//
// Copyright 2016 Ettus Research LLC
// Copyright 2018 Ettus Research, a National Instruments Company
//
// SPDX-License-Identifier: GPL-3.0-or-later
//

#include <uhd/exception.hpp>
#include <uhd/usrp/fe_connection.hpp>
#include <uhd/utils/math.hpp>
#include <regex>

using namespace uhd::usrp;

fe_connection_t::fe_connection_t(sampling_t sampling_mode,
    bool iq_swapped,
    bool i_inverted,
    bool q_inverted,
    double if_freq)
    : _sampling_mode(sampling_mode)
    , _iq_swapped(iq_swapped)
    , _i_inverted(i_inverted)
    , _q_inverted(q_inverted)
    , _if_freq(if_freq)
{
}

fe_connection_t::fe_connection_t(const std::string& conn_str, double if_freq)
{
    static const std::regex conn_regex("([IQ])(b?)(([IQ])(b?))?");
    std::cmatch matches;
    if (std::regex_match(conn_str.c_str(), matches, conn_regex)) {
        if (matches[3].length() == 0) {
            // Connection in {I, Q, Ib, Qb}
            _sampling_mode = REAL;
            _iq_swapped    = (matches[1].str() == "Q");
            _i_inverted    = (matches[2].length() != 0);
            _q_inverted    = false; // IQ is swapped after inversion
        } else {
            // Connection in {I(b?)Q(b?), Q(b?)I(b?), I(b?)I(b?), Q(b?)Q(b?)}
            _sampling_mode = (matches[1].str() == matches[4].str()) ? HETERODYNE
                                                                    : QUADRATURE;
            _iq_swapped  = (matches[1].str() == "Q");
            size_t i_idx = _iq_swapped ? 5 : 2, q_idx = _iq_swapped ? 2 : 5;
            _i_inverted = (matches[i_idx].length() != 0);
            _q_inverted = (matches[q_idx].length() != 0);

            if (_sampling_mode == HETERODYNE and _i_inverted != _q_inverted) {
                throw uhd::value_error("Invalid connection string: " + conn_str);
            }
        }
        _if_freq = if_freq;
    } else {
        throw uhd::value_error("Invalid connection string: " + conn_str);
    }
}

bool uhd::usrp::operator==(const fe_connection_t& lhs, const fe_connection_t& rhs)
{
    return ((lhs.get_sampling_mode() == rhs.get_sampling_mode())
            and (lhs.is_iq_swapped() == rhs.is_iq_swapped())
            and (lhs.is_i_inverted() == rhs.is_i_inverted())
            and (lhs.is_q_inverted() == rhs.is_q_inverted())
            and uhd::math::frequencies_are_equal(lhs.get_if_freq(), rhs.get_if_freq()));
}