/*!
 * \file gps_l5_telemetry_decoder_cc.cc
 * \brief Implementation of a CNAV message demodulator block
 * \author Antonio Ramos, 2017. antonio.ramos(at)cttc.es
 *
 * -------------------------------------------------------------------------
 *
 * Copyright (C) 2010-2018  (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_l5_telemetry_decoder_cc.h"
#include "display.h"
#include "gnss_synchro.h"
#include "gps_cnav_ephemeris.h"
#include "gps_cnav_iono.h"
#include <boost/lexical_cast.hpp>
#include <glog/logging.h>
#include <gnuradio/io_signature.h>
#include <bitset>
#include <iostream>
#include <sstream>


using google::LogMessage;

gps_l5_telemetry_decoder_cc_sptr
gps_l5_make_telemetry_decoder_cc(const Gnss_Satellite &satellite, bool dump)
{
    return gps_l5_telemetry_decoder_cc_sptr(new gps_l5_telemetry_decoder_cc(satellite, dump));
}


gps_l5_telemetry_decoder_cc::gps_l5_telemetry_decoder_cc(
    const Gnss_Satellite &satellite, bool dump) : gr::block("gps_l5_telemetry_decoder_cc",
                                                      gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)),
                                                      gr::io_signature::make(1, 1, sizeof(Gnss_Synchro)))
{
    // Ephemeris data port out
    this->message_port_register_out(pmt::mp("telemetry"));
    // initialize internal vars
    d_dump = dump;
    d_satellite = Gnss_Satellite(satellite.get_system(), satellite.get_PRN());
    DLOG(INFO) << "GPS L5 TELEMETRY PROCESSING: satellite " << d_satellite;
    d_channel = 0;
    d_flag_valid_word = false;
    d_TOW_at_current_symbol_ms = 0U;
    d_TOW_at_Preamble_ms = 0U;
    // initialize the CNAV frame decoder (libswiftcnav)
    cnav_msg_decoder_init(&d_cnav_decoder);
    for (int32_t aux = 0; aux < GPS_L5I_NH_CODE_LENGTH; aux++)
        {
            if (GPS_L5I_NH_CODE[aux] == 0)
                {
                    bits_NH[aux] = -1.0;
                }
            else
                {
                    bits_NH[aux] = 1.0;
                }
        }
    sync_NH = false;
    new_sym = false;
}


gps_l5_telemetry_decoder_cc::~gps_l5_telemetry_decoder_cc()
{
    if (d_dump_file.is_open() == true)
        {
            try
                {
                    d_dump_file.close();
                }
            catch (const std::exception &ex)
                {
                    LOG(WARNING) << "Exception in destructor closing the dump file " << ex.what();
                }
        }
}


void gps_l5_telemetry_decoder_cc::set_satellite(const Gnss_Satellite &satellite)
{
    d_satellite = Gnss_Satellite(satellite.get_system(), satellite.get_PRN());
    LOG(INFO) << "GPS L5 CNAV telemetry decoder in channel " << this->d_channel << " set to satellite " << d_satellite;
    d_CNAV_Message.reset();
}


void gps_l5_telemetry_decoder_cc::set_channel(int32_t channel)
{
    d_channel = channel;
    d_CNAV_Message.reset();
    LOG(INFO) << "GPS L5 CNAV channel set to " << channel;
    // ############# ENABLE DATA FILE LOG #################
    if (d_dump == true)
        {
            if (d_dump_file.is_open() == false)
                {
                    try
                        {
                            d_dump_filename = "telemetry_L5_";
                            d_dump_filename.append(std::to_string(d_channel));
                            d_dump_filename.append(".dat");
                            d_dump_file.exceptions(std::ifstream::failbit | std::ifstream::badbit);
                            d_dump_file.open(d_dump_filename.c_str(), std::ios::out | std::ios::binary);
                            LOG(INFO) << "Telemetry decoder dump enabled on channel " << d_channel
                                      << " Log file: " << d_dump_filename.c_str();
                        }
                    catch (const std::ifstream::failure &e)
                        {
                            LOG(WARNING) << "channel " << d_channel << " Exception opening Telemetry GPS L5 dump file " << e.what();
                        }
                }
        }
}


int gps_l5_telemetry_decoder_cc::general_work(int noutput_items __attribute__((unused)), gr_vector_int &ninput_items __attribute__((unused)),
    gr_vector_const_void_star &input_items, gr_vector_void_star &output_items)
{
    // get pointers on in- and output gnss-synchro objects
    auto *out = reinterpret_cast<Gnss_Synchro *>(output_items[0]);            // Get the output buffer pointer
    const auto *in = reinterpret_cast<const Gnss_Synchro *>(input_items[0]);  // Get the input buffer pointer

    // UPDATE GNSS SYNCHRO DATA
    Gnss_Synchro current_synchro_data{};  //structure to save the synchronization information and send the output object to the next block
    // 1. Copy the current tracking output
    current_synchro_data = in[0];
    consume_each(1);  //one by one
    sym_hist.push_back(in[0].Prompt_I);
    int32_t corr_NH = 0;
    int32_t symbol_value = 0;

