/***
    Copyright (C) 2021 J Reece Wilson (a/k/a "Reece"). All rights reserved.

    File: Async.NT.hpp
    Date: 2021-9-13
    Author: Reece
***/
#pragma once

namespace Aurora::IO::IPC
{
    struct IPCPipeImpl;
}

namespace Aurora::IO::FS
{
    struct NtAsyncFileStream : IAsyncFileStream
    {
        AuSPtr<IAsyncTransaction> NewTransaction() override;

        bool BlockingTruncate(AuUInt64 length) override;
        bool BlockingRead(AuUInt64 offset, const Memory::MemoryViewStreamWrite &parameters) override;
        bool BlockingWrite(AuUInt64 offset, const Memory::MemoryViewStreamRead &parameters) override;

        void Init(const AuSPtr<IIOHandle> &pHandle);

        AuSPtr<IIOHandle> GetHandle();

    private:
        AuSPtr<IIOHandle> pHandle_;
        AuSPtr<IFileStream> pCache_;
    };

    struct NtAsyncFileTransaction :
        IAsyncTransaction,
        CompletionGroup::ICompletionGroupWorkItem,
        AuEnableSharedFromThis<NtAsyncFileTransaction>
    {
        ~NtAsyncFileTransaction();

        bool Init(const AuSPtr<IIOHandle> &handle);
        bool InitWeak(const AuSPtr<IIOHandle> &handle);
        void ResetAIO();

        bool StartRead(AuUInt64 offset, const AuMemoryViewWrite &memoryView) override;
        bool StartWrite(AuUInt64 offset, const AuMemoryViewRead &memoryView) override;

        bool     isIrredeemable_ {};

        bool     HasCompleted() override;

        bool     Complete() override;

        bool HasCompletedForGCWI() override;
        void CleanupForGCWI() override;

        bool CompleteEx(AuUInt completeRoutine, bool bForce = false);

        bool     HasFailed() override;
        AuUInt   GetOSErrorCode() override;

        AuUInt32 GetLastPacketLength() override;

        void SetCallback(const AuSPtr<IAsyncFinishedSubscriber> &sub) override;

        void SetBaseOffset(AuUInt64 uBaseOffset) override;

        bool Wait(AuUInt32 timeout) override;
        AuSPtr<AuLoop::ILoopSource> NewLoopSource() override;

        void Reset() override;
        
        bool TryAttachToCompletionGroup(const AuSPtr<CompletionGroup::ICompletionGroup> &pCompletionGroup) override;
        CompletionGroup::ICompletionGroupWorkHandle *ToCompletionGroupHandle() override;
        AuSPtr<CompletionGroup::ICompletionGroup> GetCompletionGroup() override;

        bool IDontWannaUsePorts();

        void DispatchCb(AuUInt32 len);

        void RoutineCallCB(AuUInt32 len);
    #if defined(__AUHAS_COROUTINES_CO_AWAIT) && defined(AU_LANG_CPP_20_)
        AuVoidTask RoutineCallCB_(AuUInt32 len);
    #endif

        HANDLE GetHandle();
        AuSPtr<IIOHandle> GetFileHandle();

        OVERLAPPED overlap {};
        HANDLE   event = INVALID_HANDLE_VALUE;
        AuSPtr<NtAsyncFileTransaction> pPin;
        AuUInt32 dwLastAbstractStat {};
        AuUInt64 qwLastAbstractOffset {};
        bool     bLatch {};
        AuUInt32 dwLastBytes {};
        AuUInt32 dwOsErrorCode {};
        bool     bHasFailed {};
        AuUInt64 uBaseOffset {};

        AuWPtr<Aurora::IO::IPC::IPCPipeImpl> pNtIpcPipeImpl;
        AuMemoryViewRead readView;
        AuMemoryViewWrite writeView;

    private:
        AuSPtr<IIOHandle> pHandle_;
        AuWPtr<IIOHandle> wpHandle_;
        AuSPtr<IAsyncFinishedSubscriber> pSub_;
        bool bOwnsEvent_ { true };
        AuSPtr<CompletionGroup::ICompletionGroup> pCompletionGroup_;
    };
}