/*         ______   ___    ___ 
 *        /\  _  \ /\_ \  /\_ \ 
 *        \ \ \L\ \\//\ \ \//\ \      __     __   _ __   ___ 
 *         \ \  __ \ \ \ \  \ \ \   /'__`\ /'_ `\/\`'__\/ __`\
 *          \ \ \/\ \ \_\ \_ \_\ \_/\  __//\ \L\ \ \ \//\ \L\ \
 *           \ \_\ \_\/\____\/\____\ \____\ \____ \ \_\\ \____/
 *            \/_/\/_/\/____/\/____/\/____/\/___L\ \/_/ \/___/
 *                                           /\____/
 *                                           \_/__/
 *
 *      Makedoc's miscellaneous functions
 *
 *      By Shawn Hargreaves.
 *
 *      Grzegorz Adam Hankiewicz added safe memory/io functions.
 *
 *      See readme.txt for copyright information.
 *
 *      See allegro/docs/src/makedoc/format.txt for a brief description of
 *      the source of _tx files.
 */

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

#include "makemisc.h"

#define _CHUNK 100


/* myisalum:
 */
int myisalnum(int c)
{
   return (((c >= '0') && (c <= '9')) ||
	   ((c >= 'A') && (c <= 'Z')) ||
	   ((c >= 'a') && (c <= 'z')) ||
	   (c >= 0x80) || (c < 0));
}



/* mytolower:
 */
int mytolower(int c)
{
   if ((c >= 'A') && (c <= 'Z'))
      c -= ('A' - 'a');

   return c;
}



/* mystricmp:
 */
int mystricmp(const char *s1, const char *s2)
{
   int c1, c2;

   do {
      c1 = mytolower(*(s1++));
      c2 = mytolower(*(s2++));
   } while ((c1) && (c1 == c2));

   return c1 - c2;
}



/* mystristr:
 * Like strstr but ignoring case during comparisons.
 */
char *mystristr(const char *HAYSTACK, const char *NEEDLE)
{
   const char *end;
   assert(HAYSTACK);
   assert(NEEDLE);
   assert(strlen(NEEDLE) > 0);

   end = strchr(HAYSTACK, 0) - strlen(NEEDLE);
   while (HAYSTACK <= end) {
      if (strincmp(HAYSTACK, NEEDLE) == 0)
	 return (char*)HAYSTACK;
      HAYSTACK++;
   }
   return 0;
}



/* mystrlwr:
 */
char *mystrlwr(char *string)
{
   char *p;

   for (p=string; *p; p++)
      *p = mytolower(*p);

   return string;
}



/* strincmp:
 * Compares two strings ignoring case up to s2's length.
 */
int strincmp(const char *s1, const char *s2)
{
   while (*s2) {
      if (mytolower(*s1) != mytolower(*s2))
	 return 1;

      s1++;
      s2++;
   }

   return 0;
}



/* myisspace:
 */
int myisspace(int c)
{
   return ((c == ' ') || (c == '\t') || (c == '\r') || 
	   (c == '\n') || (c == '\f') || (c == '\v'));
}



/* strip_html:
 */
char *strip_html(char *p)
{
   static char buf[256];
   int c;

   c = 0;
   while (*p) {
      if (*p == '<') {
	 while ((*p) && (*p != '>'))
	    p++;
	 if (*p)
	    p++;
      }
      else {
	 buf[c] = *p;
	 c++;
	 p++;
      }
   }

   buf[c] = 0;

   return buf;
}



/* is_empty:
 * Returns true if the string constist of something more than space or tabs.
 */
int is_empty(char *s)
{
   while (*s) {
      if ((*s) != ' ' && (*s) != '\t')
	 return 0;

      s++;
   }

   return 1;
}



/* get_filename:
 */
char *get_filename(const char *path)
{
   int pos;

   for (pos=0; path[pos]; pos++)
      ; /* do nothing */ 

   while ((pos>0) && (path[pos-1] != '\\') && (path[pos-1] != '/'))
      pos--;

   return (char*)path+pos;
}



/* get_extension:
 * If filename contains a dot, this function will return a pointer to the
 * first character after the dot. Otherwise it returns a pointer to the
 * end of the string, position which holds the string terminator.
 */
char *get_extension(const char *filename)
{
   int pos, end;

   for (end=0; filename[end]; end++)
      ; /* do nothing */

   pos = end;

   while ((pos>0) && (filename[pos-1] != '.') &&
	  (filename[pos-1] != '\\') && (filename[pos-1] != '/'))
      pos--;

   if (filename[pos-1] == '.')
      return (char*)filename+pos;

   return (char*)filename+end;
}



/* scmp:
 */
int scmp(const void *e1, const void *e2)
{
   char *s1 = *((char **)e1);
   char *s2 = *((char **)e2);

   return mystricmp(s1, s2);
}



/* get_clean_ref_token:
 * Given a text, extracts the clean ref token, which either has to be
 * surrounded by "ss#..", inside a <a name=".." tag, or without any
 * html characters around. Otherwise returns an empty string. The
 * returned string has to be freed always.
 */
char *get_clean_ref_token(const char *text)
{
   char *buf, *t;
   const char *pname, *pcross;

