/*
 *  ReactOS kernel
 *  Copyright (C) 2003 ReactOS Team
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 */
/*
 * COPYRIGHT:       See COPYING in the top level directory
 * PROJECT:         ReactOS system libraries
 * PURPOSE:         Computer name functions
 * FILE:            lib/kernel32/misc/computername.c
 * PROGRAMER:       Eric Kohl
 */

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

#include <k32.h>

#define NDEBUG
#include <debug.h>


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

static
BOOL
GetComputerNameFromRegistry(LPWSTR RegistryKey,
                            LPWSTR ValueNameStr,
                            LPWSTR lpBuffer,
                            LPDWORD nSize)
{
    PKEY_VALUE_PARTIAL_INFORMATION KeyInfo;
    OBJECT_ATTRIBUTES ObjectAttributes;
    UNICODE_STRING KeyName;
    UNICODE_STRING ValueName;
    HANDLE KeyHandle;
    ULONG KeyInfoSize;
    ULONG ReturnSize;
    NTSTATUS Status;

    RtlInitUnicodeString(&KeyName, RegistryKey);
    InitializeObjectAttributes(&ObjectAttributes,
                               &KeyName,
                               OBJ_CASE_INSENSITIVE,
                               NULL,
                               NULL);

    Status = ZwOpenKey(&KeyHandle,
                       KEY_READ,
                       &ObjectAttributes);
    if (!NT_SUCCESS(Status))
    {
        BaseSetLastNTError (Status);
        return FALSE;
    }

    KeyInfoSize = sizeof(KEY_VALUE_PARTIAL_INFORMATION) + *nSize * sizeof(WCHAR);
    KeyInfo = RtlAllocateHeap(RtlGetProcessHeap(), 0, KeyInfoSize);
    if (KeyInfo == NULL)
    {
        ZwClose(KeyHandle);
        SetLastError(ERROR_OUTOFMEMORY);
        return FALSE;
    }

    RtlInitUnicodeString(&ValueName, ValueNameStr);

    Status = ZwQueryValueKey(KeyHandle,
                             &ValueName,
                             KeyValuePartialInformation,
                             KeyInfo,
                             KeyInfoSize,
                             &ReturnSize);

    ZwClose(KeyHandle);

    if (!NT_SUCCESS(Status))
    {
        *nSize = ReturnSize;
        goto failed;
    }

    if (KeyInfo->Type != REG_SZ)
    {
        Status = STATUS_UNSUCCESSFUL;
        goto failed;
    }

    if (!lpBuffer || *nSize < (KeyInfo->DataLength / sizeof(WCHAR)))
    {
        *nSize = ReturnSize;
        Status = STATUS_BUFFER_OVERFLOW;
        goto failed;
    }

    *nSize = KeyInfo->DataLength / sizeof(WCHAR) - 1;
    RtlCopyMemory(lpBuffer, KeyInfo->Data, KeyInfo->DataLength);
    lpBuffer[*nSize] = 0;

    RtlFreeHeap(RtlGetProcessHeap(), 0, KeyInfo);

    return TRUE;

failed:
    RtlFreeHeap(RtlGetProcessHeap(), 0, KeyInfo);
    BaseSetLastNTError(Status);
    return FALSE;
}

/*
 * @implemented
 */
BOOL
WINAPI
GetComputerNameExW(COMPUTER_NAME_FORMAT NameType,
                   LPWSTR lpBuffer,
                   LPDWORD nSize)
{
    UNICODE_STRING ResultString;
    UNICODE_STRING DomainPart;
    RTL_QUERY_REGISTRY_TABLE QueryTable[2];
    NTSTATUS Status;
    BOOL ret = TRUE;
    DWORD HostSize;

    switch (NameType)
    {
        case ComputerNameNetBIOS:
            return GetComputerNameFromRegistry(L"\\Registry\\Machine\\System\\CurrentControlSet"
                                               L"\\Control\\ComputerName\\ComputerName",
                                               L"ComputerName",
                                               lpBuffer,
                                               nSize);

        case ComputerNameDnsDomain:
            return GetComputerNameFromRegistry(L"\\Registry\\Machine\\System\\CurrentControlSet"
                                               L"\\Services\\Tcpip\\Parameters",
                                               L"Domain",
                                               lpBuffer,
                                               nSize);

        case ComputerNameDnsFullyQualified:
            ResultString.Length = 0;
            ResultString.MaximumLength = (USHORT)*nSize * sizeof(WCHAR);
            ResultString.Buffer = lpBuffer;

