/*
 * (C) Copyright 2014 Leo C. <erbl259-lmu@yahoo.de>
 *
 * (C) Copyright 2001
 * Wolfgang Denk, DENX Software Engineering, wd@denx.de.
 *
 * SPDX-License-Identifier:	GPL-2.0+
 */

/*
 * RTC, Date & Time support: get and set date & time
 */
#include "common.h"
#include <string.h>
#include "time.h"
#include "rtc.h"
#include "command.h"


/*
 * simple conversion of two-digit string with error checking
 */
static int cnvrt2 (const char *str, int *valp)
{
	int val;

	if ((*str < '0') || (*str > '9'))
		return (-1);

	val = *str - '0';

	++str;

	if ((*str < '0') || (*str > '9'))
		return (-1);

	*valp = 10 * val + (*str - '0');

	return (0);
}

/*
 * Convert date string: MMDDhhmm[[CC]YY][.ss]
 *
 * Some basic checking for valid values is done, but this will not catch
 * all possible error conditions.
 */
int mk_date (const char *datestr, struct tm *tmp)
{
	int len, val;
	char *ptr;

	ptr = strchr (datestr,'.');
	len = strlen (datestr);

	/* Set seconds */
	if (ptr) {
		int sec;

		*ptr++ = '\0';
		if ((len - (ptr - datestr)) != 2)
			return (-1);

		len = strlen (datestr);

		if (cnvrt2 (ptr, &sec))
			return (-1);

		tmp->tm_sec = sec;
	} else {
		tmp->tm_sec = 0;
	}

	if (len == 12) {			/* MMDDhhmmCCYY	*/
		int year, century;

		if (cnvrt2 (datestr+ 8, &century) ||
		    cnvrt2 (datestr+10, &year) ) {
			return (-1);
		}
		tmp->tm_year = 100 * century + year - 1900;
	} else if (len == 10) {		/* MMDDhhmmYY	*/
		int year, century;

		century = (tmp->tm_year + 1900) / 100;
		if (cnvrt2 (datestr+ 8, &year))
			return (-1);
		tmp->tm_year = 100 * century + year -1900;
	}

	switch (len) {
	case 8:					/* MMDDhhmm	*/
		/* fall thru */
	case 10:				/* MMDDhhmmYY	*/
		/* fall thru */
	case 12:				/* MMDDhhmmCCYY	*/
		if (cnvrt2 (datestr+0, &val) ||
		    val > 12) {
			break;
		}
		tmp->tm_mon  = val - 1;
		if (cnvrt2 (datestr+2, &val) ||
		    val > ((tmp->tm_mon==2-1) ? 29 : 31)) {
			break;
		}
		tmp->tm_mday = val;

		if (cnvrt2 (datestr+4, &val) ||
		    val > 23) {
			break;
		}
		tmp->tm_hour = val;

		if (cnvrt2 (datestr+6, &val) ||
		    val > 59) {
			break;
		}
		tmp->tm_min  = val;

		return (0);
	default:
		break;
	}

	return (-1);
}

command_ret_t do_date(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
{
	struct tm t;
	char buf[30];
	int rc;
	command_ret_t rcode = CMD_RET_FAILURE;

	(void) cmdtp; (void) flag;

	switch (argc) {
	case 2:			/* set date & time */
		/* initialize t with current time */
		if(rtc_get(&t) < 0) {
			my_puts_P(PSTR("## Get date failed\n"));
			break;
		} else {
			/* insert new date & time */
			if (mk_date (argv[1], &t) != 0) {
				my_puts_P(PSTR("## Bad date format\n"));
				break;
			}

			time_t time;
			time = mk_gmtime(&t);
			gmtime_r(&time, &t);

			/* and write to RTC */
			if(rtc_set(&t) < 0) {
				my_puts_P(PSTR("## Set date failed\n"));
				break;
			}
		}
		/* FALL TROUGH */
	case 1:			/* get date & time */
		rc = rtc_get(&t);
		if (rc >= 0) {
			asctime_r(&t, buf);
			printf_P(PSTR("%s"), buf);
			if (rc == 1)
				printf_P(PSTR("  (Invalid)"));
			putchar('\n');
			rcode = CMD_RET_SUCCESS;
		} else {
			my_puts_P(PSTR("## Get date failed\n"));
		}
		break;

	default:
		rcode = CMD_RET_USAGE;
	}

	return rcode;
}