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

#pragma once

#include "CoreTypes.h"
#include "Containers/ArrayView.h"
#include "Containers/StringFwd.h"
#include "DerivedDataBuildKey.h"
#include "DerivedDataRequestTypes.h"
#include "Features/IModularFeature.h"
#include "UObject/NameTypes.h"

class FCompressedBuffer;
struct FGuid;
struct FIoHash;

template <typename FuncType> class TFunctionRef;
template <typename FuncType> class TUniqueFunction;

namespace UE::DerivedData { class FBuildAction; }
namespace UE::DerivedData { class FBuildPolicy; }
namespace UE::DerivedData { class FOptionalBuildInputs; }
namespace UE::DerivedData { class FOptionalBuildOutput; }
namespace UE::DerivedData { class IBuild; }
namespace UE::DerivedData { class IRequestOwner; }
namespace UE::DerivedData { struct FBuildWorkerActionCompleteParams; }
namespace UE::DerivedData { struct FBuildWorkerFileDataCompleteParams; }

namespace UE::DerivedData
{

using FOnBuildWorkerActionComplete = TUniqueFunction<void (FBuildWorkerActionCompleteParams&& Params)>;
using FOnBuildWorkerFileDataComplete = TUniqueFunction<void (FBuildWorkerFileDataCompleteParams&& Params)>;

class FBuildWorker
{
public:
	virtual ~FBuildWorker() = default;
	virtual FStringView GetName() const = 0;
	virtual FStringView GetPath() const = 0;
	virtual FStringView GetHostPlatform() const = 0;
	virtual FGuid GetBuildSystemVersion() const = 0;
	virtual void FindFileData(TConstArrayView<FIoHash> RawHashes, IRequestOwner& Owner, FOnBuildWorkerFileDataComplete&& OnComplete) const = 0;
	virtual void IterateFunctions(TFunctionRef<void (FUtf8StringView Name, const FGuid& Version)> Visitor) const = 0;
	virtual void IterateFiles(TFunctionRef<void (FStringView Path, const FIoHash& RawHash, uint64 RawSize)> Visitor) const = 0;
	virtual void IterateExecutables(TFunctionRef<void (FStringView Path, const FIoHash& RawHash, uint64 RawSize)> Visitor) const = 0;
	virtual void IterateEnvironment(TFunctionRef<void (FStringView Name, FStringView Value)> Visitor) const = 0;
};

class FBuildWorkerBuilder
{
public:
	virtual ~FBuildWorkerBuilder() = default;
	virtual void SetName(FStringView Name) = 0;
	virtual void SetPath(FStringView Path) = 0;
	virtual void SetHostPlatform(FStringView Name) = 0;
	virtual void SetBuildSystemVersion(const FGuid& Version) = 0;
	virtual void AddFunction(FUtf8StringView Name, const FGuid& Version) = 0;
	virtual void AddFile(FStringView Path, const FIoHash& RawHash, uint64 RawSize) = 0;
	virtual void AddExecutable(FStringView Path, const FIoHash& RawHash, uint64 RawSize) = 0;
	virtual void SetEnvironment(FStringView Name, FStringView Value) = 0;
};

class IBuildWorkerFactory : public IModularFeature
{
public:
	static inline const FLazyName FeatureName{"BuildWorkerFactory"};

	virtual ~IBuildWorkerFactory() = default;

	virtual void Build(FBuildWorkerBuilder& Builder) = 0;
	virtual void FindFileData(TConstArrayView<FIoHash> RawHashes, IRequestOwner& Owner, FOnBuildWorkerFileDataComplete&& OnComplete) = 0;
};

class IBuildWorkerExecutor : public IModularFeature
{
public:
	static inline const FLazyName FeatureName{"BuildWorkerExecutor"};

	virtual ~IBuildWorkerExecutor() = default;

	virtual void Build(
		const FBuildAction& Action,
		const FOptionalBuildInputs& Inputs,
		const FBuildPolicy& Policy,
		const FBuildWorker& Worker,
		IBuild& BuildSystem,
		IRequestOwner& Owner,
		FOnBuildWorkerActionComplete&& OnComplete) = 0;

	virtual TConstArrayView<FStringView> GetHostPlatforms() const = 0;
};

struct FBuildWorkerActionCompleteParams
{
	FBuildActionKey Key;
	FOptionalBuildOutput&& Output;
	TConstArrayView<FUtf8StringView> MissingInputs;
	EStatus Status = EStatus::Error;
};

struct FBuildWorkerFileDataCompleteParams
{
	TConstArrayView<FCompressedBuffer> Files;
	EStatus Status = EStatus::Error;
};

} // UE::DerivedData