// Fill out your copyright notice in the Description page of Project Settings.

#include "Game/ShooterGameMode.h"
#include "GenericPlatform/GenericPlatformMisc.h"
#include "Containers/UnrealString.h"
#include "GameLiftClpTypes.h"
#include "GameLift/GameLiftClp.h"
#include "openssl/sha.h"
#include "GameLiftServerSDK.h"
#include "GameLiftServerSDKModels.h"



DEFINE_LOG_CATEGORY(LogShooterGameMode);

//  Function implementations.

AShooterGameMode::AShooterGameMode()
{
}

void AShooterGameMode::BeginPlay()
{
	Super::BeginPlay();
#if WITH_GAMELIFT
	InitGameLift();
#endif
}

void AShooterGameMode::InitGame(const FString& MapName, const FString& Options, FString& ErrorMessage)
{
	Super::InitGame(MapName, Options, ErrorMessage);
	CachedCommandLine = FCommandLine::Get();
	
	const FPortResult PortResult = cmdlineparser::details::GetConfiguredOrDefaultPort(CachedCommandLine, TEXT("port"));;
	if (PortResult.bUsedDefaultPort)
	{
		UE_LOGFMT (LogShooterGameMode, Warning, "{0}", PortResult.WarningMessage);
	}
	
	GameLiftConfig.ServerPort = PortResult.Port;
	if (FParse::Param(*CachedCommandLine, TEXT("glAnywhereFleet")))
	{
		UE_LOGFMT(LogShooterGameMode, Log, "Fleet type: Anywhere");
		GameLiftConfig.bIsAnywhereFleet = true;
		GameLiftConfig.bAllOptionsFound = GetAnywhereFleetParameters(CachedCommandLine);
		LogAnywhereFleetParameters();
	}
	else
	{
		UE_LOGFMT(LogShooterGameMode, Log, "Fleet type: EC2");
		// TODO: EC2 configuration
	}
}

FString AShooterGameMode::GetSHA256Hash(const FString& InString)
{
	
	if (InString.IsEmpty()) 
		return TEXT("e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855");

	FSHA256Signature Hash;
	
	// Use OpenSSL to compute the SHA-256 hash
	
	FTCHARToUTF8 Utf8(InString);
	const uint8* Bytes = reinterpret_cast<const uint8*>(Utf8.Get());
	uint32 Length = Utf8.Length();
	
	
	SHA256_CTX Sha256Context;
	SHA256_Init(&Sha256Context);
	SHA256_Update(&Sha256Context, Bytes,Length);
	SHA256_Final(Hash.Signature, &Sha256Context);
	
	return Hash.ToString();
}

void AShooterGameMode::InitGameLift()
{
#if WITH_GAMELIFT
	UE_LOGFMT(LogShooterGameMode, Log, "Calling InitGameLift...");
	
	//  Get the module first
	FGameLiftServerSDKModule* GameLiftSdkModule = &FModuleManager::LoadModuleChecked<FGameLiftServerSDKModule>("GameLiftServerSDK");
	FGameLiftGenericOutcome InitSdkOutcome;

	UE_LOGFMT(LogShooterGameMode, Log, "Initializing the GameLift Server...");
	if (GameLiftConfig.bIsAnywhereFleet)
	{
		//  Define the server parameters for an Anywhere fleet.  These are not needed for a GameLift managed EC2 fleet.
		FServerParameters ServerParametersForAnywhere;

		uint32 PID = FPlatformProcess::GetCurrentProcessId();
		FString PIDString = FString::FromInt(static_cast<int32>(PID));
		
		UE_LOGFMT(LogShooterGameMode, Log, "Configuring server parameters for Anywhere...");
		//  If AnywhereFleets are being used load the command line arguments parsed earlier.
		ServerParametersForAnywhere.m_webSocketUrl = TCHAR_TO_UTF8(*GameLiftConfig.WebSocketUrlResult.Value);
		ServerParametersForAnywhere.m_fleetId = TCHAR_TO_UTF8((*GameLiftConfig.FleetIdResult.Value));
		ServerParametersForAnywhere.m_hostId = TCHAR_TO_UTF8(*GameLiftConfig.HostIdResult.Value);
		ServerParametersForAnywhere.m_processId = PIDString;
		ServerParametersForAnywhere.m_authToken = TCHAR_TO_UTF8(*GameLiftConfig.AuthTokenResult.Value);
		LogServerParameters(ServerParametersForAnywhere);
		
