/*
 * 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
 */

#include <zebra.h>

#include "log.h"
#include "memory.h"
#include "if.h"
#include "prefix.h"
#include "vty.h"
#include "plist.h"
#include "hash.h"
#include "jhash.h"

#include "pimd.h"
#include "pim_cmd.h"
#include "pim_iface.h"
#include "pim_zebra.h"
#include "pim_str.h"
#include "pim_oil.h"
#include "pim_pim.h"
#include "pim_upstream.h"
#include "pim_rpf.h"
#include "pim_ssmpingd.h"
#include "pim_static.h"
#include "pim_rp.h"
#include "pim_ssm.h"
#include "pim_zlookup.h"
#include "pim_nht.h"

const char *const PIM_ALL_SYSTEMS      = MCAST_ALL_SYSTEMS;
const char *const PIM_ALL_ROUTERS      = MCAST_ALL_ROUTERS;
const char *const PIM_ALL_PIM_ROUTERS  = MCAST_ALL_PIM_ROUTERS;
const char *const PIM_ALL_IGMP_ROUTERS = MCAST_ALL_IGMP_ROUTERS;

struct thread_master     *master = NULL;
uint32_t                  qpim_debugs = 0;
int                       qpim_mroute_socket_fd = -1;
int64_t                   qpim_mroute_socket_creation = 0; /* timestamp of creation */
int                       qpim_t_periodic = PIM_DEFAULT_T_PERIODIC; /* Period between Join/Prune Messages */
struct pim_assert_metric  qpim_infinite_assert_metric;
long                      qpim_rpf_cache_refresh_delay_msec = 50;
struct thread            *qpim_rpf_cache_refresher = NULL;
int64_t                   qpim_rpf_cache_refresh_requests = 0;
int64_t                   qpim_rpf_cache_refresh_events = 0;
int64_t                   qpim_rpf_cache_refresh_last =  0;
struct in_addr            qpim_inaddr_any;
struct list              *qpim_ssmpingd_list = NULL;
struct in_addr            qpim_ssmpingd_group_addr;
int64_t                   qpim_scan_oil_events = 0;
int64_t                   qpim_scan_oil_last = 0;
int64_t                   qpim_mroute_add_events = 0;
int64_t                   qpim_mroute_add_last = 0;
int64_t                   qpim_mroute_del_events = 0;
int64_t                   qpim_mroute_del_last = 0;
struct list              *qpim_static_route_list = NULL;
unsigned int              qpim_keep_alive_time = PIM_KEEPALIVE_PERIOD;
signed int                qpim_rp_keep_alive_time = 0;
int64_t                   qpim_nexthop_lookups = 0;
int                       qpim_packet_process = PIM_DEFAULT_PACKET_PROCESS;
uint8_t                   qpim_ecmp_enable = 0;
uint8_t                   qpim_ecmp_rebalance_enable = 0;
struct pim_instance       *pimg = NULL;

int32_t qpim_register_suppress_time = PIM_REGISTER_SUPPRESSION_TIME_DEFAULT;
int32_t qpim_register_probe_time = PIM_REGISTER_PROBE_TIME_DEFAULT;

static struct pim_instance *pim_instance_init (vrf_id_t vrf_id, afi_t afi);
static void pim_instance_terminate (void);

static int
pim_vrf_new (struct vrf *vrf)
{
  zlog_debug ("VRF Created: %s(%d)", vrf->name, vrf->vrf_id);
  return 0;
}

static int
pim_vrf_delete (struct vrf *vrf)
{
  zlog_debug ("VRF Deletion: %s(%d)", vrf->name, vrf->vrf_id);
  return 0;
}

static int
pim_vrf_enable (struct vrf *vrf)
{

  if (!vrf) // unexpected
    return -1;

  if (vrf->vrf_id == VRF_DEFAULT)
    {
      pimg = pim_instance_init (VRF_DEFAULT, AFI_IP);
      if (pimg == NULL)
        {
          zlog_err ("%s %s: pim class init failure ", __FILE__,
                    __PRETTY_FUNCTION__);
          /*
           * We will crash and burn otherwise
           */
          exit(1);
      }

    pimg->send_v6_secondary = 1;

    }
  return 0;
}

static int
pim_vrf_disable (struct vrf *vrf)
{
  if (vrf->vrf_id == VRF_DEFAULT)
    return 0;

  if (vrf->vrf_id == VRF_DEFAULT)
    pim_instance_terminate ();

  /* Note: This is a callback, the VRF will be deleted by the caller. */
  return 0;
}

void
pim_vrf_init (void)
{
  vrf_add_hook (VRF_NEW_HOOK, pim_vrf_new);
  vrf_add_hook (VRF_ENABLE_HOOK, pim_vrf_enable);
  vrf_add_hook (VRF_DISABLE_HOOK, pim_vrf_disable);
  vrf_add_hook (VRF_DELETE_HOOK, pim_vrf_delete);

  vrf_init ();
}

static void
pim_vrf_terminate (void)
{
  vrf_add_hook (VRF_NEW_HOOK, NULL);
  vrf_add_hook (VRF_ENABLE_HOOK, NULL);
  vrf_add_hook (VRF_DISABLE_HOOK, NULL);
  vrf_add_hook (VRF_DELETE_HOOK, NULL);

