/*
 * The MIT License (MIT)
 *
 * Copyright (c) 2015-2019 Derick Rethans
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 *
 * Portions copyright (c) 1998-2017 Zend Technologies Ltd.
 *
 * The timelib_strcasecmp and timelib_strncasecmp are taken from PHP's
 * Zend/zend_operators.[hc] source files.
 *
 */

#include "timelib.h"
#include "timelib_private.h"
#include <ctype.h>
#include <math.h>

#define TIMELIB_LLABS(y) (y < 0 ? (y * -1) : y)

const char *timelib_error_messages[10] = {
	"No error",
	"Cannot allocate buffer for parsing",
	"Corrupt tzfile: The transitions in the file don't always increase",
	"Corrupt tzfile: The expected 64-bit preamble is missing",
	"Corrupt tzfile: No abbreviation could be found for a transition",
	"The version used in this timezone identifier is unsupported",
	"No timezone with this name could be found",
	"A 'slim' timezone file has been detected",
	"The embedded POSIX string is not valid",
	"The embedded POSIX string is empty"
};

const char *timelib_get_error_message(int error_code)
{
	int entries = sizeof(timelib_error_messages) / sizeof(char*);

	if (error_code >= 0 && error_code < entries) {
		return timelib_error_messages[error_code];
	}
	return "Unknown error code";
}

timelib_time* timelib_time_ctor(void)
{
	timelib_time *t;
	t = timelib_calloc(1, sizeof(timelib_time));

	return t;
}

void timelib_time_dtor(timelib_time* t)
{
	TIMELIB_TIME_FREE(t->tz_abbr);
	TIMELIB_TIME_FREE(t);
}

int timelib_time_compare(timelib_time *t1, timelib_time *t2)
{
	if (t1->sse == t2->sse) {
		if (t1->us == t2->us) {
			return 0;
		}

		return (t1->us < t2->us) ? -1 : 1;
	}

	return (t1->sse < t2->sse) ? -1 : 1;
}

timelib_time* timelib_time_clone(timelib_time *orig)
{
	timelib_time *tmp = timelib_time_ctor();
	memcpy(tmp, orig, sizeof(timelib_time));
	if (orig->tz_abbr) {
		tmp->tz_abbr = timelib_strdup(orig->tz_abbr);
	}
	if (orig->tz_info) {
		tmp->tz_info = orig->tz_info;
	}
	return tmp;
}

timelib_rel_time* timelib_rel_time_ctor(void)
{
	timelib_rel_time *t;
	t = timelib_calloc(1, sizeof(timelib_rel_time));

	return t;
}

void timelib_rel_time_dtor(timelib_rel_time* t)
{
	TIMELIB_TIME_FREE(t);
}

timelib_rel_time* timelib_rel_time_clone(timelib_rel_time *rel)
{
	timelib_rel_time *tmp = timelib_rel_time_ctor();
	memcpy(tmp, rel, sizeof(timelib_rel_time));
	return tmp;
}

void timelib_time_tz_abbr_update(timelib_time* tm, const char* tz_abbr)
{
	unsigned int i;
	size_t tz_abbr_len = strlen(tz_abbr);

	TIMELIB_TIME_FREE(tm->tz_abbr);
	tm->tz_abbr = timelib_strdup(tz_abbr);
	for (i = 0; i < tz_abbr_len; i++) {
		tm->tz_abbr[i] = toupper(tz_abbr[i]);
	}
}

timelib_time_offset* timelib_time_offset_ctor(void)
{
	timelib_time_offset *t;
	t = timelib_calloc(1, sizeof(timelib_time_offset));

	return t;
}

void timelib_time_offset_dtor(timelib_time_offset* t)
{
	TIMELIB_TIME_FREE(t->abbr);
	TIMELIB_TIME_FREE(t);
}

char *timelib_get_tz_abbr_ptr(timelib_time *t)
{
	if (!t->sse_uptodate) {
		timelib_update_ts(t, NULL);
	};
	return t->tz_abbr;
}

void timelib_error_container_dtor(timelib_error_container *errors)
{
	int i;

	for (i = 0; i < errors->warning_count; i++) {
		timelib_free(errors->warning_messages[i].message);
	}
	timelib_free(errors->warning_messages);
	for (i = 0; i < errors->error_count; i++) {
		timelib_free(errors->error_messages[i].message);
	}
	timelib_free(errors->error_messages);
	timelib_free(errors);
}

timelib_long timelib_date_to_int(timelib_time *d, int *error)
{
	timelib_sll ts;

	ts = d->sse;

	if (ts < TIMELIB_LONG_MIN || ts > TIMELIB_LONG_MAX) {
		if (error) {
			*error = 1;
		}
		return 0;
	}
	if (error) {
		*error = 0;
	}
	return (timelib_long) d->sse;
}

void timelib_decimal_hour_to_hms(double h, int *hour, int *min, int *sec)
{
	bool swap = false;
	int seconds;

	if (h < 0) {
		swap = true;
		h = fabs(h);
	}

	*hour = floor(h);
	seconds = floor((h - *hour) * 3600);

