//
// Copyright 2010 Ettus Research LLC
//
// This program 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.
//
// This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
//

#include <uhd/utils/safe_main.hpp>
#include <uhd/usrp/simple_usrp.hpp>
#include <boost/program_options.hpp>
#include <boost/format.hpp>
#include <iostream>
#include <fstream>
#include <complex>

namespace po = boost::program_options;

int UHD_SAFE_MAIN(int argc, char *argv[]){
    //variables to be set by po
    std::string args, file_path;
    int seconds_in_future;
    size_t total_num_samps;
    double rx_rate, freq;

    //setup the program options
    po::options_description desc("Allowed options");
    desc.add_options()
        ("help", "help message")
        ("args", po::value<std::string>(&args)->default_value(""), "simple uhd device address args")
        ("secs", po::value<int>(&seconds_in_future)->default_value(3), "number of seconds in the future to receive")
        ("nsamps", po::value<size_t>(&total_num_samps)->default_value(1000), "total number of samples to receive")
        ("rxrate", po::value<double>(&rx_rate)->default_value(100e6/16), "rate of incoming samples")
        ("freq", po::value<double>(&freq)->default_value(0), "rf center frequency in Hz")
        ("file", po::value<std::string>(&file_path)->default_value(""), "write samps to output file")
    ;
    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 Timed Samples %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::simple_usrp::sptr sdev = uhd::usrp::simple_usrp::make(args);
    uhd::device::sptr dev = sdev->get_device();
    std::cout << boost::format("Using Device: %s") % sdev->get_name() << std::endl;

    //set properties on the device
    std::cout << boost::format("Setting RX Rate: %f Msps...") % (rx_rate/1e6) << std::endl;
    sdev->set_rx_rate(rx_rate);
    std::cout << boost::format("Actual RX Rate: %f Msps...") % (sdev->get_rx_rate()/1e6) << std::endl;
    std::cout << boost::format("Setting device timestamp to 0...") << std::endl;
    sdev->set_rx_freq(freq);
    sdev->set_time_now(uhd::time_spec_t(0));

    //setup streaming
    std::cout << std::endl;
    std::cout << boost::format("Begin streaming %u samples, %d seconds in the future...")
        % total_num_samps % seconds_in_future << std::endl;
    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 = false;
    stream_cmd.time_spec = uhd::time_spec_t(seconds_in_future);
    sdev->issue_stream_cmd(stream_cmd);

    std::ofstream outfile;
    if(file_path != "") outfile.open (file_path.c_str(), std::ios::out | std::ios::binary);

    //setup recv buffer, io type, and metadata for recv
    uhd::rx_metadata_t md;
    uhd::io_type_t io_type(uhd::io_type_t::COMPLEX_INT16);
    std::vector<std::complex<float> > recv_mem(dev->get_max_recv_samps_per_packet());
    boost::asio::mutable_buffer buff(boost::asio::buffer(recv_mem));

    //loop until total number of samples reached
    size_t num_acc_samps = 0; //number of accumulated samples
    while(num_acc_samps < total_num_samps){
        size_t num_rx_samps = dev->recv(
            buff, md, io_type,
            uhd::device::RECV_MODE_ONE_PACKET
        );
        if (num_rx_samps == 0 and num_acc_samps > 0){
            std::cout << "Got timeout before all samples received, possible packet loss, exiting loop..." << std::endl;
            break;
        }
        if (num_rx_samps == 0) continue; //wait for packets with contents

        std::cout << boost::format("Got packet: %u samples, %u secs, %u nsecs")
            % num_rx_samps % md.time_spec.secs % md.time_spec.nsecs << std::endl;

        if(file_path != "") outfile.write(boost::asio::buffer_cast<const char *>(buff), num_rx_samps*io_type.size);

        num_acc_samps += num_rx_samps;
    }

    //finished
    std::cout << std::endl << "Done!" << std::endl << std::endl;
    if(file_path != "") outfile.close();

    return 0;
}