// Copyright Epic Games, Inc. All Rights Reserved.

#include "Commandlets/SavePackageUtilitiesCommandlet.h"

#include "Editor.h"
#include "HAL/IConsoleManager.h"
#include "HAL/FileManager.h"
#include "HAL/IConsoleManager.h"
#include "Interfaces/ITargetPlatformManagerModule.h"
#include "Misc/CoreMisc.h"
#include "Misc/FeedbackContext.h"
#include "Misc/PackageName.h"
#include "Misc/Paths.h"
#include "UObject/ArchiveCookContext.h"
#include "UObject/LinkerDiff.h"
#include "UObject/LinkerSave.h"
#include "UObject/Package.h"
#include "UObject/SavePackage.h"
#include "UObject/UObjectGlobals.h"
#include "UObject/UObjectHash.h"

USavePackageUtilitiesCommandlet::USavePackageUtilitiesCommandlet(const FObjectInitializer& ObjectInitializer)
	: Super(ObjectInitializer)
{
}

int32 USavePackageUtilitiesCommandlet::Main(const FString& Params)
{
	InitParameters(Params);

	for (const FString& PackageName : PackageNames)
	{
		// Load Package
		UPackage* Package = LoadPackage(nullptr, *PackageName, LOAD_None);
		UObject* Asset = Package->FindAssetInPackage();
		FString Filename = FPaths::CreateTempFilename(*FPaths::ProjectSavedDir());

		// CookData should only be nonzero if we are cooking.
		TOptional<FArchiveCookData> CookData;
		FArchiveCookContext CookContext(Package, FArchiveCookContext::ECookTypeUnknown);
		if (TargetPlatform != nullptr)
		{
			CookData.Emplace(*TargetPlatform, CookContext);
		}

		FSavePackageArgs SaveArgs;
		SaveArgs.TopLevelFlags = RF_Public;
		SaveArgs.SaveFlags = SAVE_CompareLinker;
		SaveArgs.ArchiveCookData = CookData.GetPtrOrNull();
		SaveArgs.bSlowTask = false;

		// if not cooking add RF_Standalone to the top level flags
		if (TargetPlatform == nullptr)
		{
			SaveArgs.TopLevelFlags |= RF_Standalone;
		}

		FSavePackageResultStruct FirstResult = GEditor->Save(Package, Asset, *Filename, SaveArgs);
		FSavePackageResultStruct SecondResult = GEditor->Save(Package, Asset, *Filename, SaveArgs);
	
		if (FirstResult.LinkerSave && SecondResult.LinkerSave)
		{
			// Compare Linker Save info
			FLinkerDiff LinkerDiff = FLinkerDiff::CompareLinkers(FirstResult.LinkerSave.Get(), SecondResult.LinkerSave.Get());
			LinkerDiff.PrintDiff(*GWarn);
		}

		// Delete the temp filename
		IFileManager::Get().Delete(*Filename);
	}

	return 0;
}

void USavePackageUtilitiesCommandlet::InitParameters(const FString& Params)
{
	TArray<FString> Tokens;
	TArray<FString> Switches;
	ParseCommandLine(*Params, Tokens, Switches);

	FString SwitchValue;
	for (const FString& CurrentSwitch : Switches)
	{
		if (FParse::Value(*CurrentSwitch, TEXT("PACKAGE="), SwitchValue))
		{
			FString LongPackageName;
			FPackageName::SearchForPackageOnDisk(SwitchValue, &LongPackageName, nullptr);
			PackageNames.Add(MoveTemp(LongPackageName));

		}
		else if (FParse::Value(*CurrentSwitch, TEXT("PACKAGEFOLDER="), SwitchValue))
		{
			FPackageName::IteratePackagesInDirectory(SwitchValue, [this](const TCHAR* Filename)
				{
					PackageNames.Add(FPackageName::FilenameToLongPackageName(Filename));
					return true;
				});
		}
		else if (FParse::Value(*CurrentSwitch, TEXT("CookPlatform="), SwitchValue))
		{
			if (ITargetPlatformManagerModule* TPM = GetTargetPlatformManager())
			{
				TargetPlatform = TPM->FindTargetPlatform(SwitchValue);
				if (TargetPlatform == nullptr)
				{
					// @todo Error
				}

			}
			

		}
	}
}