   pname = strstr(text, "<a name=\"");
   pcross = strstr(text, "ss#");
   if (pname && pcross) { /* Take the first one */
      if (pname < pcross)
	 pcross = 0;
      else
	 pname = 0;
   }

   if (pname) {
      buf = m_strdup(pname + 9);
      t = strchr(buf, '"');
      *t = 0;
   }
   else if (pcross) {
      buf = m_strdup(pcross + 3);
      t = strchr(buf, '"');
      *t = 0;
   }
   else if (!strchr(text, '<') && !strchr(text, '>'))
      buf = m_strdup(text);
   else { /* this is mainly for debugging */
      printf("'%s' was rejected as clean ref token\n", text);
      buf = m_strdup("");
   }
   assert(buf);
   return buf;
}



/* m_xmalloc:
 * Returns the requested chunk of memory. If there's not enough
 * memory, the program will abort.
 */
void *m_xmalloc(size_t size)
{
   void *p = malloc(size);
   if (!p) m_abort(1);
   return p;
}



/* m_xrealloc:
 * Wrapper around real realloc call. Returns the new chunk of memory or
 * aborts execution if it couldn't realloc it.
 */
void *m_xrealloc(void *ptr, size_t new_size)
{
   if (!ptr)
      return m_xmalloc(new_size);
   ptr = realloc(ptr, new_size);
   if (!ptr) m_abort(1);
   return ptr;
}



/* m_abort:
 * Aborts execution with a hopefully meaningful message. If code is less
 * than 1, an undefined exit will happen. Available error codes:
 * 1: insufficient memory
 */
void m_abort(int code)
{
   switch(code) {
      case 1:  printf("Aborting due to insuficcient memory\n"); break;
      default: printf("An undefined error caused abnormal termination\n");
   }
   abort();
}



/* m_strdup:
 * Safe wrapper around strdup, always returns the duplicated string.
 */
char *m_strdup(const char *text)
{
   char *p = m_xmalloc(strlen(text)+1);
   return strcpy(p, text);
}



/* m_fgets:
 * Safe function to read text lines from a file. Returns the read line
 * or NULL when you reach the end of the file or there's a problem.
 */
char *m_fgets(FILE *file)
{
   int read, filled = 0, size = 0;
   char *buf = 0;

   while ((read = getc(file)) != EOF) {
      while (filled + 2 >= size) {
	 size += _CHUNK;
	 buf = m_xrealloc(buf, size);
      }
      if (read != '\r')
	 buf[filled++] = read;
      buf[filled] = 0;

      if (read == '\n')
	 break;
   }

   return buf;
}



/* m_strcat:
 * Special strcat function, which is a mixture of realloc and strcat.
 * The first parameter has to be a pointer to dynamic memory, since it's
 * space will be resized with m_xrealloc (it can be NULL). The second
 * pointer can be any type of string, and will be appended to the first
 * one. This function returns a new pointer to the memory holding both
 * strings.
 */
char *m_strcat(char *dynamic_string, const char *normal_string)
{
   int len;

   if(!dynamic_string)
      return m_strdup(normal_string);

   len = strlen(dynamic_string);
   dynamic_string = m_xrealloc(dynamic_string, 1 + len + strlen(normal_string));
   strcpy(dynamic_string + len, normal_string);
   return dynamic_string;
}



/* m_replace_extension:
 * Replaces the extension (any text after last dot in string and after last
 * path separator) in path with the new one. If there's no dot in path, path
 * and extension will be concatenated like '"%s.%s", path, extension'.
 * Returns the created string, which has to be freed. Usage example:
 *    char *dest = m_replace_extension(argv[2], "html");
 */
char *m_replace_extension(const char *path, const char *extension)
{
   char *p;
   assert(path);
   assert(extension);

   p = get_extension(path);
   if(*p) {
      int len = p - path;
      char *temp = m_xmalloc(len + 1 + strlen(extension));
      strncpy(temp, path, len);
      strcpy(temp+len, extension);
      return temp;
   }
   else {
      char *temp = m_xmalloc(strlen(path) + 2 + strlen(extension));
      sprintf(temp, "%s.%s", path, extension);
      return temp;
   }
}



/* m_replace_filename:
 * Replaces the filename (any text after the last slash or backslash in
 * the string) in the path with the new one. If there's no slash or
 * backslash in the path, path and filename will be concatenated like
 * '%s/%s', path, filename'. Returns the created string, which has to be
 * freed. Usage example:
 *    char *dest = m_replace_filename(argv[2], "out.html");
 */
char *m_replace_filename(const char *path, const char *filename)
{
   char *p;
   assert(path);
   assert(filename);

   p = get_filename(path);
   if(*p) {
      int len = p - path;
      char *temp = m_xmalloc(len + 1 + strlen(filename));
      strncpy(temp, path, len);
      strcpy(temp+len, filename);
      return temp;
   }
   else {
      char *temp = m_xmalloc(strlen(path) + 2 + strlen(filename));
      sprintf(temp, "%s/%s", path, filename);
      return temp;
   }
}