/*
  PIM for Quagga
  Copyright (C) 2008  Everton da Silva Marques

  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; either version 2 of the License, or
  (at your option) any later version.

  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; see the file COPYING; if not, write to the
  Free Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston,
  MA 02110-1301 USA
  
  $QuaggaId: $Format:%an, %ai, %h$ $
*/

#ifndef PIM_IFCHANNEL_H
#define PIM_IFCHANNEL_H

#include <zebra.h>

#include "if.h"

#include "pim_upstream.h"

enum pim_ifmembership {
  PIM_IFMEMBERSHIP_NOINFO,
  PIM_IFMEMBERSHIP_INCLUDE
};

enum pim_ifjoin_state {
  PIM_IFJOIN_NOINFO,
  PIM_IFJOIN_JOIN,
  PIM_IFJOIN_PRUNE_PENDING
};

enum pim_ifassert_state {
  PIM_IFASSERT_NOINFO,
  PIM_IFASSERT_I_AM_WINNER,
  PIM_IFASSERT_I_AM_LOSER
};

struct pim_assert_metric {
  uint32_t       rpt_bit_flag;
  uint32_t       metric_preference;
  uint32_t       route_metric;
  struct in_addr ip_address; /* neighbor router that sourced the Assert message */
};

/*
  Flag to detect change in CouldAssert(S,G,I)
*/
#define PIM_IF_FLAG_MASK_COULD_ASSERT (1 << 0)
#define PIM_IF_FLAG_TEST_COULD_ASSERT(flags) ((flags) & PIM_IF_FLAG_MASK_COULD_ASSERT)
#define PIM_IF_FLAG_SET_COULD_ASSERT(flags) ((flags) |= PIM_IF_FLAG_MASK_COULD_ASSERT)
#define PIM_IF_FLAG_UNSET_COULD_ASSERT(flags) ((flags) &= ~PIM_IF_FLAG_MASK_COULD_ASSERT)
/*
  Flag to detect change in AssertTrackingDesired(S,G,I)
*/
#define PIM_IF_FLAG_MASK_ASSERT_TRACKING_DESIRED (1 << 1)
#define PIM_IF_FLAG_TEST_ASSERT_TRACKING_DESIRED(flags) ((flags) & PIM_IF_FLAG_MASK_ASSERT_TRACKING_DESIRED)
#define PIM_IF_FLAG_SET_ASSERT_TRACKING_DESIRED(flags) ((flags) |= PIM_IF_FLAG_MASK_ASSERT_TRACKING_DESIRED)
#define PIM_IF_FLAG_UNSET_ASSERT_TRACKING_DESIRED(flags) ((flags) &= ~PIM_IF_FLAG_MASK_ASSERT_TRACKING_DESIRED)

/*
  Per-interface (S,G) state
*/
struct pim_ifchannel {
  struct in_addr            source_addr; /* (S,G) source key */
  struct in_addr            group_addr;  /* (S,G) group key */
  struct interface         *interface;   /* backpointer to interface */
  uint32_t                  flags;

  /* IGMPv3 determined interface has local members for (S,G) ? */
  enum pim_ifmembership     local_ifmembership;

  /* Per-interface (S,G) Join/Prune State (Section 4.1.4 of RFC4601) */
  enum pim_ifjoin_state     ifjoin_state;
  struct thread            *t_ifjoin_expiry_timer;
  struct thread            *t_ifjoin_prune_pending_timer;
  int64_t                   ifjoin_creation; /* Record uptime of ifjoin state */

  /* Per-interface (S,G) Assert State (Section 4.6.1 of RFC4601) */
  enum pim_ifassert_state   ifassert_state;
  struct thread            *t_ifassert_timer;
  struct in_addr            ifassert_winner;
  struct pim_assert_metric  ifassert_winner_metric;
  int64_t                   ifassert_creation; /* Record uptime of ifassert state */
  struct pim_assert_metric  ifassert_my_metric;

  /* Upstream (S,G) state */
  struct pim_upstream      *upstream;
};

void pim_ifchannel_free(struct pim_ifchannel *ch);
void pim_ifchannel_delete(struct pim_ifchannel *ch);
void pim_ifchannel_membership_clear(struct interface *ifp);
void pim_ifchannel_delete_on_noinfo(struct interface *ifp);
struct pim_ifchannel *pim_ifchannel_find(struct interface *ifp,
					 struct in_addr source_addr,
					 struct in_addr group_addr);
struct pim_ifchannel *pim_ifchannel_add(struct interface *ifp,
					struct in_addr source_addr,
					struct in_addr group_addr);
void pim_ifchannel_join_add(struct interface *ifp,
			    struct in_addr neigh_addr,
			    struct in_addr upstream,
			    struct in_addr source_addr,
			    struct in_addr group_addr,
			    uint8_t source_flags,
			    uint16_t holdtime);
void pim_ifchannel_prune(struct interface *ifp,
			 struct in_addr upstream,
			 struct in_addr source_addr,
			 struct in_addr group_addr,
			 uint8_t source_flags,
			 uint16_t holdtime);
void pim_ifchannel_local_membership_add(struct interface *ifp,
					struct in_addr source_addr,
					struct in_addr group_addr);
void pim_ifchannel_local_membership_del(struct interface *ifp,
					struct in_addr source_addr,
					struct in_addr group_addr);

void pim_ifchannel_ifjoin_switch(const char *caller,
				 struct pim_ifchannel *ch,
				 enum pim_ifjoin_state new_state);
const char *pim_ifchannel_ifjoin_name(enum pim_ifjoin_state ifjoin_state);
const char *pim_ifchannel_ifassert_name(enum pim_ifassert_state ifassert_state);

int pim_ifchannel_isin_oiflist(struct pim_ifchannel *ch);

void reset_ifassert_state(struct pim_ifchannel *ch);

void pim_ifchannel_update_could_assert(struct pim_ifchannel *ch);
void pim_ifchannel_update_my_assert_metric(struct pim_ifchannel *ch);
void pim_ifchannel_update_assert_tracking_desired(struct pim_ifchannel *ch);

#endif /* PIM_IFCHANNEL_H */