//
// Copyright 2010-2012,2014 Ettus Research LLC
// Copyright 2018 Ettus Research, a National Instruments Company
//
// SPDX-License-Identifier: GPL-3.0-or-later
//

#include <uhd/types/tune_request.hpp>
#include <uhd/utils/thread.hpp>
#include <uhd/utils/safe_main.hpp>
#include <uhd/usrp/multi_usrp.hpp>
#include <uhd/transport/udp_simple.hpp>
#include <uhd/exception.hpp>
#include <boost/program_options.hpp>
#include <boost/format.hpp>
#include <iostream>
#include <complex>
#include <chrono>
#include <thread>

namespace po = boost::program_options;

int UHD_SAFE_MAIN(int argc, char *argv[]){
    uhd::set_thread_priority_safe();

    //variables to be set by po
    std::string args, file, ant, subdev, ref;
    size_t total_num_samps;
    double rate, freq, gain, bw;
    std::string addr, port;

    //setup the program options
    po::options_description desc("Allowed options");
    desc.add_options()
        ("help", "help message")
        ("args", po::value<std::string>(&args)->default_value(""), "multi uhd device address args")
        ("nsamps", po::value<size_t>(&total_num_samps)->default_value(1000), "total number of samples to receive")
        ("rate", po::value<double>(&rate)->default_value(100e6/16), "rate of incoming samples")
        ("freq", po::value<double>(&freq)->default_value(0), "rf center frequency in Hz")
        ("gain", po::value<double>(&gain)->default_value(0), "gain for the RF chain")
        ("ant", po::value<std::string>(&ant), "antenna selection")
        ("subdev", po::value<std::string>(&subdev), "subdevice specification")
        ("bw", po::value<double>(&bw), "analog frontend filter bandwidth in Hz")
        ("port", po::value<std::string>(&port)->default_value("7124"), "server udp port")
        ("addr", po::value<std::string>(&addr)->default_value("192.168.1.10"), "resolvable server address")
        ("ref", po::value<std::string>(&ref)->default_value("internal"), "reference source (internal, external, mimo)")
        ("int-n", "tune USRP with integer-N tuning")
    ;
    po::variables_map vm;
    po::store(po::parse_command_line(argc, argv, desc), vm);
    po::notify(vm);

    //print the help message
    if (vm.count("help")){
        std::cout << boost::format("UHD RX to UDP %s") % desc << std::endl;
        return ~0;
    }

    //create a usrp device
    std::cout << std::endl;
    std::cout << boost::format("Creating the usrp device with: %s...") % args << std::endl;
    uhd::usrp::multi_usrp::sptr usrp = uhd::usrp::multi_usrp::make(args);
    std::cout << boost::format("Using Device: %s") % usrp->get_pp_string() << std::endl;

    //Lock mboard clocks
    usrp->set_clock_source(ref);

    //always select the subdevice first, the channel mapping affects the other settings
    if (vm.count("subdev")) {
        usrp->set_rx_subdev_spec(subdev);
    }

    //set the rx sample rate
    std::cout << boost::format("Setting RX Rate: %f Msps...") % (rate/1e6) << std::endl;
    usrp->set_rx_rate(rate);
    std::cout << boost::format("Actual RX Rate: %f Msps...") % (usrp->get_rx_rate()/1e6) << std::endl << std::endl;

    //set the rx center frequency
    std::cout << boost::format("Setting RX Freq: %f MHz...") % (freq/1e6) << std::endl;
    uhd::tune_request_t tune_request(freq);
    if(vm.count("int-n")) tune_request.args = uhd::device_addr_t("mode_n=integer");
    usrp->set_rx_freq(tune_request);
    std::cout << boost::format("Actual RX Freq: %f MHz...") % (usrp->get_rx_freq()/1e6) << std::endl << std::endl;

    //set the rx rf gain
    std::cout << boost::format("Setting RX Gain: %f dB...") % gain << std::endl;
    usrp->set_rx_gain(gain);
    std::cout << boost::format("Actual RX Gain: %f dB...") % usrp->get_rx_gain() << std::endl << std::endl;

