/*!
 * \file gps_l2_m_dll_pll_tracking_fpga.cc
 * \brief Implementation of an adapter of a DLL+PLL tracking loop block
 * for GPS L2C to a TrackingInterface for the FPGA
 * \author Javier Arribas, 2019. jarribas(at)cttc.es
 *
 * Code DLL + carrier PLL according to the algorithms described in:
 * K.Borre, D.M.Akos, N.Bertelsen, P.Rinder, and S.H.Jensen,
 * A Software-Defined GPS and Galileo Receiver. A Single-Frequency
 * Approach, Birkhauser, 2007
 *
 * -------------------------------------------------------------------------
 *
 * Copyright (C) 2010-2019  (see AUTHORS file for a list of contributors)
 *
 * GNSS-SDR is a software defined Global Navigation
 *          Satellite Systems receiver
 *
 * This file is part of GNSS-SDR.
 *
 * GNSS-SDR is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * GNSS-SDR is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with GNSS-SDR. If not, see <https://www.gnu.org/licenses/>.
 *
 * -------------------------------------------------------------------------
 */


#include "gps_l2_m_dll_pll_tracking_fpga.h"
#include "GPS_L2C.h"
#include "configuration_interface.h"
#include "display.h"
#include "dll_pll_conf_fpga.h"
#include "gnss_sdr_flags.h"
#include "gnss_synchro.h"
#include "gps_l2c_signal.h"
#include <glog/logging.h>
#include <volk_gnsssdr/volk_gnsssdr_alloc.h>
#include <array>
#include <cmath>    // for round
#include <cstring>  // for memcpy
#include <iostream>

GpsL2MDllPllTrackingFpga::GpsL2MDllPllTrackingFpga(
    ConfigurationInterface* configuration, const std::string& role,
    unsigned int in_streams, unsigned int out_streams) : role_(role), in_streams_(in_streams), out_streams_(out_streams)
{
    Dll_Pll_Conf_Fpga trk_param_fpga = Dll_Pll_Conf_Fpga();
    DLOG(INFO) << "role " << role;
    // ################# CONFIGURATION PARAMETERS ########################
    int fs_in_deprecated = configuration->property("GNSS-SDR.internal_fs_hz", 2048000);
    int fs_in = configuration->property("GNSS-SDR.internal_fs_sps", fs_in_deprecated);
    trk_param_fpga.fs_in = fs_in;
    bool dump = configuration->property(role + ".dump", false);
    trk_param_fpga.dump = dump;
    std::string default_dump_filename = "./track_ch";
    std::string dump_filename = configuration->property(role + ".dump_filename", default_dump_filename);
    trk_param_fpga.dump_filename = dump_filename;
    bool dump_mat = configuration->property(role + ".dump_mat", true);
    trk_param_fpga.dump_mat = dump_mat;
    float pll_bw_hz = configuration->property(role + ".pll_bw_hz", 2.0);
    if (FLAGS_pll_bw_hz != 0.0)
        {
            pll_bw_hz = static_cast<float>(FLAGS_pll_bw_hz);
        }
    trk_param_fpga.pll_bw_hz = pll_bw_hz;
    float dll_bw_hz = configuration->property(role + ".dll_bw_hz", 0.75);
    if (FLAGS_dll_bw_hz != 0.0)
        {
            dll_bw_hz = static_cast<float>(FLAGS_dll_bw_hz);
        }
    trk_param_fpga.dll_bw_hz = dll_bw_hz;
    float early_late_space_chips = configuration->property(role + ".early_late_space_chips", 0.5);
    trk_param_fpga.early_late_space_chips = early_late_space_chips;
    trk_param_fpga.early_late_space_narrow_chips = 0.0;
    int vector_length = std::round(static_cast<double>(fs_in) / (static_cast<double>(GPS_L2_M_CODE_RATE_CPS) / static_cast<double>(GPS_L2_M_CODE_LENGTH_CHIPS)));
    trk_param_fpga.vector_length = vector_length;
    int symbols_extended_correlator = configuration->property(role + ".extend_correlation_symbols", 1);
    if (symbols_extended_correlator != 1)
        {
            std::cout << TEXT_RED << "WARNING: Extended coherent integration is not allowed in GPS L2. Coherent integration has been set to 20 ms (1 symbol)" << TEXT_RESET << std::endl;
        }
    trk_param_fpga.extend_correlation_symbols = 1;
    bool track_pilot = configuration->property(role + ".track_pilot", false);
    if (track_pilot)
        {
            std::cout << TEXT_RED << "WARNING: GPS L2 does not have pilot signal. Data tracking has been enabled" << TEXT_RESET << std::endl;
        }
    trk_param_fpga.track_pilot = false;
    trk_param_fpga.very_early_late_space_chips = 0.0;
    trk_param_fpga.very_early_late_space_narrow_chips = 0.0;
    trk_param_fpga.pll_bw_narrow_hz = 0.0;
    trk_param_fpga.dll_bw_narrow_hz = 0.0;
    trk_param_fpga.system = 'G';
    std::array<char, 3> sig_{'2', 'S', '\0'};
    std::memcpy(trk_param_fpga.signal, sig_.data(), 3);
    trk_param_fpga.cn0_samples = configuration->property(role + ".cn0_samples", trk_param_fpga.cn0_samples);
    trk_param_fpga.cn0_min = configuration->property(role + ".cn0_min", trk_param_fpga.cn0_min);
    trk_param_fpga.max_code_lock_fail = configuration->property(role + ".max_lock_fail", trk_param_fpga.max_code_lock_fail);
    trk_param_fpga.max_carrier_lock_fail = configuration->property(role + ".max_carrier_lock_fail", trk_param_fpga.max_carrier_lock_fail);
    trk_param_fpga.carrier_lock_th = configuration->property(role + ".carrier_lock_th", trk_param_fpga.carrier_lock_th);
    trk_param_fpga.cn0_smoother_samples = configuration->property(role + ".cn0_smoother_samples", trk_param_fpga.cn0_smoother_samples);
    trk_param_fpga.cn0_smoother_alpha = configuration->property(role + ".cn0_smoother_alpha", trk_param_fpga.cn0_smoother_alpha);
    trk_param_fpga.carrier_lock_test_smoother_samples = configuration->property(role + ".carrier_lock_test_smoother_samples", trk_param_fpga.carrier_lock_test_smoother_samples);
    trk_param_fpga.carrier_lock_test_smoother_alpha = configuration->property(role + ".carrier_lock_test_smoother_alpha", trk_param_fpga.carrier_lock_test_smoother_alpha);

