/*
 * Copyright (c) 2016 Cisco and/or its affiliates.
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at:
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#include <vnet/lisp-cp/lisp_types.h>

typedef u16 (*size_to_write_fct)(void *);
typedef void * (*cast_fct)(gid_address_t *);
typedef u16 (*write_fct)(u8 *, void *);
typedef u8 (*addr_len_fct)(void *);
typedef void (*copy_fct)(void *, void *);

size_to_write_fct size_to_write_fcts[GID_ADDR_TYPES] =
  { ip_prefix_size_to_write };
write_fct write_fcts[GID_ADDR_TYPES] =
  { ip_prefix_write };
cast_fct cast_fcts[GID_ADDR_TYPES] =
  { ip_prefix_cast };
addr_len_fct addr_len_fcts[GID_ADDR_TYPES] =
  { ip_prefix_length };
copy_fct copy_fcts[GID_ADDR_TYPES] =
  { ip_prefix_copy };

u8 *
format_ip_address (u8 * s, va_list * args)
{
  ip_address_t * a = va_arg (*args, ip_address_t *);
  u8 ver = ip_addr_version(a);
  if (ver == IP4)
    {
      return format (s, "%U", format_ip4_address, &ip_addr_v4(a));
    }
  else if (ver == IP6)
    {
      return format (s, "%U", format_ip6_address, &ip_addr_v6(a));
    }
  else
    {
      clib_warning ("Can't format IP version %d!", ver);
      return 0;
    }
}

uword
unformat_ip_address (unformat_input_t * input, va_list * args)
{
  ip_address_t * a = va_arg(*args, ip_address_t *);
  if (unformat(input, "%U", unformat_ip4_address, &ip_addr_v4(a)))
    ip_addr_version(a) = IP4;
  else if (unformat_user (input, unformat_ip6_address, &ip_addr_v6(a)))
    ip_addr_version(a) = IP6;
  else
    return 0;
  return 1;
}

u8 *
format_ip_prefix (u8 * s, va_list * args)
{
  ip_prefix_t * a = va_arg (*args, ip_prefix_t *);
  return format (s, "%U/%d", format_ip_address, &ip_prefix_addr(a), ip_prefix_len(a));
}

uword
unformat_ip_prefix (unformat_input_t * input, va_list * args)
{
  ip_prefix_t * a = va_arg(*args, ip_prefix_t *);
  return unformat (input, "%U/%d", unformat_ip_address, &ip_prefix_addr(a),
                   &ip_prefix_len(a));
}

u8 *
format_gid_address (u8 * s, va_list * args)
{
  gid_address_t * a = va_arg(*args, gid_address_t *);
  u8 type = gid_address_type(a);
  switch (type)
    {
    case IP_PREFIX:
      return format (s, "%U", format_ip_prefix, &gid_address_ippref(a));
    default:
      clib_warning("Can't format gid type %d", type);
      return 0;
    }
}

uword
unformat_gid_address (unformat_input_t * input, va_list * args)
{
  gid_address_t * a = va_arg(*args, gid_address_t *);
  if (unformat (input, "%U", unformat_ip_prefix, &gid_address_ippref(a)))
    gid_address_type(a) = IP_PREFIX;
  else
    return 0;
  return 1;
}

u16
ip_address_size (ip_address_t * a)
{
  switch (ip_addr_version (a))
  {
    case IP4:
      return sizeof(ip4_address_t);
      break;
    case IP6:
      return sizeof(ip6_address_t);
      break;
  }
  return 0;
}

u16
ip_version_to_size (u8 ver)
{
  switch (ver)
  {
    case IP4:
      return sizeof(ip4_address_t);
      break;
    case IP6:
      return sizeof(ip6_address_t);
      break;
  }
  return 0;
}

u8
ip_version_to_max_plen (u8 ver)
{
  switch (ver)
  {
    case IP4:
      return 32;
      break;
    case IP6:
      return 128;
      break;
  }
  return 0;
}

always_inline lisp_afi_e
ip_version_to_iana_afi (u16 version)
{
  switch (version)
    {
    case IP4:
      return LISP_AFI_IP;
    case IP6:
      return LISP_AFI_IP6;
    default:
      return 0;
    }
  return 0;
}

