/*  anf.c

This file is part of a program that implements a Software-Defined Radio.

Copyright (C) 2012, 2013 Warren Pratt, NR0V

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 2
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, write to the Free Software
Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

The author can be reached by email at

warren@wpratt.com

*/

#include "comm.h"

ANF create_anf  (
                int run,
                int position,
                int buff_size,
                double *in_buff,
                double *out_buff,
                int dline_size,
                int n_taps,
                int delay,
                double two_mu,
                double gamma,

                double lidx,
                double lidx_min,
                double lidx_max,
                double ngamma,
                double den_mult,
                double lincr,
                double ldecr
            )
{
    ANF a = (ANF) malloc0 (sizeof(anf));
    a->run = run;
    a->position = position;
    a->buff_size = buff_size;
    a->in_buff = in_buff;
    a->out_buff = out_buff;
    a->dline_size = dline_size;
    a->mask = dline_size - 1;
    a->n_taps = n_taps;
    a->delay = delay;
    a->two_mu = two_mu;
    a->gamma = gamma;
    a->in_idx = 0;
    a->lidx = lidx;
    a->lidx_min = lidx_min;
    a->lidx_max = lidx_max;
    a->ngamma = ngamma;
    a->den_mult = den_mult;
    a->lincr = lincr;
    a->ldecr = ldecr;

    memset (a->d, 0, sizeof(double) * ANF_DLINE_SIZE);
    memset (a->w, 0, sizeof(double) * ANF_DLINE_SIZE);

    return a;
}

void destroy_anf (ANF a)
{
    _aligned_free (a);
}

void xanf(ANF a, int position)
{
    int i, j, idx;
    double c0, c1;
    double y, error, sigma, inv_sigp;
    double nel, nev;
    if (a->run && (a->position == position))
    {
        for (i = 0; i < a->buff_size; i++)
        {
            a->d[a->in_idx] = a->in_buff[2 * i + 0];

            y = 0;
            sigma = 0;

            for (j = 0; j < a->n_taps; j++)
            {
                idx = (a->in_idx + j + a->delay) & a->mask;
                y += a->w[j] * a->d[idx];
                sigma += a->d[idx] * a->d[idx];
            }
            inv_sigp = 1.0 / (sigma + 1e-10);
            error = a->d[a->in_idx] - y;

            a->out_buff[2 * i + 0] = error;
            a->out_buff[2 * i + 1] = 0.0;

            if((nel = error * (1.0 - a->two_mu * sigma * inv_sigp)) < 0.0) nel = -nel;
            if((nev = a->d[a->in_idx] - (1.0 - a->two_mu * a->ngamma) * y - a->two_mu * error * sigma * inv_sigp) < 0.0) nev = -nev;
            if (nev < nel)
            {
                if ((a->lidx += a->lincr) > a->lidx_max) a->lidx = a->lidx_max;
            }
            else
            {
                if ((a->lidx -= a->ldecr) < a->lidx_min) a->lidx = a->lidx_min;
            }
            a->ngamma = a->gamma * (a->lidx * a->lidx) * (a->lidx * a->lidx) * a->den_mult;

            c0 = 1.0 - a->two_mu * a->ngamma;
            c1 = a->two_mu * error * inv_sigp;

            for (j = 0; j < a->n_taps; j++)
            {
                idx = (a->in_idx + j + a->delay) & a->mask;
                a->w[j] = c0 * a->w[j] + c1 * a->d[idx];
            }
            a->in_idx = (a->in_idx + a->mask) & a->mask;
        }
    }
    else if (a->in_buff != a->out_buff)
        memcpy (a->out_buff, a->in_buff, a->buff_size * sizeof (complex));
}

void flush_anf (ANF a)
{
    memset (a->d, 0, sizeof(double) * ANF_DLINE_SIZE);
    memset (a->w, 0, sizeof(double) * ANF_DLINE_SIZE);
    a->in_idx = 0;
}

void setBuffers_anf (ANF a, double* in, double* out)
{
    a->in_buff = in;
    a->out_buff = out;
}

void setSamplerate_anf (ANF a, int rate)
{
    flush_anf (a);
}

void setSize_anf (ANF a, int size)
{
    a->buff_size = size;
    flush_anf (a);
}

/********************************************************************************************************
*                                                                                                       *
*                                           RXA Properties                                              *
*                                                                                                       *
********************************************************************************************************/

PORT void
SetRXAANFRun (int channel, int run)
{
    ANF a = rxa[channel].anf.p;
    if (a->run != run)
    {
        RXAbp1Check (channel, rxa[channel].amd.p->run, rxa[channel].snba.p->run,
            rxa[channel].emnr.p->run, run, rxa[channel].anr.p->run);
        EnterCriticalSection (&ch[channel].csDSP);
        a->run = run;
        RXAbp1Set (channel);
        flush_anf (a);
        LeaveCriticalSection (&ch[channel].csDSP);
    }
}


PORT void
SetRXAANFVals (int channel, int taps, int delay, double gain, double leakage)
{
    EnterCriticalSection (&ch[channel].csDSP);
    rxa[channel].anf.p->n_taps = taps;
    rxa[channel].anf.p->delay = delay;
    rxa[channel].anf.p->two_mu = gain;          //try two_mu = 1e-4
    rxa[channel].anf.p->gamma = leakage;        //try gamma = 0.10
    flush_anf (rxa[channel].anf.p);
    LeaveCriticalSection (&ch[channel].csDSP);
}

PORT void
SetRXAANFTaps (int channel, int taps)
{
    EnterCriticalSection (&ch[channel].csDSP);
    rxa[channel].anf.p->n_taps = taps;
    flush_anf (rxa[channel].anf.p);
    LeaveCriticalSection (&ch[channel].csDSP);
}

PORT void
SetRXAANFDelay (int channel, int delay)
{
    EnterCriticalSection (&ch[channel].csDSP);
    rxa[channel].anf.p->delay = delay;
    flush_anf (rxa[channel].anf.p);
    LeaveCriticalSection (&ch[channel].csDSP);
}

PORT void
SetRXAANFGain (int channel, double gain)
{
    EnterCriticalSection (&ch[channel].csDSP);
    rxa[channel].anf.p->two_mu = gain;
    flush_anf (rxa[channel].anf.p);
    LeaveCriticalSection (&ch[channel].csDSP);
}

PORT void
SetRXAANFLeakage (int channel, double leakage)
{
    EnterCriticalSection (&ch[channel].csDSP);
    rxa[channel].anf.p->gamma = leakage;
    flush_anf (rxa[channel].anf.p);
    LeaveCriticalSection (&ch[channel].csDSP);
}

PORT void
SetRXAANFPosition (int channel, int position)
{
    EnterCriticalSection (&ch[channel].csDSP);
    rxa[channel].anf.p->position = position;
    rxa[channel].bp1.p->position = position;
    flush_anf (rxa[channel].anf.p);
    LeaveCriticalSection (&ch[channel].csDSP);
}
