/*
   This file is part of GNUnet.
   Copyright (C) 2020 GNUnet e.V.

   GNUnet is free software: you can redistribute it and/or modify it
   under the terms of the GNU Affero General Public License as published
   by the Free Software Foundation, either version 3 of the License,
   or (at your option) any later version.

   GNUnet 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
   Affero General Public License for more details.

   You should have received a copy of the GNU Affero General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.

   SPDX-License-Identifier: AGPL3.0-or-later
 */
/**
 * @author Tobias Frisch
 * @file src/messenger/messenger_api_handle.c
 * @brief messenger api: client implementation of GNUnet MESSENGER service
 */

#include "messenger_api_handle.h"

struct GNUNET_MESSENGER_Handle*
create_handle (const struct GNUNET_CONFIGURATION_Handle *cfg, GNUNET_MESSENGER_IdentityCallback identity_callback,
               void *identity_cls, GNUNET_MESSENGER_MessageCallback msg_callback, void *msg_cls)
{
  struct GNUNET_MESSENGER_Handle *handle = GNUNET_new(struct GNUNET_MESSENGER_Handle);

  handle->cfg = cfg;
  handle->mq = NULL;

  handle->identity_callback = identity_callback;
  handle->identity_cls = identity_cls;

  handle->msg_callback = msg_callback;
  handle->msg_cls = msg_cls;

  handle->name = NULL;
  handle->pubkey = NULL;

  handle->reconnect_time = GNUNET_TIME_relative_get_zero_ ();
  handle->reconnect_task = NULL;

  handle->rooms = GNUNET_CONTAINER_multihashmap_create (8, GNUNET_NO);
  handle->contacts = GNUNET_CONTAINER_multihashmap_create (8, GNUNET_NO);

  return handle;
}

static int
iterate_destroy_room (void *cls, const struct GNUNET_HashCode *key, void *value)
{
  struct GNUNET_MESSENGER_Room *room = value;

  destroy_room (room);

  return GNUNET_YES;
}

static int
iterate_destroy_contact (void *cls, const struct GNUNET_HashCode *key, void *value)
{
  struct GNUNET_MESSENGER_Contact *contact = value;

  destroy_contact (contact);

  return GNUNET_YES;
}

void
destroy_handle (struct GNUNET_MESSENGER_Handle *handle)
{
  if (handle->reconnect_task)
    GNUNET_SCHEDULER_cancel (handle->reconnect_task);

  if (handle->mq)
    GNUNET_MQ_destroy (handle->mq);

  if (handle->name)
    GNUNET_free(handle->name);

  if (handle->pubkey)
    GNUNET_free(handle->pubkey);

  if (handle->rooms)
  {
    GNUNET_CONTAINER_multihashmap_iterate (handle->rooms, iterate_destroy_room, NULL);

    GNUNET_CONTAINER_multihashmap_destroy (handle->rooms);
  }

  if (handle->contacts)
  {
    GNUNET_CONTAINER_multihashmap_iterate (handle->contacts, iterate_destroy_contact, NULL);

    GNUNET_CONTAINER_multihashmap_destroy (handle->contacts);
  }

  GNUNET_free(handle->name);
}

void
set_handle_name (struct GNUNET_MESSENGER_Handle *handle, const char *name)
{
  if (handle->name)
    GNUNET_free(handle->name);

  handle->name = name? GNUNET_strdup(name) : NULL;
}

const char*
get_handle_name (const struct GNUNET_MESSENGER_Handle *handle)
{
  return handle->name;
}

void
set_handle_key (struct GNUNET_MESSENGER_Handle *handle, const struct GNUNET_IDENTITY_PublicKey *pubkey)
{
  if (!handle->pubkey)
    handle->pubkey = GNUNET_new(struct GNUNET_IDENTITY_PublicKey);

  GNUNET_memcpy(handle->pubkey, pubkey, sizeof(*pubkey));
}

const struct GNUNET_IDENTITY_PublicKey*
get_handle_key (const struct GNUNET_MESSENGER_Handle *handle)
{
  if (!handle->pubkey)
  {
    struct GNUNET_IDENTITY_Ego *anonymous = GNUNET_IDENTITY_ego_get_anonymous ();
    static struct GNUNET_IDENTITY_PublicKey pubkey;

    GNUNET_IDENTITY_ego_get_public_key (anonymous, &pubkey);

    return &pubkey;
  }

  return handle->pubkey;
}

struct GNUNET_MESSENGER_Contact*
get_handle_contact_by_pubkey (const struct GNUNET_MESSENGER_Handle *handle,
                              const struct GNUNET_IDENTITY_PublicKey *pubkey)
{
  struct GNUNET_HashCode hash;

  GNUNET_CRYPTO_hash (pubkey, sizeof(*pubkey), &hash);

  struct GNUNET_MESSENGER_Contact *contact = GNUNET_CONTAINER_multihashmap_get (handle->contacts, &hash);

  if (contact)
    return contact;

  contact = create_contact (pubkey);

  if (GNUNET_OK == GNUNET_CONTAINER_multihashmap_put (handle->contacts, &hash, contact,
                                                      GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST))
    return contact;

  destroy_contact (contact);
  return NULL;
}

void
swap_handle_contact_by_pubkey (struct GNUNET_MESSENGER_Handle *handle, struct GNUNET_MESSENGER_Contact *contact,
                               const struct GNUNET_IDENTITY_PublicKey *pubkey)
{
  const struct GNUNET_HashCode *hash = get_contact_id_from_key (contact);

  if (GNUNET_YES == GNUNET_CONTAINER_multihashmap_remove (handle->contacts, hash, contact))
  {
    GNUNET_memcpy(&(contact->public_key), pubkey, sizeof(*pubkey));

    hash = get_contact_id_from_key (contact);

    GNUNET_CONTAINER_multihashmap_put (handle->contacts, hash, contact,
                                       GNUNET_CONTAINER_MULTIHASHMAPOPTION_UNIQUE_FAST);
  }
}

void
open_handle_room (struct GNUNET_MESSENGER_Handle *handle, const struct GNUNET_HashCode *key)
{
  struct GNUNET_MESSENGER_Room *room = GNUNET_CONTAINER_multihashmap_get (handle->rooms, key);

  if (room)
    room->opened = GNUNET_YES;
}

void
entry_handle_room_at (struct GNUNET_MESSENGER_Handle *handle, const struct GNUNET_PeerIdentity *door,
                      const struct GNUNET_HashCode *key)
{
  struct GNUNET_MESSENGER_Room *room = GNUNET_CONTAINER_multihashmap_get (handle->rooms, key);

  if (room)
    add_to_list_tunnels (&(room->entries), door);
}

void
close_handle_room (struct GNUNET_MESSENGER_Handle *handle, const struct GNUNET_HashCode *key)
{
  struct GNUNET_MESSENGER_Room *room = GNUNET_CONTAINER_multihashmap_get (handle->rooms, key);

  if ((room) && (GNUNET_YES == GNUNET_CONTAINER_multihashmap_remove (handle->rooms, key, room)))
    destroy_room (room);
}