/* Copyright (c) 2006-2012. The SimGrid Team.
 * All rights reserved.                                                     */

/* This program is free software; you can redistribute it and/or modify it
 * under the terms of the license (GNU LGPL) which comes with this package. */

#include "private.h"
#include "simdag/simdag.h"
#include "xbt/dict.h"
#include "xbt/sysdep.h"
#include "surf/surf.h"
#include "surf/surf_resource.h"


/* Creates a link and registers it in SD.
 */
SD_link_t __SD_link_create(void *surf_link, void *data)
{

  SD_link_t link;
  const char *name;

  link = xbt_new(s_SD_link_t, 1);
  link->surf_link = surf_link;
  link->data = data;            /* user data */
  if (surf_workstation_model->extension.workstation.link_shared(surf_link))
    link->sharing_policy = SD_LINK_SHARED;
  else
    link->sharing_policy = SD_LINK_FATPIPE;

  name = SD_link_get_name(link);
  xbt_lib_set(link_lib,name,SD_LINK_LEVEL,link);

  return link;
}

/**
 * \brief Returns the link list
 *
 * Use SD_link_get_number() to know the array size.
 *
 * \return an array of \ref SD_link_t containing all links
 * \see SD_link_get_number()
 */
const SD_link_t *SD_link_get_list(void)
{

  xbt_lib_cursor_t cursor;
  char *key;
  void **data;
  int i;

  if (sd_global->link_list == NULL) {   /* this is the first time the function is called */
    sd_global->link_list = xbt_new(SD_link_t, xbt_lib_length(link_lib));

    i = 0;
    xbt_lib_foreach(link_lib, cursor, key, data) {
        sd_global->link_list[i++] = (SD_link_t) data[SD_LINK_LEVEL];
    }
  }
  return sd_global->link_list;
}

/**
 * \brief Returns the number of links
 *
 * \return the number of existing links
 * \see SD_link_get_list()
 */
int SD_link_get_number(void)
{
  return xbt_lib_length(link_lib);
}

/**
 * \brief Returns the user data of a link
 *
 * \param link a link
 * \return the user data associated with this link (can be \c NULL)
 * \see SD_link_set_data()
 */
void *SD_link_get_data(SD_link_t link)
{
  return link->data;
}

/**
 * \brief Sets the user data of a link
 *
 * The new data can be \c NULL. The old data should have been freed first
 * if it was not \c NULL.
 *
 * \param link a link
 * \param data the new data you want to associate with this link
 * \see SD_link_get_data()
 */
void SD_link_set_data(SD_link_t link, void *data)
{
  link->data = data;
}

/**
 * \brief Returns the name of a link
 *
 * \param link a link
 * \return the name of this link (cannot be \c NULL)
 */
const char *SD_link_get_name(SD_link_t link)
{
  return surf_resource_name(link->surf_link);
}

/**
 * \brief Returns the current bandwidth of a link
 *
 * \param link a link
 * \return the current bandwidth of this link, in bytes per second
 */
double SD_link_get_current_bandwidth(SD_link_t link)
{
  return surf_workstation_model->extension.workstation.
      get_link_bandwidth(link->surf_link);
}

/**
 * \brief Returns the current latency of a link
 *
 * \param link a link
 * \return the current latency of this link, in seconds
 */
double SD_link_get_current_latency(SD_link_t link)
{
  return surf_workstation_model->extension.workstation.
      get_link_latency(link->surf_link);
}

/**
 * \brief Returns the sharing policy of this workstation.
 *
 * \param link a link
 * \return the sharing policyfor the flows going through this link:
 * SD_LINK_SHARED or SD_LINK_FATPIPE
 *
 */
e_SD_link_sharing_policy_t SD_link_get_sharing_policy(SD_link_t link)
{
  return link->sharing_policy;
}
