//
// Copyright 2011 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/thread_priority.hpp>
#include <uhd/utils/safe_main.hpp>
#include <uhd/usrp/multi_usrp.hpp>
#include <boost/program_options.hpp>
#include <boost/format.hpp>
#include <boost/thread/thread.hpp>
#include <boost/math/special_functions/round.hpp>
#include <iostream>
#include <complex>

namespace po = boost::program_options;

/***********************************************************************
 * Test result variables
 **********************************************************************/
unsigned long long num_overflows = 0;
unsigned long long num_underflows = 0;
unsigned long long num_rx_samps = 0;
unsigned long long num_tx_samps = 0;
unsigned long long num_dropped_samps = 0;
unsigned long long num_seq_errors = 0;

/***********************************************************************
 * Benchmark RX Rate
 **********************************************************************/
void benchmark_rx_rate(uhd::usrp::multi_usrp::sptr usrp){
    uhd::set_thread_priority_safe();

    //print pre-test summary
    std::cout << boost::format(
        "Testing receive rate %f Msps"
    ) % (usrp->get_rx_rate()/1e6) << std::endl;

    //setup variables and allocate buffer
    uhd::rx_metadata_t md;
    const size_t max_samps_per_packet = usrp->get_device()->get_max_recv_samps_per_packet();
    std::vector<std::complex<float> > buff(max_samps_per_packet);
    bool had_an_overflow = false;
    uhd::time_spec_t last_time;
    const double rate = usrp->get_rx_rate();

    usrp->issue_stream_cmd(uhd::stream_cmd_t::STREAM_MODE_START_CONTINUOUS);
    while (not boost::this_thread::interruption_requested()){
        num_rx_samps += usrp->get_device()->recv(
            &buff.front(), buff.size(), md,
            uhd::io_type_t::COMPLEX_FLOAT32,
            uhd::device::RECV_MODE_ONE_PACKET
        );

        //handle the error codes
        switch(md.error_code){
        case uhd::rx_metadata_t::ERROR_CODE_NONE:
            if (had_an_overflow){
                had_an_overflow = false;
                num_dropped_samps += boost::math::iround((md.time_spec - last_time).get_real_secs()*rate);
            }
            break;

        case uhd::rx_metadata_t::ERROR_CODE_OVERFLOW:
            had_an_overflow = true;
            last_time = md.time_spec;
            num_overflows++;
            break;

        default:
            std::cerr << "Error code: " << md.error_code << std::endl;
            std::cerr << "Unexpected error on recv, continuing..." << std::endl;
            break;
        }

    }
    usrp->issue_stream_cmd(uhd::stream_cmd_t::STREAM_MODE_STOP_CONTINUOUS);
}

/***********************************************************************
 * Benchmark TX Rate
 **********************************************************************/
void benchmark_tx_rate(uhd::usrp::multi_usrp::sptr usrp){
    uhd::set_thread_priority_safe();

    //print pre-test summary
    std::cout << boost::format(
        "Testing transmit rate %f Msps"
    ) % (usrp->get_tx_rate()/1e6) << std::endl;

    //setup variables and allocate buffer
    uhd::tx_metadata_t md;
    md.has_time_spec = false;
    const size_t max_samps_per_packet = usrp->get_device()->get_max_send_samps_per_packet();
    std::vector<std::complex<float> > buff(max_samps_per_packet);

    while (not boost::this_thread::interruption_requested()){
        num_tx_samps += usrp->get_device()->send(
            &buff.front(), buff.size(), md,
            uhd::io_type_t::COMPLEX_FLOAT32,
            uhd::device::SEND_MODE_ONE_PACKET
        );
    }

