/*
 * IGC parser
 * @brief parse IGC file, get all data points, compute average horizontal/vertical speed, print to STDOUT
 *
 * As per standard: https://xp-soaring.github.io/igc_file_format/igc_format_2008.html
 *                  https://xp-soaring.github.io/igc_file_format/igc_fr_specification_with_al8_2023-2-1_0.pdf
 *
 * @author xamidev <xamidev@riseup.net>
 * @license GNU GPL v3
 */

#include <stdio.h>
#include <stdlib.h>
#include <errno.h>
#include <string.h>
#include "igc.h"

void parse_igc_file(FILE* fp)
{
	size_t len = 0;
	char* line = NULL;

	while (getline(&line, &len, fp)	!= -1)
	{
		switch(line[0])
		{
			case DATAPOINT:
				struct IGC_DataPoint* dp = (struct IGC_DataPoint*)malloc(sizeof(struct IGC_DataPoint));	
				char hour[3], min[3], sec[3] = {0};
				char lat_d[3], lat_m[3], lat_s[4] = {0};
				char lon_d[4], lon_m[3], lon_s[4] = {0};

				memcpy(hour, line+1, 2);
				memcpy(min, line+3, 2);
				memcpy(sec, line+5, 2);
				memcpy(lat_d, line+7, 2);
				memcpy(lat_m, line+9, 2);
				memcpy(lat_s, line+11, 3);
				memcpy(lon_d, line+15, 3);
				memcpy(lon_m, line+18, 2);	
				memcpy(lon_s, line+20, 3);

				dp->hour = atoi(hour);
				dp->minute = atoi(min);
				dp->second = atoi(sec);
				dp->lat.deg = atoi(lat_d);
				dp->lat.min = atoi(lat_m);
				dp->lat.sec = atoi(lat_s);
				dp->lat.cardinal = line[14] == NORTH ? NORTH : SOUTH;
				dp->lon.deg = atoi(lon_d);
				dp->lon.min = atoi(lon_m);
				dp->lon.sec = atoi(lon_s);
				dp->lon.cardinal = line[23] == EAST ? EAST : WEST;
				
				printf("%s", line);
				printf("Data point: %d:%d:%d | %d°%d'%d\"%c %d°%d'%d\"%c\n", dp->hour, dp->minute, dp->second, dp->lat.deg, dp->lat.min, dp->lat.sec, dp->lat.cardinal, dp->lon.deg, dp->lon.min, dp->lon.sec, dp->lon.cardinal);

				// Debug
				exit(0);
				break;
			default:
				break;
		}
	}
}

int main(int argc, char* argv[])
{
	if (argc < 2)
	{
		printf("Usage: %s <file>\n", argv[0]);
		return -EINVAL;
	}

	char filename[NAME_MAX] = {0};
	strncpy(filename, argv[1], NAME_MAX-1);

	FILE* fp = fopen(filename, "r");

	if (!fp)
	{
		printf("Couldn't open file %s\n", filename);
		return -EINVAL;
	}

	parse_igc_file(fp);

	return EXIT_SUCCESS;
}