/*
 * PROJECT:     ReactOS Setup Library
 * LICENSE:     GPL-2.0+ (https://spdx.org/licenses/GPL-2.0+)
 * PURPOSE:     Filesystem support functions
 * COPYRIGHT:   Copyright 2003-2018 Casper S. Hornstrup (chorns@users.sourceforge.net)
 *              Copyright 2017-2018 Hermes Belusca-Maito
 */

//
// This is basically the code for listing available FileSystem providers
// (currently hardcoded in a list), and for performing a basic FileSystem
// recognition for a given disk partition.
//
// See also: https://git.reactos.org/?p=reactos.git;a=blob;f=reactos/dll/win32/fmifs/init.c;h=e895f5ef9cae4806123f6bbdd3dfed37ec1c8d33;hb=b9db9a4e377a2055f635b2fb69fef4e1750d219c
// for how to get FS providers in a dynamic way. In the (near) future we may
// consider merging some of this code with us into a fmifs / fsutil / fslib library...
//

/* INCLUDES *****************************************************************/

#include "precomp.h"

#include "fsutil.h"
#include "partlist.h"

#include <fslib/vfatlib.h>
#include <fslib/btrfslib.h>
// #include <fslib/ext2lib.h>
// #include <fslib/ntfslib.h>

#define NDEBUG
#include <debug.h>


FILE_SYSTEM RegisteredFileSystems[] =
{
    { L"FAT"  , VfatFormat, VfatChkdsk },
//  { L"FAT32", VfatFormat, VfatChkdsk },
#if 0
    { L"FATX" , VfatxFormat, VfatxChkdsk },
    { L"NTFS" , NtfsFormat, NtfsChkdsk },

    { L"EXT2" , Ext2Format, Ext2Chkdsk },
    { L"EXT3" , Ext2Format, Ext2Chkdsk },
    { L"EXT4" , Ext2Format, Ext2Chkdsk },
#endif
    { L"BTRFS", BtrfsFormatEx, BtrfsChkdskEx },
#if 0
    { L"FFS"  , FfsFormat , FfsChkdsk  },
    { L"REISERFS", ReiserfsFormat, ReiserfsChkdsk },
#endif
};


/* FUNCTIONS ****************************************************************/

PFILE_SYSTEM
GetRegisteredFileSystems(OUT PULONG Count)
{
    *Count = ARRAYSIZE(RegisteredFileSystems);
    return RegisteredFileSystems;
}

PFILE_SYSTEM
GetFileSystemByName(
    // IN PFILE_SYSTEM_LIST List,
    IN PCWSTR FileSystemName)
{
#if 0 // Reenable when the list of registered FSes will again be dynamic

    PLIST_ENTRY ListEntry;
    PFILE_SYSTEM_ITEM Item;

    ListEntry = List->ListHead.Flink;
    while (ListEntry != &List->ListHead)
    {
        Item = CONTAINING_RECORD(ListEntry, FILE_SYSTEM_ITEM, ListEntry);
        if (Item->FileSystemName && wcsicmp(FileSystemName, Item->FileSystemName) == 0)
            return Item;

        ListEntry = ListEntry->Flink;
    }

#else

    ULONG Count;
    PFILE_SYSTEM FileSystems;

    FileSystems = GetRegisteredFileSystems(&Count);
    if (!FileSystems || Count == 0)
        return NULL;

    while (Count--)
    {
        if (FileSystems->FileSystemName && wcsicmp(FileSystemName, FileSystems->FileSystemName) == 0)
            return FileSystems;

        ++FileSystems;
    }

#endif

    return NULL;
}


//
// FileSystem recognition (using NT OS functionality)
//

#if 0 // FIXME: To be fully enabled when our storage stack & al. will work better!

/* NOTE: Ripped & adapted from base/system/autochk/autochk.c */
static NTSTATUS
_MyGetFileSystem(
    IN struct _PARTENTRY* PartEntry,
    IN OUT PWSTR FileSystemName,
    IN SIZE_T FileSystemNameSize)
{
    NTSTATUS Status;
    HANDLE FileHandle;
    IO_STATUS_BLOCK IoStatusBlock;
    PFILE_FS_ATTRIBUTE_INFORMATION FileFsAttribute;
    UCHAR Buffer[sizeof(FILE_FS_ATTRIBUTE_INFORMATION) + MAX_PATH * sizeof(WCHAR)];

    OBJECT_ATTRIBUTES ObjectAttributes;
    UNICODE_STRING PartitionRootPath;
    WCHAR PathBuffer[MAX_PATH];

    FileFsAttribute = (PFILE_FS_ATTRIBUTE_INFORMATION)Buffer;

