/**
 * Copyright (c) 2012, PICHOT Fabien Paul Leonard <pichot.fabienATgmail.com>
 * Copyright (c) 2012, Tristan Le Guern <tleguern@bouledef.eu>
 *
 * Permission to use, copy, modify, and/or 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 THE AUTHOR DISCLAIMS ALL WARRANTIES WITH
 * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY
 * AND FITNESS. IN NO EVENT SHALL THE AUTHOR 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.
 **/

#if defined Windows
#include <windows.h>
#endif
#include <ctype.h>
#include <stdint.h>
#include <stdio.h>
#include <string.h>

#include <llarp/logger.hpp>
#include "tuntap.h"

extern "C"
{
  void
  tuntap_log_set_cb(t_tuntap_log cb)
  {
    if(cb == NULL)
    {
      tuntap_log = tuntap_log_default;
    }
    tuntap_log = cb;
  }

  void
  tuntap_log_default(int level, const char *errmsg)
  {
    switch(level)
    {
      case TUNTAP_LOG_DEBUG:
        llarp::LogDebug(errmsg);
        break;
      case TUNTAP_LOG_INFO:
        llarp::LogInfo(errmsg);
        break;
      case TUNTAP_LOG_NOTICE:
        llarp::LogInfo(errmsg);
        break;
      case TUNTAP_LOG_WARN:
        llarp::LogWarn(errmsg);
        break;
      case TUNTAP_LOG_ERR:
        llarp::LogError(errmsg);
        break;
      case TUNTAP_LOG_NONE:
      default:
        return;
    }
  }

  void
  tuntap_log_hexdump(void *data, size_t size)
  {
    unsigned char *p = (unsigned char *)data;
    unsigned int c;
    size_t n;
    char bytestr[4]          = {0};
    char addrstr[10]         = {0};
    char hexstr[16 * 3 + 5]  = {0};
    char charstr[16 * 1 + 5] = {0};
    char buf[1024];

    for(n = 1; n <= size; n++)
    {
      if(n % 16 == 1)
      {
        /* store address for this line */
        snprintf(addrstr, sizeof(addrstr), "%.4lx",
                 ((uintptr_t)p - (uintptr_t)data));
      }

      c = *p;
      if(isalnum(c) == 0)
      {
        c = '.';
      }

      /* store hex str (for left side) */
      snprintf(bytestr, sizeof(bytestr), "%02X ", *p);
      strncat(hexstr, bytestr, sizeof(hexstr) - strlen(hexstr) - 1);

      /* store char str (for right side) */
      snprintf(bytestr, sizeof(bytestr), "%c", c);
      strncat(charstr, bytestr, sizeof(charstr) - strlen(charstr) - 1);

      if(n % 16 == 0)
      {
        /* line completed */
        (void)memset(buf, 0, sizeof buf);
        (void)snprintf(buf, sizeof buf, "[%4.4s]   %-50.50s  %s", addrstr,
                       hexstr, charstr);
        tuntap_log(TUNTAP_LOG_NONE, buf);
        hexstr[0]  = 0;
        charstr[0] = 0;
      }
      else if(n % 8 == 0)
      {
        /* half line: add whitespaces */
        strncat(hexstr, "  ", sizeof(hexstr) - strlen(hexstr) - 1);
        strncat(charstr, " ", sizeof(charstr) - strlen(charstr) - 1);
      }
      p++; /* next byte */
    }

    /* print the rest of the buffer if not empty */
    if(strlen(hexstr) > 0)
    {
      (void)memset(buf, 0, sizeof buf);
      (void)snprintf(buf, sizeof buf, "[%4.4s]   %-50.50s  %s", addrstr, hexstr,
                     charstr);
      tuntap_log(TUNTAP_LOG_NONE, buf);
    }
  }

  void
  tuntap_log_chksum(void *addr, int count)
  {
    int sum;
    short *sptr;
    char buf[32];

    sum  = 0;
    sptr = (short *)addr;
    while(count > 1)
    {
      sum   = sum + *sptr;
      count = count - 2;
      sptr++;
    }

    addr = (char *)sptr;
    if(count > 0)
      sum = sum + *((char *)addr);
    sum = ~sum;

    (void)memset(buf, 0, sizeof buf);
    (void)snprintf(buf, sizeof buf, "Checksum of this block: %0#4x", sum);
    tuntap_log(TUNTAP_LOG_NONE, buf);
  }
}