// Copyright Epic Games, Inc. All Rights Reserved.
#include "MetasoundSource.h"

#include "AssetRegistryModule.h"
#include "CoreMinimal.h"
#include "Internationalization/Text.h"
#include "MetasoundAssetBase.h"
#include "MetasoundAudioFormats.h"
#include "MetasoundEngineArchetypes.h"
#include "MetasoundEngineEnvironment.h"
#include "MetasoundEnvironment.h"
#include "MetasoundFrontendController.h"
#include "MetasoundFrontendQuery.h"
#include "MetasoundFrontendQuerySteps.h"
#include "MetasoundFrontendSearchEngine.h"
#include "MetasoundFrontendTransform.h"
#include "MetasoundGenerator.h"
#include "MetasoundInstanceTransmitter.h"
#include "MetasoundLog.h"
#include "MetasoundOperatorSettings.h"
#include "MetasoundPrimitives.h"
#include "MetasoundReceiveNode.h"
#include "MetasoundTrigger.h"
#include "MetasoundUObjectRegistry.h"
#include "UObject/ObjectSaveContext.h"

#if WITH_EDITORONLY_DATA
#include "EdGraph/EdGraph.h"
#endif // WITH_EDITORONLY_DATA

#define LOCTEXT_NAMESPACE "MetaSoundSource"


FAutoConsoleVariableRef CVarMetaSoundBlockRate(
	TEXT("au.MetaSound.BlockRate"),
	Metasound::ConsoleVariables::BlockRate,
	TEXT("Sets block rate (blocks per second) of MetaSounds.\n")
	TEXT("Default: 100.0f"),
	ECVF_Default);

UMetaSoundSource::UMetaSoundSource(const FObjectInitializer& ObjectInitializer)
	: Super(ObjectInitializer)
	, FMetasoundAssetBase()
{
	bRequiresStopFade = true;
	NumChannels = 1;
	Duration = INDEFINITELY_LOOPING_DURATION;
	bLooping = true;
	
	// todo: ensure that we have a method so that the audio engine can be authoritative over the sample rate the UMetaSoundSource runs at.
	SampleRate = 48000.f;

}

#if WITH_EDITOR

void UMetaSoundSource::PreSave(FObjectPreSaveContext SaveContext)
{
	Super::PreSave(SaveContext);

	// TODO: Move these to be run anytime the interface changes or
	// the node is versioned

	//  TODO: Enable Composition
	// RegisterGraphWithFrontend();
}

void UMetaSoundSource::PostEditUndo()
{
	Super::PostEditUndo();

	if (Graph)
	{
		Graph->Synchronize();
	}
}

void UMetaSoundSource::PostEditChangeProperty(FPropertyChangedEvent& InEvent)
{
	using namespace Metasound;
	using namespace Metasound::Frontend;

	Super::PostEditChangeProperty(InEvent);
	Metasound::PostEditChangeProperty(*this, InEvent);

	if (InEvent.GetPropertyName() == GET_MEMBER_NAME_CHECKED(UMetaSoundSource, OutputFormat))
	{
		ConvertFromPreset();

		bool bDidModifyDocument = false;
		switch (OutputFormat)
		{
			case EMetasoundSourceAudioFormat::Mono:
			{
				NumChannels = 1;
				// TODO: utilize latest version `MetasoudnSourceMono`
				bDidModifyDocument = Metasound::Frontend::FMatchRootGraphToArchetype(Metasound::Engine::MetasoundSourceMono::GetVersion()).Transform(GetDocumentHandle());
			}
			break;

			case EMetasoundSourceAudioFormat::Stereo:
			{
				NumChannels = 2;
				bDidModifyDocument = Metasound::Frontend::FMatchRootGraphToArchetype(Metasound::Engine::MetasoundSourceStereo::GetVersion()).Transform(GetDocumentHandle());
			}
			break;

			default:
			{
				static_assert(static_cast<int32>(EMetasoundSourceAudioFormat::COUNT) == 2, "Possible missing format switch case coverage.");
			}
			break;
		}

		if (bDidModifyDocument)
		{
			MarkMetasoundDocumentDirty();
		}
	}
}
#endif // WITH_EDITOR

#if WITH_EDITORONLY_DATA
UEdGraph* UMetaSoundSource::GetGraph()
{
	return Graph;
}

const UEdGraph* UMetaSoundSource::GetGraph() const
{
	return Graph;
}

UEdGraph& UMetaSoundSource::GetGraphChecked()
{
	check(Graph);
	return *Graph;
}

const UEdGraph& UMetaSoundSource::GetGraphChecked() const
{
	check(Graph);
	return *Graph;
}

FText UMetaSoundSource::GetDisplayName() const
{
	FString TypeName = UMetaSoundSource::StaticClass()->GetName();
	return FMetasoundAssetBase::GetDisplayName(MoveTemp(TypeName));
}

void UMetaSoundSource::SetRegistryAssetClassInfo(const Metasound::Frontend::FNodeClassInfo& InNodeInfo)
{
	Metasound::SetMetaSoundRegistryAssetClassInfo(*this, InNodeInfo);
}
#endif // WITH_EDITORONLY_DATA

Metasound::Frontend::FNodeClassInfo UMetaSoundSource::GetAssetClassInfo() const
{
	return { GetDocumentChecked().RootGraph, *GetPathName() };
}

bool UMetaSoundSource::IsPlayable() const
{
	// todo: cache off whether this metasound is buildable to an operator.
	return true;
}

bool UMetaSoundSource::SupportsSubtitles() const
{
	return Super::SupportsSubtitles();
}

const FMetasoundFrontendVersion& UMetaSoundSource::GetDefaultArchetypeVersion() const
{
	static const FMetasoundFrontendVersion DefaultVersion = Metasound::Engine::MetasoundSourceMono::GetVersion();

	return DefaultVersion;
}

float UMetaSoundSource::GetDuration()
{
	// eh? this is kind of a weird field anyways.
	return Super::GetDuration();
}