	*min = seconds / 60;
	*sec = seconds % 60;

	if (swap) {
		*hour = 0 - *hour;
	}
}

void timelib_hms_to_decimal_hour(int hour, int min, int sec, double *h)
{
	if (hour >= 0) {
		*h = ((double)hour + (double)min / 60 + (double)sec / 3600);
	} else {
		*h = ((double)hour - (double)min / 60 - (double)sec / 3600);
	}
}

void timelib_hmsf_to_decimal_hour(int hour, int min, int sec, int us, double *h)
{
	if (hour >= 0) {
		*h = ((double)hour + (double)min / MINS_PER_HOUR + (double)sec / SECS_PER_HOUR) + (double)us / USECS_PER_HOUR;
	} else {
		*h = ((double)hour - (double)min / MINS_PER_HOUR - (double)sec / SECS_PER_HOUR) - (double)us / USECS_PER_HOUR;
	}
}

timelib_sll timelib_hms_to_seconds(timelib_sll h, timelib_sll m, timelib_sll s)
{
	return (h * SECS_PER_HOUR) + (m * 60) + s;
}

static const unsigned char timelib_tolower_map[256] = {
	0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07, 0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
	0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17, 0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
	0x20, 0x21, 0x22, 0x23, 0x24, 0x25, 0x26, 0x27, 0x28, 0x29, 0x2a, 0x2b, 0x2c, 0x2d, 0x2e, 0x2f,
	0x30, 0x31, 0x32, 0x33, 0x34, 0x35, 0x36, 0x37, 0x38, 0x39, 0x3a, 0x3b, 0x3c, 0x3d, 0x3e, 0x3f,
	0x40, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
	0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x5b, 0x5c, 0x5d, 0x5e, 0x5f,
	0x60, 0x61, 0x62, 0x63, 0x64, 0x65, 0x66, 0x67, 0x68, 0x69, 0x6a, 0x6b, 0x6c, 0x6d, 0x6e, 0x6f,
	0x70, 0x71, 0x72, 0x73, 0x74, 0x75, 0x76, 0x77, 0x78, 0x79, 0x7a, 0x7b, 0x7c, 0x7d, 0x7e, 0x7f,
	0x80, 0x81, 0x82, 0x83, 0x84, 0x85, 0x86, 0x87, 0x88, 0x89, 0x8a, 0x8b, 0x8c, 0x8d, 0x8e, 0x8f,
	0x90, 0x91, 0x92, 0x93, 0x94, 0x95, 0x96, 0x97, 0x98, 0x99, 0x9a, 0x9b, 0x9c, 0x9d, 0x9e, 0x9f,
	0xa0, 0xa1, 0xa2, 0xa3, 0xa4, 0xa5, 0xa6, 0xa7, 0xa8, 0xa9, 0xaa, 0xab, 0xac, 0xad, 0xae, 0xaf,
	0xb0, 0xb1, 0xb2, 0xb3, 0xb4, 0xb5, 0xb6, 0xb7, 0xb8, 0xb9, 0xba, 0xbb, 0xbc, 0xbd, 0xbe, 0xbf,
	0xc0, 0xc1, 0xc2, 0xc3, 0xc4, 0xc5, 0xc6, 0xc7, 0xc8, 0xc9, 0xca, 0xcb, 0xcc, 0xcd, 0xce, 0xcf,
	0xd0, 0xd1, 0xd2, 0xd3, 0xd4, 0xd5, 0xd6, 0xd7, 0xd8, 0xd9, 0xda, 0xdb, 0xdc, 0xdd, 0xde, 0xdf,
	0xe0, 0xe1, 0xe2, 0xe3, 0xe4, 0xe5, 0xe6, 0xe7, 0xe8, 0xe9, 0xea, 0xeb, 0xec, 0xed, 0xee, 0xef,
	0xf0, 0xf1, 0xf2, 0xf3, 0xf4, 0xf5, 0xf6, 0xf7, 0xf8, 0xf9, 0xfa, 0xfb, 0xfc, 0xfd, 0xfe, 0xff
};