    //send a mini EOB packet
    md.end_of_burst   = true;
    usrp->get_device()->send("", 0, md,
        uhd::io_type_t::COMPLEX_FLOAT32,
        uhd::device::SEND_MODE_FULL_BUFF
    );
}

void benchmark_tx_rate_async_helper(uhd::usrp::multi_usrp::sptr usrp){
    //setup variables and allocate buffer
    uhd::async_metadata_t async_md;

    while (true){

        if (not usrp->get_device()->recv_async_msg(async_md)){
            if (boost::this_thread::interruption_requested()) return;
        }

        //handle the error codes
        switch(async_md.event_code){
        case uhd::async_metadata_t::EVENT_CODE_BURST_ACK:
            return;

        case uhd::async_metadata_t::EVENT_CODE_UNDERFLOW:
        case uhd::async_metadata_t::EVENT_CODE_UNDERFLOW_IN_PACKET:
            num_underflows++;
            break;

        case uhd::async_metadata_t::EVENT_CODE_SEQ_ERROR:
        case uhd::async_metadata_t::EVENT_CODE_SEQ_ERROR_IN_BURST:
            num_seq_errors++;
            break;

        default:
            std::cerr << "Event code: " << async_md.event_code << std::endl;
            std::cerr << "Unexpected event on async recv, continuing..." << std::endl;
            break;
        }
    }
}

/***********************************************************************
 * Main code + dispatcher
 **********************************************************************/
int UHD_SAFE_MAIN(int argc, char *argv[]){

    //variables to be set by po
    std::string args;
    double duration;
    double rx_rate, tx_rate;

    //setup the program options
    po::options_description desc("Allowed options");
    desc.add_options()
        ("help", "help message")
        ("args", po::value<std::string>(&args)->default_value(""), "single uhd device address args")
        ("duration", po::value<double>(&duration)->default_value(10.0), "duration for the test in seconds")
        ("rx_rate", po::value<double>(&rx_rate), "specify to perform a RX rate test (sps)")
        ("tx_rate", po::value<double>(&tx_rate), "specify to perform a TX rate test (sps)")
    ;
    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 Benchmark Rate %s") % desc << std::endl;
        std::cout <<
        "    Specify --rx_rate for a receive-only test.\n"
        "    Specify --tx_rate for a transmit-only test.\n"
        "    Specify both options for a full-duplex test.\n"
        << std::endl;
        return ~0;
    }

    //create a usrp device
    std::cout << std::endl;
    uhd::device_addrs_t device_addrs = uhd::device::find(args);
    if (not device_addrs.empty() and device_addrs.at(0).get("type", "") == "usrp1"){
        std::cerr << "*** Warning! ***" << std::endl;
        std::cerr << "Benchmark results will be inaccurate on USRP1 due to insufficient features.\n" << 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;

    boost::thread_group thread_group;

    //spawn the receive test thread
    if (vm.count("rx_rate")){
        usrp->set_rx_rate(rx_rate);
        thread_group.create_thread(boost::bind(&benchmark_rx_rate, usrp));
    }

    //spawn the transmit test thread
    if (vm.count("tx_rate")){
        usrp->set_tx_rate(tx_rate);
        thread_group.create_thread(boost::bind(&benchmark_tx_rate, usrp));
        thread_group.create_thread(boost::bind(&benchmark_tx_rate_async_helper, usrp));
    }

    //sleep for the required duration
    const long secs = long(duration);
    const long usecs = long((duration - secs)*1e6);
    boost::this_thread::sleep(boost::posix_time::seconds(secs) + boost::posix_time::microseconds(usecs));

    //interrupt and join the threads
    thread_group.interrupt_all();
    thread_group.join_all();

    //print summary
    std::cout << std::endl << boost::format(
        "Benchmark rate summary:\n"
        "  Num received samples:    %u\n"
        "  Num dropped samples:     %u\n"
        "  Num overflows detected:  %u\n"
        "  Num transmitted samples: %u\n"
        "  Num sequence errors:     %u\n"
        "  Num underflows detected: %u\n"
    ) % num_rx_samps % num_dropped_samps % num_overflows % num_tx_samps % num_seq_errors % num_underflows << std::endl;

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

    return 0;
}