num_to_string.hpp

/*******************************************************************************
 *
 * Copyright (c) Simon Downey <[email protected]>
 *
 * The MIT License (MIT)
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to
 * deal in the Software without restriction, including without limitation the
 * rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 * sell copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 ******************************************************************************/

#ifndef NUM_TO_STRING_HPP
#define NUM_TO_STRING_HPP

#include <string>

inline const std::string NumToString(int64_t amount) {
    if (amount == 0) {
        return "0";
    }

    const uint8_t STRING_SIZE   = 24U;
    const char *STRING_TABLE    = "0123456789";

    uint64_t temp = amount < 0 ? -amount : amount;

    std::string result;
    result.reserve(STRING_SIZE);

    while (temp != 0U) {
        result += STRING_TABLE[temp % BASE_10];
        temp /= BASE_10;
    }

    if (amount < 0) {
      result.insert(result.end(), '-');
    }

    std::reverse(result.begin(), result.end());

    return result;
}

inline const std::string NumToFloatString(int64_t amount, size_t decimals) {
    std::string result = NumToString(amount);

    if (decimals > result.length() - (amount < 0) - 1 ||
        result == "0") {
      return {};
    }

    if (decimals > 0) {
      result.insert(result.end() - decimals , '.');
    }

    return result;
}

#endif  //#define NUM_TO_STRING_HPP