    //set the analog frontend filter bandwidth
    if (vm.count("bw")){
        std::cout << boost::format("Setting RX Bandwidth: %f MHz...") % (bw/1e6) << std::endl;
        usrp->set_rx_bandwidth(bw);
        std::cout << boost::format("Actual RX Bandwidth: %f MHz...") % (usrp->get_rx_bandwidth()/1e6) << std::endl << std::endl;
    }

    //set the antenna
    if (vm.count("ant")) usrp->set_rx_antenna(ant);

    std::this_thread::sleep_for(std::chrono::seconds(1)); //allow for some setup time

    //Check Ref and LO Lock detect
    std::vector<std::string> sensor_names;
    sensor_names = usrp->get_rx_sensor_names(0);
    if (std::find(sensor_names.begin(), sensor_names.end(), "lo_locked") != sensor_names.end()) {
        uhd::sensor_value_t lo_locked = usrp->get_rx_sensor("lo_locked",0);
        std::cout << boost::format("Checking RX: %s ...") % lo_locked.to_pp_string() << std::endl;
        UHD_ASSERT_THROW(lo_locked.to_bool());
    }
    sensor_names = usrp->get_mboard_sensor_names(0);
    if ((ref == "mimo") and (std::find(sensor_names.begin(), sensor_names.end(), "mimo_locked") != sensor_names.end())) {
        uhd::sensor_value_t mimo_locked = usrp->get_mboard_sensor("mimo_locked",0);
        std::cout << boost::format("Checking RX: %s ...") % mimo_locked.to_pp_string() << std::endl;
        UHD_ASSERT_THROW(mimo_locked.to_bool());
    }
    if ((ref == "external") and (std::find(sensor_names.begin(), sensor_names.end(), "ref_locked") != sensor_names.end())) {
        uhd::sensor_value_t ref_locked = usrp->get_mboard_sensor("ref_locked",0);
        std::cout << boost::format("Checking RX: %s ...") % ref_locked.to_pp_string() << std::endl;
        UHD_ASSERT_THROW(ref_locked.to_bool());
    }

    //create a receive streamer
    uhd::stream_args_t stream_args("fc32"); //complex floats
    uhd::rx_streamer::sptr rx_stream = usrp->get_rx_stream(stream_args);

    //setup streaming
    uhd::stream_cmd_t stream_cmd(uhd::stream_cmd_t::STREAM_MODE_NUM_SAMPS_AND_DONE);
    stream_cmd.num_samps = total_num_samps;
    stream_cmd.stream_now = true;
    rx_stream->issue_stream_cmd(stream_cmd);

    //loop until total number of samples reached
    size_t num_acc_samps = 0; //number of accumulated samples
    uhd::rx_metadata_t md;
    std::vector<std::complex<float> > buff(rx_stream->get_max_num_samps());
    uhd::transport::udp_simple::sptr udp_xport = uhd::transport::udp_simple::make_connected(addr, port);

    while(num_acc_samps < total_num_samps){
        size_t num_rx_samps = rx_stream->recv(
            &buff.front(), buff.size(), md
        );

        //handle the error codes
        switch(md.error_code){
        case uhd::rx_metadata_t::ERROR_CODE_NONE:
            break;

        case uhd::rx_metadata_t::ERROR_CODE_TIMEOUT:
            if (num_acc_samps == 0) continue;
            std::cout << boost::format(
                "Got timeout before all samples received, possible packet loss, exiting loop..."
            ) << std::endl;
            goto done_loop;

        default:
            std::cout << boost::format(
                "Got error code 0x%x, exiting loop..."
            ) % md.error_code << std::endl;
            goto done_loop;
        }

        //send complex single precision floating point samples over udp
        udp_xport->send(boost::asio::buffer(buff, num_rx_samps*sizeof(buff.front())));

        num_acc_samps += num_rx_samps;
    } done_loop:

    //finished
    std::cout << std::endl << "Done!" << std::endl << std::endl;

    return EXIT_SUCCESS;
}