#include "utils.h"
#include <algorithm> // transform
#include <fstream>
#include <sstream>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <string>
#include <time.h>

// http://c-faq.com/lib/randrange.html
int randint(int N) { return rand() / (RAND_MAX / N + 1); }

// http://c-faq.com/lib/randrange.html
// numbers in the range [M, N] could be generated with something like

int randrange(int M, int N) {
  return M + rand() / (RAND_MAX / (N - M + 1) + 1);
}

/**
 * random_activate()
 *
 * Is a weight (1-10),
 * tests if random number is < weight * 10.
 *
 * So random_activate(9) happens more frequently
 * then random_activate(8) or lower.
 *
 * This probably needs to be fixed.
 * We need a better randint(RANGE) code.
 */
int random_activate(int w) {
  int r = randint(100);
  if (r <= w) {
    return 1;
  };
  return 0;
}

/**
 * Display a repr of the given string.
 *
 * This converts most \n\r\v\f\t codes,
 * defaults to \xHH (hex value).
 */
char *repr(const char *data) {
  static char buffer[40960];
  char *cp;

  strcpy(buffer, data);
  cp = buffer;
  while (*cp != 0) {
    char c = *cp;

    if (c == ' ') {
      cp++;
      continue;
    };
    /* Ok, it's form-feed ('\f'), newline ('\n'), carriage return ('\r'),
     * horizontal tab ('\t'), and vertical tab ('\v') */
    if (strchr("\f\n\r\t\v\?", c) != NULL) {
      memmove(cp + 1, cp, strlen(cp) + 1);
      *cp = '\\';
      cp++;
      switch (c) {
      case '\f':
        *cp = 'f';
        cp++;
        break;
      case '\n':
        *cp = 'n';
        cp++;
        break;
      case '\r':
        *cp = 'r';
        cp++;
        break;
      case '\t':
        *cp = 't';
        cp++;
        break;
      case '\v':
        *cp = 'v';
        cp++;
        break;
      default:
        *cp = '?';
        cp++;
        break;
      }
      continue;
    }

    if (c == '\\') {
      memmove(cp + 1, cp, strlen(cp) + 1);
      *cp = '\\';
      cp += 2;
      continue;
    }
    if (c == '"') {
      memmove(cp + 1, cp, strlen(cp) + 1);
      *cp = '\\';
      cp += 2;
      continue;
    }
    if (strchr("[()]{}:;,.<>?!@#$%^&*", c) != NULL) {
      cp++;
      continue;
    }
    if (strchr("0123456789", c) != NULL) {
      cp++;
      continue;
    }
    if (strchr("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ", c) !=
        NULL) {
      cp++;
      continue;
    }

    // Ok, default to \xHH output.
    memmove(cp + 3, cp, strlen(cp) + 1);
    char buffer[10];
    // int slen =
    snprintf(buffer, sizeof(buffer), "\\x%02x", (int)c & 0xff);
    /*
    if (slen >= sizeof(buffer)) {
      ZF_LOGE("snprintf %d > size %d", slen, (int)sizeof(buffer));
    }
    */
    strncpy(cp, buffer, 4);
    cp += 4;
    continue;
  }

  return buffer;
}

/*
 * strnstr()
 *
 * buffer safe version that looks for a string.
 */
const char *strnstr(const char *source, int len, const char *needle) {
  int pos;

  for (pos = 0; pos < len; pos++) {
    if (source[pos] == needle[0]) {
      if (strncmp(source + pos, needle, strlen(needle)) == 0) {
        return source + pos;
      }
    }
  }
  return NULL;
}

/*
 * rstrnstr() Reverse string find in a string
 *
 * This obeys the len, and handles nulls in buffer.
 * find is a c-string (null terminated)
 */
int rstrnstr(const char *buffer, int len, const char *find) {
  int flen = strlen(find);

  if (len < flen) {
    // I can't find a string in a buffer smaller then it is!
    return -1;
  }
  int pos = len - flen;
  while (pos > 0) {
    if (buffer[pos] == find[0]) {
      // First chars match, check them all.
      if (strncmp(buffer + pos, find, flen) == 0) {
        return pos;
      }
    }
    pos--;
  }
  return -1;
}

