/*	nobII.c

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

Copyright (C) 2014 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"

#define MAX_ADV_SLEW_TIME			(0.002)
#define MAX_ADV_TIME				(0.002)
#define MAX_HANG_SLEW_TIME			(0.002)
#define MAX_HANG_TIME				(0.002)
#define MAX_SEQ_TIME				(0.025)
#define MAX_SAMPLERATE				(1536000.0)

void init_nob (NOB a)
{
	int i;
	double coef;
	a->adv_slew_count = (int)(a->advslewtime * a->samplerate);
	a->adv_count = (int)(a->advtime * a->samplerate);
	a->hang_count = (int)(a->hangtime * a->samplerate);
	a->hang_slew_count = (int)(a->hangslewtime * a->samplerate);
	a->max_imp_seq = (int)(a->max_imp_seq_time * a->samplerate);
	a->backmult = exp (-1.0 / (a->samplerate * a->backtau));
	a->ombackmult = 1.0 - a->backmult;
	if (a->adv_slew_count > 0)
	{
		coef = PI / (a->adv_slew_count + 1);
		for (i = 0; i < a->adv_slew_count; i++)
			a->awave[i] = 0.5 * cos ((i + 1) * coef);
	}
	if (a->hang_slew_count > 0)
	{
		coef = PI / a->hang_slew_count;
		for (i = 0; i < a->hang_slew_count; i++)
			a->hwave[i] = 0.5 * cos (i * coef);
	}
	
	flush_nob (a);
}

PORT
NOB create_nob (
	int run,
	int buffsize,
	double* in,
	double* out,
	double samplerate,
	int mode,
	double advslewtime,
	double advtime,
	double hangslewtime,
	double hangtime,
	double max_imp_seq_time,
	double backtau,
	double threshold
	)
{
	NOB a = (NOB) malloc0 (sizeof (nob));
	a->run = run;
	a->buffsize = buffsize;
	a->in = in;
	a->out = out;
	a->samplerate = samplerate;
	a->mode = mode;
	a->advslewtime = advslewtime;
	a->advtime = advtime;
	a->hangslewtime = hangslewtime;
	a->hangtime = hangtime;
	a->max_imp_seq_time = max_imp_seq_time;
	a->backtau = backtau;
	a->threshold = threshold;
	a->dline_size = (int)(MAX_SAMPLERATE * (MAX_ADV_SLEW_TIME +
											MAX_ADV_TIME +
											MAX_HANG_SLEW_TIME +
											MAX_HANG_TIME +
											MAX_SEQ_TIME ) + 2);
	a->dline = (double *)malloc0 (a->dline_size * sizeof (complex));
	a->imp = (int *)malloc0 (a->dline_size * sizeof (int));
	a->awave = (double *)malloc0 ((int)(MAX_ADV_SLEW_TIME  * MAX_SAMPLERATE + 1) * sizeof (double));
	a->hwave = (double *)malloc0 ((int)(MAX_HANG_SLEW_TIME * MAX_SAMPLERATE + 1) * sizeof (double));

	a->filterlen = 10;
	a->bfbuff = (double *)malloc0 (a->filterlen * sizeof (complex));
	a->ffbuff = (double *)malloc0 (a->filterlen * sizeof (complex));
	a->fcoefs = (double *)malloc0 (a->filterlen * sizeof (double));
	a->fcoefs[0] = 0.308720593;
	a->fcoefs[1] = 0.216104415;
	a->fcoefs[2] = 0.151273090;
	a->fcoefs[3] = 0.105891163;
	a->fcoefs[4] = 0.074123814;
	a->fcoefs[5] = 0.051886670;
	a->fcoefs[6] = 0.036320669;
	a->fcoefs[7] = 0.025424468;
	a->fcoefs[8] = 0.017797128;
	a->fcoefs[9] = 0.012457989;

	InitializeCriticalSectionAndSpinCount (&a->cs_update, 2500);
	init_nob (a);

	a->legacy = (double *) malloc0 (2048 * sizeof (complex));														/////////////// legacy interface - remove
	return a;
}