    /* Set PartitionRootPath */
    RtlStringCchPrintfW(PathBuffer, ARRAYSIZE(PathBuffer),
                        // L"\\Device\\Harddisk%lu\\Partition%lu", // Should work! But because ReactOS sucks atm. it actually doesn't work!!
                        L"\\Device\\Harddisk%lu\\Partition%lu\\",  // HACK: Use this as a temporary hack!
                        PartEntry->DiskEntry->DiskNumber,
                        PartEntry->PartitionNumber);
    RtlInitUnicodeString(&PartitionRootPath, PathBuffer);
    DPRINT("PartitionRootPath: %wZ\n", &PartitionRootPath);

    /* Open the partition */
    InitializeObjectAttributes(&ObjectAttributes,
                               &PartitionRootPath,
                               OBJ_CASE_INSENSITIVE,
                               NULL,
                               NULL);
    Status = NtOpenFile(&FileHandle, // PartitionHandle,
                        FILE_GENERIC_READ /* | SYNCHRONIZE */,
                        &ObjectAttributes,
                        &IoStatusBlock,
                        FILE_SHARE_READ,
                        0 /* FILE_SYNCHRONOUS_IO_NONALERT */);
    if (!NT_SUCCESS(Status))
    {
        DPRINT1("Failed to open partition %wZ, Status 0x%08lx\n", &PartitionRootPath, Status);
        return Status;
    }

    /* Retrieve the FS attributes */
    Status = NtQueryVolumeInformationFile(FileHandle,
                                          &IoStatusBlock,
                                          FileFsAttribute,
                                          sizeof(Buffer),
                                          FileFsAttributeInformation);
    NtClose(FileHandle);

    if (!NT_SUCCESS(Status))
    {
        DPRINT1("NtQueryVolumeInformationFile failed for partition %wZ, Status 0x%08lx\n", &PartitionRootPath, Status);
        return Status;
    }

    if (FileSystemNameSize * sizeof(WCHAR) < FileFsAttribute->FileSystemNameLength + sizeof(WCHAR))
        return STATUS_BUFFER_TOO_SMALL;

    RtlCopyMemory(FileSystemName,
                  FileFsAttribute->FileSystemName,
                  FileFsAttribute->FileSystemNameLength);
    FileSystemName[FileFsAttribute->FileSystemNameLength / sizeof(WCHAR)] = UNICODE_NULL;

    return STATUS_SUCCESS;
}

#endif

PFILE_SYSTEM
GetFileSystem(
    // IN PFILE_SYSTEM_LIST FileSystemList,
    IN struct _PARTENTRY* PartEntry)
{
    PFILE_SYSTEM CurrentFileSystem;
    PWSTR FileSystemName = NULL;
#if 0 // For code temporarily disabled below
    NTSTATUS Status;
    WCHAR FsRecFileSystemName[MAX_PATH];
#endif

    CurrentFileSystem = PartEntry->FileSystem;

    /* We have a file system, return it */
    if (CurrentFileSystem != NULL && CurrentFileSystem->FileSystemName != NULL)
        return CurrentFileSystem;

    DPRINT1("File system not found, try to guess one...\n");

    CurrentFileSystem = NULL;

#if 0 // This is an example of old code...

    if ((PartEntry->PartitionType == PARTITION_FAT_12) ||
        (PartEntry->PartitionType == PARTITION_FAT_16) ||
        (PartEntry->PartitionType == PARTITION_HUGE) ||
        (PartEntry->PartitionType == PARTITION_XINT13) ||
        (PartEntry->PartitionType == PARTITION_FAT32) ||
        (PartEntry->PartitionType == PARTITION_FAT32_XINT13))
    {
        if (CheckFatFormat())
            FileSystemName = L"FAT";
        else
            FileSystemName = NULL;
    }
    else if (PartEntry->PartitionType == PARTITION_EXT2)
    {
        if (CheckExt2Format())
            FileSystemName = L"EXT2";
        else
            FileSystemName = NULL;
    }
    else if (PartEntry->PartitionType == PARTITION_IFS)
    {
        if (CheckNtfsFormat())
            FileSystemName = L"NTFS";
        else if (CheckHpfsFormat())
            FileSystemName = L"HPFS";
        else
            FileSystemName = NULL;
    }
    else
    {
        FileSystemName = NULL;
    }

#endif

#if 0 // FIXME: To be fully enabled when our storage stack & al. work better!

