/*!
 * \file galileo_e1_pcps_ambiguous_acquisition.cc
 * \brief Adapts a PCPS acquisition block to an AcquisitionInterface for
 *  Galileo E1 Signals
 * \author Luis Esteve, 2012. luis(at)epsilon-formacion.com
 *
 * -------------------------------------------------------------------------
 *
 * Copyright (C) 2010-2011  (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 <http://www.gnu.org/licenses/>.
 *
 * -------------------------------------------------------------------------
 */

#include "galileo_e1_pcps_ambiguous_acquisition.h"
#include "galileo_e1_signal_processing.h"
#include "Galileo_E1.h"
#include "configuration_interface.h"
#include <iostream>
#include <string>
#include <boost/lexical_cast.hpp>
#include <glog/log_severity.h>
#include <glog/logging.h>
#include <boost/math/distributions/exponential.hpp>

using google::LogMessage;

GalileoE1PcpsAmbiguousAcquisition::GalileoE1PcpsAmbiguousAcquisition(
        ConfigurationInterface* configuration, std::string role,
        unsigned int in_streams, unsigned int out_streams,
        boost::shared_ptr<gr::msg_queue> queue) :
        role_(role), in_streams_(in_streams), out_streams_(out_streams), queue_(queue)
{
    configuration_ = configuration;
    std::string default_item_type = "gr_complex";
    std::string default_dump_filename = "../data/acquisition.dat";

    DLOG(INFO) << "role " << role;

    item_type_ = configuration_->property(role + ".item_type",
            default_item_type);

    fs_in_ = configuration_->property("GNSS-SDR.internal_fs_hz", 4000000);
    if_ = configuration_->property(role + ".ifreq", 0);
    dump_ = configuration_->property(role + ".dump", false);
    shift_resolution_ = configuration_->property(role + ".doppler_max", 15);
    sampled_ms_ = configuration_->property(role + ".sampled_ms", 4);
    dump_filename_ = configuration_->property(role + ".dump_filename",
            default_dump_filename);

    //--- Find number of samples per spreading code (4 ms)  -----------------

    vector_length_ = round(
            fs_in_
            / (Galileo_E1_CODE_CHIP_RATE_HZ
                    / Galileo_E1_B_CODE_LENGTH_CHIPS));

    int samples_per_ms = vector_length_ / 4;

    vector_length_ = samples_per_ms * 4;

    code_ = new gr_complex[samples_per_ms*sampled_ms_];

    if (item_type_.compare("gr_complex") == 0)
        {
            item_size_ = sizeof(gr_complex);
            acquisition_cc_ = pcps_make_acquisition_cc(sampled_ms_,
                    shift_resolution_, if_, fs_in_, samples_per_ms, vector_length_,
                    queue_, dump_, dump_filename_);
            stream_to_vector_ = gr::blocks::stream_to_vector::make(item_size_, samples_per_ms * sampled_ms_);
            DLOG(INFO) << "stream_to_vector("
                    << stream_to_vector_->unique_id() << ")";
            DLOG(INFO) << "acquisition(" << acquisition_cc_->unique_id()
                    << ")";
        }
    else
        {
            LOG_AT_LEVEL(WARNING) << item_type_
                    << " unknown acquisition item type";
        }
}


GalileoE1PcpsAmbiguousAcquisition::~GalileoE1PcpsAmbiguousAcquisition()
{
    delete[] code_;
}


void
GalileoE1PcpsAmbiguousAcquisition::set_channel(unsigned int channel)
{
    channel_ = channel;
    if (item_type_.compare("gr_complex") == 0)
        {
            acquisition_cc_->set_channel(channel_);
        }
}


void
GalileoE1PcpsAmbiguousAcquisition::set_threshold(float threshold)
{

	float pfa = configuration_->property(role_+ boost::lexical_cast<std::string>(channel_) + ".pfa", 0.0);

	if(pfa==0.0) pfa = configuration_->property(role_+".pfa", 0.0);

	if(pfa==0.0)
	{
		threshold_ = threshold;
	}
	else
    {
		threshold_ = calculate_threshold(pfa);
	}