  vrf_terminate ();
}

/* Key generate for pim->rpf_hash */
static unsigned int
pim_rpf_hash_key (void *arg)
{
  struct pim_nexthop_cache *r = (struct pim_nexthop_cache *) arg;

  return jhash_1word (r->rpf.rpf_addr.u.prefix4.s_addr, 0);
}

/* Compare pim->rpf_hash node data */
static int
pim_rpf_equal (const void *arg1, const void *arg2)
{
  const struct pim_nexthop_cache *r1 =
    (const struct pim_nexthop_cache *) arg1;
  const struct pim_nexthop_cache *r2 =
    (const struct pim_nexthop_cache *) arg2;

  return prefix_same (&r1->rpf.rpf_addr, &r2->rpf.rpf_addr);
}

/* Cleanup pim->rpf_hash each node data */
static void
pim_rp_list_hash_clean (void *data)
{
  struct pim_nexthop_cache *pnc;

  pnc = (struct pim_nexthop_cache *) data;
  if (pnc->rp_list->count)
    list_delete_all_node (pnc->rp_list);
  if (pnc->upstream_list->count)
    list_delete_all_node (pnc->upstream_list);
}

void
pim_prefix_list_update (struct prefix_list *plist)
{
    pim_rp_prefix_list_update (plist);
    pim_ssm_prefix_list_update (plist);
    pim_upstream_spt_prefix_list_update (plist);
}

static void
pim_instance_terminate (void)
{
  /* Traverse and cleanup rpf_hash */
  if (pimg->rpf_hash)
    {
      hash_clean (pimg->rpf_hash, (void *) pim_rp_list_hash_clean);
      hash_free (pimg->rpf_hash);
      pimg->rpf_hash = NULL;
    }

  if (pimg->ssm_info)
    {
      pim_ssm_terminate (pimg->ssm_info);
      pimg->ssm_info = NULL;
    }

  XFREE (MTYPE_PIM_PIM_INSTANCE, pimg);
}

static void pim_free()
{
  pim_ssmpingd_destroy();

  pim_oil_terminate ();

  pim_upstream_terminate ();

  if (qpim_static_route_list)
     list_free(qpim_static_route_list);

  pim_if_terminate ();
  pim_rp_free ();

  pim_route_map_terminate();

  zclient_lookup_free ();

  zprivs_terminate(&pimd_privs);
}

static struct pim_instance *
pim_instance_init (vrf_id_t vrf_id, afi_t afi)
{
  struct pim_instance *pim;

  pim = XCALLOC (MTYPE_PIM_PIM_INSTANCE, sizeof (struct pim_instance));
  if (!pim)
    return NULL;

  pim->vrf_id = vrf_id;
  pim->afi = afi;

  pim->spt.switchover = PIM_SPT_IMMEDIATE;
  pim->spt.plist = NULL;

  pim->rpf_hash = hash_create_size (256, pim_rpf_hash_key, pim_rpf_equal);

  if (PIM_DEBUG_ZEBRA)
    zlog_debug ("%s: NHT rpf hash init ", __PRETTY_FUNCTION__);

  pim->ssm_info = pim_ssm_init (vrf_id);
  if (!pim->ssm_info) {
    pim_instance_terminate ();
    return NULL;
  }

  return pim;
}

void pim_init()
{
  qpim_rp_keep_alive_time = PIM_RP_KEEPALIVE_PERIOD;

  pim_rp_init ();

  if (!inet_aton(PIM_ALL_PIM_ROUTERS, &qpim_all_pim_routers_addr)) {
    zlog_err("%s %s: could not solve %s to group address: errno=%d: %s",
	     __FILE__, __PRETTY_FUNCTION__,
	     PIM_ALL_PIM_ROUTERS, errno, safe_strerror(errno));
    zassert(0);
    return;
  }

  pim_oil_init ();

  pim_upstream_init ();

  qpim_static_route_list = list_new();
  if (!qpim_static_route_list) {
    zlog_err("%s %s: failure: static_route_list=list_new()",
        __FILE__, __PRETTY_FUNCTION__);
    return;
  }
  qpim_static_route_list->del = (void (*)(void *)) pim_static_route_free;

  pim_mroute_socket_enable();

  qpim_inaddr_any.s_addr = PIM_NET_INADDR_ANY;

  /*
    RFC 4601: 4.6.3.  Assert Metrics

    assert_metric
    infinite_assert_metric() {
    return {1,infinity,infinity,0}
    }
  */
  qpim_infinite_assert_metric.rpt_bit_flag      = 1;
  qpim_infinite_assert_metric.metric_preference = PIM_ASSERT_METRIC_PREFERENCE_MAX;
  qpim_infinite_assert_metric.route_metric      = PIM_ASSERT_ROUTE_METRIC_MAX;
  qpim_infinite_assert_metric.ip_address        = qpim_inaddr_any;

  pim_if_init();
  pim_cmd_init();
  pim_ssmpingd_init();
}

void pim_terminate()
{
  pim_free();

  /* reverse prefix_list_init */
  prefix_list_add_hook (NULL);
  prefix_list_delete_hook (NULL);
  prefix_list_reset ();

  pim_vrf_terminate ();
}