/*
 * 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/feature/feature.h>

vnet_feature_main_t feature_main;

static clib_error_t *
vnet_feature_init (vlib_main_t * vm)
{
  vnet_feature_main_t *fm = &feature_main;
  vnet_feature_registration_t *freg;
  vnet_feature_arc_registration_t *areg;
  u32 arc_index = 0;

  fm->arc_index_by_name = hash_create_string (0, sizeof (uword));
  areg = fm->next_arc;

  /* process feature arc registrations */
  while (areg)
    {
      char *s;
      int i = 0;
      areg->feature_arc_index = arc_index;
      if (areg->arc_index_ptr)
	*areg->arc_index_ptr = arc_index;
      hash_set_mem (fm->arc_index_by_name, areg->arc_name,
		    pointer_to_uword (areg));

      /* process start nodes */
      while ((s = areg->start_nodes[i]))
	{
	  i++;
	}
      areg->n_start_nodes = i;

      /* next */
      areg = areg->next;
      arc_index++;
    }

  vec_validate (fm->next_feature_by_arc, arc_index - 1);
  vec_validate (fm->feature_nodes, arc_index - 1);
  vec_validate (fm->feature_config_mains, arc_index - 1);
  vec_validate (fm->next_feature_by_name, arc_index - 1);
  vec_validate (fm->sw_if_index_has_features, arc_index - 1);
  vec_validate (fm->feature_count_by_sw_if_index, arc_index - 1);

  freg = fm->next_feature;
  while (freg)
    {
      vnet_feature_registration_t *next;
      uword *p = hash_get_mem (fm->arc_index_by_name, freg->arc_name);
      if (p == 0)
	return clib_error_return (0, "Unknown feature arc '%s'",
				  freg->arc_name);

      areg = uword_to_pointer (p[0], vnet_feature_arc_registration_t *);
      arc_index = areg->feature_arc_index;

      next = freg->next;
      freg->next = fm->next_feature_by_arc[arc_index];
      fm->next_feature_by_arc[arc_index] = freg;

      /* next */
      freg = next;
    }

  areg = fm->next_arc;
  while (areg)
    {
      clib_error_t *error;
      vnet_feature_config_main_t *cm;
      vnet_config_main_t *vcm;

      arc_index = areg->feature_arc_index;
      cm = &fm->feature_config_mains[arc_index];
      vcm = &cm->config_main;
      if ((error = vnet_feature_arc_init (vm, vcm,
					  areg->start_nodes,
					  areg->n_start_nodes,
					  fm->next_feature_by_arc[arc_index],
					  &fm->feature_nodes[arc_index])))
	{
	  return error;
	}

      fm->next_feature_by_name[arc_index] =
	hash_create_string (0, sizeof (uword));
      freg = fm->next_feature_by_arc[arc_index];

      while (freg)
	{
	  hash_set_mem (fm->next_feature_by_name[arc_index],
			freg->node_name, pointer_to_uword (freg));
	  freg = freg->next;
	}

      cm->end_feature_index =
	vnet_get_feature_index (arc_index, areg->end_node);

      /* next */
      areg = areg->next;
      arc_index++;
    }

  return 0;
}

VLIB_INIT_FUNCTION (vnet_feature_init);

u8
vnet_get_feature_arc_index (const char *s)
{
  vnet_feature_main_t *fm = &feature_main;
  vnet_feature_arc_registration_t *reg;
  uword *p;

  p = hash_get_mem (fm->arc_index_by_name, s);
  if (p == 0)
    return ~0;

  reg = uword_to_pointer (p[0], vnet_feature_arc_registration_t *);
  return reg->feature_arc_index;
}

vnet_feature_registration_t *
vnet_get_feature_reg (const char *arc_name, const char *node_name)
{
  u8 arc_index;

  arc_index = vnet_get_feature_arc_index (arc_name);
  if (arc_index == (u8) ~ 0)
    return 0;

  vnet_feature_main_t *fm = &feature_main;
  vnet_feature_registration_t *reg;
  uword *p;

  p = hash_get_mem (fm->next_feature_by_name[arc_index], node_name);
  if (p == 0)
    return 0;

  reg = uword_to_pointer (p[0], vnet_feature_registration_t *);
  return reg;
}

u32
vnet_get_feature_index (u8 arc, const char *s)
{
  vnet_feature_main_t *fm = &feature_main;
  vnet_feature_registration_t *reg;
  uword *p;

