util.h

#pragma once

inline std::string regexExtract(const std::string &regexstr, const std::string &payload)
{
    std::regex regex(regexstr);
    std::smatch match;
    if (!std::regex_search(payload, match, regex) || match.size() != 2) {
        //std::cerr << "Failed to get match for '" << regexstr << "' in:\n" << payload << std::endl;
        return "";
    }
    return match[1].str();
}

inline bool extractNumber(const std::string &regex, const std::string &payload, double *number)
{
    const std::string numberString = regexExtract(regex, payload);
    if (numberString.empty()) {
        //std::cerr << "Failed to extract number '" << regex << "'" << std::endl;
        return false;
    }
    char *endptr = nullptr;
    const char *startptr = numberString.c_str();
    const double converted = strtod(startptr, &endptr);
    if (endptr == startptr || errno == ERANGE || !std::isfinite(converted)) {
        return false;
    }
    *number = converted;

    return true;
}

inline std::vector<std::string> stringSplit(const std::string &string, const char delimiter)
{
    std::vector<std::string> ret;

    std::string::size_type start = 0;
    while (start < string.size()) {
        std::string::size_type end = string.find(delimiter, start);
        if (end == std::string::npos) {
            break;
        }
        ret.push_back(string.substr(start, end - start));
        start = end + 1;
    }
    ret.push_back(string.substr(start));

    return ret;
}