////////////////////////////////////////////////////////////////////////////////
// file : replace.C
//
// string replacement utility
//
// Author         Date       Description
// ------         ----       -----------
// S. Johnson     2/22/97    Creation
//
////////////////////////////////////////////////////////////////////////////////

#include <stdio.h>
#include <fstream.h>
#include <stdlib.h>
#include <string.h>

int
  bIgnore_Case     = 0,
  bVerbose         = 0,
  iOriginal_Length = 0,
  iNew_Length      = 0;

////////////////////////////////////////////////////////////////////////////////
void
fnUsage()
{
  cout  << "Usage: replace [options] 'original string' 'new string' file <files...> \n"
        << "Options:\n"
        << "  -i      ignore case\n"
        << "  -v      verbose\n"
        << "Example: replace 'iNumber' 'iCount' *.C\n";
  exit(1);
} // end fnUsage()

////////////////////////////////////////////////////////////////////////////////
void
fnReplace(char *pchFilename, char *pchOriginal_String, char *pchNew_String)
{
  { // begin local
    ifstream
      ifsInput(pchFilename);
    if (!ifsInput) return;
    ofstream
      ofsOutput("___temp_file___");
    char
      szLine_Buffer[4096];
    int
      iFound = 0;
    while (ifsInput.getline(szLine_Buffer, sizeof(szLine_Buffer))) {
      char
	*pchPosition = szLine_Buffer,
	*pchCurrent  = szLine_Buffer;
      while ((pchPosition = strstr(pchPosition, pchOriginal_String)) != 0) {
	iFound++;
	// write leading up to replacement string
	while (pchPosition != pchCurrent) {
	  ofsOutput << *pchCurrent;
	  pchCurrent++;
	} // end while
	// write new data
	ofsOutput << pchNew_String;
	// adjust position
	pchCurrent = pchPosition += iOriginal_Length;
	if (!(*pchCurrent)) break;
      } // end while
      ofsOutput << pchCurrent << '\n';
    } // end while
    if (bVerbose) cout << "Replaced " << iFound << " occurances in file " << pchFilename << endl;
  } // end local
  rename("___temp_file___", pchFilename);
} // end fnReplace();

////////////////////////////////////////////////////////////////////////////////
void
main(int argc, char *argv[])
{
  if (argc < 4) fnUsage();

  // cycle through arguments		
  int
    iIndex = 1;
  for (; iIndex < argc; iIndex++) {
    // options
    if (argv[iIndex][0] == '-') {
      switch (argv[iIndex][1]) {
        case 'i' :
	  bIgnore_Case++;
	  break;
        case 'v' :
	  bVerbose++;
	  break;
        default :
	  fnUsage();
      } // end switch
    } // end if
    else break;
  } // end for
  // make sure there are enough parameters
  if ((argc -3) < iIndex) fnUsage();

  // store string info
  char
    *pchOriginal_String = argv[iIndex++],
    *pchNew_String      = argv[iIndex++];
  iOriginal_Length = strlen(pchOriginal_String);
  iNew_Length      = strlen(pchNew_String);

  while (iIndex < argc) fnReplace(argv[iIndex++], pchOriginal_String, pchNew_String);
  
} // end main