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/* -*- c++ -*- */
/*
 * Copyright 2012,2014-2015 Free Software Foundation, Inc.
 *
 * This file is part of GNU Radio
 *
 * SPDX-License-Identifier: GPL-3.0-or-later
 *
 */

#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

#include "freq_sink_f_impl.h"

#include <gnuradio/io_signature.h>
#include <gnuradio/prefs.h>

#include <qwt_symbol.h>
#include <volk/volk.h>

#include <string.h>

namespace gr {
namespace qtgui {


freq_sink_f::sptr freq_sink_f::make(int fftsize,
                                    int wintype,
                                    double fc,
                                    double bw,
                                    const std::string& name,
                                    int nconnections,
                                    QWidget* parent)
{
    return gnuradio::make_block_sptr<freq_sink_f_impl>(
        fftsize, wintype, fc, bw, name, nconnections, parent);
}

freq_sink_f_impl::freq_sink_f_impl(int fftsize,
                                   int wintype,
                                   double fc,
                                   double bw,
                                   const std::string& name,
                                   int nconnections,
                                   QWidget* parent)
    : sync_block("freq_sink_f",
                 io_signature::make(0, nconnections, sizeof(float)),
                 io_signature::make(0, 0, 0)),
      d_fftsize(fftsize),
      d_fft_shift(fftsize),
      d_fftavg(1.0),
      d_wintype((filter::firdes::win_type)(wintype)),
      d_center_freq(fc),
      d_bandwidth(bw),
      d_name(name),
      d_nconnections(nconnections),
      d_port(pmt::mp("freq")),
      d_port_bw(pmt::mp("bw")),
      d_parent(parent)
{
    // Required now for Qt; argc must be greater than 0 and argv
    // must have at least one valid character. Must be valid through
    // life of the qApplication:
    // http://harmattan-dev.nokia.com/docs/library/html/qt4/qapplication.html
    d_argc = 1;
    d_argv = new char;
    d_argv[0] = '\0';

    // setup bw input port
    message_port_register_in(d_port_bw);
    set_msg_handler(d_port_bw, [this](pmt::pmt_t msg) { this->handle_set_bw(msg); });

    // setup output message port to post frequency when display is
    // double-clicked
    message_port_register_out(d_port);
    message_port_register_in(d_port);
    set_msg_handler(d_port, [this](pmt::pmt_t msg) { this->handle_set_freq(msg); });

    // setup PDU handling input port
    message_port_register_in(pmt::mp("in"));
    set_msg_handler(pmt::mp("in"), [this](pmt::pmt_t msg) { this->handle_pdus(msg); });

    d_main_gui = NULL;

    // Perform fftshift operation;
    // this is usually desired when plotting
    d_shift = true;

    d_fft = new fft::fft_complex(d_fftsize, true);
    d_fbuf = (float*)volk_malloc(d_fftsize * sizeof(float), volk_get_alignment());
    memset(d_fbuf, 0, d_fftsize * sizeof(float));

    d_index = 0;
    // save the last "connection" for the PDU memory
    for (int i = 0; i < d_nconnections; i++) {
        d_residbufs.push_back(
            (float*)volk_malloc(d_fftsize * sizeof(float), volk_get_alignment()));
        d_magbufs.push_back(
            (double*)volk_malloc(d_fftsize * sizeof(double), volk_get_alignment()));

        memset(d_residbufs[i], 0, d_fftsize * sizeof(float));
        memset(d_magbufs[i], 0, d_fftsize * sizeof(double));
    }

    d_residbufs.push_back(
        (float*)volk_malloc(d_fftsize * sizeof(float), volk_get_alignment()));
    d_pdu_magbuf = (double*)volk_malloc(d_fftsize * sizeof(double), volk_get_alignment());
    d_magbufs.push_back(d_pdu_magbuf);
    memset(d_residbufs[d_nconnections], 0, d_fftsize * sizeof(float));
    memset(d_pdu_magbuf, 0, d_fftsize * sizeof(double));

    buildwindow();

    initialize();

    set_trigger_mode(TRIG_MODE_FREE, 0, 0);
}

freq_sink_f_impl::~freq_sink_f_impl()
{
    if (!d_main_gui->isClosed())
        d_main_gui->close();