PORT
void destroy_nob (NOB a)
{
	_aligned_free (a->legacy);																					   ///////////////	remove
	_aligned_free (a->fcoefs);
	_aligned_free (a->ffbuff);
	_aligned_free (a->bfbuff);
	_aligned_free (a->hwave);
	_aligned_free (a->awave);
	_aligned_free (a->imp);
	_aligned_free (a->dline);
	_aligned_free (a);
}

PORT
void flush_nob (NOB a)
{
	a->out_idx = 0;
	a->scan_idx = a->out_idx + a->adv_slew_count + a->adv_count + 1;
	a->in_idx = a->scan_idx + a->max_imp_seq + a->hang_count + a->hang_slew_count + a->filterlen;
	a->state = 0;
	a->overflow = 0;
	a->avg = 1.0;
	a->bfb_in_idx = a->filterlen - 1;
	a->ffb_in_idx = a->filterlen - 1;
	memset (a->dline, 0, a->dline_size * sizeof (complex));
	memset (a->imp, 0, a->dline_size * sizeof (int));
	memset (a->bfbuff, 0, a->filterlen * sizeof (complex));
	memset (a->ffbuff, 0, a->filterlen * sizeof (complex));
}

PORT
void xnob (NOB a)
{
	double scale;
	double mag;
	int bf_idx;
	int ff_idx;
	int lidx, tidx;
	int i, j, k;
	int bfboutidx;
	int ffboutidx;
	int hcount;
	int len;
	int ffcount;
	int staydown;
	EnterCriticalSection (&a->cs_update);
	if (a->run)
	{
		for (i = 0; i < a->buffsize; i++)
		{
			a->dline[2 * a->in_idx + 0] = a->in[2 * i + 0];
			a->dline[2 * a->in_idx + 1] = a->in[2 * i + 1];
			mag = sqrt(a->dline[2 * a->in_idx + 0] * a->dline[2 * a->in_idx + 0] + a->dline[2 * a->in_idx + 1] * a->dline[2 * a->in_idx + 1]);
			a->avg = a->backmult * a->avg + a->ombackmult * mag;
			if (mag > (a->avg * a->threshold))
				a->imp[a->in_idx] = 1;
			else
				a->imp[a->in_idx] = 0;
			if ((bf_idx = a->out_idx + a->adv_slew_count) >= a->dline_size) bf_idx -= a->dline_size;
			if (a->imp[bf_idx] == 0)
			{
				if (++a->bfb_in_idx == a->filterlen) a->bfb_in_idx -= a->filterlen;
				a->bfbuff[2 * a->bfb_in_idx + 0] = a->dline[2 * bf_idx + 0];
				a->bfbuff[2 * a->bfb_in_idx + 1] = a->dline[2 * bf_idx + 1];
			}

			switch (a->state)
			{
				case 0:		// normal output & impulse setup
					{
						a->out[2 * i + 0] = a->dline[2 * a->out_idx + 0];
						a->out[2 * i + 1] = a->dline[2 * a->out_idx + 1];
						a->Ilast = a->dline[2 * a->out_idx + 0];
						a->Qlast = a->dline[2 * a->out_idx + 1];	
						if (a->imp[a->scan_idx] > 0)
						{
							a->time = 0;
							if (a->adv_slew_count > 0)
								a->state = 1;
							else if (a->adv_count > 0)
								a->state = 2;
							else
								a->state = 3;
							tidx = a->scan_idx;
							a->blank_count = 0;
							do
							{
								hcount = 0;
								while ((a->imp[tidx] > 0 || hcount > 0) && a->blank_count < a->max_imp_seq)
								{
									a->blank_count++;
									if (hcount > 0) hcount--;
									if (a->imp[tidx] > 0) hcount = a->hang_count + a->hang_slew_count;
									if (++tidx >= a->dline_size) tidx -= a->dline_size;
								}
								j = 1;
								len = 0;
								lidx = tidx;
								while (j <= a->adv_slew_count + a->adv_count && len == 0)
								{
									if (a->imp[lidx] == 1)
									{
										len = j;
										tidx = lidx;
									}
									if (++lidx >= a->dline_size) lidx -= a->dline_size;
									j++;
								}
								if((a->blank_count += len) > a->max_imp_seq)
								{
									a->blank_count = a->max_imp_seq;
									a->overflow = 1;
									break;
								}
							} while (len != 0);
							if (a->overflow == 0)
							{
								a->blank_count -= a->hang_slew_count;
								a->Inext = a->dline[2 * tidx + 0];
								a->Qnext = a->dline[2 * tidx + 1];
								