            RtlZeroMemory(QueryTable, sizeof(QueryTable));
            RtlInitUnicodeString(&DomainPart, NULL);

            QueryTable[0].Name = L"HostName";
            QueryTable[0].Flags = RTL_QUERY_REGISTRY_DIRECT;
            QueryTable[0].EntryContext = &DomainPart;

            Status = RtlQueryRegistryValues(RTL_REGISTRY_ABSOLUTE,
                                            L"\\Registry\\Machine\\System"
                                            L"\\CurrentControlSet\\Services\\Tcpip"
                                            L"\\Parameters",
                                            QueryTable,
                                            NULL,
                                            NULL);

            if (NT_SUCCESS(Status))
            {
                Status = RtlAppendUnicodeStringToString(&ResultString, &DomainPart);
                HostSize = DomainPart.Length;

                if (!NT_SUCCESS(Status))
                {
                    ret = FALSE;
                }

                RtlAppendUnicodeToString(&ResultString, L".");
                RtlFreeUnicodeString(&DomainPart);

                RtlInitUnicodeString(&DomainPart, NULL);
                QueryTable[0].Name = L"Domain";
                QueryTable[0].Flags = RTL_QUERY_REGISTRY_DIRECT;
                QueryTable[0].EntryContext = &DomainPart;

                Status = RtlQueryRegistryValues(RTL_REGISTRY_ABSOLUTE,
                                                L"\\Registry\\Machine\\System"
                                                L"\\CurrentControlSet\\Services\\Tcpip"
                                                L"\\Parameters",
                                                QueryTable,
                                                NULL,
                                                NULL);

                if (NT_SUCCESS(Status))
                {
                    Status = RtlAppendUnicodeStringToString(&ResultString, &DomainPart);
                    if ((!NT_SUCCESS(Status)) || (!ret))
                    {
                        *nSize = HostSize + DomainPart.Length;
                        SetLastError(ERROR_MORE_DATA);
                        RtlFreeUnicodeString(&DomainPart);
                        return FALSE;
                    }
                    RtlFreeUnicodeString(&DomainPart);
                    *nSize = ResultString.Length / sizeof(WCHAR) - 1;
                    return TRUE;
                }
            }
            return FALSE;

        case ComputerNameDnsHostname:
            return GetComputerNameFromRegistry(L"\\Registry\\Machine\\System\\CurrentControlSet"
                                               L"\\Services\\Tcpip\\Parameters",
                                               L"Hostname",
                                               lpBuffer,
                                               nSize);

        case ComputerNamePhysicalDnsDomain:
            return GetComputerNameFromRegistry(L"\\Registry\\Machine\\System\\CurrentControlSet"
                                               L"\\Services\\Tcpip\\Parameters",
                                               L"Domain",
                                               lpBuffer,
                                               nSize);

        /* XXX Redo these */
        case ComputerNamePhysicalDnsFullyQualified:
            return GetComputerNameExW(ComputerNameDnsFullyQualified,
                                      lpBuffer,
                                      nSize);

        case ComputerNamePhysicalDnsHostname:
            return GetComputerNameExW(ComputerNameDnsHostname,
                                      lpBuffer,
                                      nSize);

        case ComputerNamePhysicalNetBIOS:
            return GetComputerNameExW(ComputerNameNetBIOS,
                                      lpBuffer,
                                      nSize);

        case ComputerNameMax:
            return FALSE;
    }

    return FALSE;
}

/*
 * @implemented
 */
BOOL
WINAPI
GetComputerNameExA(COMPUTER_NAME_FORMAT NameType,
                   LPSTR lpBuffer,
                   LPDWORD nSize)
{
    UNICODE_STRING UnicodeString;
    ANSI_STRING AnsiString;
    BOOL Result;
    PWCHAR TempBuffer = RtlAllocateHeap( RtlGetProcessHeap(), 0, *nSize * sizeof(WCHAR) );

    if (!TempBuffer)
    {
        SetLastError(ERROR_NOT_ENOUGH_MEMORY);
        return FALSE;
    }

    AnsiString.MaximumLength = (USHORT)*nSize;
    AnsiString.Length = 0;
    AnsiString.Buffer = lpBuffer;

    Result = GetComputerNameExW(NameType, TempBuffer, nSize);

    if (Result)
    {
        UnicodeString.MaximumLength = (USHORT)*nSize * sizeof(WCHAR) + sizeof(WCHAR);
        UnicodeString.Length = (USHORT)*nSize * sizeof(WCHAR) + sizeof(WCHAR);
        UnicodeString.Buffer = TempBuffer;

