// Windows/FileIO.cpp

#include "StdAfx.h"

#include "FileIO.h"
#include "Defs.h"
#ifdef WIN_LONG_PATH
#include "../Common/MyString.h"
#endif
#ifndef _UNICODE
#include "../Common/StringConvert.h"
#endif

#ifndef _UNICODE
extern bool g_IsNT;
#endif

namespace NWindows {
namespace NFile {

#if defined(WIN_LONG_PATH) && defined(_UNICODE)
#define WIN_LONG_PATH2
#endif

#ifdef WIN_LONG_PATH
bool GetLongPathBase(LPCWSTR s, UString &res)
{
  res.Empty();
  int len = MyStringLen(s);
  wchar_t c = s[0];
  if (len < 1 || c == L'\\' || c == L'.' && (len == 1 || len == 2 && s[1] == L'.'))
    return true;
  UString curDir;
  bool isAbs = false;
  if (len > 3)
    isAbs = (s[1] == L':' && s[2] == L'\\' && (c >= L'a' && c <= L'z' || c >= L'A' && c <= L'Z'));

  if (!isAbs)
    {
      DWORD needLength = ::GetCurrentDirectoryW(MAX_PATH + 1, curDir.GetBuffer(MAX_PATH + 1));
      curDir.ReleaseBuffer();
      if (needLength == 0 || needLength > MAX_PATH)
        return false;
      if (curDir[curDir.Length() - 1] != L'\\')
        curDir += L'\\';
    }
  res = UString(L"\\\\?\\") + curDir + s;
  return true;
}

bool GetLongPath(LPCWSTR path, UString &longPath)
{
  if (GetLongPathBase(path, longPath))
    return !longPath.IsEmpty();
  return false;
}
#endif

namespace NIO {

CFileBase::~CFileBase() { Close(); }

bool CFileBase::Create(LPCTSTR fileName, DWORD desiredAccess,
    DWORD shareMode, DWORD creationDisposition, DWORD flagsAndAttributes)
{
  if (!Close())
    return false;
  _handle = ::CreateFile(fileName, desiredAccess, shareMode,
      (LPSECURITY_ATTRIBUTES)NULL, creationDisposition,
      flagsAndAttributes, (HANDLE)NULL);
  #ifdef WIN_LONG_PATH2
  if (_handle == INVALID_HANDLE_VALUE)
  {
    UString longPath;
    if (GetLongPath(fileName, longPath))
      _handle = ::CreateFileW(longPath, desiredAccess, shareMode,
        (LPSECURITY_ATTRIBUTES)NULL, creationDisposition,
        flagsAndAttributes, (HANDLE)NULL);
  }
  #endif
  return (_handle != INVALID_HANDLE_VALUE);
}

#ifndef _UNICODE
bool CFileBase::Create(LPCWSTR fileName, DWORD desiredAccess,
    DWORD shareMode, DWORD creationDisposition, DWORD flagsAndAttributes)
{
  if (!g_IsNT)
    return Create(UnicodeStringToMultiByte(fileName, ::AreFileApisANSI() ? CP_ACP : CP_OEMCP),
      desiredAccess, shareMode, creationDisposition, flagsAndAttributes);
  if (!Close())
    return false;
  _handle = ::CreateFileW(fileName, desiredAccess, shareMode,
    (LPSECURITY_ATTRIBUTES)NULL, creationDisposition,
    flagsAndAttributes, (HANDLE)NULL);
  #ifdef WIN_LONG_PATH
  if (_handle == INVALID_HANDLE_VALUE)
  {
    UString longPath;
    if (GetLongPath(fileName, longPath))
      _handle = ::CreateFileW(longPath, desiredAccess, shareMode,
        (LPSECURITY_ATTRIBUTES)NULL, creationDisposition,
        flagsAndAttributes, (HANDLE)NULL);
  }
  #endif
  return (_handle != INVALID_HANDLE_VALUE);
}
#endif

bool CFileBase::Close()
{
  if (_handle == INVALID_HANDLE_VALUE)
    return true;
  if (!::CloseHandle(_handle))
    return false;
  _handle = INVALID_HANDLE_VALUE;
  return true;
}

