/*
     This file is part of GNUnet
     (C) 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009 Christian Grothoff (and other contributing authors)

     GNUnet 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, or (at your
     option) any later version.

     GNUnet 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 GNUnet; see the file COPYING.  If not, write to the
     Free Software Foundation, Inc., 59 Temple Place - Suite 330,
     Boston, MA 02111-1307, USA.
*/

/**
 * @file transport/plugin_transport_http_common.c
 * @brief functionality shared by http client and server transport service plugin
 * @author Matthias Wachs
 */
#include "platform.h"
#include "gnunet_util_lib.h"
#include "gnunet_transport_plugin.h"
#include "plugin_transport_http_common.h"

struct SplittedHTTPAddress
{
	char *protocol;
	char *host;
	char *path;
	int port;
};


static void
http_clean_splitted (struct SplittedHTTPAddress *spa)
{
  if (NULL != spa)
  {
    GNUNET_free_non_null (spa->protocol);
    GNUNET_free_non_null (spa->host);
    GNUNET_free_non_null (spa->path);
    GNUNET_free_non_null (spa);
  }
}

struct SplittedHTTPAddress *
http_split_address (const char * addr)
{
	struct SplittedHTTPAddress  *sp;
	char *src = GNUNET_strdup (addr);
	char *protocol_start = NULL;
	char *host_start = NULL;
	char *v6_end = NULL;
	char *port_start = NULL;
	char *path_start = NULL;
	protocol_start = src;
	sp = GNUNET_malloc (sizeof (struct SplittedHTTPAddress));

	/* Address string consists of protocol://host[:port]path*/

	host_start = strstr (src, "://");
	if (NULL == host_start)
	{
			GNUNET_free (src);
			GNUNET_free (sp);
			return NULL;
	}

	host_start[0] = '\0';
	sp->protocol = GNUNET_strdup (protocol_start);

	host_start += strlen ("://");
	if (strlen (host_start) == 0)
	{
			GNUNET_free (src);
			GNUNET_free (sp->protocol);
			GNUNET_free (sp);
			return NULL;
	}

	/* Find path start */
	path_start = strchr (host_start, '/');
	if (NULL != path_start)
	{
			sp->path = GNUNET_strdup (path_start);
			path_start[0] = '\0';
	}
	else
		sp->path = GNUNET_strdup ("");

	if (strlen(host_start) < 1)
	{
			GNUNET_free (src);
			GNUNET_free (sp->protocol);
			GNUNET_free (sp->path);
			GNUNET_free (sp);
			return NULL;
	}

	if (NULL != (port_start = strrchr (host_start, ':')))
	{
			/* *We COULD have a port, but also an IPv6 address! */
			if (NULL != (v6_end = strchr(host_start, ']')))
			{
					if  (v6_end < port_start)
					{
							/* IPv6 address + port */
							port_start[0] = '\0';
							port_start ++;
							sp->port = atoi (port_start);
							if ((0 == sp->port) || (65535 < sp->port))
							{
								GNUNET_free (src);
								GNUNET_free (sp->protocol);
								GNUNET_free (sp->path);
								GNUNET_free (sp);
								return NULL;
							}
					}
					else
					{
							/* IPv6 address + no port */
							if (0 == strcmp(sp->protocol, "https"))
								sp->port = HTTPS_DEFAULT_PORT;
							else if (0 == strcmp(sp->protocol, "http"))
								sp->port = HTTP_DEFAULT_PORT;
					}
			}
			else
			{
					/* No IPv6 address */
					port_start[0] = '\0';
					port_start ++;
					sp->port = atoi (port_start);
					if ((0 == sp->port) || (65535 < sp->port))
					{
						GNUNET_free (src);
						GNUNET_free (sp->protocol);
						GNUNET_free (sp->path);
						GNUNET_free (sp);
						return NULL;
					}
			}
	}
	else
	{
		/* No ':' as port separator, default port for protocol */
		if (0 == strcmp(sp->protocol, "https"))
			sp->port = HTTPS_DEFAULT_PORT;
		else if (0 == strcmp(sp->protocol, "http"))
			sp->port = HTTP_DEFAULT_PORT;
		else
		{
				GNUNET_break (0);
				GNUNET_free (src);
				GNUNET_free (sp->protocol);
				GNUNET_free (sp->path);
				GNUNET_free (sp);
				return NULL;
		}
	}
	if (strlen (host_start) > 0)
			sp->host = GNUNET_strdup (host_start);
	else
	{
			GNUNET_break (0);
			GNUNET_free (src);
			GNUNET_free (sp->protocol);
			GNUNET_free (sp->path);
			GNUNET_free (sp);
			return NULL;
	}
	GNUNET_free (src);
	return sp;
}