		//  InitSDK will establish a local connection with GameLift's agent to enable further communication.
		InitSdkOutcome = GameLiftSdkModule->InitSDK(ServerParametersForAnywhere);
	}
	else
	{
		InitSdkOutcome = GameLiftSdkModule->InitSDK();
	}
	
	if (InitSdkOutcome.IsSuccess())
	{
		UE_LOG(LogShooterGameMode, SetColor, TEXT("%s"), COLOR_GREEN);
		UE_LOG(LogShooterGameMode, Log, TEXT("GameLift InitSDK succeeded!"));
		UE_LOG(LogShooterGameMode, SetColor, TEXT("%s"), COLOR_NONE);
	}
	else
	{
		UE_LOG(LogShooterGameMode, SetColor, TEXT("%s"), COLOR_RED);
		UE_LOG(LogShooterGameMode, Log, TEXT("ERROR: InitSDK failed : ("));
		FGameLiftError GameLiftError = InitSdkOutcome.GetError();
		UE_LOG(LogShooterGameMode, Log, TEXT("ERROR: %s"), *GameLiftError.m_errorMessage);
		UE_LOG(LogShooterGameMode, SetColor, TEXT("%s"), COLOR_NONE);
		return;
	}
		
	ProcessParameters = MakeShared<FProcessParameters>();
	//When a game session is created, Amazon GameLift Servers sends an activation request to the game server and passes along the game session object containing game properties and other settings.
	//Here is where a game server should take action based on the game session object.
	//Once the game server is ready to receive incoming player connections, it should invoke GameLiftServerAPI.ActivateGameSession()
	// ReSharper disable once CppPassValueParameterByConstReference - not safe to do with async lambdas
	ProcessParameters->OnStartGameSession.BindLambda([=](Aws::GameLift::Server::Model::GameSession InGameSession)
    {
		const FString GameSessionId = FString(InGameSession.GetGameSessionId());
        UE_LOG(LogShooterGameMode, Log, TEXT("GameSession Initializing: %s"), *GameSessionId);
        GameLiftSdkModule->ActivateGameSession();
    });

    //OnProcessTerminate callback. Amazon GameLift Servers will invoke this callback before shutting down an instance hosting this game server.
    //It gives this game server a chance to save its state, communicate with services, etc., before being shut down.
    //In this case, we simply tell Amazon GameLift Servers we are indeed going to shut down.
	ProcessParameters->OnTerminate.BindLambda([=]()
    {
		UE_LOG(LogShooterGameMode, Log, TEXT("Game Server Process is terminating"));
        // First call ProcessEnding()
        FGameLiftGenericOutcome processEndingOutcome = GameLiftSdkModule->ProcessEnding();
        // Then call Destroy() to free the SDK from memory
        FGameLiftGenericOutcome destroyOutcome = GameLiftSdkModule->Destroy();
        // Exit the process with success or failure
        if (processEndingOutcome.IsSuccess() && destroyOutcome.IsSuccess()) {
            UE_LOG(LogShooterGameMode, Log, TEXT("Server process ending successfully"));
        }
        else {
            if (!processEndingOutcome.IsSuccess()) {
                const FGameLiftError& error = processEndingOutcome.GetError();
                UE_LOG(LogShooterGameMode, Error, TEXT("ProcessEnding() failed. Error: %s"),
                error.m_errorMessage.IsEmpty() ? TEXT("Unknown error") : *error.m_errorMessage);
            }
            if (!destroyOutcome.IsSuccess()) {
                const FGameLiftError& error = destroyOutcome.GetError();
                UE_LOG(LogShooterGameMode, Error, TEXT("Destroy() failed. Error: %s"),
                error.m_errorMessage.IsEmpty() ? TEXT("Unknown error") : *error.m_errorMessage);
            }
        }
		GLog->Flush();
		FGenericPlatformMisc::RequestExit(false);
    });
         
    //This is the Health Check callback.
    //Amazon GameLift Servers will invoke this callback every 60 seconds or so.
    //Here, a game server might want to check the health of dependencies and such.
    //Simply return true if healthy, false otherwise.
    //The game server has 60 seconds to respond with its health status. Amazon GameLift Servers will default to 'false' if the game server doesn't respond in time.
    //In this case, we're always healthy!
	ProcessParameters->OnHealthCheck.BindLambda([]()
    {
        UE_LOG(LogShooterGameMode, Log, TEXT("Performing Health Check"));
        return true;
    });
		