#define timelib_tolower(c) (timelib_tolower_map[(unsigned char)(c)])
#undef MIN
#undef MAX
#define MAX(a, b)  (((a)>(b))?(a):(b))
#define MIN(a, b)  (((a)<(b))?(a):(b))

int timelib_strcasecmp(const char *s1, const char *s2)
{
	size_t len;
	size_t len1 = strlen(s1);
	size_t len2 = strlen(s2);
	int c1, c2;

	if (s1 == s2) {
		return 0;
	}

	len = MIN(len1, len2);
	while (len--) {
		c1 = timelib_tolower(*(unsigned char *)s1++);
		c2 = timelib_tolower(*(unsigned char *)s2++);
		if (c1 != c2) {
			return c1 - c2;
		}
	}

	return (int)(len1 - len2);
}

int timelib_strncasecmp(const char *s1, const char *s2, size_t length)
{
	size_t len;
	size_t len1 = strlen(s1);
	size_t len2 = strlen(s2);
	int c1, c2;

	if (s1 == s2) {
		return 0;
	}
	len = MIN(length, MIN(len1, len2));
	while (len--) {
		c1 = timelib_tolower(*(unsigned char *)s1++);
		c2 = timelib_tolower(*(unsigned char *)s2++);
		if (c1 != c2) {
			return c1 - c2;
		}
	}

	return (int)(MIN(length, len1) - MIN(length, len2));
}

#undef MIN
#undef MAX

void timelib_dump_date(timelib_time *d, int options)
{
	if ((options & 2) == 2) {
		printf("TYPE: %d ", d->zone_type);
	}
	printf("TS: %lld | %s%04lld-%02lld-%02lld %02lld:%02lld:%02lld",
		d->sse, d->y < 0 ? "-" : "", TIMELIB_LLABS(d->y), d->m, d->d, d->h, d->i, d->s);
	if (d->us > 0) {
		printf(" 0.%06lld", d->us);
	}

	if (d->is_localtime) {
		switch (d->zone_type) {
			case TIMELIB_ZONETYPE_OFFSET: /* Only offset */
				printf(" GMT %05d%s", d->z, d->dst == 1 ? " (DST)" : "");
				break;
			case TIMELIB_ZONETYPE_ID: /* Timezone struct */
				/* Show abbreviation if wanted */
				if (d->tz_abbr) {
					printf(" %s", d->tz_abbr);
				}
				/* Do we have a TimeZone struct? */
				if (d->tz_info) {
					printf(" %s", d->tz_info->name);
				}
				break;
			case TIMELIB_ZONETYPE_ABBR:
				printf(" %s", d->tz_abbr);
				printf(" %05d%s", d->z, d->dst == 1 ? " (DST)" : "");
				break;
		}
	}

	if ((options & 1) == 1) {
		if (d->have_relative) {
			printf("%3lldY %3lldM %3lldD / %3lldH %3lldM %3lldS",
				d->relative.y, d->relative.m, d->relative.d, d->relative.h, d->relative.i, d->relative.s);
			if (d->relative.us) {
				printf(" 0.%06lld", d->relative.us);
			}
			if (d->relative.first_last_day_of != 0) {
				switch (d->relative.first_last_day_of) {
					case 1:
						printf(" / first day of");
						break;
					case 2:
						printf(" / last day of");
						break;
				}
			}
			if (d->relative.have_weekday_relative) {
				printf(" / %d.%d", d->relative.weekday, d->relative.weekday_behavior);
			}
			if (d->relative.have_special_relative) {
				switch (d->relative.special.type) {
					case TIMELIB_SPECIAL_WEEKDAY:
						printf(" / %lld weekday", d->relative.special.amount);
						break;
					case TIMELIB_SPECIAL_DAY_OF_WEEK_IN_MONTH:
						printf(" / x y of z month");
						break;
					case TIMELIB_SPECIAL_LAST_DAY_OF_WEEK_IN_MONTH:
						printf(" / last y of z month");
						break;
				}
			}
		}
	}
	printf("\n");
}

void timelib_dump_rel_time(timelib_rel_time *d)
{
	printf("%3lldY %3lldM %3lldD / %3lldH %3lldM %3lldS (days: %lld)%s",
		d->y, d->m, d->d, d->h, d->i, d->s, d->days, d->invert ? " inverted" : "");
	if (d->first_last_day_of != 0) {
		switch (d->first_last_day_of) {
			case 1:
				printf(" / first day of");
				break;
			case 2:
				printf(" / last day of");
				break;
		}
	}
	printf("\n");
}