/**
 * Convert the transports address to a nice, human-readable
 * format.
 *
 * @param cls closure
 * @param type name of the transport that generated the address
 * @param addr one of the addresses of the host, NULL for the last address
 *        the specific address format depends on the transport
 * @param addrlen length of the address
 * @param numeric should (IP) addresses be displayed in numeric form?
 * @param timeout after how long should we give up?
 * @param asc function to call on each string
 * @param asc_cls closure for asc
 */
void
http_common_plugin_address_pretty_printer (void *cls, const char *type,
                                        const void *addr, size_t addrlen,
                                        int numeric,
                                        struct GNUNET_TIME_Relative timeout,
                                        GNUNET_TRANSPORT_AddressStringCallback
                                        asc, void *asc_cls)
{
	const struct HttpAddress *address = addr;

  if (NULL == http_common_plugin_address_to_string (NULL, (char *) type, address, addrlen))
  {
      asc (asc_cls, NULL);
      return;
  }
  asc (asc_cls, http_common_plugin_address_to_string (NULL, (char *) type, address, addrlen));
  asc (asc_cls, NULL);
}

const char *
http_common_plugin_address_to_url (void *cls, const void *addr, size_t addrlen)
{
  static char rbuf[1024];
	const struct HttpAddress *address = addr;
  const char * addr_str;



  if (NULL == addr)
  {
  	GNUNET_break (0);
    return NULL;
  }
  if (0 >= addrlen)
  {
  	GNUNET_break (0);
    return NULL;
  }
  if (addrlen != http_common_address_get_size (address))
  {
  	GNUNET_break (0);
    return NULL;
  }
  addr_str = (char *) &address[1];

  if (addr_str[ntohl(address->urlen) -1] != '\0')
    return NULL;

  memcpy (rbuf, &address[1], ntohl(address->urlen));
  return rbuf;
}

/**
 * Function called for a quick conversion of the binary address to
 * a numeric address.  Note that the caller must not free the
 * address and that the next call to this function is allowed
 * to override the address again.
 *
 * @param cls closure
 * @param plugin the plugin
 * @param addr binary address
 * @param addrlen length of the address
 * @return string representing the same address
 */
const char *
http_common_plugin_address_to_string (void *cls, char *plugin, const void *addr, size_t addrlen)
{
  static char rbuf[1024];
	const struct HttpAddress *address = addr;
  const char * addr_str;
  char *res;

  GNUNET_assert (NULL != plugin);

  if (NULL == addr)
      return NULL;
  if (0 == addrlen)
    return TRANSPORT_SESSION_INBOUND_STRING;
  if (addrlen != http_common_address_get_size (address))
  	return NULL;
  addr_str = (char *) &address[1];

  if (addr_str[ntohl(address->urlen) -1] != '\0')
    return NULL;
  GNUNET_asprintf (&res, "%s.%u.%s", plugin, ntohl(address->options), &address[1]);
  if (strlen(res) + 1 < 500)
  {
  	memcpy (rbuf, res, strlen(res) + 1);
  	GNUNET_free (res);
  	return rbuf;
  }
  GNUNET_break (0);
	GNUNET_free (res);
	return NULL;
}

/**
 * Function called to convert a string address to
 * a binary address.
 *
 * @param cls closure ('struct Plugin*')
 * @param addr string address
 * @param addrlen length of the address
 * @param buf location to store the buffer
 *        If the function returns GNUNET_SYSERR, its contents are undefined.
 * @param added length of created address
 * @return GNUNET_OK on success, GNUNET_SYSERR on failure
 */
int
http_common_plugin_string_to_address (void *cls,
                        const char *addr,
                        uint16_t addrlen,
                        void **buf,
                        size_t *added)
{
	struct HttpAddress *a;
  char *address;
  char *plugin;
  char *optionstr;
  size_t urlen;
  uint32_t options;

  /* Format protocol.options.address:port */
  address = NULL;
  plugin = NULL;
  optionstr = NULL;
  if ((NULL == addr) || (addrlen == 0))
  {
    GNUNET_break (0);
    return GNUNET_SYSERR;
  }
  if ('\0' != addr[addrlen - 1])
  {
    GNUNET_break (0);
    return GNUNET_SYSERR;
  }
  if (strlen (addr) != addrlen - 1)
  {
    GNUNET_break (0);
    return GNUNET_SYSERR;
  }
  plugin = GNUNET_strdup (addr);
  optionstr = strchr (plugin, '.');
  if (NULL == optionstr)
  {
    GNUNET_break (0);
    GNUNET_free (plugin);
    return GNUNET_SYSERR;
  }
  optionstr[0] = '\0';
  optionstr ++;
  options = atol (optionstr); /* 0 on conversion error, that's ok */
  address = strchr (optionstr, '.');
  if (NULL == address)
  {
    GNUNET_break (0);
    GNUNET_free (plugin);
    return GNUNET_SYSERR;
  }
  address[0] = '\0';
  address ++;
  urlen = strlen (address) + 1;

  a = GNUNET_malloc (sizeof (struct HttpAddress) + urlen);
  a->options = htonl(options);
  a->urlen = htonl(urlen);
  memcpy (&a[1], address, urlen);

