/*-- WVFILE.C -- File containing routines to do I/O under Windows.
 */

#include "windows.h"
#include "wvglob.h"
#include "winvn.h"
#ifndef MAC
#include "winundoc.h"
#include <io.h>
#else
#include <unix.h>
#include <fcntl.h>
#endif

#ifdef MAC
extern long int _lread (HANDLE hFile, char *buf, long int bufsize);
extern _llseek (HANDLE hFile, long int offset, int posmode);
#endif


/*--- function MRROpenFile --------------------------------------------
 *
 *  Perform the same function as Windows' OpenFile, but also
 *  create an instance of a structure that keeps track of file-related
 *  information (most importantly, an file buffer so I don't have to
 *  do 1-byte system reads).
 *
 *    Entry    FileName    is the file name of the file to open.
 *             vRef        is the reference number (MAC only)
 *             Mode        is the mode under which to open the file.
 *
 *    Exit     MRRFile     points to a dynamically-allocated structure
 *                         containing info about the file.
 *             Returns a handle to the file; 0 if failure.
 */
HANDLE
MRROpenFile (FileName, vRef, Mode, MRRFile)
     char *FileName;
     int vRef;
     int Mode;
     TypMRRFile **MRRFile;
{
  HANDLE hMyFile, hMRR;
  TypMRRFile *MyMRRFile;
  int retcode;
#ifdef MAC
  int MacMode;
  int myvRef;
  Str255 pFileName;
  int fRefNum;
  OSErr myErr;
#endif

  hMRR = LocalAlloc (LMEM_FIXED, sizeof (TypMRRFile));
  if (!hMRR)
    {
      return (0);
    }
  else
    {
      MyMRRFile = (TypMRRFile *) LocalLock (hMRR);
      MyMRRFile->hthis = hMRR;
      MyMRRFile->bufidx = 0;
      MyMRRFile->bytesread = 0;
      MyMRRFile->eofflag = FALSE;
      MyMRRFile->mode = Mode;

      if (Mode == OF_WRITE)
	{
	  hMyFile = OpenFile (FileName, &(MyMRRFile->of), OF_EXIST);
	  if (hMyFile == -1)
	    Mode = OF_CREATE;
	}
      hMyFile = retcode = OpenFile ((char far *) FileName, &(MyMRRFile->of), Mode);
      if (retcode == (-1))
	{
	  LocalUnlock (hMRR);
	  LocalFree (hMRR);
	  return (0);
	}
      else
	{
	  MyMRRFile->hFile = hMyFile;
	}
    }
  *MRRFile = MyMRRFile;
  return ((HANDLE) hMyFile);
}

/*--- function MRRCloseFile --------------------------------------------
 *
 *  Perform the same function as the close function, but also
 *  deallocate the structure allocated by MRROpenFile.
 *
 *    Entry    MRRFile  points to a structure describing the file.
 */
void
MRRCloseFile (MRRFile)
     TypMRRFile *MRRFile;
{
  HANDLE hMyMRRFile;
  long int nbytes;
  int num_written = 0;

  if (MRRFile->mode == OF_WRITE || MRRFile->mode == OF_CREATE)
    {
// write is not in win32.  What was this doing???
//        write (MRRFile->hFile, MRRFile->buf, MRRFile->bufidx);
	  WriteFile (MRRFile->hFile, MRRFile->buf, MRRFile->bufidx, &num_written, NULL);
	  if (num_written != MRRFile->bufidx)
	    MessageBox (hWndConf, "error in MRRWriteLine, num_written != MRRFile->bufidx", "WinVN", MB_OK && MB_ICONHAND);
    }
#ifdef MAC
  FSClose ((int) MRRFile->hFile);
  FlushVol (NULL, MRRFile->vRef);
#else
//  _lclose (MRRFile->hFile);
// Let's try the win32 function:
  CloseHandle (MRRFile->hFile);
#endif
  hMyMRRFile = MRRFile->hthis;
  LocalUnlock (hMyMRRFile);
  LocalFree (hMyMRRFile);
}

/*--- function MRRReadLine ---------------------------------------------
 *
 *  Read in a line from a file, very much like "fgets".
 *  Lines are assumed to be terminated by CR/LF (except that this
 *  is optional for the last line in a file).
 *
 *  No CR, LF, or zero byte is placed in the user's buffer or
 *  counted as a data byte in the returned count.
 *
 *    Entry    MRRFile  points to a structure describing the file.
 *             Linebuf  is the place to put the line.
 *             Len      is the length of Linebuf.
 *
 *    Exit     Linebuf  contains a line.
 *             Returns number of characters read.  0 means an empty line;
 *              -1 means EOF.
 */
int
MRRReadLine (MRRFile, Linebuf, Len)
     TypMRRFile *MRRFile;
     char *Linebuf;
     int Len;
{
  int BytesReturned = 0;
  char ch;

  /* If we hit the EOF while reading last time, we might not have   */
  /* had to return an EOF indication then--but we certainly do now. */

  if (MRRFile->eofflag)
    return (-1);

  /* Read bytes until we exhaust the user's buffer,                 */
  /* empty our own internal buffer,                                 */
  /* or hit a CR (which hopefully belongs to a CR/LF pair).         */

readlp:;
  while (Len && MRRFile->bufidx < MRRFile->bytesread &&
	 (ch = MRRFile->buf[MRRFile->bufidx]) != '\r' && ch != '\n')
    {
      *(Linebuf++) = ch;
      BytesReturned++;
      (MRRFile->bufidx)++;
      Len--;
    }

  /* If we emptied our own internal buffer, fill 'er up again       */
  /* from the file.  If the read hits EOF, return the user's        */
  /* data now (indicating EOF if we never got any data bytes        */
  /* else go back up and continue taking from the buffer.           */

  if (MRRFile->bufidx >= MRRFile->bytesread)
    {
      MRRFile->bufidx = 0;
      MRRFile->bytesread = _lread (MRRFile->hFile, MRRFile->buf, BUFSIZE);
      if (MRRFile->bytesread > 0)
	{
	  goto readlp;
	}
      else
	{
	  MRRFile->eofflag = TRUE;
	  if (!BytesReturned)
	    BytesReturned--;
	  goto endit;
	}
    }

  /* If we reach here, we either filled the user's buffer or        */
  /* hit a CR.  No EOF was encountered.                             */
  /* Either way, we must now skip to the beginning of the next      */
  /* line.  This means skipping to the next LF.  Since in most      */
  /* cases the user does specify a big enough buffer, in most       */
  /* cases all we are doing here is reading up the next character   */
  /* (assuming it's a LF).                                          */
  /* All data that should go in the user's buffer is there by now.  */

skipLF:;
#ifndef MAC
  while (MRRFile->bufidx < MRRFile->bytesread &&
	 MRRFile->buf[MRRFile->bufidx] != '\n')
    {
      (MRRFile->bufidx)++;
    }
#endif
  /* We either found the LineFeed we were looking for, or hit       */
  /* the end of our internal buffer.  If the latter, fill 'er       */
  /* up and try again.                                              */

  if (MRRFile->bufidx >= MRRFile->bytesread)
    {
      MRRFile->bufidx = 0;
      MRRFile->bytesread = _lread (MRRFile->hFile, MRRFile->buf, BUFSIZE);
      if (MRRFile->bytesread > 0)
	{
	  goto skipLF;
	}
      else
	{
	  MRRFile->eofflag = TRUE;
	  goto endit;
	}
    }

  /* The buffer pointer is now pointing at the LF.  Advance         */
  /* it by one so we'll get the first character of the next         */
  /* line next time.                                                */
  /* If this takes us past the end of the buffer, no problem.       */

