/*
     This file is part of GNUnet.
     (C) 2011 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 ats/gnunet-service-ats_addresses.c
 * @brief ats service address management
 * @author Matthias Wachs
 * @author Christian Grothoff
 */
#include "platform.h"
#include "gnunet-service-ats_addresses.h"
#include "gnunet-service-ats_performance.h"
#include "gnunet-service-ats_scheduling.h"
#include "gnunet-service-ats_reservations.h"

struct ATS_Address
{
  struct GNUNET_PeerIdentity peer;

  size_t addr_len;

  uint32_t session_id;

  uint32_t ats_count;

  const void * addr;

  char * plugin;

  struct GNUNET_ATS_Information * ats;

  struct GNUNET_BANDWIDTH_Value32NBO atsp_utilization_in;

  struct GNUNET_BANDWIDTH_Value32NBO atsp_utilization_out;

  struct GNUNET_TIME_Relative atsp_latency;

  uint32_t atsp_distance;

  uint32_t atsp_cost_wan;

  uint32_t atsp_cost_lan;

  uint32_t atsp_cost_wlan;

  struct GNUNET_BANDWIDTH_Value32NBO assigned_bw_in;

  struct GNUNET_BANDWIDTH_Value32NBO assigned_bw_out;

  struct GNUNET_BANDWIDTH_Value32NBO bw_in;

  struct GNUNET_BANDWIDTH_Value32NBO bw_out;

};


static struct GNUNET_CONTAINER_MultiHashMap * addresses;

static unsigned long long total_quota_in;

static unsigned long long total_quota_out;

static unsigned int active_addr_count;


struct CompareAddressContext
{
  struct ATS_Address * search;
  struct ATS_Address * result;
};


static void
destroy_address (struct ATS_Address *addr)
{
  GNUNET_assert (GNUNET_YES == 
		 GNUNET_CONTAINER_multihashmap_remove(addresses, 
						      &addr->peer.hashPubKey, 
						      addr));
  if (ntohl (addr->bw_in.value__) > 0)
  {
    active_addr_count--;
    // FIXME: update address assignment for other peers...
  }
  GNUNET_free_non_null (addr->ats);
  GNUNET_free (addr->plugin);
  GNUNET_free (addr);
}


static int 
compare_address_it (void *cls,
		    const GNUNET_HashCode * key,
		    void *value)
{
  struct CompareAddressContext * cac = cls;
  struct ATS_Address * aa = (struct ATS_Address *) value;

  /* compare sessions */
  if (aa->session_id != cac->search->session_id)
    return GNUNET_YES;

  if (aa->addr_len != cac->search->addr_len)
  {
    return GNUNET_YES;
  }

  if (0 == strcmp(aa->plugin, cac->search->plugin))
  {
    return GNUNET_YES;
  }

  if (0 == memcmp (aa->addr, cac->search->addr, aa->addr_len))
  {
    cac->result = aa;
    return GNUNET_NO;
  }
  return GNUNET_YES;
}


struct ATS_Address *
find_address (const struct GNUNET_PeerIdentity *peer,
              struct ATS_Address * addr)
{
  struct CompareAddressContext cac;
  cac.result = NULL;
  cac.search = addr;

  GNUNET_CONTAINER_multihashmap_get_multiple(addresses,
         &peer->hashPubKey,
         compare_address_it,
         &cac);

  return cac.result;
}


void
GAS_addresses_update (const struct GNUNET_PeerIdentity *peer,
		      const char *plugin_name,
		      const void *plugin_addr, size_t plugin_addr_len,
		      uint32_t session_id,
		      const struct GNUNET_ATS_Information *atsi,
		      uint32_t atsi_count)
{
  struct ATS_Address * aa;
  struct ATS_Address * old;

  aa = GNUNET_malloc (sizeof (struct ATS_Address) + plugin_addr_len);
  aa->ats = GNUNET_malloc(atsi_count * sizeof (struct GNUNET_ATS_Information));
  aa->peer = *peer;
  aa->addr_len = plugin_addr_len;
  aa->ats_count = atsi_count;
  memcpy (aa->ats, atsi, atsi_count * sizeof (struct GNUNET_ATS_Information));
  aa->addr = &aa[1];
  memcpy (&aa[1], plugin_addr, plugin_addr_len);
  aa->plugin = GNUNET_strdup (plugin_name);
  aa->session_id = session_id;
  old = find_address (peer, aa);
  if (old == NULL)
  {
    GNUNET_assert (GNUNET_OK ==
                   GNUNET_CONTAINER_multihashmap_put (addresses,
						      &peer->hashPubKey,
						      aa,
						      GNUNET_CONTAINER_MULTIHASHMAPOPTION_MULTIPLE));
    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
		"Added new address for peer `%s' %X\n",
		GNUNET_i2s (peer), aa);
    return;
  }
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
	      "Updated existing address for peer `%s' %X \n",
	      GNUNET_i2s (peer), old);
  GNUNET_free_non_null (old->ats);
  old->ats = NULL;
  old->ats_count = 0;
  old->ats = aa->ats;
  old->ats_count = aa->ats_count;
  GNUNET_free (aa->plugin);
  GNUNET_free (aa);
}


