/*
 * gsmefr-etsi-enc is a test program for our EFR encoder: it reads raw
 * 16-bit PCM (matching ETSI's *.inp) as input and writes ETSI's *.cod
 * format as output, allowing our decoder to be tested with ETSI's
 * official test sequences.
 *
 * ETSI input and output files are read and written in LE byte order,
 * matching the official test sequences in ts_100725v050200p0.zip.
 */

#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
#include <strings.h>
#include "../libgsmefr/gsm_efr.h"

static int
read_input(inf, pcm, filename_for_errs)
	FILE *inf;
	int16_t *pcm;
	char *filename_for_errs;
{
	uint8_t file_bytes[320], *sp;
	int cc;
	unsigned n;

	cc = fread(file_bytes, 2, 160, inf);
	if (cc == 0)
		return 0;
	if (cc != 160) {
		fprintf(stderr, "error: short read from %s\n",
			filename_for_errs);
		exit(1);
	}
	sp = file_bytes;
	for (n = 0; n < 160; n++) {
		pcm[n] = sp[0] | (sp[1] << 8);
		sp += 2;
	}
	return 1;
}

static void
frame2bits(frame, bits)
	uint8_t *frame, *bits;
{
	unsigned nb, byte, mask, bit;

	for (nb = 0; nb < EFR_RTP_FRAME_LEN; nb++) {
		byte = *frame++;
		for (mask = 0x80; mask; mask >>= 1) {
			if (byte & mask)
				bit = 1;
			else
				bit = 0;
			*bits++ = bit;
		}
	}
}

static void
emit_output(outf, bits, nbits)
	FILE *outf;
	uint8_t *bits;
	unsigned nbits;
{
	unsigned n;

	for (n = 0; n < nbits; n++) {
		putc(bits[n], outf);
		putc(0, outf);
	}
}

main(argc, argv)
	char **argv;
{
	char *infname, *outfname;
	FILE *inf, *outf;
	struct EFR_encoder_state *state;
	int16_t pcm[160];
	uint8_t frame[EFR_RTP_FRAME_LEN], bits[250];
	int dtx, rc, sp, vad;

	if (argc == 3 && argv[1][0] != '-') {
		dtx = 0;
		infname = argv[1];
		outfname = argv[2];
	} else if (argc == 4 && !strcmp(argv[1], "-d")) {
		dtx = 1;
		infname = argv[2];
		outfname = argv[3];
	} else {
		fprintf(stderr, "usage: %s [-d] input.inp output.cod\n",
			argv[0]);
		exit(1);
	}
	inf = fopen(infname, "r");
	if (!inf) {
		perror(infname);
		exit(1);
	}
	outf = fopen(outfname, "w");
	if (!outf) {
		perror(outfname);
		exit(1);
	}
	state = EFR_encoder_create(dtx);
	if (!state) {
		perror("EFR_encoder_create()");
		exit(1);
	}
	for (;;) {
		rc = read_input(inf, pcm, argv[1]);
		if (!rc)
			break;
		EFR_encode_frame(state, pcm, frame, &sp, &vad);
		frame2bits(frame, bits);
		bits[248] = vad;
		bits[249] = sp;
		emit_output(outf, bits + 4, 246);
	}
	fclose(outf);
	exit(0);
}