    // +1 to handle PDU buffers; will also take care of d_pdu_magbuf
    for (int i = 0; i < d_nconnections + 1; i++) {
        volk_free(d_residbufs[i]);
        volk_free(d_magbufs[i]);
    }
    delete d_fft;
    volk_free(d_fbuf);

    delete d_argv;
}

bool freq_sink_f_impl::check_topology(int ninputs, int noutputs)
{
    return ninputs == d_nconnections;
}

void freq_sink_f_impl::initialize()
{
    if (qApp != NULL) {
        d_qApplication = qApp;
    } else {
#if QT_VERSION >= 0x040500 && QT_VERSION < 0x050000
        std::string style = prefs::singleton()->get_string("qtgui", "style", "raster");
        QApplication::setGraphicsSystem(QString(style.c_str()));
#endif
        d_qApplication = new QApplication(d_argc, &d_argv);
    }

    // If a style sheet is set in the prefs file, enable it here.
    check_set_qss(d_qApplication);

    int numplots = (d_nconnections > 0) ? d_nconnections : 1;
    d_main_gui = new FreqDisplayForm(numplots, d_parent);
    set_fft_window(d_wintype);
    set_fft_size(d_fftsize);
    set_frequency_range(d_center_freq, d_bandwidth);

    if (!d_name.empty())
        set_title(d_name);

    set_output_multiple(d_fftsize);

    // initialize update time to 10 times a second
    set_update_time(0.1);
}

void freq_sink_f_impl::exec_() { d_qApplication->exec(); }

QWidget* freq_sink_f_impl::qwidget() { return d_main_gui; }

#ifdef ENABLE_PYTHON
PyObject* freq_sink_f_impl::pyqwidget()
{
    PyObject* w = PyLong_FromVoidPtr((void*)d_main_gui);
    PyObject* retarg = Py_BuildValue("N", w);
    return retarg;
}
#else
void* freq_sink_f_impl::pyqwidget() { return NULL; }
#endif

void freq_sink_f_impl::set_fft_size(const int fftsize)
{
    if ((fftsize > 16) && (fftsize < 16384))
        d_main_gui->setFFTSize(fftsize);
    else
        throw std::runtime_error("freq_sink: FFT size must be > 16 and < 16384.");
}

int freq_sink_f_impl::fft_size() const { return d_fftsize; }

void freq_sink_f_impl::set_fft_average(const float fftavg)
{
    d_main_gui->setFFTAverage(fftavg);
}

float freq_sink_f_impl::fft_average() const { return d_fftavg; }

void freq_sink_f_impl::set_fft_window(const filter::firdes::win_type win)
{
    d_main_gui->setFFTWindowType(win);
}

filter::firdes::win_type freq_sink_f_impl::fft_window() { return d_wintype; }

void freq_sink_f_impl::set_frequency_range(const double centerfreq,
                                           const double bandwidth)
{
    d_center_freq = centerfreq;
    d_bandwidth = bandwidth;
    d_main_gui->setFrequencyRange(d_center_freq, d_bandwidth);
}

void freq_sink_f_impl::set_y_axis(double min, double max)
{
    d_main_gui->setYaxis(min, max);
}

void freq_sink_f_impl::set_y_label(const std::string& label, const std::string& unit)
{
    d_main_gui->setYLabel(label, unit);
}

void freq_sink_f_impl::set_update_time(double t)
{
    // convert update time to ticks
    gr::high_res_timer_type tps = gr::high_res_timer_tps();
    d_update_time = t * tps;
    d_main_gui->setUpdateTime(t);
    d_last_time = 0;
}

void freq_sink_f_impl::set_title(const std::string& title)
{
    d_main_gui->setTitle(title.c_str());
}

void freq_sink_f_impl::set_line_label(unsigned int which, const std::string& label)
{
    d_main_gui->setLineLabel(which, label.c_str());
}

void freq_sink_f_impl::set_line_color(unsigned int which, const std::string& color)
{
    d_main_gui->setLineColor(which, color.c_str());
}

void freq_sink_f_impl::set_line_width(unsigned int which, int width)
{
    d_main_gui->setLineWidth(which, width);
}

void freq_sink_f_impl::set_line_style(unsigned int which, int style)
{
    d_main_gui->setLineStyle(which, (Qt::PenStyle)style);
}

void freq_sink_f_impl::set_line_marker(unsigned int which, int marker)
{
    d_main_gui->setLineMarker(which, (QwtSymbol::Style)marker);
}

void freq_sink_f_impl::set_line_alpha(unsigned int which, double alpha)
{
    d_main_gui->setMarkerAlpha(which, (int)(255.0 * alpha));
}

void freq_sink_f_impl::set_size(int width, int height)
{
    d_main_gui->resize(QSize(width, height));
}

void freq_sink_f_impl::set_plot_pos_half(bool half) { d_main_gui->setPlotPosHalf(half); }

void freq_sink_f_impl::set_trigger_mode(trigger_mode mode,
                                        float level,
                                        int channel,
                                        const std::string& tag_key)
{
    gr::thread::scoped_lock lock(d_setlock);

    d_trigger_mode = mode;
    d_trigger_level = level;
    d_trigger_channel = channel;
    d_trigger_tag_key = pmt::intern(tag_key);
    d_triggered = false;
    d_trigger_count = 0;

    d_main_gui->setTriggerMode(d_trigger_mode);
    d_main_gui->setTriggerLevel(d_trigger_level);
    d_main_gui->setTriggerChannel(d_trigger_channel);
    d_main_gui->setTriggerTagKey(tag_key);