	ProcessParameters->port = GameLiftConfig.ServerPort;
		
	TArray<FString> Logfiles;
	Logfiles.Add(TEXT("FPSTemplate/Saved/Log/server.log"));
	ProcessParameters->logParameters = Logfiles;
		
	UE_LOGFMT(LogShooterGameMode, Log, "Calling Process Ready...");
	FGameLiftGenericOutcome ProcessReadyOutcome = GameLiftSdkModule->ProcessReady(*ProcessParameters);
		
	if (ProcessReadyOutcome.IsSuccess())
	{
		UE_LOG(LogShooterGameMode, SetColor, TEXT("%s"), COLOR_GREEN);
		UE_LOG(LogShooterGameMode, Log, TEXT("Process Ready!"));
		UE_LOG(LogShooterGameMode, SetColor, TEXT("%s"), COLOR_NONE);
	}
	else
	{
		UE_LOG(LogShooterGameMode, SetColor, TEXT("%s"), COLOR_RED);
		UE_LOG(LogShooterGameMode, Log, TEXT("ERROR: Process Ready Failed!"));
		FGameLiftError ProcessReadyError = ProcessReadyOutcome.GetError();
		UE_LOG(LogShooterGameMode, Log, TEXT("ERROR: %s"), *ProcessReadyError.m_errorMessage);
		UE_LOG(LogShooterGameMode, SetColor, TEXT("%s"), COLOR_NONE);
		return;
	}
		
	UE_LOGFMT(LogShooterGameMode, Log, "InitGameLift completed!");
	
#endif
}

bool AShooterGameMode::GetAnywhereFleetParameters(const FString& CommandLineString)
{
	bool bAllAnywhereFleetParametersValid = true;
	GameLiftConfig.AuthTokenResult = cmdlineparser::GetValueOfToken(CommandLineString, cmdlineparser::details::EAvailableTokens::AuthToken);
	if (!GameLiftConfig.AuthTokenResult.bIsValid) bAllAnywhereFleetParametersValid = false;
	
	GameLiftConfig.FleetIdResult = cmdlineparser::GetValueOfToken(CommandLineString, cmdlineparser::details::EAvailableTokens::FleetId);
	if (!GameLiftConfig.FleetIdResult.bIsValid) bAllAnywhereFleetParametersValid = false;
	
	GameLiftConfig.HostIdResult = cmdlineparser::GetValueOfToken(CommandLineString, cmdlineparser::details::EAvailableTokens::HostId);
	if (!GameLiftConfig.HostIdResult.bIsValid) bAllAnywhereFleetParametersValid = false;

	GameLiftConfig.WebSocketUrlResult = cmdlineparser::GetValueOfToken(CommandLineString, cmdlineparser::details::EAvailableTokens::WebsocketUrl);
	if (!GameLiftConfig.WebSocketUrlResult.bIsValid) bAllAnywhereFleetParametersValid = false;
	
	return bAllAnywhereFleetParametersValid;
}

void AShooterGameMode::LogAnywhereFleetParameters()
{
	// Lambda for getting the token name from token
	auto GetTokenName = [](const cmdlineparser::details::FParseResult& Result) -> FString
	{
		return cmdlineparser::details::CLI_TOKENS[static_cast<int32>(Result.Token)];
	};
	
	UE_LOGFMT(LogShooterGameMode, Log, "Anywhere Fleet Parameters:");
	if (GameLiftConfig.AuthTokenResult.bIsValid)
	{
		UE_LOGFMT(LogShooterGameMode, Log, "AuthToken: {0}", GetValueOrHash(GameLiftConfig.AuthTokenResult.Value));
	}
	else
	{
		UE_LOGFMT(
			LogShooterGameMode, 
			Error, 
			"AuthToken: {0}", 
			FString::Format(
				*GameLiftConfig.AuthTokenResult.ErrorMessage, 
				{
					FStringFormatArg(GetTokenName(GameLiftConfig.AuthTokenResult)), 
					FStringFormatArg(GetValueOrHash(GameLiftConfig.AuthTokenResult.Value)),
				}
			)
		);
	}
	
