        {
            Struct = T::StaticStruct();
        }
        GetLiveConfigStruct_Internal(Struct, &OutStruct, StructProperty);
        return OutStruct;
    }
 
    template<typename T>
    T GetLiveConfigValue(FLiveConfigProperty Property) const
    {
        RedirectPropertyName(Property);
        return Cache.GetValue<T>(Property);
    }
    
    void GetLiveConfigStruct_Internal(class UScriptStruct* Struct, void* OutStructPtr, FLiveConfigProperty Prefix) const;
    
    void GetStructPropertyMembers(FLiveConfigProperty StructProperty, TArray<FLiveConfigProperty>& OutProperties);
 
    void GetSubProperties(FName PropertyPath, TArray<FLiveConfigProperty>& OutProperties);
 
    UFUNCTION(BlueprintCallable, Category = "Live Config")
    bool IsDataReady() const { return bIsDataReady; }
 
    UFUNCTION(BlueprintCallable, Category = "Live Config")
    void PatchEnvironmentOverrides(const FLiveConfigProfile& InProfile);
    
    void SyncRemoteToLocal();
    
    TArray<FLiveConfigPropertyDefinition> GetProfileDiff(const FLiveConfigProfile& Profile);
    
    const TArray<FLiveConfigPropertyDefinition>& SaveProperties(const TArray<FLiveConfigPropertyDefinition>& Properties);
    FString GetDiffString(const TArray<FLiveConfigPropertyDefinition>& Diff);
    
    FText GetDiffText(const TArray<FLiveConfigPropertyDefinition>& Diff);
    
 
    void DownloadConfig();
 
    void RebuildConfigCache();
    void RebuildConfigCache(const FLiveConfigProfile& Profile);
 
    UFUNCTION(BlueprintCallable, Category = "Live Config")
    const TMap<FLiveConfigProperty, FLiveConfigPropertyDefinition>& GetAllProperties() const;
 
    static bool DoesPropertyNameExist(FLiveConfigProperty PropertyName);
 
    void RedirectPropertyName(FLiveConfigProperty& Property) const;
 
    static void GetActiveSource(ELiveConfigSourceType& OutSourceType, FString& OutSourcePath);
 
    void RemoveRedirect(FName OldPropertyName);
 
    UPROPERTY(VisibleAnywhere, BlueprintReadOnly, Category = "General")
    TMap<FLiveConfigProperty, FLiveConfigPropertyDefinition> PropertyDefinitions;
    
    UPROPERTY(Config, VisibleAnywhere, BlueprintReadOnly, Category = "General")
    TArray<FName> PropertyTags;
    
    void HandleTagsChanged();
    
 
    UPROPERTY(Config)
    TMap<FName, FName> PropertyRedirects;
 
 
private:
    double TimeLoadStarted = -9999;
    float RateLimitSeconds = 5;
    FTimerHandle PollingTimer;
    FTSTicker::FDelegateHandle TimeoutTimer;
    
    UPROPERTY()
    FLiveConfigCache Cache;
    
    // Environment config is treated as a layer below more specific profiles
    FLiveConfigProfile EnvironmentOverrides;
    
    float TimeoutDuration;
 
    void OnTravel(UWorld* World, FWorldInitializationValues WorldInitializationValues);
    void OnStartGameInstance(UGameInstance* GameInstance);
 
    UFUNCTION()
    void BuildCache();
 
    void PopulateAutoCompleteEntries(TArray<FAutoCompleteCommand>& AutoCompleteCommands);
 
    void FetchOverrides(ELiveConfigSourceType SourceType, const FString& SourcePath, const FOnRemoteOverridesFetched& OnComplete);
 
    void FetchProfileCommand(const TArray<FString>& Args);
 
    bool bIsDataReady = false;
};