/**
 *
 * \section COPYRIGHT
 *
 * Copyright 2013-2014 The libLTE Developers. See the
 * COPYRIGHT file at the top-level directory of this distribution.
 *
 * \section LICENSE
 *
 * This file is part of the libLTE library.
 *
 * libLTE is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Lesser General Public License as
 * published by the Free Software Foundation, either version 3 of
 * the License, or (at your option) any later version.
 *
 * libLTE 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 Lesser General Public License for more details.
 *
 * A copy of the GNU Lesser General Public License can be found in
 * the LICENSE file in the top-level directory of this distribution
 * and at http://www.gnu.org/licenses/.
 *
 */

#include <stdio.h>
#include <stdlib.h>
#include <strings.h>
#include <unistd.h>
#include <sys/time.h>

#include "lte.h"

char *input_file_name;
char *output_file_name="abs_corr.txt";
int nof_frames=100, frame_length=9600, symbol_sz=128;
float corr_peak_threshold=25.0;
int file_binary = 0;
int out_N_id_2 = 0, force_N_id_2=-1;

#define CFO_AUTO	-9999.0
float force_cfo = CFO_AUTO;

void usage(char *prog) {
	printf("Usage: %s [onlt] -i input_file\n", prog);
	printf("\t-o output_file [Default %s]\n", output_file_name);
	printf("\t-l frame_length [Default %d]\n", frame_length);
	printf("\t-n number of frames [Default %d]\n", nof_frames);
	printf("\t-t correlation threshold [Default %g]\n", corr_peak_threshold);
	printf("\t-s symbol_sz [Default %d]\n", symbol_sz);
	printf("\t-b Input files is binary [Default %s]\n", file_binary?"yes":"no");
	printf("\t-N out_N_id_2 [Default %d]\n", out_N_id_2);
	printf("\t-f force_N_id_2 [Default %d]\n", force_N_id_2);
	printf("\t-c force_cfo [Default disabled]\n");
}

void parse_args(int argc, char **argv) {
	int opt;
	while ((opt = getopt(argc, argv, "ionltsbNfc")) != -1) {
		switch(opt) {
		case 'i':
			input_file_name = argv[optind];
			break;
		case 'o':
			output_file_name = argv[optind];
			break;
		case 'n':
			nof_frames = atoi(argv[optind]);
			break;
		case 'l':
			frame_length = atoi(argv[optind]);
			break;
		case 't':
			corr_peak_threshold = atof(argv[optind]);
			break;
		case 's':
			symbol_sz = atof(argv[optind]);
			break;
		case 'b':
			file_binary = 1;
			break;
		case 'N':
			out_N_id_2 = atoi(argv[optind]);
			break;
		case 'f':
			force_N_id_2 = atoi(argv[optind]);
			break;
		case 'c':
			force_cfo = atof(argv[optind]);
			break;
		default:
			usage(argv[0]);
			exit(-1);
		}
	}
	if (!input_file_name) {
		usage(argv[0]);
		exit(-1);
	}
}

int main(int argc, char **argv) {
	filesource_t fsrc;
	filesink_t fsink;
	pss_synch_t pss[3]; // One for each N_id_2
	sss_synch_t sss[3]; // One for each N_id_2
	cfo_t cfocorr;
	int peak_pos[3];
	float *cfo;
	float peak_value[3];
	float mean_value[3];
	int frame_cnt;
	cf_t *input;
	int m0, m1;
	float m0_value, m1_value;
	int N_id_2;
	int sss_idx;
	struct timeval tdata[3];
	int *exec_time;

	if (argc < 3) {
		usage(argv[0]);
		exit(-1);
	}

	parse_args(argc,argv);

	gettimeofday(&tdata[1], NULL);
	printf("Initializing...");fflush(stdout);

	data_type_t type = file_binary?COMPLEX_FLOAT_BIN:COMPLEX_FLOAT;
	if (filesource_init(&fsrc, input_file_name, type)) {
		fprintf(stderr, "Error opening file %s\n", input_file_name);
		exit(-1);
	}
	if (filesink_init(&fsink, output_file_name, type)) {
		fprintf(stderr, "Error opening file %s\n", output_file_name);
		exit(-1);
	}

	input = malloc(frame_length*sizeof(cf_t));
	if (!input) {
		perror("malloc");
		exit(-1);
	}
	cfo = malloc(nof_frames*sizeof(float));
	if (!cfo) {
		perror("malloc");
		exit(-1);
	}
	exec_time = malloc(nof_frames*sizeof(int));
	if (!exec_time) {
		perror("malloc");
		exit(-1);
	}

	if (cfo_init(&cfocorr, frame_length)) {
		fprintf(stderr, "Error initiating CFO\n");
		return -1;
	}

