/* $Id: helper.c,v 1.6 2012/10/16 03:22:06 khorben Exp $ */
/* Copyright (c) 2012 Pierre Pronchery <khorben@defora.org> */
/* This file is part of DeforaOS Desktop Mailer */
/* This program 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, version 3 of the License.
 *
 * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>. */



#include <ctype.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "../include/Mailer/helper.h"


/* public */
/* functions */
/* mailer_helper_get_email */
char * mailer_helper_get_email(char const * header)
{
	char * ret;
	size_t len;
	char * buf = NULL;

	if(header == NULL)
		return NULL;
	len = strlen(header);
	if((ret = malloc(len + 1)) == NULL || (buf = malloc(len + 1)) == NULL)
	{
		free(buf);
		free(ret);
		return NULL;
	}
	if(mailer_helper_is_email(header))
	{
		strcpy(ret, header);
		free(buf);
		return ret;
	}
	if(sscanf(header, "%[^(](%[^)])", ret, buf) == 2
			|| sscanf(header, "<%[^>]>", ret) == 1
			|| sscanf(header, "%[^<]<%[^>]>", buf, ret) == 2)
	{
		for(len = strlen(ret); len > 0 && isblank(ret[len - 1]); len--)
			ret[len - 1] = '\0';
		if(mailer_helper_is_email(ret))
		{
			free(buf);
			return ret;
		}
	}
	free(buf);
	free(ret);
	return NULL;
}


/* mailer_helper_get_name */
char * mailer_helper_get_name(char const * header)
{
	char * ret;
	size_t len;
	char * buf = NULL;
	int c;

	if(header == NULL)
		return NULL;
	len = strlen(header);
	if((ret = malloc(len + 1)) == NULL || (buf = malloc(len + 1)) == NULL)
	{
		free(buf);
		free(ret);
		return NULL;
	}
	if(mailer_helper_is_email(header))
	{
		strcpy(ret, header);
		free(buf);
		return ret;
	}
	if(sscanf(header, "%[^(](%[^)])", buf, ret) != 2
			&& sscanf(header, "<%[^>]>", ret) != 1
			&& sscanf(header, "%[^<]<%[^>]>", ret, buf) != 2)
	{
		free(buf);
		free(ret);
		return NULL;
	}
	free(buf);
	/* right-trim spaces */
	for(len = strlen(ret); --len > 0 && isspace((c = ret[len]));
			ret[len] = '\0');
	/* remove surrounding quotes */
	if((len = strlen(ret)) >= 2 && ((c = ret[0]) == '"' || c == '\'')
			&& ret[len - 1] == c)
	{
		memmove(ret, &ret[1], len - 2);
		ret[len - 2] = '\0';
	}
	return ret;
}


/* mailer_helper_is_email */
int mailer_helper_is_email(char const * header)
{
	size_t i = 0;
	int c;

	/* FIXME this is neither strict nor standard at the moment */
	for(i = 0; (c = header[i]) != '@'; i++)
		if(c == '\0')
			return 0;
		else if(!isalnum(c) && c != '.' && c != '_')
			return 0;
	for(i++; (c = header[i]) != '\0'; i++)
		if(!isalnum(c) && c != '.' && c != '_')
			return 0;
	return 1;
}