								if (a->mode == 1 || a->mode == 2 || a->mode == 4)
								{
									bfboutidx = a->bfb_in_idx;
									a->I1 = 0.0;
									a->Q1 = 0.0;
									for (k = 0; k < a->filterlen; k++)
									{
										a->I1 += a->fcoefs[k] * a->bfbuff[2 * bfboutidx + 0];
										a->Q1 += a->fcoefs[k] * a->bfbuff[2 * bfboutidx + 1];
										if (--bfboutidx < 0) bfboutidx += a->filterlen;
									}
								}

								if (a->mode == 2 || a->mode == 3 || a->mode == 4)
								{
									if ((ff_idx = a->scan_idx + a->blank_count) >= a->dline_size) ff_idx -= a->dline_size;
									ffcount = 0;
									while (ffcount < a->filterlen)
									{
										if (a->imp[ff_idx] == 0)
										{
											if (++a->ffb_in_idx == a->filterlen) a->ffb_in_idx -= a->filterlen;
											a->ffbuff[2 * a->ffb_in_idx + 0] = a->dline[2 * ff_idx + 0];
											a->ffbuff[2 * a->ffb_in_idx + 1] = a->dline[2 * ff_idx + 1];
											++ffcount;
										}
										if (++ff_idx >= a->dline_size) ff_idx -= a->dline_size;
									}
									if ((ffboutidx = a->ffb_in_idx + 1) >= a->filterlen) ffboutidx -= a->filterlen;
									a->I2 = 0.0;
									a->Q2 = 0.0;
									for (k = 0; k < a->filterlen; k++)
									{
										a->I2 += a->fcoefs[k] * a->ffbuff[2 * ffboutidx + 0];
										a->Q2 += a->fcoefs[k] * a->ffbuff[2 * ffboutidx + 1];
										if (++ffboutidx >= a->filterlen) ffboutidx -= a->filterlen;
									}
								}

								switch (a->mode)
								{
									case 0: // zero
										a->deltaI = 0.0;
										a->deltaQ = 0.0;
										a->I = 0.0;
										a->Q = 0.0;
										break;
									case 1: // sample-hold
										a->deltaI = 0.0;
										a->deltaQ = 0.0;
										a->I = a->I1;
										a->Q = a->Q1;
										break;
									case 2: // mean-hold
										a->deltaI = 0.0;
										a->deltaQ = 0.0;
										a->I = 0.5 * (a->I1 + a->I2);
										a->Q = 0.5 * (a->Q1 + a->Q2);
										break;
									case 3: // hold-sample
										a->deltaI = 0.0;
										a->deltaQ = 0.0;
										a->I = a->I2;
										a->Q = a->Q2;
										break;
									case 4: // linear interpolation
										a->deltaI = (a->I2 - a->I1) / (a->adv_count + a->blank_count);
										a->deltaQ = (a->Q2 - a->Q1) / (a->adv_count + a->blank_count);
										a->I = a->I1;
										a->Q = a->Q1;
										break;
								}
							}
							else
							{
								if (a->adv_slew_count > 0)
									a->state = 5;
								else
								{
									a->state = 6;
									a->time = 0;
									a->blank_count += a->adv_count + a->filterlen;
								}
							}
						}
						break;
					}
				case 1:		// slew output in advance of blanking period
					{
						scale = 0.5 + a->awave[a->time];
						a->out[2 * i + 0] = a->Ilast * scale + (1.0 - scale) * a->I;
						a->out[2 * i + 1] = a->Qlast * scale + (1.0 - scale) * a->Q;
						if (++a->time == a->adv_slew_count)
						{
							a->time = 0;
							if (a->adv_count > 0)
								a->state = 2;
							else
								a->state = 3;
						}
						break;
					}
				case 2:		// initial advance period
					{
						a->out[2 * i + 0] = a->I;
						a->out[2 * i + 1] = a->Q;
						a->I += a->deltaI;
						a->Q += a->deltaQ;