    _reset();
}

std::string freq_sink_f_impl::title() { return d_main_gui->title().toStdString(); }

std::string freq_sink_f_impl::line_label(unsigned int which)
{
    return d_main_gui->lineLabel(which).toStdString();
}

std::string freq_sink_f_impl::line_color(unsigned int which)
{
    return d_main_gui->lineColor(which).toStdString();
}

int freq_sink_f_impl::line_width(unsigned int which)
{
    return d_main_gui->lineWidth(which);
}

int freq_sink_f_impl::line_style(unsigned int which)
{
    return d_main_gui->lineStyle(which);
}

int freq_sink_f_impl::line_marker(unsigned int which)
{
    return d_main_gui->lineMarker(which);
}

double freq_sink_f_impl::line_alpha(unsigned int which)
{
    return (double)(d_main_gui->markerAlpha(which)) / 255.0;
}

void freq_sink_f_impl::enable_menu(bool en) { d_main_gui->enableMenu(en); }

void freq_sink_f_impl::enable_grid(bool en) { d_main_gui->setGrid(en); }

void freq_sink_f_impl::enable_autoscale(bool en) { d_main_gui->autoScale(en); }

void freq_sink_f_impl::enable_axis_labels(bool en) { d_main_gui->setAxisLabels(en); }

void freq_sink_f_impl::enable_control_panel(bool en)
{
    if (en)
        d_main_gui->setupControlPanel();
    else
        d_main_gui->teardownControlPanel();
}

void freq_sink_f_impl::enable_max_hold(bool en) { d_main_gui->notifyMaxHold(en); }

void freq_sink_f_impl::enable_min_hold(bool en) { d_main_gui->notifyMinHold(en); }

void freq_sink_f_impl::clear_max_hold() { d_main_gui->clearMaxHold(); }

void freq_sink_f_impl::clear_min_hold() { d_main_gui->clearMinHold(); }

void freq_sink_f_impl::disable_legend() { d_main_gui->disableLegend(); }

void freq_sink_f_impl::reset()
{
    gr::thread::scoped_lock lock(d_setlock);
    _reset();
}

void freq_sink_f_impl::_reset()
{
    d_trigger_count = 0;

    // Reset the trigger.
    if (d_trigger_mode == TRIG_MODE_FREE) {
        d_triggered = true;
    } else {
        d_triggered = false;
    }
}

void freq_sink_f_impl::fft(float* data_out, const float* data_in, int size)
{
    // float to complex conversion
    gr_complex* dst = d_fft->get_inbuf();
    for (int i = 0; i < size; i++)
        dst[i] = data_in[i];

    if (!d_window.empty()) {
        volk_32fc_32f_multiply_32fc(d_fft->get_inbuf(), dst, &d_window.front(), size);
    }

    d_fft->execute(); // compute the fft
    volk_32fc_s32f_x2_power_spectral_density_32f(
        data_out, d_fft->get_outbuf(), size, 1.0, size);

    d_fft_shift.shift(data_out, size);
}

bool freq_sink_f_impl::windowreset()
{
    gr::thread::scoped_lock lock(d_setlock);

    filter::firdes::win_type newwintype;
    newwintype = d_main_gui->getFFTWindowType();
    if (d_wintype != newwintype) {
        d_wintype = newwintype;
        buildwindow();
        return true;
    }
    return false;
}

void freq_sink_f_impl::buildwindow()
{
    d_window.clear();
    if (d_wintype != filter::firdes::WIN_NONE) {
        d_window = filter::firdes::window(d_wintype, d_fftsize, 6.76);
    }
}

bool freq_sink_f_impl::fftresize()
{
    gr::thread::scoped_lock lock(d_setlock);

    int newfftsize = d_main_gui->getFFTSize();
    d_fftavg = d_main_gui->getFFTAverage();

    if (newfftsize != d_fftsize) {
        // Resize residbuf and replace data
        // +1 to handle PDU buffers
        for (int i = 0; i < d_nconnections + 1; i++) {
            volk_free(d_residbufs[i]);
            volk_free(d_magbufs[i]);

            d_residbufs[i] =
                (float*)volk_malloc(newfftsize * sizeof(float), volk_get_alignment());
            d_magbufs[i] =
                (double*)volk_malloc(newfftsize * sizeof(double), volk_get_alignment());

            memset(d_residbufs[i], 0, newfftsize * sizeof(float));
            memset(d_magbufs[i], 0, newfftsize * sizeof(double));
        }