	DLOG(INFO) <<"Channel "<<channel_<<" Threshold = " << threshold_;

	if (item_type_.compare("gr_complex") == 0)
        {
            acquisition_cc_->set_threshold(threshold_);
        }
}


void
GalileoE1PcpsAmbiguousAcquisition::set_doppler_max(unsigned int doppler_max)
{
    doppler_max_ = doppler_max;

    if (item_type_.compare("gr_complex") == 0)
        {
            acquisition_cc_->set_doppler_max(doppler_max_);
        }

}


void
GalileoE1PcpsAmbiguousAcquisition::set_doppler_step(unsigned int doppler_step)
{
    doppler_step_ = doppler_step;
    if (item_type_.compare("gr_complex") == 0)
        {
            acquisition_cc_->set_doppler_step(doppler_step_);
        }

}


void
GalileoE1PcpsAmbiguousAcquisition::set_channel_queue(
        concurrent_queue<int> *channel_internal_queue)
{
    channel_internal_queue_ = channel_internal_queue;
    if (item_type_.compare("gr_complex") == 0)
        {
            acquisition_cc_->set_channel_queue(channel_internal_queue_);
        }
}


void
GalileoE1PcpsAmbiguousAcquisition::set_gnss_synchro(
        Gnss_Synchro* gnss_synchro)
{
    gnss_synchro_ = gnss_synchro;
    if (item_type_.compare("gr_complex") == 0)
        {
            acquisition_cc_->set_gnss_synchro(gnss_synchro_);
        }
}


signed int
GalileoE1PcpsAmbiguousAcquisition::mag()
{
    if (item_type_.compare("gr_complex") == 0)
        {
            return acquisition_cc_->mag();
        }
    else
        {
            return 0;
        }
}


void
GalileoE1PcpsAmbiguousAcquisition::init()
{
    acquisition_cc_->init();
    set_local_code();
}

void
GalileoE1PcpsAmbiguousAcquisition::set_local_code()
{
    if (item_type_.compare("gr_complex") == 0)
        {
            bool cboc = configuration_->property(
                    "Acquisition" + boost::lexical_cast<std::string>(channel_)
                            + ".cboc", false);

            std::complex<float> * code = new std::complex<float>[vector_length_];

            galileo_e1_code_gen_complex_sampled(code, gnss_synchro_->Signal,
                    cboc, gnss_synchro_->PRN, fs_in_, 0, false);

            for (unsigned int i = 0; i < sampled_ms_/4; i++)
                {
                    memcpy(&(code_[i*vector_length_]), code,
                           sizeof(gr_complex)*vector_length_);
                }

            acquisition_cc_->set_local_code(code_);
        }
}


void
GalileoE1PcpsAmbiguousAcquisition::reset()
{
    if (item_type_.compare("gr_complex") == 0)
        {
            acquisition_cc_->set_active(true);
        }
}

float GalileoE1PcpsAmbiguousAcquisition::calculate_threshold(float pfa)
{
	unsigned int frequency_bins = 0;
	for (int doppler = (int)(-doppler_max_); doppler <= (int)doppler_max_; doppler += doppler_step_)
	{
	 	frequency_bins++;
	}

	DLOG(INFO) <<"Channel "<<channel_<<"  Pfa = "<< pfa;

	unsigned int ncells = vector_length_*frequency_bins;
	double exponent = 1/(double)ncells;
	double val = pow(1.0-pfa,exponent);
	double lambda = double(vector_length_);
	boost::math::exponential_distribution<double> mydist (lambda);
	float threshold = (float)quantile(mydist,val);

	return threshold;
}


void
GalileoE1PcpsAmbiguousAcquisition::connect(gr::top_block_sptr top_block)
{
    if (item_type_.compare("gr_complex") == 0)
        {
            top_block->connect(stream_to_vector_, 0, acquisition_cc_, 0);
        }

}



void
GalileoE1PcpsAmbiguousAcquisition::disconnect(gr::top_block_sptr top_block)
{
    if (item_type_.compare("gr_complex") == 0)
        {
            top_block->disconnect(stream_to_vector_, 0, acquisition_cc_, 0);
        }
}



gr::basic_block_sptr GalileoE1PcpsAmbiguousAcquisition::get_left_block()
{
    return stream_to_vector_;
}



gr::basic_block_sptr GalileoE1PcpsAmbiguousAcquisition::get_right_block()
{
    return acquisition_cc_;
}