	/* We have 2 options here:
	 * a) We create 3 pss objects, each initialized with a different N_id_2
	 * b) We create 1 pss object which scans for each N_id_2 one after another.
	 * a) requries more memory but has less latency and is paralellizable.
	 */
	for (N_id_2=0;N_id_2<3;N_id_2++) {
		if (pss_synch_init(&pss[N_id_2], frame_length)) {
			fprintf(stderr, "Error initializing PSS object\n");
			exit(-1);
		}
		if (pss_synch_set_N_id_2(&pss[N_id_2], N_id_2)) {
			fprintf(stderr, "Error initializing N_id_2\n");
			exit(-1);
		}
		if (sss_synch_init(&sss[N_id_2])) {
			fprintf(stderr, "Error initializing SSS object\n");
			exit(-1);
		}
		if (sss_synch_set_N_id_2(&sss[N_id_2], N_id_2)) {
			fprintf(stderr, "Error initializing N_id_2\n");
			exit(-1);
		}
	}
	gettimeofday(&tdata[2], NULL);
	get_time_interval(tdata);
	printf("done in %d s %d ms\n", (int) tdata[0].tv_sec, (int) tdata[0].tv_usec/1000);

	printf("\n\tFr.Cnt\tN_id_2\tN_id_1\tSubf\tPSS Peak/Avg\tIdx\tm0\tm1\tCFO\n");
	printf("\t===============================================================================\n");

	/* read all file or nof_frames */
	frame_cnt = 0;
	while (frame_length == filesource_read(&fsrc, input, frame_length)
			&& frame_cnt < nof_frames) {

		gettimeofday(&tdata[1], NULL);
		if (force_cfo != CFO_AUTO) {
			cfo_correct(&cfocorr, input, -force_cfo/128);
		}

		if (force_N_id_2 != -1) {
			N_id_2 = force_N_id_2;
			peak_pos[N_id_2] = pss_synch_find_pss(&pss[N_id_2], input, &peak_value[N_id_2], &mean_value[N_id_2]);
		} else {
			for (N_id_2=0;N_id_2<3;N_id_2++) {
				peak_pos[N_id_2] = pss_synch_find_pss(&pss[N_id_2], input, &peak_value[N_id_2], &mean_value[N_id_2]);
			}
			float max_value=-99999;
			N_id_2=-1;
			int i;
			for (i=0;i<3;i++) {
				if (peak_value[i] > max_value) {
					max_value = peak_value[i];
					N_id_2 = i;
				}
			}
		}

		/* If peak detected */
		if (peak_value[N_id_2]/mean_value[N_id_2] > corr_peak_threshold) {

			sss_idx = peak_pos[N_id_2]-2*(symbol_sz+CP(symbol_sz,CPNORM_LEN));
			if (sss_idx >= 0) {
				sss_synch_m0m1(&sss[N_id_2], &input[sss_idx],
						&m0, &m0_value, &m1, &m1_value);

				cfo[frame_cnt] = pss_synch_cfo_compute(&pss[N_id_2], &input[peak_pos[N_id_2]-128]);
				printf("\t%d\t%d\t%d\t%d\t%.3f\t\t%3d\t%d\t%d\t%.3f\n",
						frame_cnt,N_id_2, sss_synch_N_id_1(&sss[N_id_2], m0, m1),
						sss_synch_subframe(m0, m1), peak_value[N_id_2]/mean_value[N_id_2],
						peak_pos[N_id_2], m0, m1,
						cfo[frame_cnt]);
			}
		}
		gettimeofday(&tdata[2], NULL);
		get_time_interval(tdata);
		exec_time[frame_cnt] = tdata[0].tv_usec;
		frame_cnt++;
	}

	int i;
	float avg_time=0;
	for (i=0;i<frame_cnt;i++) {
		avg_time += (float) exec_time[i];
	}
	avg_time /= frame_cnt;
	printf("\n");
	printf("Average exec time: %.3f ms / frame. %.3f Msamp/s (%.3f\%% CPU)\n",
			avg_time / 1000, frame_length / avg_time, 100 * avg_time / 5000 * (9600 / (float) frame_length ));

	float cfo_mean=0;
	for (i=0;i<frame_cnt;i++) {
		cfo_mean += cfo[i] / frame_cnt * (9600 / frame_length);
	}
	printf("Average CFO: %.3f\n", cfo_mean);

	for (N_id_2=0;N_id_2<3;N_id_2++) {
		pss_synch_free(&pss[N_id_2]);
		sss_synch_free(&sss[N_id_2]);
	}

	filesource_free(&fsrc);
	filesink_free(&fsink);

	free(input);
	free(cfo);

	printf("Done\n");
	exit(0);
}