/*
 * PROJECT: Alcyone System Kernel
 * LICENSE: BSD Clause 3
 * PURPOSE: Cache Controllerm, Cache  Utility Handler.
 * NT KERNEL: 5.11.9360
 * COPYRIGHT:  2023-2029 Dibymartanda Samanta <>
 */ 

class BitmapRangeManager {
private:
static constexpr LONGLONG CalculateBasePage(LONGLONG InputPage) {
        return (InputPage & ~(0x1000 - 1));
    }
public:
    static PBITMAP_RANGE FindBitmapRangeToDirty(PMBCB Mbcb, LONGLONG InputPage, PULONG* pBitmap) {
        PBITMAP_RANGE CurrentRange = nullptr;
        PBITMAP_RANGE NewRange = nullptr;
        PLIST_ENTRY HeadList = nullptr;
        LONGLONG BasePage = {0};


        HeadList = &Mbcb->BitmapRanges;
        BasePage = CalculateBasePage(InputPage);

        CurrentRange = CONTAINING_RECORD(Mbcb->BitmapRanges.Flink, BITMAP_RANGE, Links);

        while(true){
            if (BasePage == CurrentRange->BasePage)
                return CurrentRange;

            if (CurrentRange->DirtyPages || NewRange) {
                if (BasePage > CurrentRange->BasePage)
                    HeadList = &CurrentRange->Links;
            }
            else {
                NewRange = CurrentRange;
            }

            if (CurrentRange->Links.Flink == &Mbcb->BitmapRanges)
                break;

            CurrentRange = CONTAINING_RECORD(CurrentRange->Links.Flink, BITMAP_RANGE, Links);

            if (CurrentRange->BasePage > BasePage && NewRange)
                break;
        } 

        if (NewRange) {
            RemoveEntryList(&NewRange->Links);
        }
        else {
            NewRange = reinterpret_cast<PBITMAP_RANGE>(ExAllocatePoolWithTag(NonPagedPool, sizeof(*NewRange), 'rBcC'));
            if (!NewRange) {
                return nullptr;
            }

            RtlZeroMemory(NewRange, sizeof(*NewRange));
        }

        InsertHeadList(HeadList, &NewRange->Links);

        NewRange->BasePage = BasePage;
        NewRange->FirstDirtyPage = 0xFFFFFFFF;
        NewRange->LastDirtyPage = 0;

        if (!NewRange->Bitmap) {

            NewRange->Bitmap = *pBitmap;
            *pBitmap = nullptr;
        }

        return NewRange;
    }
};

/*  Internal Functions */
LONG
CcCopyReadExceptionFilter(
    _In_ PEXCEPTION_POINTERS ExceptionInfo,
    _Out_ NTSTATUS* OutStatus)
{
   

    NT_ASSERT(!NT_SUCCESS(*OutStatus));

    return EXCEPTION_EXECUTE_HANDLER;
}

PBITMAP_RANGE
NTAPI
CcFindBitmapRangeToDirty(
    _In_ PMBCB Mbcb,
    _In_ LONGLONG InputPage,
    _Inout_ PULONG* PBITMAP)
{
    return BitmapRangeManager::FindBitmapRangeToDirty(Mbcb, InputPage, pBitmap);
    
}

VOID
NTAPI
CcSetDirtyInMask(
    _In_ PSHARED_CACHE_MAP SharedMap,
    _In_ PLARGE_INTEGER FileOffset,
    _In_ ULONG Length)
{
    NT_DBGBREAK("UNIMPLEMENTED\n");
}

BOOLEAN
NTAPI
CcMapAndCopy(
    _In_ PSHARED_CACHE_MAP SharedMap,
    _In_ PVOID Buffer,
    _In_ PLARGE_INTEGER FileOffset,
    _In_ ULONG Length,
    _In_ ULONG CopyFlags,
    _In_ PFILE_OBJECT FileObject,
    _In_ PLARGE_INTEGER ValidDataLength,
    _In_ BOOLEAN Wait)
{ 
    NT_DBGBREAK("UNIMPLEMENTED\n");
}

/* EXTERNAL API FUNCTIONS */

BOOLEAN
NTAPI
CcCanIWrite(
    _In_ PFILE_OBJECT FileObject,
    _In_ ULONG BytesToWrite,
    _In_ BOOLEAN Wait,
    _In_ BOOLEAN IsRetrying)
{
     NT_DBGBREAK("UNIMPLEMENTED\n");
}



BOOLEAN
NTAPI
CcCopyRead(
    _In_ PFILE_OBJECT FileObject,
    _In_ PLARGE_INTEGER FileOffset,
    _In_ ULONG Length,
    _In_ BOOLEAN Wait,
    _Out_ PVOID Buffer,
    _Out_ IO_STATUS_BLOCK* OutIoStatus)
{
               NT_DBGBREAK("UNIMPLEMENTED\n");
}


BOOLEAN
NTAPI
CcCopyWrite(
    _In_ PFILE_OBJECT FileObject,
    _In_ PLARGE_INTEGER FileOffset,
    _In_ ULONG Length,
    _In_ BOOLEAN Wait,
    _In_ PVOID Buffer)
{
    NT_DBGBREAK("UNIMPLEMENTED\n");
}


VOID
NTAPI
CcDeferWrite(IN PFILE_OBJECT FileObject,
             IN PCC_POST_DEFERRED_WRITE PostRoutine,
             IN PVOID Context1,
             IN PVOID Context2,
             IN ULONG BytesToWrite,
             IN BOOLEAN Retrying)
{
    NT_DBGBREAK("UNIMPLEMENTED\n");
}


VOID
NTAPI
CcFastCopyRead(
    _In_ PFILE_OBJECT FileObject,
    _In_ ULONG FileOffset,
    _In_ ULONG Length,
    _In_ ULONG PageCount,
    _Out_ PVOID Buffer,
    _Out_ PIO_STATUS_BLOCK IoStatus)
{
    NT_DBGBREAK("UNIMPLEMENTED\n");
}


VOID
NTAPI
CcFastCopyWrite(
    _In_ PFILE_OBJECT FileObject,
    _In_ ULONG FileOffset,
    _In_ ULONG Length,
    _In_ PVOID InBuffer)
{
    NT_DBGBREAK("UNIMPLEMENTED\n");
}