always_inline u8
ip_iana_afi_to_version (lisp_afi_e afi)
{
  switch (afi)
    {
    case LISP_AFI_IP:
      return IP4;
    case LISP_AFI_IP6:
      return IP6;
    default:
      return 0;
    }
  return 0;
}

u16
ip_address_size_to_write (ip_address_t * a)
{
  return ip_address_size (a) + sizeof (u16);
}

u16
ip_address_iana_afi(ip_address_t *a)
{
    return ip_version_to_iana_afi(ip_addr_version(a));
}

u8
ip_address_max_len (u8 version)
{
  return version == IP4 ? 32 : 128;
}

u16
ip4_address_size_to_put ()
{
  // return sizeof(u16) + sizeof (ip4_address_t);
  return 6;
}

u16
ip6_address_size_to_put ()
{
  //return sizeof(u16) + sizeof (ip6_address_t);
  return 18;
}

u32
ip4_address_put (u8 * b, ip4_address_t * a)
{
  *(u16 *)b = clib_host_to_net_u16(ip_version_to_iana_afi(IP4));
  u8 *p = b + sizeof (u16);
  clib_memcpy (p, a, sizeof(*a));
  return ip4_address_size_to_put();
}

u32
ip6_address_put (u8 * b, ip6_address_t * a)
{
  *(u16 *)b = clib_host_to_net_u16(ip_version_to_iana_afi(IP6));
  u8 *p = b + sizeof (u16);
  clib_memcpy (p, a, sizeof(*a));
  return ip6_address_size_to_put();
}

u32
ip_address_put (u8 * b, ip_address_t * a)
{
  u32 len = ip_address_size (a);
  *(u16 *) b = clib_host_to_net_u16(ip_address_iana_afi (a));
  u8 * p = b + sizeof (u16);
  clib_memcpy (p, &ip_addr_addr (a), len);
  return (len + sizeof (u16));
}

u32
ip_address_parse(void * offset, u16 iana_afi, ip_address_t *dst)
{
  ip_addr_version(dst) = ip_iana_afi_to_version (iana_afi);
  u8 size = ip_version_to_size (ip_addr_version(dst));
  clib_memcpy (&ip_addr_addr(dst), offset + sizeof(u16), size);
  return(sizeof(u16) + size);
}

int
ip_address_cmp (ip_address_t * ip1, ip_address_t * ip2)
{
  int res = 0;
  if (ip_addr_version (ip1) != ip_addr_version(ip2))
    return -1;
  res = memcmp (&ip_addr_addr(ip1), &ip_addr_addr(ip2), ip_address_size (ip1));

  if (res < 0)
    res = 2;
  else if (res > 0)
    res = 1;

  return res;
}

void *
ip_prefix_cast (gid_address_t * a)
{
  return &gid_address_ippref(a);
}

u16
ip_prefix_size_to_write (void * pref)
{
  ip_prefix_t *a = (ip_prefix_t *) pref;
  return ip_address_size_to_write (&ip_prefix_addr (a));
}

u16
ip_prefix_write (u8 * p, void * pref)
{
  ip_prefix_t *a = (ip_prefix_t *) pref;
  switch (ip_prefix_version (a))
  {
    case IP4:
      return ip4_address_put (p, &ip_prefix_v4 (a));
      break;
    case IP6:
      return ip6_address_put (p, &ip_prefix_v6 (a));
      break;
  }
  return 0;
}

u8
ip_prefix_length (void *a)
{
  return ip_prefix_len((ip_prefix_t *) a);
}

void
ip_prefix_copy (void * dst , void * src)
{
  clib_memcpy (dst, src, sizeof (ip_prefix_t));
}

int
ip_prefix_cmp(ip_prefix_t * p1, ip_prefix_t * p2)
{
  int cmp = 0;
  cmp = ip_address_cmp (&ip_prefix_addr(p1), &ip_prefix_addr(p2));
  if (cmp == 0)
  {
    if (ip_prefix_len(p1) < ip_prefix_len(p2))
    {
      cmp = 1;
    }
    else
    {
      if (ip_prefix_len(p1) > ip_prefix_len(p2))
        cmp = 2;
    }
  }
  return cmp;
}