        // Update the pointer to the newly allocated memory
        d_pdu_magbuf = d_magbufs[d_nconnections];

        // Set new fft size and reset buffer index
        // (throws away any currently held data, but who cares?)
        d_fftsize = newfftsize;
        d_index = 0;

        // Reset window to reflect new size
        buildwindow();

        // Reset FFTW plan for new size
        delete d_fft;
        d_fft = new fft::fft_complex(d_fftsize, true);

        volk_free(d_fbuf);
        d_fbuf = (float*)volk_malloc(d_fftsize * sizeof(float), volk_get_alignment());
        memset(d_fbuf, 0, d_fftsize * sizeof(float));

        d_fft_shift.resize(d_fftsize);

        d_last_time = 0;

        set_output_multiple(d_fftsize);

        return true;
    }
    return false;
}

void freq_sink_f_impl::check_clicked()
{
    if (d_main_gui->checkClicked()) {
        double freq = d_main_gui->getClickedFreq();
        message_port_pub(d_port, pmt::cons(d_port, pmt::from_double(freq)));
    }
}

void freq_sink_f_impl::handle_set_freq(pmt::pmt_t msg)
{
    if (pmt::is_pair(msg)) {
        pmt::pmt_t x = pmt::cdr(msg);
        if (pmt::is_real(x)) {
            d_center_freq = pmt::to_double(x);
            d_qApplication->postEvent(d_main_gui,
                                      new SetFreqEvent(d_center_freq, d_bandwidth));
        }
    }
}

void freq_sink_f_impl::handle_set_bw(pmt::pmt_t msg)
{
    if (pmt::is_pair(msg)) {
        pmt::pmt_t x = pmt::cdr(msg);
        if (pmt::is_real(x)) {
            d_bandwidth = pmt::to_double(x);
            d_qApplication->postEvent(d_main_gui,
                                      new SetFreqEvent(d_center_freq, d_bandwidth));
        }
    }
}

void freq_sink_f_impl::_gui_update_trigger()
{
    trigger_mode new_trigger_mode = d_main_gui->getTriggerMode();
    d_trigger_level = d_main_gui->getTriggerLevel();
    d_trigger_channel = d_main_gui->getTriggerChannel();

    std::string tagkey = d_main_gui->getTriggerTagKey();
    d_trigger_tag_key = pmt::intern(tagkey);

    if (new_trigger_mode != d_trigger_mode) {
        d_trigger_mode = new_trigger_mode;
        _reset();
    }
}

void freq_sink_f_impl::_test_trigger_tags(int start, int nitems)
{
    uint64_t nr = nitems_read(d_trigger_channel);
    std::vector<gr::tag_t> tags;
    get_tags_in_range(
        tags, d_trigger_channel, nr + start, nr + start + nitems, d_trigger_tag_key);
    if (!tags.empty()) {
        d_triggered = true;
        d_index = tags[0].offset - nr;
        d_trigger_count = 0;
    }
}

void freq_sink_f_impl::_test_trigger_norm(int nitems, std::vector<double*> inputs)
{
    const double* in = (const double*)inputs[d_trigger_channel];
    for (int i = 0; i < nitems; i++) {
        d_trigger_count++;

        // Test if trigger has occurred based on the FFT magnitude and
        // channel number. Test if any value is > the level (in dBx).
        if (in[i] > d_trigger_level) {
            d_triggered = true;
            d_trigger_count = 0;
            break;
        }
    }

    // If using auto trigger mode, trigger periodically even
    // without a trigger event.
    if ((d_trigger_mode == TRIG_MODE_AUTO) && (d_trigger_count > d_fftsize)) {
        d_triggered = true;
        d_trigger_count = 0;
    }
}

int freq_sink_f_impl::work(int noutput_items,
                           gr_vector_const_void_star& input_items,
                           gr_vector_void_star& output_items)
{
    const float* in = (const float*)input_items[0];