  if (s == 0)
    return ~0;

  p = hash_get_mem (fm->next_feature_by_name[arc], s);
  if (p == 0)
    return ~0;

  reg = uword_to_pointer (p[0], vnet_feature_registration_t *);
  return reg->feature_index;
}

int
vnet_feature_enable_disable_with_index (u8 arc_index, u32 feature_index,
					u32 sw_if_index, int enable_disable,
					void *feature_config,
					u32 n_feature_config_bytes)
{
  vnet_feature_main_t *fm = &feature_main;
  vnet_feature_config_main_t *cm;
  i16 feature_count;
  int is_first_or_last;
  u32 ci;

  if (arc_index == (u8) ~ 0)
    return VNET_API_ERROR_INVALID_VALUE;

  if (feature_index == ~0)
    return VNET_API_ERROR_INVALID_VALUE_2;

  cm = &fm->feature_config_mains[arc_index];
  vec_validate_init_empty (cm->config_index_by_sw_if_index, sw_if_index, ~0);
  ci = cm->config_index_by_sw_if_index[sw_if_index];

  vec_validate (fm->feature_count_by_sw_if_index[arc_index], sw_if_index);
  feature_count = fm->feature_count_by_sw_if_index[arc_index][sw_if_index];

  if (!enable_disable && feature_count < 1)
    return 0;

  ci = (enable_disable
	? vnet_config_add_feature
	: vnet_config_del_feature)
    (vlib_get_main (), &cm->config_main, ci, feature_index, feature_config,
     n_feature_config_bytes);
  cm->config_index_by_sw_if_index[sw_if_index] = ci;

  /* update feature count */
  enable_disable = (enable_disable > 0);
  feature_count += enable_disable ? 1 : -1;
  is_first_or_last = (feature_count == enable_disable);
  ASSERT (feature_count >= 0);

  if (is_first_or_last && cm->end_feature_index != ~0)
    {
      /*register end node */
      ci = (enable_disable
	    ? vnet_config_add_feature
	    : vnet_config_del_feature)
	(vlib_get_main (), &cm->config_main, ci, cm->end_feature_index, 0, 0);
      cm->config_index_by_sw_if_index[sw_if_index] = ci;
    }

  fm->sw_if_index_has_features[arc_index] =
    clib_bitmap_set (fm->sw_if_index_has_features[arc_index], sw_if_index,
		     (feature_count > 0));

  fm->feature_count_by_sw_if_index[arc_index][sw_if_index] = feature_count;
  return 0;
}

int
vnet_feature_enable_disable (const char *arc_name, const char *node_name,
			     u32 sw_if_index, int enable_disable,
			     void *feature_config, u32 n_feature_config_bytes)
{
  u32 feature_index;
  u8 arc_index;

  arc_index = vnet_get_feature_arc_index (arc_name);

  if (arc_index == (u8) ~ 0)
    return VNET_API_ERROR_INVALID_VALUE;

  feature_index = vnet_get_feature_index (arc_index, node_name);

  return vnet_feature_enable_disable_with_index (arc_index, feature_index,
						 sw_if_index, enable_disable,
						 feature_config,
						 n_feature_config_bytes);
}


/** Display the set of available driver features.
    Useful for verifying that expected features are present
*/

static clib_error_t *
show_features_command_fn (vlib_main_t * vm,
			  unformat_input_t * input, vlib_cli_command_t * cmd)
{
  vnet_feature_main_t *fm = &feature_main;
  vnet_feature_arc_registration_t *areg;
  vnet_feature_registration_t *freg;

  vlib_cli_output (vm, "Available feature paths");

  areg = fm->next_arc;
  while (areg)
    {
      vlib_cli_output (vm, "%s:", areg->arc_name);
      freg = fm->next_feature_by_arc[areg->feature_arc_index];
      while (freg)
	{
	  vlib_cli_output (vm, "  %s\n", freg->node_name);
	  freg = freg->next;
	}


      /* next */
      areg = areg->next;
    }

  return 0;
}

/*?
 * Display the set of available driver features
 *
 * @cliexpar
 * Example:
 * @cliexcmd{show ip features}
 * @cliexend
 * @endparblock
?*/
/* *INDENT-OFF* */
VLIB_CLI_COMMAND (show_features_command, static) = {
  .path = "show features",
  .short_help = "show features",
  .function = show_features_command_fn,
};
/* *INDENT-ON* */

