Back up save before overwrite

Source/AgrarianGame/AgrarianPersistenceSubsystem.cpp

@@ -10,6 +10,9 @@
 #include "AgrarianSurvivalComponent.h"
 #include "EngineUtils.h"
 #include "Engine/World.h"
+#include "HAL/FileManager.h"
+#include "Misc/DateTime.h"
+#include "Misc/Paths.h"
 #include "GameFramework/PlayerState.h"
 #include "Kismet/GameplayStatics.h"
 
@@ -33,6 +36,11 @@ UAgrarianSaveGame* UAgrarianPersistenceSubsystem::LoadOrCreateSave() const
 
 bool UAgrarianPersistenceSubsystem::WriteSave(UAgrarianSaveGame* SaveGame) const
 {
+	if (SaveGame && bBackupBeforeSave)
+	{
+		BackupExistingSave();
+	}
+
 	return SaveGame ? UGameplayStatics::SaveGameToSlot(SaveGame, DefaultSlotName, UserIndex) : false;
 }
 
@@ -316,6 +324,25 @@ bool UAgrarianPersistenceSubsystem::LoadCurrentWorld(int32& RestoredPlayerCount,
 	return bRestoredWorldState;
 }
 
+bool UAgrarianPersistenceSubsystem::BackupExistingSave() const
+{
+	const FString SaveFilePath = FPaths::Combine(FPaths::ProjectSavedDir(), TEXT("SaveGames"), DefaultSlotName + TEXT(".sav"));
+	if (!FPaths::FileExists(SaveFilePath))
+	{
+		return false;
+	}
+
+	const FString BackupDirectory = FPaths::Combine(FPaths::ProjectSavedDir(), TEXT("SaveGames"), TEXT("Backups"));
+	IFileManager::Get().MakeDirectory(*BackupDirectory, true);
+
+	const FString Timestamp = FDateTime::UtcNow().ToString(TEXT("%Y%m%dT%H%M%SZ"));
+	const FString BackupFileName = FString::Printf(TEXT("%s-%s.sav"), *DefaultSlotName, *Timestamp);
+	const FString BackupFilePath = FPaths::Combine(BackupDirectory, BackupFileName);
+	const bool bCopied = IFileManager::Get().Copy(*BackupFilePath, *SaveFilePath, true, true) == COPY_OK;
+	UE_LOG(LogTemp, Log, TEXT("Agrarian save backup %s: %s"), bCopied ? TEXT("created") : TEXT("failed"), *BackupFilePath);
+	return bCopied;
+}
+
 bool UAgrarianPersistenceSubsystem::CapturePlayerIntoSave(const AAgrarianGameCharacter* Character, UAgrarianSaveGame* SaveGame) const
 {
 	const UAgrarianSurvivalComponent* SurvivalComponent = Character ? Character->GetSurvivalComponent() : nullptr;

Source/AgrarianGame/AgrarianPersistenceSubsystem.h

@@ -23,6 +23,9 @@ public:
 	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Agrarian|Persistence")
 	int32 UserIndex = 0;
 
+	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Agrarian|Persistence")
+	bool bBackupBeforeSave = true;
+
 	UPROPERTY(EditAnywhere, BlueprintReadWrite, Category = "Agrarian|Persistence")
 	TMap<FName, TSubclassOf<AActor>> WorldActorClassRegistry;
 
@@ -78,6 +81,7 @@ public:
 	bool LoadCurrentWorld(int32& RestoredPlayerCount, int32& RestoredWorldActorCount, bool bClearExistingActors = true) const;
 
 protected:
+	bool BackupExistingSave() const;
 	bool CapturePlayerIntoSave(const AAgrarianGameCharacter* Character, UAgrarianSaveGame* SaveGame) const;
 	bool RestorePlayerFromSave(AAgrarianGameCharacter* Character, const UAgrarianSaveGame* SaveGame) const;
 	void FindPersistentComponents(TArray<UAgrarianPersistentActorComponent*>& OutComponents) const;