    // Update the FFT size from the application
    bool updated = false;
    updated |= fftresize();
    updated |= windowreset();
    if (updated)
        return 0;

    check_clicked();
    _gui_update_trigger();

    gr::thread::scoped_lock lock(d_setlock);
    for (d_index = 0; d_index < noutput_items; d_index += d_fftsize) {

        if ((gr::high_res_timer_now() - d_last_time) > d_update_time) {

            // Trigger off tag, if active
            if ((d_trigger_mode == TRIG_MODE_TAG) && !d_triggered) {
                _test_trigger_tags(d_index, d_fftsize);
                if (d_triggered) {
                    // If not enough from tag position, early exit
                    if ((d_index + d_fftsize) >= noutput_items)
                        return d_index;
                }
            }

            for (int n = 0; n < d_nconnections; n++) {
                // Fill up residbuf with d_fftsize number of items
                in = (const float*)input_items[n];
                memcpy(d_residbufs[n], &in[d_index], sizeof(float) * d_fftsize);

                fft(d_fbuf, d_residbufs[n], d_fftsize);
                for (int x = 0; x < d_fftsize; x++) {
                    d_magbufs[n][x] = (double)((1.0 - d_fftavg) * d_magbufs[n][x] +
                                               (d_fftavg)*d_fbuf[x]);
                }
                // volk_32f_convert_64f(d_magbufs[n], d_fbuf, d_fftsize);
            }

            // Test trigger off signal power in d_magbufs
            if ((d_trigger_mode == TRIG_MODE_NORM) ||
                (d_trigger_mode == TRIG_MODE_AUTO)) {
                _test_trigger_norm(d_fftsize, d_magbufs);
            }

            // If a trigger (FREE always triggers), plot and reset state
            if (d_triggered) {
                d_last_time = gr::high_res_timer_now();
                d_qApplication->postEvent(d_main_gui,
                                          new FreqUpdateEvent(d_magbufs, d_fftsize));
                _reset();
            }
        }
    }

    return noutput_items;
}

void freq_sink_f_impl::handle_pdus(pmt::pmt_t msg)
{
    size_t len;
    pmt::pmt_t dict, samples;

    // Test to make sure this is either a PDU or a uniform vector of
    // samples. Get the samples PMT and the dictionary if it's a PDU.
    // If not, we throw an error and exit.
    if (pmt::is_pair(msg)) {
        dict = pmt::car(msg);
        samples = pmt::cdr(msg);
    } else if (pmt::is_uniform_vector(msg)) {
        samples = msg;
    } else {
        throw std::runtime_error("time_sink_c: message must be either "
                                 "a PDU or a uniform vector of samples.");
    }

    len = pmt::length(samples);

    const float* in;
    if (pmt::is_f32vector(samples)) {
        in = (const float*)pmt::f32vector_elements(samples, len);
    } else {
        throw std::runtime_error("freq_sink_f: unknown data type "
                                 "of samples; must be float.");
    }

    // Plot if we're past the last update time
    if (gr::high_res_timer_now() - d_last_time > d_update_time) {
        d_last_time = gr::high_res_timer_now();

        // Update the FFT size from the application
        fftresize();
        windowreset();
        check_clicked();

        int winoverlap = 4;
        int fftoverlap = d_fftsize / winoverlap;
        float num = static_cast<float>(winoverlap * len) / static_cast<float>(d_fftsize);
        int nffts = static_cast<int>(ceilf(num));

        // Clear this as we will be accumulating in the for loop over nffts
        memset(d_pdu_magbuf, 0, sizeof(double) * d_fftsize);

        size_t min = 0;
        size_t max = std::min(d_fftsize, static_cast<int>(len));
        for (int n = 0; n < nffts; n++) {
            // Clear in case (max-min) < d_fftsize
            memset(d_residbufs[d_nconnections], 0x00, sizeof(float) * d_fftsize);

            // Copy in as much of the input samples as we can
            memcpy(d_residbufs[d_nconnections], &in[min], sizeof(float) * (max - min));

            // Apply the window and FFT; copy data into the PDU
            // magnitude buffer.
            fft(d_fbuf, d_residbufs[d_nconnections], d_fftsize);
            for (int x = 0; x < d_fftsize; x++) {
                d_pdu_magbuf[x] += (double)d_fbuf[x];
            }

            // Increment our indices; set max up to the number of
            // samples in the input PDU.
            min += fftoverlap;
            max = std::min(max + fftoverlap, len);
        }

        // Perform the averaging
        for (int x = 0; x < d_fftsize; x++) {
            d_pdu_magbuf[x] /= static_cast<double>(nffts);
        }

        // update gui per-pdu
        d_qApplication->postEvent(d_main_gui, new FreqUpdateEvent(d_magbufs, d_fftsize));
    }
}

} /* namespace qtgui */
} /* namespace gr */