/** Display the set of driver features configured on a specific interface
  * Called by "show interface" handler
 */

void
vnet_interface_features_show (vlib_main_t * vm, u32 sw_if_index)
{
  vnet_feature_main_t *fm = &feature_main;
  u32 node_index, current_config_index;
  u16 feature_arc;
  vnet_feature_config_main_t *cm = fm->feature_config_mains;
  vnet_feature_arc_registration_t *areg;
  vnet_config_main_t *vcm;
  vnet_config_t *cfg;
  u32 cfg_index;
  vnet_config_feature_t *feat;
  vlib_node_t *n;
  int i;

  vlib_cli_output (vm, "Driver feature paths configured on %U...",
		   format_vnet_sw_if_index_name,
		   vnet_get_main (), sw_if_index);

  areg = fm->next_arc;
  while (areg)
    {
      feature_arc = areg->feature_arc_index;
      vcm = &(cm[feature_arc].config_main);

      vlib_cli_output (vm, "\n%s:", areg->arc_name);
      areg = areg->next;

      if (NULL == cm[feature_arc].config_index_by_sw_if_index ||
	  vec_len (cm[feature_arc].config_index_by_sw_if_index) <=
	  sw_if_index)
	{
	  vlib_cli_output (vm, "  none configured");
	  continue;
	}

      current_config_index =
	vec_elt (cm[feature_arc].config_index_by_sw_if_index, sw_if_index);

      if (current_config_index == ~0)
	{
	  vlib_cli_output (vm, "  none configured");
	  continue;
	}

      ASSERT (current_config_index
	      < vec_len (vcm->config_pool_index_by_user_index));

      cfg_index = vcm->config_pool_index_by_user_index[current_config_index];
      cfg = pool_elt_at_index (vcm->config_pool, cfg_index);

      for (i = 0; i < vec_len (cfg->features); i++)
	{
	  feat = cfg->features + i;
	  node_index = feat->node_index;
	  n = vlib_get_node (vm, node_index);
	  vlib_cli_output (vm, "  %v", n->name);
	}
    }
}

static clib_error_t *
set_interface_features_command_fn (vlib_main_t * vm,
				   unformat_input_t * input,
				   vlib_cli_command_t * cmd)
{
  vnet_main_t *vnm = vnet_get_main ();
  unformat_input_t _line_input, *line_input = &_line_input;
  clib_error_t *error = 0;

  u8 *arc_name = 0;
  u8 *feature_name = 0;
  u32 sw_if_index = ~0;
  u8 enable = 1;

  /* Get a line of input. */
  if (!unformat_user (input, unformat_line_input, line_input))
    goto done;

  while (unformat_check_input (line_input) != UNFORMAT_END_OF_INPUT)
    {
      if (unformat
	  (line_input, "%U %v", unformat_vnet_sw_interface, vnm, &sw_if_index,
	   &feature_name))
	;
      else if (unformat (line_input, "arc %v", &arc_name))
	;
      else if (unformat (line_input, "disable"))
	enable = 0;
      else
	{
	  error = unformat_parse_error (line_input);
	  goto done;
	}
    }

  if (sw_if_index == ~0)
    {
      error = clib_error_return (0, "Interface not specified...");
      goto done;
    }

  vec_add1 (arc_name, 0);
  vec_add1 (feature_name, 0);

  vnet_feature_registration_t *reg;
  reg =
    vnet_get_feature_reg ((const char *) arc_name,
			  (const char *) feature_name);
  if (reg == 0)
    {
      error = clib_error_return (0, "Unknown feature...");
      goto done;
    }
  if (reg->enable_disable_cb)
    error = reg->enable_disable_cb (sw_if_index, enable);
  if (!error)
    vnet_feature_enable_disable ((const char *) arc_name,
				 (const char *) feature_name, sw_if_index,
				 enable, 0, 0);

done:
  vec_free (feature_name);
  vec_free (arc_name);
  return error;
}

/*?
 * Set feature for given interface
 *
 * @cliexpar
 * Example:
 * @cliexcmd{set interface feature GigabitEthernet2/0/0 ip4_flow_classify arc ip4_unicast}
 * @cliexend
 * @endparblock
?*/
/* *INDENT-OFF* */
VLIB_CLI_COMMAND (set_interface_feature_command, static) = {
  .path = "set interface feature",
  .short_help = "set interface feature <intfc> <feature_name> arc <arc_name>",
  .function = set_interface_features_command_fn,
};
/* *INDENT-ON* */

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */