gpgsa.cpp

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#include <septentrio_gnss_driver/parsers/nmea_parsers/gpgsa.hpp>
 
const std::string GpgsaParser::MESSAGE_ID = "$GPGSA";
 
const std::string GpgsaParser::getMessageID() const
{
    return GpgsaParser::MESSAGE_ID;
}
 
GpgsaMsg GpgsaParser::parseASCII(const NMEASentence& sentence,
                                 const std::string& frame_id, bool /*use_gnss_time*/,
                                 Timestamp /*time_obj*/) noexcept(false)
{
 
    // Checking the length first, it should be 19 elements
    const size_t LENGTH = 19;
    if (sentence.get_body().size() != LENGTH)
    {
        std::stringstream error;
        error << "Expected GPGSA length is " << LENGTH << ". The actual length is "
              << sentence.get_body().size();
        throw ParseException(error.str());
    }
 
    GpgsaMsg msg;
    msg.header.frame_id = frame_id;
    msg.message_id = sentence.get_body()[0];
    msg.auto_manual_mode = sentence.get_body()[1];
    if (!parsing_utilities::parseUInt8(sentence.get_body()[2], msg.fix_mode))
    {
        std::stringstream error;
        error << "GPGSA fix_mode parsing error.";
        throw ParseException(error.str());
    }
    // Words 3-14 of the sentence are SV PRNs. Copying only the non-null strings..
    // 0 is the character needed to fill the new character space, in case 12 (first
    // argument) is larger than sv_ids.
    msg.sv_ids.resize(12, 0);
    size_t n_svs = 0;
    for (std::vector<std::string>::const_iterator id =
             sentence.get_body().begin() + 3;
         id < sentence.get_body().begin() + 15; ++id)
    {
        if (!id->empty())
        {
            if (!parsing_utilities::parseUInt8(*id, msg.sv_ids[n_svs]))
            {
                std::stringstream error;
                error << "GPGSA sv_ids parsing error.";
                throw ParseException(error.str());
            }
            ++n_svs;
        }
    }
    msg.sv_ids.resize(n_svs);
 
    if (!parsing_utilities::parseFloat(sentence.get_body()[15], msg.pdop))
    {
        std::stringstream error;
        error << "GPGSA pdop parsing error.";
        throw ParseException(error.str());
    }
    if (!parsing_utilities::parseFloat(sentence.get_body()[16], msg.hdop))
    {
        std::stringstream error;
        error << "GPGSA hdop parsing error.";
        throw ParseException(error.str());
    }
    if (!parsing_utilities::parseFloat(sentence.get_body()[17], msg.vdop))
    {
        std::stringstream error;
        error << "GPGSA vdop parsing error.";
        throw ParseException(error.str());
    }
    return msg;
}