bool CFileBase::GetPosition(UInt64 &position) const
{
  return Seek(0, FILE_CURRENT, position);
}

bool CFileBase::GetLength(UInt64 &length) const
{
  DWORD sizeHigh;
  DWORD sizeLow = ::GetFileSize(_handle, &sizeHigh);
  if (sizeLow == 0xFFFFFFFF)
    if (::GetLastError() != NO_ERROR)
      return false;
  length = (((UInt64)sizeHigh) << 32) + sizeLow;
  return true;
}

bool CFileBase::Seek(Int64 distanceToMove, DWORD moveMethod, UInt64 &newPosition) const
{
  LARGE_INTEGER value;
  value.QuadPart = distanceToMove;
  value.LowPart = ::SetFilePointer(_handle, value.LowPart, &value.HighPart, moveMethod);
  if (value.LowPart == 0xFFFFFFFF)
    if (::GetLastError() != NO_ERROR)
      return false;
  newPosition = value.QuadPart;
  return true;
}

bool CFileBase::Seek(UInt64 position, UInt64 &newPosition)
{
  return Seek(position, FILE_BEGIN, newPosition);
}

bool CFileBase::SeekToBegin()
{
  UInt64 newPosition;
  return Seek(0, newPosition);
}

bool CFileBase::SeekToEnd(UInt64 &newPosition)
{
  return Seek(0, FILE_END, newPosition);
}

bool CFileBase::GetFileInformation(CByHandleFileInfo &fileInfo) const
{
  BY_HANDLE_FILE_INFORMATION winFileInfo;
  if (!::GetFileInformationByHandle(_handle, &winFileInfo))
    return false;
  fileInfo.Attributes = winFileInfo.dwFileAttributes;
  fileInfo.CTime = winFileInfo.ftCreationTime;
  fileInfo.ATime = winFileInfo.ftLastAccessTime;
  fileInfo.MTime = winFileInfo.ftLastWriteTime;
  fileInfo.VolumeSerialNumber = winFileInfo.dwFileAttributes;
  fileInfo.Size = (((UInt64)winFileInfo.nFileSizeHigh) << 32) +  winFileInfo.nFileSizeLow;
  fileInfo.NumberOfLinks = winFileInfo.nNumberOfLinks;
  fileInfo.FileIndex = (((UInt64)winFileInfo.nFileIndexHigh) << 32) + winFileInfo.nFileIndexLow;
  return true;
}

/////////////////////////
// CInFile

bool CInFile::Open(LPCTSTR fileName, DWORD shareMode, DWORD creationDisposition, DWORD flagsAndAttributes)
  { return Create(fileName, GENERIC_READ, shareMode, creationDisposition, flagsAndAttributes); }

bool CInFile::OpenShared(LPCTSTR fileName, bool shareForWrite)
{ return Open(fileName, FILE_SHARE_READ | (shareForWrite ? FILE_SHARE_WRITE : 0), OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL); }

bool CInFile::Open(LPCTSTR fileName)
  { return OpenShared(fileName, false); }

#ifndef _UNICODE
bool CInFile::Open(LPCWSTR fileName, DWORD shareMode, DWORD creationDisposition, DWORD flagsAndAttributes)
  { return Create(fileName, GENERIC_READ, shareMode, creationDisposition, flagsAndAttributes); }

bool CInFile::OpenShared(LPCWSTR fileName, bool shareForWrite)
{ return Open(fileName, FILE_SHARE_READ | (shareForWrite ? FILE_SHARE_WRITE : 0), OPEN_EXISTING, FILE_ATTRIBUTE_NORMAL); }

bool CInFile::Open(LPCWSTR fileName)
  { return OpenShared(fileName, false); }
#endif

// ReadFile and WriteFile functions in Windows have BUG:
// If you Read or Write 64MB or more (probably min_failure_size = 64MB - 32KB + 1)
// from/to Network file, it returns ERROR_NO_SYSTEM_RESOURCES
// (Insufficient system resources exist to complete the requested service).

