/***
    Copyright (C) 2023 J Reece Wilson (a/k/a "Reece"). All rights reserved.

    File: AuIOHandle.NT.cpp
    Date: 2023-7-28
    Author: Reece
***/
#include <RuntimeInternal.hpp>
#include "AuIOHandle.hpp"
#include "AuIOHandle.NT.hpp"

#include "FS/FS.hpp"
#include "FS/FileAdvisory.NT.hpp"

namespace Aurora::IO
{
    AuUInt64 AFileHandle::DupHandle(AuUInt64 uOSHandle, bool bWriteAccess)
    {
        HANDLE hTargetHandle = (HANDLE)uOSHandle;
        HANDLE hTargetProcess = ::GetCurrentProcess();
        HANDLE hHandle {};

        if (!::DuplicateHandle(hTargetProcess,
                               hTargetHandle,
                               hTargetProcess,
                               &hHandle,
                               bWriteAccess ? GENERIC_WRITE | GENERIC_READ : GENERIC_READ,
                               FALSE,
                               FALSE))
        {
            return 0;
        }

        return AuUInt64(hHandle);
    }

    void AFileHandle::CloseHandle(AuUInt64 uOSHandle)
    {
        HANDLE hHandle = (HANDLE)uOSHandle;
        AuWin32CloseHandle(hHandle);
    }

    struct NTIOHandle final : AFileHandle
    {
        bool InitFromPath(HandleCreate create) override;
    };

    bool NTIOHandle::InitFromPath(HandleCreate create)
    {
        HANDLE hFileHandle;

        DWORD dwFlags {};
        DWORD dwShare {};

        if (create.path.empty())
        {
            SysPushErrorArg("Cannot open an IO handle to the provided empty path");
            return false;
        }

        if (!FS::EFileOpenModeIsValid(create.eMode))
        {
            SysPushErrorParam("Invalid open mode");
            return false;
        }

        if (!FS::EFileAdvisoryLockLevelIsValid(create.eAdvisoryLevel))
        {
            SysPushErrorParam("Invalid lock mode");
            return false;
        }

        auto pathex = FS::NormalizePathRet(create.path);
        if (pathex.empty())
        {
            SysPushErrorMemory();
            return false;
        }

        auto win32Path = Locale::ConvertFromUTF8(pathex);
        if (win32Path.empty())
        {
            SysPushErrorMemory();
            return false;
        }

        hFileHandle = INVALID_HANDLE_VALUE;

        dwShare = FS::NtLockAdvisoryToShare(create.eAdvisoryLevel);

        if (create.bAsyncHandle)
        {
            dwFlags |= FILE_FLAG_OVERLAPPED;
        }

        if (create.bDirectIOMode)
        {
            dwFlags |= FILE_FLAG_NO_BUFFERING;
            this->bDirectIO = true;
        }
        
        if (!dwFlags)
        {
            dwFlags |= FILE_ATTRIBUTE_NORMAL;
        }

        switch (create.eMode)
        {
        case FS::EFileOpenMode::eRead:
        {
            hFileHandle = ::CreateFileW(win32Path.c_str(),
                                        GENERIC_READ,
                                        dwShare,
                                        NULL,
                                        OPEN_EXISTING,
                                        dwFlags,
                                        NULL);

            if (hFileHandle != INVALID_HANDLE_VALUE)
            {
                this->uOSReadHandle = AuUInt64(hFileHandle);
            }

            break;
        }
        case FS::EFileOpenMode::eReadWrite:
        {
            if (create.bAlwaysCreateDirTree)
            {
                FS::CreateDirectories(pathex, true);
            }

            if (create.bFailIfNonEmptyFile)
            {
                hFileHandle = ::CreateFileW(win32Path.c_str(),
                                            GENERIC_WRITE | GENERIC_READ | DELETE,
                                            NULL,
                                            NULL,
                                            CREATE_NEW,
                                            dwFlags,
                                            NULL);

                if (hFileHandle == INVALID_HANDLE_VALUE)
                {
                    if (AuFS::FileExists(pathex.c_str()))
                    {
                        SysPushErrorResourceExists("File {} already exists", create.path);
                        return false;
                    }
                }
            }
            else
            {
                hFileHandle = ::CreateFileW(win32Path.c_str(),
                                            GENERIC_WRITE | GENERIC_READ | DELETE,
                                            dwShare,
                                            NULL,
                                            OPEN_EXISTING,
                                            dwFlags,
                                            NULL);

