/*** dt-core-strpf.c -- parser and formatter funs for dt-core
 *
 * Copyright (C) 2011-2016 Sebastian Freundt
 *
 * Author:  Sebastian Freundt <freundt@ga-group.nl>
 *
 * This file is part of dateutils.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 *
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * 3. Neither the name of the author nor the names of any contributors
 *    may be used to endorse or promote products derived from this
 *    software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
 * BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
 * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 **/
/* implementation part of date-core-strpf.h */
#if !defined INCLUDED_dt_core_strpf_c_
#define INCLUDED_dt_core_strpf_c_

#if defined HAVE_CONFIG_H
# include "config.h"
#endif	/* HAVE_CONFIG_H */
#include "strops.h"
#include "token.h"
#include "dt-core.h"
#include "dt-core-strpf.h"

#if defined __INTEL_COMPILER
/* we MUST return a char* */
# pragma warning (disable:2203)
#elif defined __GNUC__
# pragma GCC diagnostic ignored "-Wcast-qual"
#endif	/* __INTEL_COMPILER */

#if !defined DEFUN
# define DEFUN
#endif	/* !DEFUN */

#if defined SKIP_LEAP_ARITH
# undef WITH_LEAP_SECONDS
#endif	/* SKIP_LEAP_ARITH */

static int32_t
try_zone(const char *str, const char **ep)
{
	int minusp = 0;
	const char *sp = str;
	int32_t res = 0;

	switch (*sp) {
		int32_t tmp;
		const char *tp;
		const char *up;
	case '-':
		minusp = 1;
	case '+':
		/* read hour part */
		if ((tmp = strtoi_lim(sp + 1U, &tp, 0, 14)) < 0) {
			break;
		} else if (tp - sp < 3U) {
			/* only accept fully zero-padded hours */
			break;
		}
		res += 3600 * tmp;
		/* colon separator is optional */
		if (*tp == ':') {
			tp++;
		}

		/* read minute part */
		if ((tmp = strtoi_lim(tp, &up, 0, 59)) < 0) {
			break;
		} else if (up - tp < 2U) {
			/* only accept zero-padded minutes */
			break;
		} else {
			tp = up;
		}
		res += 60 * tmp;
		/* at least we've got hours and minutes */
		sp = tp;
		/* again colon separator is optional */
		if (*tp == ':') {
			tp++;
		}

		/* read second part */
		if ((tmp = strtoi_lim(tp, &tp, 0, 59)) < 0) {
			break;
		}
		res += tmp;
		/* fully determined */
		sp = tp;
		break;
	case 'Z':
		/* accept Zulu specifier */
		sp++;
		break;
	default:
		/* clearly a mistake to advance SP */
		break;
	}
	/* res.typ coincides with DT_SANDWICH_D_ONLY() if we jumped here */
	if (ep != NULL) {
		*ep = sp;
	}
	return minusp ? -res : res;
}

static struct dt_dt_s
__fixup_zdiff(struct dt_dt_s dt, int32_t zdiff)
{
/* apply time zone difference */
	/* reuse dt for result */
#if defined HAVE_ANON_STRUCTS_INIT
	dt = dt_dtadd(dt, (struct dt_dtdur_s){DT_DURS, .dv = -zdiff});
#else
	{
		struct dt_dtdur_s tmp = {DT_DURS};
		tmp.dv = -zdiff;
		dt = dt_dtadd(dt, tmp);
	}
#endif
	dt.znfxd = 1;
	return dt;
}

DEFUN struct dt_dt_s
__strpdt_std(const char *str, char **ep)
{
/* code dupe, see __strpd_std() */
	struct dt_dt_s res = dt_dt_initialiser();
	struct strpdt_s d = strpdt_initialiser();
	const char *sp;