						if (++a->time == a->adv_count)
						{
							a->state = 3;
							a->time = 0;
						}
						break;
					}
				case 3:		// impulse & hang period
					{
						a->out[2 * i + 0] = a->I;
						a->out[2 * i + 1] = a->Q;
						a->I += a->deltaI;
						a->Q += a->deltaQ;

						if (++a->time == a->blank_count)
						{
							if (a->hang_slew_count > 0)
							{
								a->state = 4;
								a->time = 0;
							}
							else
								a->state = 0;
						}
						break;
					}
				case 4:		// slew output after blanking period
					{
						scale = 0.5 - a->hwave[a->time];
						a->out[2 * i + 0] = a->Inext * scale + (1.0 - scale) * a->I;
						a->out[2 * i + 1] = a->Qnext * scale + (1.0 - scale) * a->Q;
						if (++a->time == a->hang_slew_count)
							a->state = 0;
						break;
					}
				case 5:
					{
						scale = 0.5 + a->awave[a->time];
						a->out[2 * i + 0] = a->Ilast * scale;
						a->out[2 * i + 1] = a->Qlast * scale;
						if (++a->time == a->adv_slew_count)
						{
							a->state = 6;
							a->time = 0;
							a->blank_count += a->adv_count + a->filterlen;
						}
						break;
					}
				case 6:
					{
						a->out[2 * i + 0] = 0.0;
						a->out[2 * i + 1] = 0.0;
						if (++a->time == a->blank_count)
							a->state = 7;
						break;
					}
				case 7:
					{
						a->out[2 * i + 0] = 0.0;
						a->out[2 * i + 1] = 0.0;
						staydown = 0;
						a->time = 0;
						if ((tidx = a->scan_idx + a->hang_slew_count + a->hang_count) >= a->dline_size) tidx -= a->dline_size;
						while (a->time++ <= a->adv_count + a->adv_slew_count + a->hang_slew_count + a->hang_count)																			  //  CHECK EXACT COUNTS!!!!!!!!!!!!!!!!!!!!!!!
						{
							if (a->imp[tidx] == 1) staydown = 1;
							if (--tidx < 0) tidx += a->dline_size;
						}
						if (staydown == 0)
						{
							if (a->hang_count > 0)
							{
								a->state = 8;
								a->time = 0;
							}
							else if (a->hang_slew_count > 0)
							{
								a->state = 9;
								a->time = 0;
								if ((tidx = a->scan_idx + a->hang_slew_count + a->hang_count - a->adv_count - a->adv_slew_count) >= a->dline_size) tidx -= a->dline_size;
								if (tidx < 0) tidx += a->dline_size;
								a->Inext = a->dline[2 * tidx + 0];
								a->Qnext = a->dline[2 * tidx + 1];
							}
							else
							{
								a->state = 0;
								a->overflow = 0;
							}
						}
						break;
					}
				case 8:
					{
						a->out[2 * i + 0] = 0.0;
						a->out[2 * i + 1] = 0.0;
						if (++a->time == a->hang_count)
						{
							if (a->hang_slew_count > 0)
							{
								a->state = 9;
								a->time = 0;
								if ((tidx = a->scan_idx + a->hang_slew_count - a->adv_count - a->adv_slew_count) >= a->dline_size) tidx -= a->dline_size;
								if (tidx < 0) tidx += a->dline_size;
								a->Inext = a->dline[2 * tidx + 0];
								a->Qnext = a->dline[2 * tidx + 1];
							}
							else
							{
								a->state = 0;
								a->overflow = 0;
							}
						}
						break;
					}
				case 9:
					{
						scale = 0.5 - a->hwave[a->time];
						a->out[2 * i + 0] = a->Inext * scale;
						a->out[2 * i + 1] = a->Qnext * scale;

