/*
 * Copyright 2017 Yann Weber
 * 
 * This file is part of Ttail.
 * 
 * Ttail is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * any later version.
 * 
 * Ttail 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 General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with Ttail.  If not, see <http://www.gnu.org/licenses/>.
 */
#include "ttail_search.h"

int ttail_search_init_session(ttail_t* ttail)
{
	if(ttail->session != NULL)
	{
		fprintf(stderr, "A session is allready started\n");
		return -1;
	}
	return ttail->logfile_sz?\
		ttail_search_files_init(ttail):\
		ttail_search_std_init(ttail);
}

int ttail_search_closest(ttail_t* ttail)
{
	int ret;
	if(ttail->session == NULL)
	{
		fprintf(stderr, "No session started yet\n");
		return -1;
	}
	ret = ttail->logfile_sz?\
		_ttail_search_closest_files(ttail):\
		_ttail_search_closest_stdin(ttail);
	if(ret < 0)
	{
		return -1;
	}
	if(ret > 0)
	{
		return ret;
	}
	return 0;
}

void ttail_search_print_res(ttail_t* t)
{
	if(t->logfile_sz)
	{
		_ttail_search_print_files(t, 1);
		_ttail_search_file_free(t);
	}
	else
	{
		_ttail_search_print_stdin(t, 1);
		_ttail_search_stdin_free(t);
	}
}

int ttail_logline2date(ttail_t* ttail, const char* logline, struct tm* tm)
{
	const char *subst, *ret;

	ttail_tm_init(tm);
	
	if(ttail->flag & TTAIL_FLAG_PREFIX)
	{
		subst = ttail_logline_subst(ttail, logline);
		if(!subst)
		{
			memset(tm, 0,sizeof(struct tm));
			return 1;
		}
	}
	else
	{
		subst = logline;
	}
	ret = strptime(subst, ttail->fmt, tm);
	if(!ret)
	{
		memset(tm, 0,sizeof(struct tm));
		return 2;
	}
	return 0;
}

const char* ttail_logline_subst(ttail_t* t, const char* logline)
{
	regmatch_t pmatch[1];
	size_t nmatch;
	int ret;
	char err[1024];
	
	if(!t->prefix_sz)
	{
		return logline;
	}
	else if(t->prefix_sz > 0)
	{
		/* constant subst */
		return strlen(logline) < t->prefix_sz ? \
			NULL:logline + t->prefix_sz;
	}
	/* regex subst */
	nmatch=1;
	ret = regexec(&(t->date_prefix), logline, nmatch, pmatch, 0);
	if(ret)
	{
		regerror(ret, &(t->date_prefix), err,1024);
		fprintf(stderr, "RegEx exec error : %s\n", err);
		return NULL;
	}
	return logline + pmatch[0].rm_eo;
}

int ttail_tm_cmp(const struct tm *ta, const struct tm *tb)
{
	int r;
	r=0;
	if(ta->tm_year >= 0 && tb->tm_year >= 0)
	{
		r = ta->tm_year - tb->tm_year;
		if(r) { return r; }
	}
	if(ta->tm_mon >= 0 && tb->tm_mon >= 0)
	{
		r = ta->tm_mon - tb->tm_mon;
		if(r) { return r; }
	}
	if(ta->tm_mday >= 0 && tb->tm_mday >= 0)
	{
		r = ta->tm_mday - tb->tm_mday;
		if(r) { return r; }
	}
	if(ta->tm_hour >= 0 && tb->tm_hour >= 0)
	{
		r = ta->tm_hour - tb->tm_hour;
		if(r) { return r; }
	}
	if(ta->tm_min >= 0 && tb->tm_min >= 0)
	{
		r = ta->tm_min - tb->tm_min;
		if(r) { return r; }
	}
	if(ta->tm_sec >= 0 && tb->tm_sec >= 0)
	{
		r = ta->tm_sec - tb->tm_sec;
	}
	return r;
}

void ttail_tm_init(struct tm* tm)
{
	size_t i;
	int *ptr;
	ptr = (int*)tm;
	for(i=0; i<sizeof(struct tm)/sizeof(int); i++)
	{
		*ptr = -1;
		ptr++;
	}
}

void ttail_tm_print(const struct tm* tm)
{
	printf("year:%d month:%d mday:%d hour:%d min:%d sec:%d",
		tm->tm_year, tm->tm_mon, tm->tm_mday, tm->tm_hour, tm->tm_min,
		tm->tm_sec);
}

void ttail_tm_fprint(FILE *stream, const struct tm* tm)
{
	if(tm->tm_year >= 0)
	{
		fprintf(stream, "year : %d ", tm->tm_year + 1900);
	}
	if(tm->tm_mon >= 0)
	{
		fprintf(stream, "month : %d ", tm->tm_mon);
	}
	if(tm->tm_mday >= 0)
	{
		fprintf(stream, "day : %d ", tm->tm_mday);
	}
	if(tm->tm_hour >= 0)
	{
		fprintf(stream, "hour : %d ", tm->tm_hour);
	}
	if(tm->tm_min >= 0)
	{
		fprintf(stream, "minute : %d ", tm->tm_min);
	}
	if(tm->tm_sec >= 0)
	{
		fprintf(stream, "secs : %d ", tm->tm_sec);
	}
}