    // FPGA configuration parameters
    std::string default_device_name = "/dev/uio";
    std::string device_name = configuration->property(role + ".devicename", default_device_name);
    trk_param_fpga.device_name = device_name;
    // obtain the number of the first uio device file that is assigned to the FPGA L2 tracking multicorrelator HW accelerators
    trk_param_fpga.dev_file_num = configuration->property(role + ".dev_file_num", 27);
    // compute the number of tracking channels that have already been instantiated. The order in which
    // GNSS-SDR instantiates the tracking channels i L1, L2, L5, E1, E5a
    trk_param_fpga.num_prev_assigned_ch = configuration->property("Channels_1C.count", 0);

    volk_gnsssdr::vector<float> ca_codes_f(static_cast<unsigned int>(GPS_L2_M_CODE_LENGTH_CHIPS), 0.0);
    // ################# PRE-COMPUTE ALL THE CODES #################
    d_ca_codes = static_cast<int*>(volk_gnsssdr_malloc(static_cast<int>(GPS_L2_M_CODE_LENGTH_CHIPS * NUM_PRNs) * sizeof(int), volk_gnsssdr_get_alignment()));
    for (uint32_t PRN = 1; PRN <= NUM_PRNs; PRN++)
        {
            gps_l2c_m_code_gen_float(ca_codes_f, PRN);
            for (unsigned int s = 0; s < 2 * static_cast<unsigned int>(GPS_L2_M_CODE_LENGTH_CHIPS); s++)
                {
                    d_ca_codes[static_cast<int>(GPS_L2_M_CODE_LENGTH_CHIPS) * (PRN - 1) + s] = static_cast<int>(ca_codes_f[s]);
                }
        }

    trk_param_fpga.ca_codes = d_ca_codes;
    trk_param_fpga.code_length_chips = GPS_L2_M_CODE_LENGTH_CHIPS;
    trk_param_fpga.code_samples_per_chip = 1;  // 1 sample per chip

    // ################# MAKE TRACKING GNU Radio object ###################
    tracking_fpga_sc = dll_pll_veml_make_tracking_fpga(trk_param_fpga);

    channel_ = 0;
    DLOG(INFO) << "tracking(" << tracking_fpga_sc->unique_id() << ")";

    if (in_streams_ > 1)
        {
            LOG(ERROR) << "This implementation only supports one input stream";
        }
    if (out_streams_ > 1)
        {
            LOG(ERROR) << "This implementation only supports one output stream";
        }
}


GpsL2MDllPllTrackingFpga::~GpsL2MDllPllTrackingFpga()
{
    volk_gnsssdr_free(d_ca_codes);
}


void GpsL2MDllPllTrackingFpga::start_tracking()
{
    tracking_fpga_sc->start_tracking();
}


void GpsL2MDllPllTrackingFpga::stop_tracking()
{
    tracking_fpga_sc->stop_tracking();
}


/*
 * Set tracking channel unique ID
 */
void GpsL2MDllPllTrackingFpga::set_channel(unsigned int channel)
{
    channel_ = channel;
    tracking_fpga_sc->set_channel(channel);
}


void GpsL2MDllPllTrackingFpga::set_gnss_synchro(Gnss_Synchro* p_gnss_synchro)
{
    tracking_fpga_sc->set_gnss_synchro(p_gnss_synchro);
}


void GpsL2MDllPllTrackingFpga::connect(gr::top_block_sptr top_block)
{
    if (top_block)
        { /* top_block is not null */
        };
    // nothing to connect
}


void GpsL2MDllPllTrackingFpga::disconnect(gr::top_block_sptr top_block)
{
    if (top_block)
        { /* top_block is not null */
        };
    // nothing to disconnect
}


gr::basic_block_sptr GpsL2MDllPllTrackingFpga::get_left_block()
{
    return tracking_fpga_sc;
}


gr::basic_block_sptr GpsL2MDllPllTrackingFpga::get_right_block()
{
    return tracking_fpga_sc;
}