/*
    HTTrack external callbacks example : changing folder names ending with ".com"
    with ".c0m" as a workaround of IIS bug (see KB 275601)

    How to build: (callback.so or callback.dll)
      With GNU-GCC:
        gcc -O -g3 -Wall -D_REENTRANT -shared -o mycallback.so callbacks-example.c -lhttrack1
      With MS-Visual C++:
        cl -LD -nologo -W3 -Zi -Zp4 -DWIN32 -Fe"mycallback.dll" callbacks-example.c libhttrack1.lib

      Note: the httrack library linker option is only necessary when using libhttrack's functions inside the callback
*/

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

/* Standard httrack module includes */
#include "httrack-library.h"
#include "htsopt.h"
#include "htsdefines.h"

/* Function definitions */
static int mysavename(t_hts_callbackarg *carg, httrackp *opt, const char* adr_complete, const char* fil_complete, const char* referer_adr, const char* referer_fil, char* save);

/* external functions */
EXTERNAL_FUNCTION int hts_plug(httrackp *opt, const char* argv);

/* 
module entry point 
*/
EXTERNAL_FUNCTION int hts_plug(httrackp *opt, const char* argv) {
  const char *arg = strchr(argv, ',');
  if (arg != NULL)
    arg++;
  CHAIN_FUNCTION(opt, savename, mysavename, NULL);
  return 1;  /* success */
}

/*
  Replaces all "offending" IIS extensions (exe, dll..) with "nice" ones
*/
static int mysavename(t_hts_callbackarg *carg, httrackp *opt, const char* adr_complete, const char* fil_complete, const char* referer_adr, const char* referer_fil, char* save) {
  static const char* iisBogus[]        = { ".com", ".exe", ".dll", ".sh", NULL };
  static const char* iisBogusReplace[] = { ".c0m", ".ex3", ".dl1", ".5h", NULL }; /* MUST be the same sizes */
  char* a;

  /* Call parent functions if multiple callbacks are chained. */
  if (CALLBACKARG_PREV_FUN(carg, savename) != NULL) {
    if (!CALLBACKARG_PREV_FUN(carg, savename)(CALLBACKARG_PREV_CARG(carg), opt, adr_complete, fil_complete, referer_adr, referer_fil, save)) {
      return 0;  /* Abort */
    }
  }

  /* Process */
  for(a = save ; *a != '\0' ; a++) {
    int i;
    for(i = 0 ; iisBogus[i] != NULL ; i++) {
      int j;
      for(j = 0 ; iisBogus[i][j] == a[j] && iisBogus[i][j] != '\0' ; j++);
      if (iisBogus[i][j] == '\0' && ( a[j] == '\0' || a[j] == '/' || a[j] == '\\' ) ) {
        strncpy(a, iisBogusReplace[i], strlen(iisBogusReplace[i]));
        break;
      }
    }
  }

  return 1;  /* success */
}