#ifndef MAC
  if (MRRFile->buf[MRRFile->bufidx] == '\n')
    (MRRFile->bufidx)++;
#else
  if (MRRFile->buf[MRRFile->bufidx] == '\r')
    (MRRFile->bufidx)++;
#endif

endit:;
  return (BytesReturned);
}

/*--- function MRRWriteLine ---------------------------------------------
 *
 *  Write out a line of text, followed by a CR and LF.
 *
 *    Entry    MRRFile  points to a structure describing the file.
 *             LineBuf  points to line buffer to write out.
 *             Len      is the number of bytes to write.
 */
BOOL
MRRWriteLine (MRRFile, LineBuf, Len)
     TypMRRFile *MRRFile;
     char far *LineBuf;
     int Len;
{
  int BytesToCopy;
  static NotFirst = 0;
  long int nbytes;
  int num_written = 0;

  do
    {
      BytesToCopy = Len < (BUFSIZE - MRRFile->bufidx) ?
	Len : BUFSIZE - MRRFile->bufidx;
      MoveBytes (LineBuf, (char far *) (MRRFile->buf + MRRFile->bufidx), BytesToCopy);
      MRRFile->bufidx += BytesToCopy;
      LineBuf += BytesToCopy;
      Len -= BytesToCopy;
      if (MRRFile->bufidx >= BUFSIZE)
	{
// write is not in win32.  What was this doing???
//	  write (MRRFile->hFile, MRRFile->buf, BUFSIZE);
	  WriteFile (MRRFile->hFile, MRRFile->buf, BUFSIZE, &num_written, NULL);
	  if (num_written != BUFSIZE)
	    MessageBox (hWndConf, "error in MRRWriteLine, num_written != BUFSIZE", "WinVN", MB_OK && MB_ICONHAND);
	  MRRFile->bufidx = 0;
	}
    }
  while (Len > 0);

  if (!(NotFirst++))
    {
#ifndef MAC
      MRRWriteLine (MRRFile, "\r\n", 2);
#else
      MRRWriteLine (MRRFile, "\r\n", 1);
#endif
    }
  NotFirst--;
  return (1);
}

/*-- function MRRWriteDocument -----------------------------------------
 *
 *  Write out an entire document to disk.
 *
 *  Entry   Document    points to a document.
 *          Offset      is the number of bytes to skip at the beginning
 *                      of the line (between the end of the structure
 *                      described in TypLine and the beginning of text).
 *                      In most cases this will be zero.
 *          szFileName  points to the file name to save to.
 *          vRef        points to the directory--used only by Macintosh.
 *          Append      is TRUE iff we should append to the file.
 *
 *    Returns TRUE iff we wrote the file OK.
 */
BOOL
MRRWriteDocument (Document, Offset, szFileName, vRef, Append)
     TypDoc *Document;
     int Offset;
     char *szFileName;
     int vRef;
     BOOL Append;
{
  TypMRRFile *MRRFile;
  HANDLE hFile;
  HANDLE hBlock;
  TypBlock far *BlockPtr;
  TypLine far *LinePtr;
  int mode;

  if (Append)
    {
      mode = OF_WRITE;
    }
  else
    {
      mode = OF_CREATE;
    }
  hFile = MRROpenFile (szFileName, vRef, mode, &MRRFile);
  if (Append)
    {
      _llseek (hFile, 0L, 2);
    }

  if (hFile)
    {
      LockLine (Document->hFirstBlock, sizeof (TypBlock), (TypLineID) 0L, &BlockPtr, &LinePtr);
      while (LinePtr->length != END_OF_BLOCK)
	{
	  MRRWriteLine (MRRFile, ((char far *) LinePtr) + Offset + sizeof (TypLine),
#if 1
	      lstrlen (((char far *) LinePtr) + sizeof (TypLine) + Offset));
#else
		     LinePtr->length - sizeof (TypLine) - sizeof (int) - 1);
#endif
	  NextLine (&BlockPtr, &LinePtr);
	}
      GlobalUnlock (BlockPtr->hCurBlock);
      MRRCloseFile (MRRFile);
    }
  else
    {
      return (0);
    }
  return (TRUE);
}