ISoundGeneratorPtr UMetaSoundSource::CreateSoundGenerator(const FSoundGeneratorInitParams& InParams)
{
	using namespace Metasound;
	using namespace Metasound::Frontend;
	using namespace Metasound::Engine;

	Duration = INDEFINITELY_LOOPING_DURATION;
	bLooping = true;
	VirtualizationMode = EVirtualizationMode::PlayWhenSilent;

	SampleRate = InParams.SampleRate;
	FOperatorSettings InSettings = GetOperatorSettings(static_cast<FSampleRate>(SampleRate));
	FMetasoundEnvironment Environment;

	// Add audio device ID to environment.
	FAudioDeviceHandle DeviceHandle;
	if (UWorld* World = GetWorld())
	{
		DeviceHandle = World->GetAudioDevice();
	}
	if (!DeviceHandle.IsValid())
	{
		if (FAudioDeviceManager* DeviceManager = FAudioDeviceManager::Get())
		{
			DeviceHandle = DeviceManager->GetMainAudioDeviceHandle();
		}
	}
	Environment.SetValue<FAudioDeviceHandle>(MetasoundSource::GetAudioDeviceHandleVariableName(), DeviceHandle);
	Environment.SetValue<uint32>(MetasoundSource::GetSoundUniqueIdName(), GetUniqueID());
	Environment.SetValue<bool>(MetasoundSource::GetIsPreviewSoundName(), InParams.bIsPreviewSound);

	const FMetasoundFrontendDocument* OriginalDoc = GetDocument().Get();
	if (nullptr == OriginalDoc)
	{
		UE_LOG(LogMetaSound, Error, TEXT("Cannot create sound generator. Null Metasound document in UMetaSoundSource [Name:%s]"), *GetName());
		return ISoundGeneratorPtr(nullptr);
	}

	// Check version and attempt to version up if out-of-date
	if (VersionAsset(false /* bMarkDirty */))
	{
		const FMetasoundFrontendDocumentMetadata& Metadata = GetDocumentHandle()->GetMetadata();
		UE_LOG(LogMetaSound, Display,
			TEXT("Dynamically versioned UMetaSoundSource asset [Name:%s] to %s (Resave to avoid update at runtime)."),
			*GetName(),
			*Metadata.Version.Number.ToString());
	}

	// Inject receive nodes for unused transmittable inputs. Perform edits on a copy
	// of the document to avoid altering document.
	// TODO: Use a light wrapper of the document instead of a copy.
	FMetasoundFrontendDocument DocumentWithInjectedReceives;
	ensure(CopyDocumentAndInjectReceiveNodes(InParams.InstanceID, *OriginalDoc, DocumentWithInjectedReceives));

	// Create handles for new root graph
	FConstDocumentHandle NewDocumentHandle = IDocumentController::CreateDocumentHandle(MakeAccessPtr<FConstDocumentAccessPtr>(DocumentWithInjectedReceives.AccessPoint, DocumentWithInjectedReceives));

	FMetasoundGeneratorInitParams InitParams = 
	{
		InSettings,
		MoveTemp(DocumentWithInjectedReceives),
		Environment,
		GetName(),
		{}, // Channel names still need to be set.
		MetasoundSource::GetOnPlayInputName(),
		MetasoundSource::GetIsFinishedOutputName()
	};

	// Set init params dependent upon output audio format.
	switch (OutputFormat)
	{
		case EMetasoundSourceAudioFormat::Mono:
		{
			InitParams.AudioOutputNames = { MetasoundSourceMono::GetAudioOutputName() };
		}
		break;

		case EMetasoundSourceAudioFormat::Stereo:
		{
			InitParams.AudioOutputNames = { MetasoundSourceStereo::GetLeftAudioOutputName(), MetasoundSourceStereo::GetRightAudioOutputName() };
		}
		break;

		default:
		{
			static_assert(static_cast<int32>(EMetasoundSourceAudioFormat::COUNT) == 2, "Possible missing format switch case coverage.");
		}
		break;
	}

	return ISoundGeneratorPtr(new FMetasoundGenerator(MoveTemp(InitParams)));
}

TUniquePtr<IAudioInstanceTransmitter> UMetaSoundSource::CreateInstanceTransmitter(const FAudioInstanceTransmitterInitParams& InParams) const
{
	Metasound::FMetasoundInstanceTransmitter::FInitParams InitParams(GetOperatorSettings(InParams.SampleRate), InParams.InstanceID);

	for (const FSendInfoAndVertexName& InfoAndName : FMetasoundAssetBase::GetSendInfos(InParams.InstanceID))
	{
		InitParams.Infos.Add(InfoAndName.SendInfo);
	}

	return MakeUnique<Metasound::FMetasoundInstanceTransmitter>(InitParams);
}

Metasound::FOperatorSettings UMetaSoundSource::GetOperatorSettings(Metasound::FSampleRate InSampleRate) const
{
	const float BlockRate = FMath::Clamp(Metasound::ConsoleVariables::BlockRate, 1.0f, 1000.0f);
	return Metasound::FOperatorSettings(InSampleRate, BlockRate);
}

const TArray<FMetasoundFrontendVersion>& UMetaSoundSource::GetSupportedArchetypeVersions() const 
{
	static const TArray<FMetasoundFrontendVersion> Supported(
		{
			Metasound::Engine::MetasoundSourceMono::GetVersion(),
			Metasound::Engine::MetasoundSourceStereo::GetVersion()
		});

	return Supported;
}

#undef LOCTEXT_NAMESPACE // MetaSoundSource