/**

 * @file enc_csv.c

 * Encoder for CSV format. Note: CEE currently think about what a

 * CEE-compliant CSV format may look like. As such, the format of

 * this output will most probably change once the final decision

 * has been made. At this time (2010-12), I do NOT even try to

 * stay inline with the discussion.

 *

 * This file contains code from all related objects that is required in

 * order to encode this format. The core idea of putting all of this into

 * a single file is that this makes it very straightforward to write

 * encoders for different encodings, as all is in one place.

 *

 */

/*

 * liblognorm - a fast samples-based log normalization library

 * Copyright 2010-2018 by Rainer Gerhards and Adiscon GmbH.

 *

 * Modified by Pavel Levshin (pavel@levshin.spb.ru) in 2013

 *

 * This file is part of liblognorm.

 *

 * This library is free software; you can redistribute it and/or

 * modify it under the terms of the GNU Lesser General Public

 * License as published by the Free Software Foundation; either

 * version 2.1 of the License, or (at your option) any later version.

 *

 * This library 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

 * Lesser General Public License for more details.

 *

 * You should have received a copy of the GNU Lesser General Public

 * License along with this library; if not, write to the Free Software

 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA

 *

 * A copy of the LGPL v2.1 can be found in the file "COPYING" in this distribution.

 */

#include "config.h"

#include <stdlib.h>

#include <stdio.h>

#include <stdarg.h>

#include <assert.h>

#include <string.h>

#include <libestr.h>

#include "lognorm.h"

#include "internal.h"

#include "enc.h"

static char hexdigit[16] =

	{'0', '1', '2', '3', '4', '5', '6', '7', '8',

	 '9', 'A', 'B', 'C', 'D', 'E', 'F' };

/* TODO: CSV encoding for Unicode characters is as of RFC4627 not fully

 * supported. The algorithm is that we must build the wide character from

 * UTF-8 (if char > 127) and build the full 4-octet Unicode character out

 * of it. Then, this needs to be encoded. Currently, we work on a

 * byte-by-byte basis, which simply is incorrect.

 * rgerhards, 2010-11-09

 */

static int

ln_addValue_CSV(const char *buf, es_str_t **str)

{

	int r;

	unsigned char c;

	es_size_t i;

	char numbuf[4];

	int j;

	assert(str != NULL);

	assert(*str != NULL);

	assert(buf != NULL);

	for(i = 0; i < strlen(buf); i++) {

		c = buf[i];

		if((c >= 0x23 && c <= 0x5b)

		   || (c >= 0x5d /* && c <= 0x10FFFF*/)

		   || c == 0x20 || c == 0x21) {

			/* no need to escape */

			es_addChar(str, c);

		} else {

			/* we must escape, try RFC4627-defined special sequences first */

			switch(c) {

			case '\0':

				es_addBuf(str, "\\u0000", 6);

				break;

			case '\"':

				es_addBuf(str, "\\\"", 2);

				break;

			case '\\':

				es_addBuf(str, "\\\\", 2);

				break;

			case '\010':

				es_addBuf(str, "\\b", 2);

				break;

			case '\014':

				es_addBuf(str, "\\f", 2);

				break;

			case '\n':

				es_addBuf(str, "\\n", 2);

				break;

			case '\r':

				es_addBuf(str, "\\r", 2);

				break;

			case '\t':

				es_addBuf(str, "\\t", 2);

				break;

			default:

				/* TODO : proper Unicode encoding (see header comment) */

				for(j = 0 ; j < 4 ; ++j) {

					numbuf[3-j] = hexdigit[c % 16];

					c = c / 16;

				}

				es_addBuf(str, "\\u", 2);

				es_addBuf(str, numbuf, 4);

				break;

			}

		}

	}

	r = 0;

	return r;

}

static int

ln_addField_CSV(struct json_object *field, es_str_t **str)

{

	int r, i;

	struct json_object *obj;

	int needComma = 0;

	const char *value;

	assert(field != NULL);

	assert(str != NULL);

	assert(*str != NULL);

	switch(json_object_get_type(field)) {

	case json_type_array:

		CHKR(es_addChar(str, '['));

		for (i = json_object_array_length(field) - 1; i >= 0; i--) {

			if(needComma)

				es_addChar(str, ',');

			else

				needComma = 1;

			CHKN(obj = json_object_array_get_idx(field, i));

			CHKN(value = json_object_get_string(obj));

			CHKR(ln_addValue_CSV(value, str));

		}

		CHKR(es_addChar(str, ']'));

		break;

	case json_type_string:

	case json_type_int:

		CHKN(value = json_object_get_string(field));

		CHKR(ln_addValue_CSV(value, str));

		break;

	case json_type_null:

	case json_type_boolean:

	case json_type_double:

	case json_type_object:

		CHKR(es_addBuf(str, "***unsupported type***", sizeof("***unsupported type***")-1));

		break;

	default:

		CHKR(es_addBuf(str, "***OBJECT***", sizeof("***OBJECT***")-1));

	}

	r = 0;

done:

	return r;

}

int

ln_fmtEventToCSV(struct json_object *json, es_str_t **str, es_str_t *extraData)

{

	int r = -1;

	int needComma = 0;

	struct json_object *field;

	char *namelist = NULL, *name, *nn;

	assert(json != NULL);

	assert(json_object_is_type(json, json_type_object));

	if((*str = es_newStr(256)) == NULL)

		goto done;

	if(extraData == NULL)

		goto done;

	CHKN(namelist = es_str2cstr(extraData, NULL));

	for (name = namelist; name != NULL; name = nn) {

		for (nn = name; *nn != '\0' && *nn != ',' && *nn != ' '; nn++)

			{ /* do nothing */ }

		if (*nn == '\0') {

			nn = NULL;

		} else {

			*nn = '\0';

			nn++;

		}

		json_object_object_get_ex(json, name, &field);

		if (needComma) {

			CHKR(es_addChar(str, ','));

		} else {

			needComma = 1;

		}

		if (field != NULL) {

			CHKR(es_addChar(str, '"'));

			ln_addField_CSV(field, str);

			CHKR(es_addChar(str, '"'));

		}

	}

	r = 0;

done:

	if (namelist != NULL)

		free(namelist);

	return r;

}