u8
gid_address_len (gid_address_t *a)
{
  gid_address_type_t type = gid_address_type (a);
  return (*addr_len_fcts[type])((*cast_fcts[type])(a));
}

u16
gid_address_put (u8 * b, gid_address_t * gid)
{
  gid_address_type_t type = gid_address_type (gid);
  return (*write_fcts[type])(b, (*cast_fcts[type])(gid));
}

u16
gid_address_size_to_put (gid_address_t * gid)
{
  gid_address_type_t type = gid_address_type (gid);
  return (*size_to_write_fcts[type])((*cast_fcts[type])(gid));
}

void *
gid_address_cast (gid_address_t * gid, gid_address_type_t type)
{
  return (*cast_fcts[type])(gid);
}

void
gid_address_copy(gid_address_t * dst, gid_address_t * src)
{
  gid_address_type_t type = gid_address_type(src);
  (*copy_fcts[type])((*cast_fcts[type])(dst), (*cast_fcts[type])(src));
  gid_address_type(dst) = type;
}

u32
gid_address_parse (u8 * offset, gid_address_t *a)
{
  lisp_afi_e afi;
  int len = 0;

  if (!a)
    return 0;

  afi = clib_net_to_host_u16 (*((u16 *) offset));

  switch (afi)
    {
    case LISP_AFI_NO_ADDR:
      len = sizeof(u16);
      gid_address_type(a) = NO_ADDRESS;
      break;
    case LISP_AFI_IP:
      len = ip_address_parse (offset, afi, &gid_address_ip(a));
      gid_address_type(a) = IP_PREFIX;
      /* this should be modified outside if needed*/
      gid_address_ippref_len(a) = 32;
      break;
    case LISP_AFI_IP6:
      len = ip_address_parse (offset, afi, &gid_address_ip(a));
      gid_address_type(a) = IP_PREFIX;
      /* this should be modified outside if needed*/
      gid_address_ippref_len(a) = 128;
      break;
    case LISP_AFI_LCAF:
    default:
      clib_warning("LISP AFI %d not supported!", afi);
      return ~0;
    }
  return len;
}

/* Compare two gid_address_t.
 * Returns:
 *        -1: If they are from different afi
 *             0: Both address are the same
 *             1: Addr1 is bigger than addr2
 *             2: Addr2 is bigger than addr1
 */
int
gid_address_cmp (gid_address_t * a1, gid_address_t * a2)
{
  int cmp = -1;
  if (!a1 || !a2)
    return -1;
  if (gid_address_type(a1) != gid_address_type(a2))
    return -1;

  switch (gid_address_type(a1))
    {
    case NO_ADDRESS:
      if (a1 == a2)
        cmp = 0;
      else
        cmp = 2;
      break;
    case IP_PREFIX:
      cmp = ip_prefix_cmp (&gid_address_ippref(a1), &gid_address_ippref(a2));
      break;
    default:
      break;
    }

  return cmp;
}


u32
locator_parse (void * b, locator_t * loc)
{
  locator_hdr_t * h;
  u8 status = 1; /* locator up */
  int len;

  h = b;
  if (!LOC_REACHABLE(h) && LOC_LOCAL(h))
    status = 0;

  len = gid_address_parse (LOC_ADDR(h), &loc->address);
  if (len == ~0)
    return len;

  loc->state = status;
  loc->local = 0;
  loc->priority = LOC_PRIORITY(h);
  loc->weight = LOC_WEIGHT(h);
  loc->mpriority = LOC_MPRIORITY(h);
  loc->mweight = LOC_MWEIGHT(h);

  return sizeof(locator_hdr_t) + len;
}

void
locator_copy (locator_t * dst, locator_t * src)
{
  /* TODO if gid become more complex, this will need to be changed! */
  clib_memcpy (dst, src, sizeof(*dst));
}

u32
locator_cmp (locator_t * l1, locator_t * l2)
{
  u32 ret = 0;
  if ((ret = gid_address_cmp (&l1->address, &l2->address)) != 0)
    return 1;

  if (l1->priority != l2->priority)
    return 1;
  if (l1->weight != l2->weight)
    return 1;
  if (l1->mpriority != l2->mpriority)
    return 1;
  if (l1->mweight != l2->mweight)
    return 1;
  return 0;
}