	if ((sp = str) == NULL) {
		goto out;
	}
	/* check for epoch notation */
	if (*sp == '@') {
		/* yay, epoch */
		const char *tmp;
		d.i = strtoi(++sp, &tmp);
		if (UNLIKELY(d.i == -1 && sp == tmp)) {
			sp--;
		} else {
			/* let's make a DT_SEXY */
			res.typ = DT_SEXY;
			res.sxepoch = d.i;
		}
		goto out;
	}
	with (char *tmp) {
		/* let date-core do the hard yakka */
		if ((res.d = __strpd_std(str, &tmp)).typ == DT_DUNK) {
			/* not much use parsing on */
			goto try_time;
		}
		sp = tmp;
	}
	/* check for the d/t separator */
	switch (*sp) {
	case 'T':
	case ' ':
	case '\t':
		/* could be a time, could be something, else
		 * make sure we leave a mark */
		str = sp++;
		break;
	default:
		/* should be a no-op */
		dt_make_d_only(&res, res.d.typ);
		goto out;
	}
try_time:
	/* and now parse the time */
	if ((d.st.h = strtoi_lim(sp, &sp, 0, 24)) < 0 ||
	    *sp != ':') {
		sp = str;
		goto out;
	} else if ((d.st.m = strtoi_lim(++sp, &sp, 0, 59)) < 0) {
		d.st.m = 0;
		goto out;
	} else if (*sp != ':') {
		goto eval_time;
	} else if ((d.st.s = strtoi_lim(++sp, &sp, 0, 60)) < 0) {
		d.st.s = 0;
	} else if (*sp != '.') {
		goto eval_time;
	} else if ((d.st.ns = strtoi_lim(++sp, &sp, 0, 999999999)) < 0) {
		d.st.ns = 0;
		goto eval_time;
	}
eval_time:
	if (UNLIKELY(d.st.h == 24)) {
		if (d.st.m || d.st.s || d.st.ns) {
			sp = str;
			goto out;
		}
	}
	res.t.hms.h = d.st.h;
	res.t.hms.m = d.st.m;
	res.t.hms.s = d.st.s;
	if (res.d.typ > DT_DUNK) {
		const char *tp;
		dt_make_sandwich(&res, res.d.typ, DT_HMS);
		/* check for the zone stuff */
		if ((d.zdiff = try_zone(sp, &tp))) {
			res = __fixup_zdiff(res, d.zdiff);
		} else if (tp > sp) {
			res.znfxd = 1U;
		}
		sp = tp;
	} else {
		dt_make_t_only(&res, DT_HMS);
	}
out:
	/* res.typ coincides with DT_SANDWICH_D_ONLY() if we jumped here */
	if (ep != NULL) {
		*ep = (char*)sp;
	}
	return res;
}

DEFUN int
__strpdt_card(struct strpdt_s *d, const char *sp, struct dt_spec_s s, char **ep)
{
	int res = 0;

	switch (s.spfl) {
	default:
	case DT_SPFL_UNK:
		res = -1;
		break;
	case DT_SPFL_N_DSTD:
	case DT_SPFL_N_YEAR:
	case DT_SPFL_N_MON:
	case DT_SPFL_N_DCNT_MON:
	case DT_SPFL_N_DCNT_WEEK:
	case DT_SPFL_N_DCNT_YEAR:
	case DT_SPFL_N_WCNT_MON:
	case DT_SPFL_N_WCNT_YEAR:
	case DT_SPFL_S_WDAY:
	case DT_SPFL_S_MON:
	case DT_SPFL_S_QTR:
	case DT_SPFL_N_QTR:
		res = __strpd_card(&d->sd, sp, s, ep);
		goto out_direct;

	case DT_SPFL_N_TSTD:
	case DT_SPFL_N_HOUR:
	case DT_SPFL_N_MIN:
	case DT_SPFL_N_SEC:
	case DT_SPFL_N_NANO:
	case DT_SPFL_S_AMPM:
		res = __strpt_card(&d->st, sp, s, ep);
		goto out_direct;

	case DT_SPFL_N_EPOCH:
		/* read over @ */
		if (UNLIKELY(*sp == '@')) {
			sp++;
		}
		d->i = strtoi(sp, &sp);
		break;

	case DT_SPFL_N_ZDIFF: {
		const char *tp;
		if ((d->zdiff = try_zone(sp, &tp)) || tp > sp) {
			d->zngvn = 1;
		}
		sp = tp;
		break;
	}

	case DT_SPFL_LIT_PERCENT:
		if (*sp++ != '%') {
			res = -1;
		}
		break;
	case DT_SPFL_LIT_TAB:
		if (*sp++ != '\t') {
			res = -1;
		}
		break;
	case DT_SPFL_LIT_NL:
		if (*sp++ != '\n') {
			res = -1;
		}
		break;
	}
	/* assign end pointer */
	if (ep != NULL) {
		*ep = (char*)sp;
	}
out_direct:
	return res;
}

DEFUN size_t
__strfdt_card(
	char *buf, size_t bsz, struct dt_spec_s s,
	struct strpdt_s *d, struct dt_dt_s that)
{
	size_t res = 0;

	switch (s.spfl) {
	default:
	case DT_SPFL_UNK:
		break;
	case DT_SPFL_N_DSTD:
	case DT_SPFL_N_YEAR:
	case DT_SPFL_N_MON:
	case DT_SPFL_N_DCNT_WEEK:
	case DT_SPFL_N_DCNT_MON:
	case DT_SPFL_N_DCNT_YEAR:
	case DT_SPFL_N_WCNT_MON:
	case DT_SPFL_N_WCNT_YEAR:
	case DT_SPFL_S_WDAY:
	case DT_SPFL_S_MON:
	case DT_SPFL_S_QTR:
	case DT_SPFL_N_QTR:
		res = __strfd_card(buf, bsz, s, &d->sd, that.d);
		break;