void
GAS_addresses_destroy (const struct GNUNET_PeerIdentity *peer,
		       const char *plugin_name,
		       const void *plugin_addr, size_t plugin_addr_len,
		       uint32_t session_id)
{

  struct ATS_Address aa;
  struct ATS_Address *res;

  aa.peer = *peer;
  aa.addr_len = plugin_addr_len;
  aa.addr = plugin_addr;
  aa.plugin = (char*) plugin_name;
  aa.session_id = session_id;

  res = find_address (peer, &aa);
  if (res == NULL)
  {
    /* we don't even know this one, can this happen? */
    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
		"Asked to delete unknown address for peer `%s'\n",
		GNUNET_i2s (peer));
    return; 
  }
  GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
	      "Deleting address for peer `%s': `%s'\n",
	      GNUNET_i2s (peer), plugin_name);
  destroy_address (res);
}


void
GAS_addresses_request_address (const struct GNUNET_PeerIdentity *peer)
{
  struct ATS_Address * aa;

  aa = GNUNET_CONTAINER_multihashmap_get (addresses, &peer->hashPubKey);
  if (aa == NULL)
  {
    GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
		"Cannot suggest address for peer `%s'\n",
		GNUNET_i2s (peer));
    return; 
  }
  /* FIXME: ensure that we don't do this multiple times per peer! */
  if (ntohl (aa->bw_in.value__) == 0)
  {
    active_addr_count++;
    aa->bw_in.value__ = htonl (total_quota_in / active_addr_count);
    aa->bw_out.value__ = htonl (total_quota_out / active_addr_count);
    /* FIXME: update bw assignments for other addresses... */
  }
  GAS_reservations_set_bandwidth (peer,
				  aa->bw_in);
  GAS_scheduling_transmit_address_suggestion (peer, aa->plugin, 
					      aa->addr, aa->addr_len, 
					      aa->session_id, 
					      aa->ats, aa->ats_count, 
					      aa->bw_out, aa->bw_in);
  GAS_performance_notify_clients (peer, aa->plugin, 
				  aa->addr, aa->addr_len, 
				  aa->ats, aa->ats_count, 
				  aa->bw_out, aa->bw_in);
}


// FIXME: this function should likely end up in the LP-subsystem and
// not with 'addresses' in the future...
void
GAS_addresses_change_preference (const struct GNUNET_PeerIdentity *peer,
				 enum GNUNET_ATS_PreferenceKind kind,
				 float score)
{
  // do nothing for now...
}


/**
 * Initialize address subsystem.
 *
 * @param cfg configuration to use
 */
void
GAS_addresses_init (const struct GNUNET_CONFIGURATION_Handle *cfg)
{
  GNUNET_assert (GNUNET_OK ==
		 GNUNET_CONFIGURATION_get_value_number (cfg,
							"core",
							"TOTAL_QUOTA_IN",
							&total_quota_in));
  GNUNET_assert (GNUNET_OK ==
		 GNUNET_CONFIGURATION_get_value_number (cfg,
							"core",
							"TOTAL_QUOTA_OUT",
							&total_quota_out));
  addresses = GNUNET_CONTAINER_multihashmap_create(128);
}


/**
 * Free memory of address.
 *
 * @param cls NULL
 * @param key peer identity (unused)
 * @param value the 'struct ATS_Address' to free
 * @return GNUNET_OK (continue to iterate)
 */
static int 
free_address_it (void *cls,
		 const GNUNET_HashCode * key,
		 void *value)
{
  struct ATS_Address * aa = value;

  destroy_address (aa);
  return GNUNET_OK;
}


void
GAS_addresses_destroy_all ()
{
  if (addresses != NULL)
    GNUNET_CONTAINER_multihashmap_iterate(addresses, 
					  &free_address_it, NULL);
}


/**
 * Shutdown address subsystem.
 */
void
GAS_addresses_done ()
{
  GAS_addresses_destroy_all ();
  GNUNET_CONTAINER_multihashmap_destroy (addresses);
  addresses = NULL;
}


/* end of gnunet-service-ats_addresses.c */