        RtlUnicodeStringToAnsiString(&AnsiString,
                                     &UnicodeString,
                                     FALSE);
    }

    RtlFreeHeap(RtlGetProcessHeap(), 0, TempBuffer);

    return Result;
}

/*
 * @implemented
 */
BOOL
WINAPI
GetComputerNameA(LPSTR lpBuffer, LPDWORD lpnSize)
{
    BOOL ret;
    ret = GetComputerNameExA(ComputerNameNetBIOS, lpBuffer, lpnSize);    
    if(!ret && GetLastError() == ERROR_MORE_DATA)
      SetLastError(ERROR_BUFFER_OVERFLOW);
      return ret;
}


/*
 * @implemented
 */
BOOL
WINAPI
GetComputerNameW(LPWSTR lpBuffer, LPDWORD lpnSize)
{
    BOOL ret;
    ret=GetComputerNameExW(ComputerNameNetBIOS, lpBuffer, lpnSize);
    if(!ret && GetLastError() == ERROR_MORE_DATA)
      SetLastError(ERROR_BUFFER_OVERFLOW);
    return ret;
}


/*
 * @implemented
 */
static
BOOL
IsValidComputerName(COMPUTER_NAME_FORMAT NameType,
                    LPCWSTR lpComputerName)
{
    PWCHAR p;
    ULONG Length;

    /* FIXME: do verification according to NameType */

    Length = 0;
    p = (PWCHAR)lpComputerName;

    while (*p != 0)
    {
        if (!(iswctype(*p, _ALPHA | _DIGIT) || *p == L'!' || *p == L'@' || *p == L'#' ||
            *p == L'$' || *p == L'%' || *p == L'^' || *p == L'&' || *p == L'\'' ||
            *p == L')' || *p == L'(' || *p == L'.' || *p == L'-' || *p == L'_' ||
            *p == L'{' || *p == L'}' || *p == L'~'))
            return FALSE;

        Length++;
        p++;
    }

    if (Length == 0 || Length > MAX_COMPUTERNAME_LENGTH)
        return FALSE;

    return TRUE;
}


static
BOOL
SetComputerNameToRegistry(LPCWSTR RegistryKey,
                          LPCWSTR ValueNameStr,
                          LPCWSTR lpBuffer)
{
    OBJECT_ATTRIBUTES ObjectAttributes;
    UNICODE_STRING KeyName;
    UNICODE_STRING ValueName;
    HANDLE KeyHandle;
    NTSTATUS Status;

    RtlInitUnicodeString(&KeyName, RegistryKey);
    InitializeObjectAttributes(&ObjectAttributes,
                               &KeyName,
                               OBJ_CASE_INSENSITIVE,
                               NULL,
                               NULL);

    Status = NtOpenKey(&KeyHandle,
                       KEY_WRITE,
                       &ObjectAttributes);
    if (!NT_SUCCESS(Status))
    {
        BaseSetLastNTError(Status);
        return FALSE;
    }

    RtlInitUnicodeString(&ValueName, ValueNameStr);

    Status = NtSetValueKey(KeyHandle,
                           &ValueName,
                           0,
                           REG_SZ,
                           (PVOID)lpBuffer,
                           (wcslen (lpBuffer) + 1) * sizeof(WCHAR));
    if (!NT_SUCCESS(Status))
    {
        ZwClose(KeyHandle);
        BaseSetLastNTError(Status);
        return FALSE;
    }

    NtFlushKey(KeyHandle);
    ZwClose(KeyHandle);

    return TRUE;
}


/*
 * @implemented
 */
BOOL
WINAPI
SetComputerNameA(LPCSTR lpComputerName)
{
    return SetComputerNameExA(ComputerNamePhysicalNetBIOS, lpComputerName);
}


/*
 * @implemented
 */
BOOL
WINAPI
SetComputerNameW(LPCWSTR lpComputerName)
{
    return SetComputerNameExW(ComputerNamePhysicalNetBIOS, lpComputerName);
}


/*
 * @implemented
 */
BOOL
WINAPI
SetComputerNameExA(COMPUTER_NAME_FORMAT NameType,
                   LPCSTR lpBuffer)
{
    UNICODE_STRING Buffer;
    BOOL bResult;

    RtlCreateUnicodeStringFromAsciiz(&Buffer, (LPSTR)lpBuffer);

    bResult = SetComputerNameExW(NameType, Buffer.Buffer);