    /*
     * We don't have one...
     *
     * Try to infer one using NT file system recognition.
     */
    Status = _MyGetFileSystem(PartEntry, FsRecFileSystemName, ARRAYSIZE(FsRecFileSystemName));
    if (NT_SUCCESS(Status) && *FsRecFileSystemName)
    {
        /* Temporary HACK: map FAT32 back to FAT */
        if (wcscmp(FsRecFileSystemName, L"FAT32") == 0)
            wcscpy(FsRecFileSystemName, L"FAT");

        FileSystemName = FsRecFileSystemName;
        goto Quit;
    }

#endif

    /*
     * We don't have one...
     *
     * Try to infer a preferred file system for this partition, given its ID.
     *
     * WARNING: This is partly a hack, since partitions with the same ID can
     * be formatted with different file systems: for example, usual Linux
     * partitions that are formatted in EXT2/3/4, ReiserFS, etc... have the
     * same partition ID 0x83.
     *
     * The proper fix is to make a function that detects the existing FS
     * from a given partition (not based on the partition ID).
     * On the contrary, for unformatted partitions with a given ID, the
     * following code is OK.
     */
    if ((PartEntry->PartitionType == PARTITION_FAT_12) ||
        (PartEntry->PartitionType == PARTITION_FAT_16) ||
        (PartEntry->PartitionType == PARTITION_HUGE  ) ||
        (PartEntry->PartitionType == PARTITION_XINT13) ||
        (PartEntry->PartitionType == PARTITION_FAT32 ) ||
        (PartEntry->PartitionType == PARTITION_FAT32_XINT13))
    {
        FileSystemName = L"FAT";
    }
    else if (PartEntry->PartitionType == PARTITION_LINUX)
    {
        // WARNING: See the warning above.
        FileSystemName = L"BTRFS";
    }
    else if (PartEntry->PartitionType == PARTITION_IFS)
    {
        // WARNING: See the warning above.
        FileSystemName = L"NTFS"; /* FIXME: Not quite correct! */
        // FIXME: We may have HPFS too...
    }

#if 0
Quit: // For code temporarily disabled above
#endif

    // HACK: WARNING: We cannot write on this FS yet!
    if (FileSystemName)
    {
        if (PartEntry->PartitionType == PARTITION_IFS)
            DPRINT1("Recognized file system %S that doesn't support write support yet!\n", FileSystemName);
    }

    DPRINT1("GetFileSystem -- PartitionType: 0x%02X ; FileSystemName (guessed): %S\n",
            PartEntry->PartitionType, FileSystemName ? FileSystemName : L"None");

    if (FileSystemName != NULL)
        CurrentFileSystem = GetFileSystemByName(FileSystemName);

    return CurrentFileSystem;
}


//
// Formatting routines
//

BOOLEAN
PreparePartitionForFormatting(
    IN struct _PARTENTRY* PartEntry,
    IN PFILE_SYSTEM FileSystem)
{
    if (!FileSystem)
    {
        DPRINT1("No file system specified?\n");
        return FALSE;
    }

    if (wcscmp(FileSystem->FileSystemName, L"FAT") == 0)
    {
        if (PartEntry->SectorCount.QuadPart < 8192)
        {
            /* FAT12 CHS partition (disk is smaller than 4.1MB) */
            SetPartitionType(PartEntry, PARTITION_FAT_12);
        }
        else if (PartEntry->StartSector.QuadPart < 1450560)
        {
            /* Partition starts below the 8.4GB boundary ==> CHS partition */

            if (PartEntry->SectorCount.QuadPart < 65536)
            {
                /* FAT16 CHS partition (partition size < 32MB) */
                SetPartitionType(PartEntry, PARTITION_FAT_16);
            }
            else if (PartEntry->SectorCount.QuadPart < 1048576)
            {
                /* FAT16 CHS partition (partition size < 512MB) */
                SetPartitionType(PartEntry, PARTITION_HUGE);
            }
            else
            {
                /* FAT32 CHS partition (partition size >= 512MB) */
                SetPartitionType(PartEntry, PARTITION_FAT32);
            }
        }
        else
        {
            /* Partition starts above the 8.4GB boundary ==> LBA partition */

            if (PartEntry->SectorCount.QuadPart < 1048576)
            {
                /* FAT16 LBA partition (partition size < 512MB) */
                SetPartitionType(PartEntry, PARTITION_XINT13);
            }
            else
            {
                /* FAT32 LBA partition (partition size >= 512MB) */
                SetPartitionType(PartEntry, PARTITION_FAT32_XINT13);
            }
        }
    }
    else if (wcscmp(FileSystem->FileSystemName, L"BTRFS") == 0)
    {
        SetPartitionType(PartEntry, PARTITION_LINUX);
    }
#if 0
    else if (wcscmp(FileSystem->FileSystemName, L"EXT2") == 0)
    {
        SetPartitionType(PartEntry, PARTITION_EXT2);
    }
    else if (wcscmp(FileSystem->FileSystemName, L"NTFS") == 0)
    {
        SetPartitionType(PartEntry, PARTITION_IFS);
    }
#endif
    else
    {
        /* Unknown file system? */
        DPRINT1("Unknown file system \"%S\"?\n", FileSystem->FileSystemName);
        return FALSE;
    }

//
// FIXME: Do this now, or after the partition was actually formatted??
//
    /* Set the new partition's file system proper */
    PartEntry->FormatState = Formatted; // Well... This may be set after the real formatting takes place (in which case we should change the FormatState to another value)
    PartEntry->FileSystem  = FileSystem;

    return TRUE;
}

/* EOF */