/*
 * string_insert()
 * Inserts a string into a given position.
 * This safely checks to make sure the buffer isn't overrun.
 *
 * buffer is a c null terminated string.
 */
int string_insert(char *buffer, size_t max_length, size_t pos,
                  const char *insert) {
  /*
  assert(max_length > pos);
  assert(buffer != NULL);
  assert(insert != NULL);
  */
  if (pos >= max_length)
    return 0;
  if (buffer == NULL)
    return 0;
  if (insert == NULL)
    return 0;
  if (strlen(insert) == 0)
    return 0;
  if (pos > strlen(buffer))
    return 0;

  if (strlen(buffer) + strlen(insert) >= max_length) {
    /*
    ZF_LOGD("string_insert() failed inserting [%s]", repr(insert));
    */
    return 0;
  }
  memmove(buffer + pos + strlen(insert), buffer + pos,
          strlen(buffer + pos) + 1);
  // cp + strlen(display), cp, strlen(cp) + 1);
  strncpy(buffer + pos, insert, strlen(insert));
  // (cp, display, strlen(display));
  return 1; // success
}

void remove_all(std::string &str, char c) {
  str.erase(std::remove(str.begin(), str.end(), c), str.end());
}

int unicode_len(char choad) {
  /*
    return length of unicode sequence, or 0 if not a unicode.
   */

  // https://en.wikipedia.org/wiki/UTF-8
  
  // 110xxxxx
  if ((choad & 0xe0) == 0xc0) {
    // CHOAD!
    return 2;
  }
  // 1110xxxx
  if ((choad & 0xf0) == 0xe0) {
    return 3;
  }
  // 11110xxx
  if ((choad & 0xf8) == 0xf0) {
    return 4;
  }
  return 0;
}

/*
Pascal String Copy.  Copy from pascal string, to C String.

First char is pascal string length.  (Max 255).
 */
void pcopy(char *pstring, char *str) {
  int len = (int)*pstring;
  strncpy(str, pstring + 1, len);
  str[len] = 0;
}

/*
 * tail file, return new lines of text.
 *
 * Only handles lines < 256 chars.
 * Does not handle if the file is closed/unlinked/...
 *
 */
std::string &find_new_text(std::ifstream &infile,
                           std::streampos &last_position) {
  static std::string line;
  line.clear();

  infile.seekg(0, std::ios::end);
  std::streampos filesize = infile.tellg();

  if (filesize == -1) {
    // Ok, we've failed somehow.  Now what?
    // cout << "SNAP!";
    return line;
  }

  // check if the new file started
  // we don't detect if the file has been unlinked/reset
  if (filesize < last_position) {
    // cout << "reset! " << filesize << endl;
    last_position = 0;
  }

  while (last_position < filesize) {
    // this loop -- seems broken.
    // for (long n = last_position; n < filesize; n++) {

    infile.seekg(last_position, std::ios::beg);

    char test[256];
    infile.getline(test, sizeof(test));

    if (infile.eof()) {
      // We got EOF instead of something.
      // Seek back to our last, good, known position
      // and exit (wait for the rest of the line)
      infile.seekg(last_position, std::ios::beg);
      return line;
    }

    std::streampos new_pos = infile.tellg();
    if (new_pos == -1)
      return line;

    last_position = new_pos;
    line.assign(test);
    return line;
  }
  return line;
}

void string_toupper(std::string &str) {
  std::transform(str.begin(), str.end(), str.begin(), ::toupper);
}

void string_trim(std::string &value) {
  while (*value.begin() == ' ')
    value.erase(value.begin());
  while (*(value.end() - 1) == ' ')
    value.erase(value.end() - 1);
}

std::map<std::string, std::string> read_configfile(std::string filename) {
  std::ifstream file(filename);
  std::string line;
  std::map<std::string, std::string> config;
  if (!file.is_open())
    return config;

  while (std::getline(file, line)) {
    if ((line[0] == '#') || (line[0] == ';'))
      continue;
    if (line.empty())
      continue;

    // I'm not so sure this part is very good.

    std::istringstream is_line(line);
    std::string key;
    if (std::getline(is_line, key, '=')) {
      string_trim(key);
      string_toupper(key);

      std::string value;
      if (std::getline(is_line, value)) {
        string_trim(value);

        config[key] = value;
        /*
                std::cout << "Key: [" << key << "] Value: [" << value << "]"
                          << std::endl;
        */
      }
    }
  }

  return config;
}

bool replace(std::string &str, const std::string &from, const std::string &to) {
  size_t start_pos = str.find(from);
  if (start_pos == std::string::npos)
    return false;
  str.replace(start_pos, from.length(), to);
  return true;
}