    RtlFreeUnicodeString(&Buffer);

    return bResult;
}


/*
 * @implemented
 */
BOOL
WINAPI
SetComputerNameExW(COMPUTER_NAME_FORMAT NameType,
                   LPCWSTR lpBuffer)
{
    if (!IsValidComputerName(NameType, lpBuffer))
    {
        SetLastError(ERROR_INVALID_PARAMETER);
        return FALSE;
    }

    switch( NameType )
    {
        case ComputerNamePhysicalDnsDomain:
            return SetComputerNameToRegistry(L"\\Registry\\Machine\\System\\CurrentControlSet"
                                             L"\\Services\\Tcpip\\Parameters",
                                             L"Domain",
                                             lpBuffer);

        case ComputerNamePhysicalDnsHostname:
            return SetComputerNameToRegistry(L"\\Registry\\Machine\\System\\CurrentControlSet"
                                             L"\\Services\\Tcpip\\Parameters",
                                             L"Hostname",
                                             lpBuffer);

        case ComputerNamePhysicalNetBIOS:
            return SetComputerNameToRegistry(L"\\Registry\\Machine\\System\\CurrentControlSet"
                                             L"\\Control\\ComputerName\\ComputerName",
                                             L"ComputerName",
                                             lpBuffer);

        default:
            SetLastError (ERROR_INVALID_PARAMETER);
            return FALSE;
    }
}


/*
 * @implemented
 */
BOOL
WINAPI
DnsHostnameToComputerNameA(LPCSTR Hostname,
                           LPSTR ComputerName,
                           LPDWORD nSize)
{
    DWORD len;

    DPRINT("(%s, %p, %p)\n", Hostname, ComputerName, nSize);

    if (!Hostname || !nSize)
        return FALSE;

    len = lstrlenA(Hostname);

    if (len > MAX_COMPUTERNAME_LENGTH)
        len = MAX_COMPUTERNAME_LENGTH;

    if (*nSize < len)
    {
        *nSize = len;
        return FALSE;
    }

    if (!ComputerName) return FALSE;

    memcpy(ComputerName, Hostname, len);
    ComputerName[len + 1] = 0;
    return TRUE;
}


/*
 * @implemented
 */
BOOL
WINAPI
DnsHostnameToComputerNameW(LPCWSTR hostname,
                           LPWSTR computername,
                           LPDWORD size)
{
    DWORD len;

    DPRINT("(%s, %p, %p): stub\n", hostname, computername, size);

    if (!hostname || !size) return FALSE;
    len = lstrlenW(hostname);

    if (len > MAX_COMPUTERNAME_LENGTH)
        len = MAX_COMPUTERNAME_LENGTH;

    if (*size < len)
    {
        *size = len;
        return FALSE;
    }
    if (!computername) return FALSE;

    memcpy(computername, hostname, len * sizeof(WCHAR));
    computername[len + 1] = 0;
    return TRUE;
}

DWORD
WINAPI
AddLocalAlternateComputerNameA(LPSTR lpName, PNTSTATUS Status)
{
    STUB;
    return 0;
}

DWORD
WINAPI
AddLocalAlternateComputerNameW(LPWSTR lpName, PNTSTATUS Status)
{
    STUB;
    return 0;
}

DWORD
WINAPI
EnumerateLocalComputerNamesA(PVOID pUnknown, DWORD Size, LPSTR lpBuffer, LPDWORD lpnSize)
{
    STUB;
    return ERROR_CALL_NOT_IMPLEMENTED;
}

DWORD
WINAPI
EnumerateLocalComputerNamesW(PVOID pUnknown, DWORD Size, LPWSTR lpBuffer, LPDWORD lpnSize)
{
    STUB;
    return ERROR_CALL_NOT_IMPLEMENTED;
}

DWORD
WINAPI
RemoveLocalAlternateComputerNameA(LPSTR lpName, DWORD Unknown)
{
    STUB;
    return ERROR_CALL_NOT_IMPLEMENTED;
}

DWORD
WINAPI
RemoveLocalAlternateComputerNameW(LPWSTR lpName, DWORD Unknown)
{
    STUB;
    return ERROR_CALL_NOT_IMPLEMENTED;
}

/*
 * @unimplemented
 */
BOOL
WINAPI
SetLocalPrimaryComputerNameA(IN DWORD Unknown1,
                             IN DWORD Unknown2)
{
    STUB;
    return FALSE;
}

/*
 * @unimplemented
 */
BOOL
WINAPI
SetLocalPrimaryComputerNameW(IN DWORD Unknown1,
                             IN DWORD Unknown2)
{
    STUB;
    return FALSE;
}


/* EOF */