  (*buf) = a;
  (*added) = sizeof (struct HttpAddress) + urlen;
  GNUNET_free (plugin);
  return GNUNET_OK;
}

/**
 * Create a HTTP address from a socketaddr
 *
 * @param protocol protocol
 * @param addr sockaddr * address
 * @param addrlen length of the address
 * @return the HttpAddress
 */
struct HttpAddress *
http_common_address_from_socket (const char *protocol, const struct sockaddr *addr, socklen_t addrlen)
{
  struct HttpAddress *address = NULL;
  char *res;
  size_t len;

  GNUNET_asprintf(&res, "%s://%s", protocol, GNUNET_a2s (addr, addrlen));
  len = strlen (res)+1;

  address = GNUNET_malloc (sizeof (struct HttpAddress) + len);
  address->options = htonl (HTTP_OPTIONS_NONE);
  address->urlen = htonl (len);
  memcpy (&address[1], res, len);
  GNUNET_free (res);

  return address;
}

/**
 * Create a socketaddr from a HTTP address
 *
 * @param addr sockaddr * address
 * @param addrlen length of the address
 * @param res the result:
 * GNUNET_SYSERR, invalid input,
 * GNUNET_YES: could convert to ip,
 * GNUNET_NO: valid input but could not convert to ip (hostname?)
 * @return the string
 */
struct sockaddr *
http_common_socket_from_address (const void *addr, size_t addrlen, int *res)
{
	const struct HttpAddress *ha;
	struct SplittedHTTPAddress * spa;
  struct sockaddr_storage *s;
  (*res) = GNUNET_SYSERR;
  char * to_conv;

  ha = (const struct HttpAddress *) addr;
  if (NULL == addr)
	{
		GNUNET_break (0);
		return NULL;
	}
  if (0 >= addrlen)
	{
		GNUNET_break (0);
		return NULL;
	}
  if (addrlen < sizeof (struct HttpAddress))
	{
		GNUNET_break (0);
		return NULL;
	}
  if (addrlen < sizeof (struct HttpAddress) + ntohl (ha->urlen))
	{
		/* This is a legacy addresses */
		return NULL;
	}
  if (((char *) addr)[addrlen-1] != '\0')
	{
		GNUNET_break (0);
		return NULL;
	}
  spa = http_split_address ((const char *) &ha[1]);
  if (NULL == spa)
  {
      (*res) = GNUNET_SYSERR;
      return NULL;
  }

  s = GNUNET_malloc (sizeof (struct sockaddr_storage));
  GNUNET_asprintf (&to_conv, "%s:%u", spa->host, spa->port);
  if (GNUNET_SYSERR == GNUNET_STRINGS_to_address_ip (to_conv, strlen(to_conv), s))
  {
    /* could be a hostname */
  	GNUNET_free (s);
    (*res) = GNUNET_NO;
    s = NULL;
  }
  else if ((AF_INET != s->ss_family) && (AF_INET6 != s->ss_family))
  {

		GNUNET_free (s);
		(*res) = GNUNET_SYSERR;
		s = NULL;
  }
  else
  {
  		(*res) = GNUNET_YES;
  }
	http_clean_splitted (spa);
  GNUNET_free (to_conv);
  return (struct sockaddr *) s;
}

/**
 * Get the length of an address
 *
 * @param addr address
 * @return the size
 */
size_t
http_common_address_get_size (const struct HttpAddress * addr)
{
 return sizeof (struct HttpAddress) + ntohl(addr->urlen);
}

/**
 * Compare addr1 to addr2
 *
 * @param addr1 address1
 * @param addrlen1 address 1 length
 * @param addr2 address2
 * @param addrlen2 address 2 length
 * @return GNUNET_YES if equal, GNUNET_NO if not, GNUNET_SYSERR on error
 */
size_t
http_common_cmp_addresses (const void *addr1, size_t addrlen1, const void *addr2, size_t addrlen2)
{
	const struct HttpAddress *ha1;
	const struct HttpAddress *ha2;
  const char *a1 = (const char *) addr1;
  const char *a2 = (const char *) addr2;
  ha1 = (const struct HttpAddress *) a1;
  ha2 = (const struct HttpAddress *) a2;

  if (NULL == a1)
      return GNUNET_SYSERR;
  if (0 >= addrlen1)
    return GNUNET_SYSERR;
  if (a1[addrlen1-1] != '\0')
    return GNUNET_SYSERR;

  if (NULL == a2)
      return GNUNET_SYSERR;
  if (0 >= addrlen2)
    return GNUNET_SYSERR;
  if (a2[addrlen2-1] != '\0')
    return GNUNET_SYSERR;

  if (addrlen1 != addrlen2)
    return GNUNET_NO;
  if (ha1->urlen != ha2->urlen)
    return GNUNET_NO;

  if (0 == strcmp ((const char *) &ha1[1],(const char *) &ha2[1]))
    return GNUNET_YES;
  return GNUNET_NO;
}



/* end of plugin_transport_http_common.c */