	case DT_SPFL_N_TSTD:
	case DT_SPFL_N_HOUR:
	case DT_SPFL_N_MIN:
	case DT_SPFL_N_SEC:
	case DT_SPFL_S_AMPM:
	case DT_SPFL_N_NANO:
		res = __strft_card(buf, bsz, s, &d->st, that.t);
		break;

	case DT_SPFL_N_EPOCH: {
		/* convert to sexy */
		int64_t sexy = dt_conv_to_sexy(that).sexy;
		res = snprintf(buf, bsz, "%" PRIi64, sexy);
		break;
	}

	case DT_SPFL_N_ZDIFF: {
		int32_t z = d->zdiff;
		char sign = '+';

		if (z < 0) {
			z = -z;
			sign = '-';
		}
		res = snprintf(
			buf, bsz, "%c%02u:%02u",
			sign, (uint32_t)z / 3600U, ((uint32_t)z / 60U) % 60U);
		break;
	}

	case DT_SPFL_LIT_PERCENT:
		/* literal % */
		buf[res++] = '%';
		break;
	case DT_SPFL_LIT_TAB:
		/* literal tab */
		buf[res++] = '\t';
		break;
	case DT_SPFL_LIT_NL:
		/* literal \n */
		buf[res++] = '\n';
		break;
	}
	return res;
}

DEFUN size_t
__strfdt_dur(
	char *buf, size_t bsz, struct dt_spec_s s,
	struct strpdt_s *d, struct dt_dtdur_s that)
{
	switch (s.spfl) {
	default:
	case DT_SPFL_UNK:
		return 0;

	case DT_SPFL_N_DSTD:
	case DT_SPFL_N_YEAR:
	case DT_SPFL_N_MON:
	case DT_SPFL_N_DCNT_WEEK:
	case DT_SPFL_N_DCNT_MON:
	case DT_SPFL_N_DCNT_YEAR:
	case DT_SPFL_N_WCNT_MON:
	case DT_SPFL_N_WCNT_YEAR:
	case DT_SPFL_S_WDAY:
	case DT_SPFL_S_MON:
	case DT_SPFL_S_QTR:
	case DT_SPFL_N_QTR:
		return __strfd_dur(buf, bsz, s, &d->sd, that.d);

		/* noone's ever bothered doing the same thing for times */
	case DT_SPFL_N_TSTD:
	case DT_SPFL_N_SEC:;
		int64_t dv;

		dv = that.dv;
		switch (that.durtyp) {
		default:
			if (that.d.durtyp != DT_DURD) {
				return 0U;
			}
			dv = (int64_t)that.d.dv * HOURS_PER_DAY;
			/*@fallthrough@*/
		case DT_DURH:
			dv *= MINS_PER_HOUR;
			/*@fallthrough@*/
		case DT_DURM:
			dv *= SECS_PER_MIN;
			/*@fallthrough@*/
		case DT_DURS:
			if (LIKELY(!that.tai)) {
				return (size_t)snprintf(
					buf, bsz, "%" PRIi64 "s", dv);
			} else {
				return (size_t)snprintf(
					buf, bsz, "%" PRIi64 "rs", dv);
			}
			break;
		}
		break;

	case DT_SPFL_N_NANO: {
		int64_t dur = that.dv;

		switch (that.durtyp) {
		case DT_DURS:
			dur *= NANOS_PER_SEC;
			/*@fallthrough@*/
		case DT_DURNANO:
			if (LIKELY(!that.tai)) {
				return (size_t)snprintf(
					buf, bsz, "%" PRIi64 "ns", dur);
			} else {
				return (size_t)snprintf(
					buf, bsz, "%" PRIi64 "rns", dur);
			}
		default:
			break;
		}
		break;
	}

	case DT_SPFL_LIT_PERCENT:
		/* literal % */
		*buf = '%';
		break;
	case DT_SPFL_LIT_TAB:
		/* literal tab */
		*buf = '\t';
		break;
	case DT_SPFL_LIT_NL:
		/* literal \n */
		*buf = '\n';
		break;
	}
	return 1;
}

static size_t
__strfdt_xdn(char *buf, size_t bsz, struct dt_dt_s that)
{
	double dn;

	switch (that.d.typ) {
	case DT_JDN:
		dn = (double)that.d.jdn;
		break;
	case DT_LDN:
		dn = (double)that.d.ldn;
		if (dt_sandwich_only_d_p(that)) {
			return snprintf(buf, bsz, "%.0f", dn);
		}
		break;
	default:
		return 0;
	}

	if (dt_sandwich_p(that)) {
		unsigned int ss = __secs_since_midnight(that.t);
		dn += (double)ss / (double)SECS_PER_DAY;
	}
	return snprintf(buf, bsz, "%.6f", dn);
}

#endif	/* INCLUDED_dt_core_strpf_c_ */