						if (++a->time >= a->hang_slew_count)
						{
							a->state = 0;
							a->overflow = 0;
						}
						break;
					}
			}
			if (++a->in_idx == a->dline_size) a->in_idx = 0;
			if (++a->scan_idx == a->dline_size) a->scan_idx = 0;
			if (++a->out_idx == a->dline_size) a->out_idx = 0;
		}
	}
	else if (a->in != a->out)
		memcpy (a->out, a->in, a->buffsize * sizeof (complex));
	LeaveCriticalSection (&a->cs_update);
}

void setBuffers_nob (NOB a, double* in, double* out)
{
	a->in = in;
	a->out = out;
}

void setSamplerate_nob (NOB a, int rate)
{
	a->samplerate = rate;
	init_nob (a);
}

void setSize_nob (NOB a, int size)
{
	a->buffsize = size;
	flush_nob (a);
}

/********************************************************************************************************
*																										*
*										POINTER-BASED PROPERTIES										*
*																										*
********************************************************************************************************/

PORT
void pSetRCVRNOBRun (NOB a, int run)
{
	EnterCriticalSection (&a->cs_update);
	a->run = run;
	LeaveCriticalSection (&a->cs_update);
}

PORT
void pSetRCVRNOBMode (NOB a, int mode)
{
	EnterCriticalSection (&a->cs_update);
	a->mode = mode;
	LeaveCriticalSection (&a->cs_update);
}

PORT
void pSetRCVRNOBBuffsize (NOB a, int size)
{
	EnterCriticalSection (&a->cs_update);
	a->buffsize = size;
	LeaveCriticalSection (&a->cs_update);
}

PORT
void pSetRCVRNOBSamplerate (NOB a, int rate)
{
	EnterCriticalSection (&a->cs_update);
	a->samplerate = (double) rate;
	init_nob (a);
	LeaveCriticalSection (&a->cs_update);
}

PORT
void pSetRCVRNOBTau (NOB a, double tau)
{
	EnterCriticalSection (&a->cs_update);
	a->advslewtime = tau;
	a->hangslewtime = tau;
	init_nob (a);
	LeaveCriticalSection (&a->cs_update);
}

PORT
void pSetRCVRNOBHangtime (NOB a, double time)
{
	EnterCriticalSection (&a->cs_update);
	a->hangtime = time;
	init_nob (a);
	LeaveCriticalSection (&a->cs_update);
}

PORT
void pSetRCVRNOBAdvtime (NOB a, double time)
{
	EnterCriticalSection (&a->cs_update);
	a->advtime = time;
	init_nob (a);
	LeaveCriticalSection (&a->cs_update);
}

PORT
void pSetRCVRNOBBacktau (NOB a, double tau)
{
	EnterCriticalSection (&a->cs_update);
	a->backtau = tau;
	init_nob (a);
	LeaveCriticalSection (&a->cs_update);
}

PORT
void pSetRCVRNOBThreshold (NOB a, double thresh)
{
	EnterCriticalSection (&a->cs_update);
	a->threshold = thresh;
	LeaveCriticalSection (&a->cs_update);
}

/********************************************************************************************************
*																										*
*										CALLS FOR EXTERNAL USE											*
*																										*
********************************************************************************************************/

#define MAX_EXT_NOBS	(32)						// maximum number of NOBs called from outside wdsp
__declspec (align (16)) NOB pnob[MAX_EXT_NOBS];		// array of pointers for NOBs used EXTERNAL to wdsp