// Probably in some version of Windows there are problems with other sizes:
// for 32 MB (maybe also for 16 MB).
// And message can be "Network connection was lost"

static UInt32 kChunkSizeMax = (1 << 22);

bool CInFile::ReadPart(void *data, UInt32 size, UInt32 &processedSize)
{
  if (size > kChunkSizeMax)
    size = kChunkSizeMax;
  DWORD processedLoc = 0;
  bool res = BOOLToBool(::ReadFile(_handle, data, size, &processedLoc, NULL));
  processedSize = (UInt32)processedLoc;
  return res;
}

bool CInFile::Read(void *data, UInt32 size, UInt32 &processedSize)
{
  processedSize = 0;
  do
  {
    UInt32 processedLoc = 0;
    bool res = ReadPart(data, size, processedLoc);
    processedSize += processedLoc;
    if (!res)
      return false;
    if (processedLoc == 0)
      return true;
    data = (void *)((unsigned char *)data + processedLoc);
    size -= processedLoc;
  }
  while (size > 0);
  return true;
}

/////////////////////////
// COutFile

bool COutFile::Open(LPCTSTR fileName, DWORD shareMode, DWORD creationDisposition, DWORD flagsAndAttributes)
  { return CFileBase::Create(fileName, GENERIC_WRITE, shareMode, creationDisposition, flagsAndAttributes); }

static inline DWORD GetCreationDisposition(bool createAlways)
  { return createAlways? CREATE_ALWAYS: CREATE_NEW; }

bool COutFile::Open(LPCTSTR fileName, DWORD creationDisposition)
  { return Open(fileName, FILE_SHARE_READ, creationDisposition, FILE_ATTRIBUTE_NORMAL); }

bool COutFile::Create(LPCTSTR fileName, bool createAlways)
  { return Open(fileName, GetCreationDisposition(createAlways)); }

#ifndef _UNICODE

bool COutFile::Open(LPCWSTR fileName, DWORD shareMode, DWORD creationDisposition, DWORD flagsAndAttributes)
  { return CFileBase::Create(fileName, GENERIC_WRITE, shareMode,      creationDisposition, flagsAndAttributes); }

bool COutFile::Open(LPCWSTR fileName, DWORD creationDisposition)
  { return Open(fileName, FILE_SHARE_READ,  creationDisposition, FILE_ATTRIBUTE_NORMAL); }

bool COutFile::Create(LPCWSTR fileName, bool createAlways)
  { return Open(fileName, GetCreationDisposition(createAlways)); }

#endif

bool COutFile::SetTime(const FILETIME *cTime, const FILETIME *aTime, const FILETIME *mTime)
  { return BOOLToBool(::SetFileTime(_handle, cTime, aTime, mTime)); }

bool COutFile::SetMTime(const FILETIME *mTime) {  return SetTime(NULL, NULL, mTime); }

bool COutFile::WritePart(const void *data, UInt32 size, UInt32 &processedSize)
{
  if (size > kChunkSizeMax)
    size = kChunkSizeMax;
  DWORD processedLoc = 0;
  bool res = BOOLToBool(::WriteFile(_handle, data, size, &processedLoc, NULL));
  processedSize = (UInt32)processedLoc;
  return res;
}

bool COutFile::Write(const void *data, UInt32 size, UInt32 &processedSize)
{
  processedSize = 0;
  do
  {
    UInt32 processedLoc = 0;
    bool res = WritePart(data, size, processedLoc);
    processedSize += processedLoc;
    if (!res)
      return false;
    if (processedLoc == 0)
      return true;
    data = (const void *)((const unsigned char *)data + processedLoc);
    size -= processedLoc;
  }
  while (size > 0);
  return true;
}

bool COutFile::SetEndOfFile() { return BOOLToBool(::SetEndOfFile(_handle)); }

bool COutFile::SetLength(UInt64 length)
{
  UInt64 newPosition;
  if (!Seek(length, newPosition))
    return false;
  if (newPosition != length)
    return false;
  return SetEndOfFile();
}

}}}