/*
 * Copyright (c) 2009 Lukas Mejdrech
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - 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.
 * - The name of the author may not 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 AUTHOR 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.
 */

/** @addtogroup libc
 *  @{
 */

/** @file
 * Internet protocol address conversion functions implementation.
 */

#include <net/socket_codes.h>
#include <net/in.h>
#include <net/in6.h>
#include <net/inet.h>

#include <errno.h>
#include <mem.h>
#include <stdio.h>
#include <str.h>

/** Prints the address into the character buffer.
 *
 *  @param[in] family	The address family.
 *  @param[in] data	The address data.
 *  @param[out] address	The character buffer to be filled.
 *  @param[in] length	The buffer length.
 *  @return		EOK on success.
 *  @return		EINVAL if the data or address parameter is NULL.
 *  @return		ENOMEM if the character buffer is not long enough.
 *  @return		ENOTSUP if the address family is not supported.
 */
int
inet_ntop(uint16_t family, const uint8_t *data, char *address, size_t length)
{
	if ((!data) || (!address))
		return EINVAL;

	switch (family) {
	case AF_INET:
		/* Check output buffer size */
		if (length < INET_ADDRSTRLEN)
			return ENOMEM;
			
		/* Fill buffer with IPv4 address */
		snprintf(address, length, "%hhu.%hhu.%hhu.%hhu",
		    data[0], data[1], data[2], data[3]);

		return EOK;

	case AF_INET6:
		/* Check output buffer size */
		if (length < INET6_ADDRSTRLEN)
			return ENOMEM;
		
		/* Fill buffer with IPv6 address */
		snprintf(address, length,
		    "%hhx%hhx:%hhx%hhx:%hhx%hhx:%hhx%hhx:%hhx%hhx:%hhx%hhx:"
		    "%hhx%hhx:%hhx%hhx",
		    data[0], data[1], data[2], data[3], data[4], data[5],
		    data[6], data[7], data[8], data[9], data[10], data[11],
		    data[12], data[13], data[14], data[15]);
		
		return EOK;

	default:
		return ENOTSUP;
	}
}

/** Parses the character string into the address.
 *
 *  If the string is shorter than the full address, zero bytes are added.
 *
 *  @param[in] family	The address family.
 *  @param[in] address	The character buffer to be parsed.
 *  @param[out] data	The address data to be filled.
 *  @return		EOK on success.
 *  @return		EINVAL if the data parameter is NULL.
 *  @return		ENOENT if the address parameter is NULL.
 *  @return		ENOTSUP if the address family is not supported.
 */
int inet_pton(uint16_t family, const char *address, uint8_t *data)
{
	/** The base number of the values. */
	int base;
	/** The number of bytes per a section. */
	size_t bytes;
	/** The number of bytes of the address data. */
	int count;

	const char *next;
	char *last;
	int index;
	size_t shift;
	unsigned long value;

	if (!data)
		return EINVAL;

	/* Set processing parameters */
	switch (family) {
	case AF_INET:
		count = 4;
		base = 10;
		bytes = 1;
		break;

	case AF_INET6:
		count = 16;
		base = 16;
		bytes = 4;
		break;

	default:
		return ENOTSUP;
	}

	/* Erase if no address */
	if (!address) {
		bzero(data, count);
		return ENOENT;
	}

	/* Process string from the beginning */
	next = address;
	index = 0;
	do {
		/* If the actual character is set */
		if (next && *next) {

			/* If not on the first character */
			if (index) {
				/* Move to the next character */
				++next;
			}

			/* Parse the actual integral value */
			value = strtoul(next, &last, base);
			/*
			 * Remember the last problematic character
			 * should be either '.' or ':' but is ignored to be
			 * more generic
			 */
			next = last;

			/* Fill the address data byte by byte */
			shift = bytes - 1;
			do {
				/* like little endian */
				data[index + shift] = value;
				value >>= 8;
			} while(shift --);

			index += bytes;
		} else {
			/* Erase the rest of the address */
			bzero(data + index, count - index);
			return EOK;
		}
	} while (index < count);

	return EOK;
}

/** @}
 */