HackTheGame-v002/src/system/memory.cpp

#include "memory.hpp"

#include <iostream>
#include <string>
#include <cstring>

static const std::string base64_chars = 
             "abcdefghijklmnopqrstuvwxyz"
             "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
             "0123456789+/";


static inline bool is_base64(unsigned char c) {
  return (isalnum(c) || (c == '+') || (c == '/'));
}

std::string base64_encode(unsigned char const* bytes_to_encode, unsigned int in_len) {
  std::string ret;
  int i = 0;
  int j = 0;
  unsigned char char_array_3[3];
  unsigned char char_array_4[4];

  while (in_len--) {
    char_array_3[i++] = *(bytes_to_encode++);
    if (i == 3) {
      char_array_4[0] = (char_array_3[0] & 0xfc) >> 2;
      char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
      char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);
      char_array_4[3] = char_array_3[2] & 0x3f;

      for(i = 0; (i <4) ; i++)
        ret += base64_chars[char_array_4[i]];
      i = 0;
    }
  }

  if (i)
  {
    for(j = i; j < 3; j++)
      char_array_3[j] = '\0';

    char_array_4[0] = ( char_array_3[0] & 0xfc) >> 2;
    char_array_4[1] = ((char_array_3[0] & 0x03) << 4) + ((char_array_3[1] & 0xf0) >> 4);
    char_array_4[2] = ((char_array_3[1] & 0x0f) << 2) + ((char_array_3[2] & 0xc0) >> 6);

    for (j = 0; (j < i + 1); j++)
      ret += base64_chars[char_array_4[j]];

    while((i++ < 3))
      ret += '=';

  }

  return ret;

}

std::string base64_decode(std::string const& encoded_string) {
  int in_len = encoded_string.size();
  int i = 0;
  int j = 0;
  int in_ = 0;
  unsigned char char_array_4[4], char_array_3[3];
  std::string ret;

  while (in_len-- && ( encoded_string[in_] != '=') && is_base64(encoded_string[in_])) {
    char_array_4[i++] = encoded_string[in_]; in_++;
    if (i ==4) {
      for (i = 0; i <4; i++)
        char_array_4[i] = base64_chars.find(char_array_4[i]);

      char_array_3[0] = ( char_array_4[0] << 2       ) + ((char_array_4[1] & 0x30) >> 4);
      char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);
      char_array_3[2] = ((char_array_4[2] & 0x3) << 6) +   char_array_4[3];

      for (i = 0; (i < 3); i++)
        ret += char_array_3[i];
      i = 0;
    }
  }

  if (i) {
    for (j = 0; j < i; j++)
      char_array_4[j] = base64_chars.find(char_array_4[j]);

    char_array_3[0] = (char_array_4[0] << 2) + ((char_array_4[1] & 0x30) >> 4);
    char_array_3[1] = ((char_array_4[1] & 0xf) << 4) + ((char_array_4[2] & 0x3c) >> 2);

    for (j = 0; (j < i - 1); j++) ret += char_array_3[j];
  }

  return ret;
}

Player *Memory::loadFromCode(std::string code)
{
    code = base64_decode(code);
    char playerName[16] = {0};
    int playerHP = 0;
    int playerAtk = 0;
    int playerDef = 0;
    int playerLevel = 0;
    int playerExp = 0;

    int result = sscanf(code.c_str(),
                        "PlayerLevel=%d;PlayerExp=%d;PlayerHP=%d;PlayerAtk=%d;PlayerDef=%d;PlayerName=%15s",
                        &playerLevel,
                        &playerExp,
                        &playerHP,
                        &playerAtk,
                        &playerDef,
                        playerName);

    std::string playerTrueName = playerName;

    if (result == 6)
    {
        return new Player(playerTrueName, playerHP, playerAtk, playerDef, playerLevel, playerExp);
    }
    else
    {
        return nullptr;
    }
}

std::string Memory::saveToCode(Player *player)
{
    char code[256];
    snprintf(code, sizeof(code),
             "PlayerLevel=%d;PlayerExp=%d;PlayerHP=%d;PlayerAtk=%d;PlayerDef=%d;PlayerName=%s",
             player->getLevel(),
             player->getExp(),
             player->getMaxHP(),
             player->getAtk(),
             player->getDef(),
             player->getName().c_str());

    return base64_encode(reinterpret_cast<unsigned char *>(code),
                         strlen(code));
}