PORT
void create_nobEXT	(
	int id,
	int run,
	int mode,
	int buffsize,
	double samplerate,
	double slewtime,
	double hangtime,
	double advtime,
	double backtau,
	double threshold
					)
{
	double advslewtime = slewtime;
	double hangslewtime = slewtime;
	double max_imp_seq_time = 0.025;
	pnob[id] = create_nob (run, buffsize, 0, 0, samplerate, mode, advslewtime, advtime, hangslewtime, hangtime, max_imp_seq_time, backtau, threshold);
}

PORT
void destroy_nobEXT (int id)
{
	destroy_nob (pnob[id]);
}

PORT
void flush_nobEXT (int id)
{
	flush_nob (pnob[id]);
}

PORT
void xnobEXT (int id, double* in, double* out)
{
	NOB a = pnob[id];
	a->in = in;
	a->out = out;
	xnob (a);
}

PORT
void SetEXTNOBRun (int id, int run)
{
	NOB a = pnob[id];
	EnterCriticalSection (&a->cs_update);
	a->run = run;
	LeaveCriticalSection (&a->cs_update);
}

PORT
void SetEXTNOBMode (int id, int mode)
{
	NOB a = pnob[id];
	EnterCriticalSection (&a->cs_update);
	a->mode = mode;
	LeaveCriticalSection (&a->cs_update);
}

PORT
void SetEXTNOBBuffsize (int id, int size)
{
	NOB a = pnob[id];
	EnterCriticalSection (&a->cs_update);
	a->buffsize = size;
	LeaveCriticalSection (&a->cs_update);
}

PORT
void SetEXTNOBSamplerate (int id, int rate)
{
	NOB a = pnob[id];
	EnterCriticalSection (&a->cs_update);
	a->samplerate = (double) rate;
	init_nob (a);
	LeaveCriticalSection (&a->cs_update);
}

PORT
void SetEXTNOBTau (int id, double tau)
{
	NOB a = pnob[id];
	EnterCriticalSection (&a->cs_update);
	a->advslewtime = tau;
	a->hangslewtime = tau;
	init_nob (a);
	LeaveCriticalSection (&a->cs_update);
}

PORT
void SetEXTNOBHangtime (int id, double time)
{
	NOB a = pnob[id];
	EnterCriticalSection (&a->cs_update);
	a->hangtime = time;
	init_nob (a);
	LeaveCriticalSection (&a->cs_update);
}

PORT
void SetEXTNOBAdvtime (int id, double time)
{
	NOB a = pnob[id];
	EnterCriticalSection (&a->cs_update);
	a->advtime = time;
	init_nob (a);
	LeaveCriticalSection (&a->cs_update);
}

PORT
void SetEXTNOBBacktau (int id, double tau)
{
	NOB a = pnob[id];
	EnterCriticalSection (&a->cs_update);
	a->backtau = tau;
	init_nob (a);
	LeaveCriticalSection (&a->cs_update);
}

PORT
void SetEXTNOBThreshold (int id, double thresh)
{
	NOB a = pnob[id];
	EnterCriticalSection (&a->cs_update);
	a->threshold = thresh;
	LeaveCriticalSection (&a->cs_update);
}

/********************************************************************************************************
*																										*
*											LEGACY INTERFACE											*
*																										*
********************************************************************************************************/

PORT
void xnobEXTF (int id, float *I, float *Q)
{
	int i;
	NOB a = pnob[id];
	a->in = a->legacy;
	a->out = a->legacy;
	for (i = 0; i < a->buffsize; i++)
	{
		a->legacy[2 * i + 0] = (double)I[i];
		a->legacy[2 * i + 1] = (double)Q[i];
	}
	xnob (a);
	for (i = 0; i < a->buffsize; i++)
	{
		I[i] = (float)a->legacy[2 * i + 0];
		Q[i] = (float)a->legacy[2 * i + 1];
	}
}