IConv::IConv(const char *to, const char *from) : ic(iconv_open(to, from)) {}
IConv::~IConv() { iconv_close(ic); }

int IConv::convert(char *input, char *output, size_t outbufsize) {
  size_t inbufsize = strlen(input);
  // size_t orig_size = outbufsize;
  // memset(output, 0, outbufsize);
  // https://www.gnu.org/savannah-checkouts/gnu/libiconv/documentation/libiconv-1.15/iconv.3.html
  int r = iconv(ic, &input, &inbufsize, &output, &outbufsize);
  *output = 0;
  return r;
}

static IConv converter("UTF-8", "CP437");

static time_t last_time = 0;

std::map<std::string, std::string> CONFIG = read_configfile("hharry.cfg");

/*
 * harry_level:
 *
 *  0 - inactive
 *  1 - Week 1 (1-7)
 *  2 - Week 2 (8-14)
 *  3 - Week 3 (15-21)
 *  4 - Week 4 (22-31)
 */
int harry_level(void) {
  struct tm *tmp;
  time_t now = time(NULL);
  static int last = 0;

  auto search = CONFIG.find("LEVEL");
  if (search != CONFIG.end()) {
    last = stoi(search->second);
    if (last > 4) {
      last = 4;
    }
    if (last < 0) {
      last = 0;
    }
    return last;
  }

  if (last_time < now + 10) {
    last_time = now;
    // Do our every 10 second checks here

    tmp = gmtime(&now);
    if (tmp->tm_mon != 9)
      return (last = 0);
    if (tmp->tm_mday < 8)
      return (last = 1);
    if (tmp->tm_mday < 15)
      return (last = 2);
    if (tmp->tm_mday < 22)
      return (last = 3);
    return (last = 4);
  }
  return last;
}

/*
 * This is similar to repr, but --
 *
 * It converts high ASCII to UTF8, so it will display correctly
 * in the logfiles!
 */
const char *logrepr(const char *input) {
  static char buffer[10240];
  char *cp;

  strcpy(buffer, input);
  cp = buffer;
  while (*cp != 0) {
    unsigned char c = *cp;

    if (c == ' ') {
      cp++;
      continue;
    };
    /* Ok, it's form-feed ('\f'), newline ('\n'), carriage return ('\r'),
     * horizontal tab ('\t'), and vertical tab ('\v') */
    if (strchr("\f\n\r\t\v", c) != NULL) {
      memmove(cp + 1, cp, strlen(cp) + 1);
      *cp = '\\';
      cp++;
      switch (c) {
      case '\f':
        *cp = 'f';
        cp++;
        break;
      case '\n':
        *cp = 'n';
        cp++;
        break;
      case '\r':
        *cp = 'r';
        cp++;
        break;
      case '\t':
        *cp = 't';
        cp++;
        break;
      case '\v':
        *cp = 'v';
        cp++;
        break;
        /*      default:
                *cp = '?';
                cp++;
                break; */
      }
      continue;
    }

    if (c == '\\') {
      memmove(cp + 1, cp, strlen(cp) + 1);
      *cp = '\\';
      cp += 2;
      continue;
    }
    if (c == '"') {
      memmove(cp + 1, cp, strlen(cp) + 1);
      *cp = '\\';
      cp += 2;
      continue;
    }
    if (strchr("[()]{}:;,.<>?!@#$%^&*", c) != NULL) {
      cp++;
      continue;
    }
    if (strchr("0123456789", c) != NULL) {
      cp++;
      continue;
    }
    if (strchr("abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ", c) !=
        NULL) {
      cp++;
      continue;
    }

    if ((int)c < 0x20) {
      // Ok, default to \xHH output.
      memmove(cp + 3, cp, strlen(cp) + 1);
      char buffer[10];
      // int slen =
      snprintf(buffer, sizeof(buffer), "\\x%02x", (int)c & 0xff);
      strncpy(cp, buffer, 4);
      cp += 4;
      continue;
    };
    cp++;
    continue;
  }

  static char fancybuffer[16384];
  converter.convert(buffer, fancybuffer, sizeof(fancybuffer));
  return fancybuffer;
}