/*
*  C Implementation: lessons
*
* Description: 
*
*
* Author: David Bruce <davidstuartbruce@gmail.com>, (C) 2007
*
* Copyright: See COPYING file that comes with this distribution
*
*/
#include <stdio.h>
//for strtok()
#include <string.h>
#include "lessons.h"
//for basename(), if available
#ifdef HAVE_LIBGEN_H
#include <libgen.h>
#endif

// extern unsigned char **lesson_list_titles;
// extern unsigned char **lesson_list_filenames;
int* lesson_list_goldstars = NULL;
// extern int num_lessons;

/* local function prototypes: */
static int filename_comp(const char* s1, const char* s2);

/* Reads the file pointed to by the arg and sets */
/* lesson_list_goldstars* accordingly:           */
int read_goldstars_fp(FILE* fp)
{
  char buf[PATH_MAX];
  char* token;
  const char delimiters[] = "\t\n\r"; /* this will keep newline chars out of string */
  int i;

  DEBUGMSG(debug_lessons, "Entering read_goldstars_fp()\n");

  /* get out if file pointer invalid: */
  if(!fp)
  {
    fprintf(stderr, "In read_goldstars_fp(), file pointer invalid!\n");
    return 0;
  }

  if (num_lessons <= 0)
  {
    perror("no lessons - returning");
    num_lessons = 0;
    return 0;
  }



  /* make sure we start at beginning: */
  rewind(fp);

  /* read in a line at a time: */
  while (fgets (buf, PATH_MAX, fp))
  { 
    /* Ignore comment lines: */
    if ((buf[0] == ';') || (buf[0] == '#'))
    {
      continue;
    }

    /* Split up line with strtok()to get needed values -    */ 
    /* for now, each line just contains a lesson file name, */
    /* but eventually there may be more fields (e.g date, % correct) */
    token = strtok(buf, delimiters);
    if (!token)
      continue;

    /* Now set "goldstar" to 1 if we find a matching lesson: */
    for (i = 0; i < num_lessons; i++)
    {
      /* compare basenames only, not entire path (see below): */
      if (0 == filename_comp(token, lesson_list_filenames[i]))
      {
        lesson_list_goldstars[i] = 1;
        break; //should not have to worry about duplicates
      }
    }
  }
  return 1;
}


/* Write lessons gold star list to the provided FILE* in format  */
/* compatible with read_goldstars_fp () above.            */

void write_goldstars_fp(FILE* fp)
{
  int i = 0;

  DEBUGMSG(debug_lessons, "Entering write_goldstars_fp()\n");

  /* get out if file pointer invalid: */
  if(!fp)
  {
    fprintf(stderr, "In write_goldstars_fp(), file pointer invalid!\n");
    return;
  }

  /* make sure we start at beginning: */
  rewind(fp);

  for (i = 0; i < num_lessons; i++)
  {
    DEBUGMSG(debug_lessons, "i = %d\nfilename = %s\ngoldstar = %d\n",
             i, lesson_list_filenames[i],
             lesson_list_goldstars[i]);

    if(lesson_list_goldstars[i] == 1)
    {
      fprintf(fp, "%s\n", lesson_list_filenames[i]);
    }
  }
  return;
}


/* Perform a strcasecmp() on two path strings, stripping away all the */
/* dirs in the path and just comparing the filenames themselves:      */
/* FIXME: basename() may not be available on all platforms.           */
/* If not available, just compare the full paths. Consider including  */
/* our own implementation at some point. Note that the docs say       */
/* basename() takes a const char*, but the actual header is char*,    */
/* hence the casts to reassure the compiler.                          */
static int filename_comp(const char* s1, const char* s2)
{
#ifdef HAVE_BASENAME
  return strcasecmp(basename((char*)s1), basename((char*)s2));
#else
  return strcasecmp(s1, s2);
#endif
}