                if (hFileHandle == INVALID_HANDLE_VALUE)
                {
                    hFileHandle = ::CreateFileW(win32Path.c_str(),
                                                GENERIC_WRITE | GENERIC_READ | DELETE,
                                                dwShare,
                                                NULL,
                                                CREATE_NEW,
                                                dwFlags,
                                                NULL);
                }
            }

            if (hFileHandle != INVALID_HANDLE_VALUE)
            {
                this->uOSReadHandle = AuUInt64(hFileHandle);
                this->uOSWriteHandle = AuUInt64(hFileHandle);
            }

            break;
        }
        case FS::EFileOpenMode::eWrite:
        {
            if (create.bAlwaysCreateDirTree)
            {
                FS::CreateDirectories(pathex, true);
            }

            if (create.bFailIfNonEmptyFile)
            {
                hFileHandle = ::CreateFileW(win32Path.c_str(),
                                            GENERIC_WRITE | DELETE,
                                            NULL,
                                            NULL,
                                            CREATE_NEW,
                                            dwFlags,
                                            NULL);

                if (hFileHandle == INVALID_HANDLE_VALUE)
                {
                    if (AuFS::FileExists(pathex.c_str()))
                    {
                        SysPushErrorResourceExists("File {} already exists", create.path);
                        return false;
                    }
                }
            }
            else
            {
                hFileHandle = ::CreateFileW(win32Path.c_str(),
                                            GENERIC_WRITE | FILE_READ_ATTRIBUTES | DELETE,
                                            dwShare, 
                                            NULL,
                                            OPEN_EXISTING,
                                            dwFlags,
                                            NULL);

                if (hFileHandle == INVALID_HANDLE_VALUE)
                {
                    hFileHandle = ::CreateFileW(win32Path.c_str(),
                                                GENERIC_WRITE | DELETE,
                                                dwShare,
                                                NULL,
                                                CREATE_NEW,
                                                dwFlags,
                                                NULL);
                }
            }

            if (hFileHandle != INVALID_HANDLE_VALUE)
            {
                this->uOSWriteHandle = AuUInt64(hFileHandle);
            }

            break;
        }
        }

        if (hFileHandle == INVALID_HANDLE_VALUE)
        {
            SysPushErrorIO("Couldn't open: {}", create.path);
            return false;
        }

        this->bIsAsync = create.bAsyncHandle;

        this->path = create.path;

        return this->IsValid();
    }

    AUKN_SYM bool IsHandleTTY(AuUInt uHandle)
    {
        bool bIsPipe {};
        DWORD dwType {};

        if (!uHandle ||
            uHandle == (AuUInt)INVALID_HANDLE_VALUE)
        {
            SysPushErrorArg();
            return false;
        }

        if (!(dwType = ::GetFileType((HANDLE)uHandle)))
        {
            SysPushErrorGeneric();
            return {};
        }

        return dwType == FILE_TYPE_CHAR;
    }

    AUKN_SYM bool IsHandlePipe(AuUInt uHandle)
    {
        bool bIsPipe {};
        DWORD dwType {};

        if (!uHandle ||
            uHandle == (AuUInt)INVALID_HANDLE_VALUE)
        {
            SysPushErrorArg();
            return false;
        }

        if (!(dwType = ::GetFileType((HANDLE)uHandle)))
        {
            SysPushErrorGeneric();
            return {};
        }

        return dwType == FILE_TYPE_PIPE;
    }

    AUKN_SYM bool IsHandleFile(AuUInt uHandle)
    {
        bool bIsPipe {};
        DWORD dwType {};

        if (!uHandle ||
            uHandle == (AuUInt)INVALID_HANDLE_VALUE)
        {
            SysPushErrorArg();
            return false;
        }

        if (!(dwType = ::GetFileType((HANDLE)uHandle)))
        {
            SysPushErrorGeneric();
            return {};
        }

        return dwType == FILE_TYPE_DISK;
    }

    AUKN_SYM IIOHandle *IOHandleNew()
    {
        return _new NTIOHandle();
    }

    AUKN_SYM void IOHandleRelease(IIOHandle *pIOHandle)
    {
        AuSafeDelete<NTIOHandle *>(pIOHandle);
    }

    AUROXTL_INTERFACE_SOO_SRC_EX(AURORA_SYMBOL_EXPORT, IOHandle, NTIOHandle)
}