UnrealEngineUWP/Engine/Plugins/Runtime/Metasound/Source/MetasoundEngineTest/Private/NodeTestGraphBuilder.cpp

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

#include "NodeTestGraphBuilder.h"
#include "Containers/Set.h"
#include "MetasoundFrontendGraph.h"
#include "MetasoundFrontendSearchEngine.h"
#include "MetasoundOperatorBuilder.h"

namespace Metasound::Test
{
	using namespace Frontend;

	FNodeTestGraphBuilder::FNodeTestGraphBuilder()
	{
		Document.RootGraph.Metadata.SetClassName({ "Metasound", "TestNodes", *LexToString(FGuid::NewGuid()) });
		Document.RootGraph.Metadata.SetType(EMetasoundFrontendClassType::Graph);

		DocumentHandle = IDocumentController::CreateDocumentHandle(Document);
		RootGraph = DocumentHandle->GetRootGraph();
		check(RootGraph->IsValid());
	}

	FNodeHandle FNodeTestGraphBuilder::AddNode(const FNodeClassName& ClassName, int32 MajorVersion) const
	{
		check(RootGraph->IsValid());

		FNodeHandle Node = INodeController::GetInvalidHandle();
		FMetasoundFrontendClass NodeClass;
		if (ISearchEngine::Get().FindClassWithHighestMinorVersion(ClassName, MajorVersion, NodeClass))
		{
			Node = RootGraph->AddNode(NodeClass.Metadata);
		}

		return Node;
	}

	FNodeHandle FNodeTestGraphBuilder::AddInput(const FName& InputName, const FName& TypeName) const
	{
		check(RootGraph->IsValid());

		FMetasoundFrontendClassInput Input;
		Input.Name = InputName;
		Input.TypeName = TypeName;
		Input.VertexID = FGuid::NewGuid();
		return RootGraph->AddInputVertex(Input);
	}

	FNodeHandle FNodeTestGraphBuilder::AddOutput(const FName& OutputName, const FName& TypeName)
	{
		check(RootGraph->IsValid());

		FMetasoundFrontendClassOutput Output;
		Output.Name = OutputName;
		Output.TypeName = TypeName;
		Output.VertexID = FGuid::NewGuid();
		FNodeHandle NodeHandle = RootGraph->AddOutputVertex(Output);

		static const FName AudioBufferTypeName = GetMetasoundDataTypeName<FAudioBuffer>();
		if (TypeName == AudioBufferTypeName)
		{
			AudioOutputNames.Add(OutputName);
		}

		return NodeHandle;
	}

	TUniquePtr<FMetasoundGenerator> FNodeTestGraphBuilder::BuildGenerator(FSampleRate SampleRate, int32 SamplesPerBlock) const
	{
		// Because a generator is tied to the concept of a source, go ahead and add the "OnPlay" input.
		// Otherwise we get warnings when we run our tests.
		AddInput(SourceInterface::Inputs::OnPlay, Metasound::GetMetasoundDataTypeName<FTrigger>());
		
		const TSet<FName> TransmittableInputNames;
		const FString UnknownAsset = TEXT("UnknownAsset");
		if (const TUniquePtr<FFrontendGraph> Graph = FFrontendGraphBuilder::CreateGraph(Document, TransmittableInputNames, UnknownAsset))
		{
			FOperatorBuilderSettings BuilderSettings;
			BuilderSettings.bFailOnAnyError = true;
			BuilderSettings.bPopulateInternalDataReferences = true;
			BuilderSettings.bValidateEdgeDataTypesMatch = true;
			BuilderSettings.bValidateNoCyclesInGraph = true;
			BuilderSettings.bValidateNoDuplicateInputs = true;
			BuilderSettings.bValidateOperatorOutputsAreBound = true;
			BuilderSettings.bValidateVerticesExist = true;

			const FOperatorSettings OperatorSettings{SampleRate, static_cast<float>(SampleRate) / SamplesPerBlock};

			FMetasoundEnvironment Environment;
			Environment.SetValue<uint64>(SourceInterface::Environment::TransmitterID, 123);
			
			FMetasoundGeneratorInitParams GeneratorInitParams{
				OperatorSettings,
				BuilderSettings,
				MakeShared<const FFrontendGraph, ESPMode::ThreadSafe>(*Graph),
				Environment,
				"TestMetasound",
				AudioOutputNames,
				TArray<FAudioParameter>(),
				true // bBuildSynchronous, so we don't have to do latent tasks
			};

			return MakeUnique<FMetasoundGenerator>(MoveTemp(GeneratorInitParams));
		}

		return nullptr;
	}

	TUniquePtr<FMetasoundGenerator> FNodeTestGraphBuilder::MakeSingleNodeGraph(
		const FNodeClassName& ClassName,
		const int32 MajorVersion,
		const FSampleRate SampleRate,
		const int32 SamplesPerBlock)
	{
		FNodeTestGraphBuilder Builder;
		FNodeHandle NodeHandle = Builder.AddNode(ClassName, MajorVersion);

		if (!NodeHandle->IsValid())
		{
			return nullptr;
		}

		// add the inputs and connect them
		for (FInputHandle Input : NodeHandle->GetInputs())
		{
			FNodeHandle InputNode = Builder.AddInput(Input->GetName(), Input->GetDataType());

			if (!InputNode->IsValid())
			{
				return nullptr;
			}

			FOutputHandle OutputToConnect = InputNode->GetOutputWithVertexName(Input->GetName());
			FInputHandle InputToConnect = NodeHandle->GetInputWithVertexName(Input->GetName());

			if (!InputToConnect->Connect(*OutputToConnect))
			{
				return nullptr;
			}
		}

		// add the outputs and connect them
		for (FOutputHandle Output : NodeHandle->GetOutputs())
		{
			FNodeHandle OutputNode = Builder.AddOutput(Output->GetName(), Output->GetDataType());

			if (!OutputNode->IsValid())
			{
				return nullptr;
			}

			FOutputHandle OutputToConnect = NodeHandle->GetOutputWithVertexName(Output->GetName());
			FInputHandle InputToConnect = OutputNode->GetInputWithVertexName(Output->GetName());

			if (!InputToConnect->Connect(*OutputToConnect))
			{
				return nullptr;
			}
		}

		// have to make an audio output for the generator to do anything
		if (Builder.AudioOutputNames.IsEmpty())
		{
			Builder.AddOutput("AudioOut", GetMetasoundDataTypeName<FAudioBuffer>());
		}

		// build the graph
		return Builder.BuildGenerator(SampleRate, SamplesPerBlock);
	}
}