	if (GameLiftConfig.FleetIdResult.bIsValid)
	{
		UE_LOGFMT(LogShooterGameMode, Log, "FleetId: {0}", GameLiftConfig.FleetIdResult.Value);
	}
	else
	{
		UE_LOGFMT(
			LogShooterGameMode, 
			Error, 
			"FleetId: {0}", 
			FString::Format(
				*GameLiftConfig.FleetIdResult.ErrorMessage, 
				{
					FStringFormatArg(GetTokenName(GameLiftConfig.FleetIdResult)), 
					FStringFormatArg(GameLiftConfig.FleetIdResult.Value)
				}
			)
		);
	}
	
	if (GameLiftConfig.HostIdResult.bIsValid)
	{
		UE_LOGFMT(LogShooterGameMode, Log, "HostId: {0}", GameLiftConfig.HostIdResult.Value);
	}
	else
	{
		UE_LOGFMT(
			LogShooterGameMode, 
			Error, 
			"HostId: {0}", 
			FString::Format(
				*GameLiftConfig.HostIdResult.ErrorMessage, 
				{
					FStringFormatArg(GetTokenName(GameLiftConfig.HostIdResult)), 
					FStringFormatArg(GameLiftConfig.HostIdResult.Value)
				}
			)
		);
	}
	
	if (GameLiftConfig.WebSocketUrlResult.bIsValid)
	{
		UE_LOGFMT(LogShooterGameMode, Log, "WebSocketUrl: {0}", GameLiftConfig.WebSocketUrlResult.Value);
	}
	else
	{
		UE_LOGFMT(
			LogShooterGameMode, 
			Error, 
			"WebSocketUrl: {0}", 
			FString::Format(
				*GameLiftConfig.WebSocketUrlResult.ErrorMessage, 
				{
					FStringFormatArg(GetTokenName(GameLiftConfig.WebSocketUrlResult)), 
					FStringFormatArg(GameLiftConfig.WebSocketUrlResult.Value)
				}
			)
		);
	}
	
	UE_LOGFMT(LogShooterGameMode, Log, "Server Port: {0}", GameLiftConfig.ServerPort);
	
	if (GameLiftConfig.bAllOptionsFound)
	{
		UE_LOGFMT(LogShooterGameMode, Log, "Anywhere Fleet Parameters Loaded Successfully....");
	}
	else
	{
		UE_LOGFMT(LogShooterGameMode, Error, "Anywhere Fleet Parameters Load FAILED....");
	}
}

void AShooterGameMode::LogServerParameters(const FServerParameters& InServerParameters)
{

	UE_LOGFMT(LogShooterGameMode, Log, ">>>> WebSocket URL: {WebSocketUrl}", InServerParameters.m_webSocketUrl);
	UE_LOGFMT(LogShooterGameMode, Log, ">>>> Fleet ID: {FleetId}", InServerParameters.m_fleetId);
	UE_LOGFMT(LogShooterGameMode, Log, ">>>> Process ID: {ProcessId}", InServerParameters.m_processId);
	UE_LOGFMT(LogShooterGameMode, Log, ">>>> Host ID (Compute Name): {HostId}", InServerParameters.m_hostId);
	UE_LOGFMT(LogShooterGameMode, Log, ">>>> Auth Token: {AuthToken}", GetValueOrHash(InServerParameters.m_authToken));
	
	if (!InServerParameters.m_awsRegion.IsEmpty())
	{
		UE_LOGFMT(LogShooterGameMode, Log, ">>>> Aws Region: {AwsRegion}", InServerParameters.m_awsRegion);
	}
	
	if (!InServerParameters.m_accessKey.IsEmpty())
	{
		UE_LOGFMT(LogShooterGameMode, Log, ">>>> Access Key: {AccessKey}", GetValueOrHash(InServerParameters.m_accessKey));
	}
	
	if (!InServerParameters.m_secretKey.IsEmpty())
	{
		UE_LOGFMT(LogShooterGameMode, Log, ">>>> Secret Key: {SecretKey}", GetValueOrHash(InServerParameters.m_secretKey));
	}
	
	if (!InServerParameters.m_sessionToken.IsEmpty())
	{
		UE_LOGFMT(LogShooterGameMode, Log, ">>>> Session Token: {SessionToken}", GetValueOrHash(InServerParameters.m_sessionToken));
	}
}

FString AShooterGameMode::GetValueOrHash(const FString& Value)
{
#if UE_BUILD_DEBUG || UE_BUILD_DEVELOPMENT
	return Value;
#else
	return TEXT("HASH:") + GetSHA256Hash(Value);
#endif
}