/* PSK31  -- receiver classs
 */

#ifndef PSK31_RECEIVER_H_INCLUDED
#define PSK31_RECEIVER_H_INCLUDED

#define FIR1TAPS 64
#define FIR2TAPS 64

#include "psk31-coder.h"
#include "psk31-fft.h"

/* receiver channel interface class */
class psk31_receiver {
private:
	int qpsk;        /* QPSK mode on */
	int lsb;         /* inverted mode */
	float _rxfreq;
	int rxfreq;
	int rxphase;
	int strength;    /* logarithmic RX signal strength; 0..40 */
	int dcd;         /* dcd flag */
	int dcdlevel;    /* -1=ignore dcd, 0=plain pre/postamble dcd,
			    otherwise: level 1..100 for dcd sensitivity */
	int afc;         /* AFC flag */
	int noiselevel;  /* test only: simulated addition noise */
	int dofft;       /* freq scan via fft activation */
	int lastdelta;
	psk31_coder coder;

	/* for DCD calculation... */
	unsigned long dcdshfreg;
	float is,qs;              // signal quality estimator

	/* fft stuff */
	float fft_result;
	float fftbufI[1024], fftbufQ[1024];
	int fftind;

	/* receive filters */
	float ibuf1_I[FIR1TAPS];
	float ibuf1_Q[FIR1TAPS];
	float ibuf2_I[FIR2TAPS];
	float ibuf2_Q[FIR2TAPS];
	int amp_buf[16];
	float amp_buf_new[16];
	int ibuf1_cur, ibuf2_cur; /*index of oldest sample/place for new one */
	int lastphase; /* phase of last rx symbol... */
	int bitclk;    /* phase synchronisation */

	int stat;        /* cyclic state counter for receiver */
	char *decode_buffer;

	float do_fir(float *base, int cur, float *coeff, int len);

	psk31_fft *pskfft;

	int process_500();
	int process_rx_symbol(cmplx rxsymb);
	void dodcd(int diffphase);
	void doafc(int symb);
	void pdistr(float *I, float *Q);
	void perform_fft(float I, float Q);
	int diffphase2symbol(int diffphase);
	FILE *writefile;
public:
	psk31_receiver(psk31_fft *fft) { 
		pskfft = fft;
		stat=0; ibuf1_cur=ibuf2_cur=0; rxphase=0;
		for(int i=0; i<16; i++) amp_buf[i]=0;
		set_freq(1250); dofft=0; lastdelta=0;
		for(int i=0; i<FIR1TAPS; i++) ibuf1_I[i]=ibuf1_Q[i]=0;
		for(int i=0; i<FIR2TAPS; i++) ibuf2_I[i]=ibuf2_Q[i]=0;
		coder.prime_decoder();
		dcd = qpsk = lsb = dcdlevel = afc = lastdelta = strength = 0;
		rxfreq = 1000;
		_rxfreq = 1000.0; // just to NOT have unitialized values!
#if 0
		char filename[128];
		sprintf(filename,"dcdlog%p",this);
		writefile=fopen(filename,"w");
		if(writefile==NULL) {
			perror(filename);
		} else fprintf(stderr,"Ok!\n");
#endif
		is=qs=0;
	}
	psk31_fft *get_fft() { return pskfft; }
	void set_fft(psk31_fft *fft) { pskfft = fft; }
	int set_mode(int qpsk_flag, int lsb_flag=0) { 
		qpsk=qpsk_flag; lsb=lsb_flag;
		coder.setmode(qpsk, lsb);
		return 0;
	}
	void set_afc(int afc_flag) { afc=afc_flag; }
	void set_dcdlevel(int dcd_flag) { dcdlevel=dcd_flag; }
	void set_dcd(int dcd_flag) { dcd=dcd_flag; }
	void set_freq(float f) { _rxfreq=f; rxfreq=(int)(65536.0/8000*f); }
	void get_info(int *q, int *l, float *f, int *dlevel, int *a, int *d,
		      int *stat, int *streng) {
		if(q) *q=qpsk; if(l) *l=lsb; if(f) *f=_rxfreq;
		if(dlevel) *dlevel=dcdlevel; if(a) *a=afc; if(d) *d=dcd;
		if(stat) *stat=lastdelta;
		if(streng) *streng=strength;
	}
	float get_freq() { return _rxfreq; }
	void enable_fft(int f) { dofft=f; }
	float get_fft_result() { return fft_result; }
	int process_rx_sample(short sample); /* return: 0=no new char;
                                                1=new char -1=buffer full */
};


#endif