    // Search correlation with Neuman-Hofman Code (see IS-GPS-705D)
    if (sym_hist.size() == GPS_L5I_NH_CODE_LENGTH)
        {
            for (int32_t i = 0; i < GPS_L5I_NH_CODE_LENGTH; i++)
                {
                    if ((bits_NH[i] * sym_hist.at(i)) > 0.0)
                        {
                            corr_NH += 1;
                        }
                    else
                        {
                            corr_NH -= 1;
                        }
                }
            if (abs(corr_NH) == GPS_L5I_NH_CODE_LENGTH)
                {
                    sync_NH = true;
                    if (corr_NH > 0)
                        {
                            symbol_value = 1;
                        }
                    else
                        {
                            symbol_value = -1;
                        }
                    new_sym = true;
                    sym_hist.clear();
                }
            else
                {
                    sym_hist.pop_front();
                    sync_NH = false;
                    new_sym = false;
                }
        }

    bool flag_new_cnav_frame = false;
    cnav_msg_t msg;
    uint32_t delay = 0;

    // add the symbol to the decoder
    if (new_sym)
        {
            uint8_t symbol_clip = static_cast<uint8_t>(symbol_value > 0) * 255;
            flag_new_cnav_frame = cnav_msg_decoder_add_symbol(&d_cnav_decoder, symbol_clip, &msg, &delay);
            new_sym = false;
        }
    // 2. Add the telemetry decoder information
    // check if new CNAV frame is available
    if (flag_new_cnav_frame == true)
        {
            std::bitset<GPS_L5_CNAV_DATA_PAGE_BITS> raw_bits;
            // Expand packet bits to bitsets. Notice the reverse order of the bits sequence, required by the CNAV message decoder
            for (uint32_t i = 0; i < GPS_L5_CNAV_DATA_PAGE_BITS; i++)
                {
                    raw_bits[GPS_L5_CNAV_DATA_PAGE_BITS - 1 - i] = ((msg.raw_msg[i / 8] >> (7 - i % 8)) & 1u);
                }

            d_CNAV_Message.decode_page(raw_bits);

            // Push the new navigation data to the queues
            if (d_CNAV_Message.have_new_ephemeris() == true)
                {
                    // get ephemeris object for this SV
                    std::shared_ptr<Gps_CNAV_Ephemeris> tmp_obj = std::make_shared<Gps_CNAV_Ephemeris>(d_CNAV_Message.get_ephemeris());
                    std::cout << TEXT_MAGENTA << "New GPS L5 CNAV message received in channel " << d_channel << ": ephemeris from satellite " << d_satellite << TEXT_RESET << std::endl;
                    this->message_port_pub(pmt::mp("telemetry"), pmt::make_any(tmp_obj));
                }
            if (d_CNAV_Message.have_new_iono() == true)
                {
                    std::shared_ptr<Gps_CNAV_Iono> tmp_obj = std::make_shared<Gps_CNAV_Iono>(d_CNAV_Message.get_iono());
                    std::cout << TEXT_MAGENTA << "New GPS L5 CNAV message received in channel " << d_channel << ": iono model parameters from satellite " << d_satellite << TEXT_RESET << std::endl;
                    this->message_port_pub(pmt::mp("telemetry"), pmt::make_any(tmp_obj));
                }

            if (d_CNAV_Message.have_new_utc_model() == true)
                {
                    std::shared_ptr<Gps_CNAV_Utc_Model> tmp_obj = std::make_shared<Gps_CNAV_Utc_Model>(d_CNAV_Message.get_utc_model());
                    std::cout << TEXT_MAGENTA << "New GPS L5 CNAV message received in channel " << d_channel << ": UTC model parameters from satellite " << d_satellite << TEXT_RESET << std::endl;
                    this->message_port_pub(pmt::mp("telemetry"), pmt::make_any(tmp_obj));
                }

            // update TOW at the preamble instant
            d_TOW_at_Preamble_ms = msg.tow * 6000;
            // The time of the last input symbol can be computed from the message ToW and
            // delay by the formulae:
            // \code
            // symbolTime_ms = msg->tow * 6000 + *pdelay * 10 + (12 * 10); 12 symbols of the encoder's transitory
            d_TOW_at_current_symbol_ms = msg.tow * 6000 + (delay + 12) * GPS_L5I_SYMBOL_PERIOD_MS;
            d_flag_valid_word = true;
        }
    else
        {
            d_TOW_at_current_symbol_ms += GPS_L5I_PERIOD_MS;
            if (current_synchro_data.Flag_valid_symbol_output == false)
                {
                    d_flag_valid_word = false;
                }
        }

    if (d_flag_valid_word == true)
        {
            current_synchro_data.TOW_at_current_symbol_ms = d_TOW_at_current_symbol_ms;
            current_synchro_data.Flag_valid_word = d_flag_valid_word;

            if (d_dump == true)
                {
                    // MULTIPLEXED FILE RECORDING - Record results to file
                    try
                        {
                            double tmp_double;
                            uint64_t tmp_ulong_int;
                            tmp_double = static_cast<double>(d_TOW_at_current_symbol_ms) / 1000.0;
                            d_dump_file.write(reinterpret_cast<char *>(&tmp_double), sizeof(double));
                            tmp_ulong_int = current_synchro_data.Tracking_sample_counter;
                            d_dump_file.write(reinterpret_cast<char *>(&tmp_ulong_int), sizeof(uint64_t));
                            tmp_double = static_cast<double>(d_TOW_at_Preamble_ms) / 1000.0;
                            d_dump_file.write(reinterpret_cast<char *>(&tmp_double), sizeof(double));
                        }
                    catch (const std::ifstream::failure &e)
                        {
                            LOG(WARNING) << "Exception writing Telemetry GPS L5 dump file " << e.what();
                        }
                }

            // 3. Make the output (copy the object contents to the GNURadio reserved memory)
            out[0] = current_synchro_data;
            return 1;
        }
    return 0;
}