/* inet_pton.c -- convert IPv4 and IPv6 addresses from text to binary form

   Copyright (C) 2006 Free Software Foundation, Inc.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 2, or (at your option)
   any later version.

   This program is distributed in the hope that it will be useful,
   but WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software Foundation,
   Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.  */

/*
 * Copyright (c) 1996,1999 by Internet Software Consortium.
 *
 * Permission to use, copy, modify, and distribute this software for any
 * purpose with or without fee is hereby granted, provided that the above
 * copyright notice and this permission notice appear in all copies.
 *
 * THE SOFTWARE IS PROVIDED "AS IS" AND INTERNET SOFTWARE CONSORTIUM DISCLAIMS
 * ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL INTERNET SOFTWARE
 * CONSORTIUM BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL
 * DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR
 * PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS
 * ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 */

//port by snoj for speed test for nodejs

//http://www.koders.com/c/fid74A647B73741DDD374D5478366A00584E8740D43.aspx 
 function inet_pton6 (src)
{
  //static const char xdigits[] = "0123456789abcdef";
  //unsigned char tmp[NS_IN6ADDRSZ], *tp, *endp, *colonp;
  //const char *curtok;

  //int ch, saw_xdigit;
  //unsigned val;
  
  var xdigits, tmp, tp, endp, colonp, curtok, ch, saw_xdigit, val;
  
  xdigits = "0123456789abcdef";
  tmp = [0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0];
  //tp = memset (tmp, '\0', NS_IN6ADDRSZ);
  //endp = tp + NS_IN6ADDRSZ; end pointer (basically the length);
  
  colonp = null;
  endp = 16;
  tp = 0;
  /* Leading :: requires sme special handling. */
  if (src[0] == ':' && src[1] != ':') { 
    //console.log("address starts with one :");
    return 0;
  }
    //if (*src != ':')
      //return (0);
  //curtok = src;
  saw_xdigit = 0;
  val = 0;
  //while ((ch = tolower (*src++)) != '\0')
  src = src.toLowerCase();
  for(var i = 0; i<src.length; i++)
    {
      ch = parseInt(src[i],16) //src.charCodeAt(i)
      //const char *pch;
      var pch;

      //pch = strchr (xdigits, ch);
      //pch = xdigits.indexOf(String.fromCharCode(ch));
      pch = xdigits.indexOf(src[i]);
      if (pch != -1)
	{
	  val <<= 4;
	  //val |= (pch - xdigits);
	  val |= (ch);
	  if (val > 0xffff) {
	    //console.log("val > %s", 0xffff);
	    return (0);
	  }
	  saw_xdigit = 1;
	  continue;
	}
      if (src[i] == ':')
	{
	  curtok = i;
	  if (!saw_xdigit)
	    {
	      if (colonp) {
	      	//console.log("colonp not null?");
		return (0);
	      }
	      colonp = tp;
	      continue;
	    }
	  else if (src[i] == '\0') //probably can delete this?
	    {
	      //console.log("wtf?")
	      return (0);
	    }
	  //if (tp + NS_INT16SZ > endp)
	  if ((tp + 2) > 16) {
	    //console.log("tp + 2 > 16");
	    return (0);
	  }
	  //*tp++ = (u_char) (val >> 8) & 0xff;
	  //*tp++ = (u_char) val & 0xff;
	  //tmp[tp++] = String.fromCharCode((val >> 8) &0xff)
	  //tmp[tp++] = String.fromCharCode((val) &0xff)
	  //console.log("tp = %s", tp);
	  //console.log(((val >> 8) & 0xff).toString(16));
	  //console.log(((val) &0xff).toString(16));
	  tmp[tp++] = ((val >> 8) & 0xff)//.toString(16) //.replace(/(0.)([a-f].)/i, '$2');
	  tmp[tp++] = ((val) & 0xff)//.toString(16) //.replace(/(0.)([a-f].)/i, '$2');
	  //tmp[tp++] = (val >> 8)
	  saw_xdigit = 0;
	  val = 0;
	  continue;
	}
      /*if (ch == '.' && ((tp + NS_INADDRSZ) <= endp) &&
	  inet_pton4 (curtok, tp) > 0)
	{
	  tp += NS_INADDRSZ;
	  saw_xdigit = 0;
	  break;		/* '\0' was seen by inet_pton4(). * /
	}*/
      //console.log("end of for loop");
      return (0);
    }
  if (saw_xdigit)
    {
      //if (tp + NS_INT16SZ > endp)
      if ((tp + 2) > 16) {
	//console.log("tp + 2 > 16");
	return (0);
      }
      //*tp++ = (u_char) (val >> 8) & 0xff;
      //*tp++ = (u_char) val & 0xff;
      //console.log(val);
      //tmp[tp++] = String.fromCharCode((val >> 8) &0xff)
      //tmp[tp++] = String.fromCharCode((val) &0xff)
      tmp[tp++] = ((val >> 8) &0xff)//.toString(16) //.replace(/(0.)([a-f].)/i, '$2');
      tmp[tp++] = ((val) &0xff)//.toString(16) //.replace(/(0.)([a-f].)/i, '$2');
    }
    //console.log(tmp);
  if (colonp != null)
    {
      /*
       * Since some memmove()'s erroneously fail to handle
       * overlapping regions, we'll do the shift by hand.
       */
      //const int n = tp - colonp;
      //int i;
      n = tp - colonp;
      
      if (tp == endp) {
      	//console.log("tp == endp");
	return (0);
      }
      //console.log("tp = %s, n = %s", tp , n);
      for (var i = 0; i <= n; i++)
	{
	  //endp[-i] = colonp[n - i];
	  //colonp[n - i] = 0;
	  //console.log("tmp[16-i] = %s, n = %s, colonp = %s, tmp[n+i] = %s", tmp[15-i], n, colonp, tmp[n+i]);
	  tmp[15-i] = tmp[n+i];
	  tmp[n+i] = 0;
	}
      tp = endp;
    }
  if (tp != endp) {
    //console.log("now tp != endp");
    return (0);
  }
  //memcpy (dst, tmp, NS_IN6ADDRSZ);
  //return (1);
  //console.log("eol");
  return tmp.slice(0,15);
}

console.log(inet_pton6("::"));
console.log(inet_pton6("::a"));
console.log(inet_pton6("a::"));
console.log(inet_pton6("ffaa:FFFF::1a:a"));
console.log(inet_pton6("0000:0000:0000:0000:0000:0000:0000:0000::0000"));
console.time("inet_pton");
for(var i = 0; i< 10000; i++) {
	inet_pton6("0000:0000:0000:0000:0000:0000:0000:0000::0000");
}
console.timeEnd("inet_pton");