/* SPDX-License-Identifier: GPL-3.0-or-later

 * Copyright © 2016-2025 The TokTok team.

 * Copyright © 2014 Tox project.

 */

/**

 * Connection to friends.

 */

#ifndef C_TOXCORE_TOXCORE_FRIEND_CONNECTION_H

#define C_TOXCORE_TOXCORE_FRIEND_CONNECTION_H

#include <stdint.h>

#include "DHT.h"

#include "attributes.h"

#include "logger.h"

#include "mem.h"

#include "mono_time.h"

#include "net_crypto.h"

#include "network.h"

#include "onion_client.h"

#define MAX_FRIEND_CONNECTION_CALLBACKS 2

#define MESSENGER_CALLBACK_INDEX 0

#define GROUPCHAT_CALLBACK_INDEX 1

#define PACKET_ID_ALIVE 16

#define PACKET_ID_SHARE_RELAYS 17

#define PACKET_ID_FRIEND_REQUESTS 18

/** Interval between the sending of ping packets. */

#define FRIEND_PING_INTERVAL 8

/** If no packets are received from friend in this time interval, kill the connection. */

#define FRIEND_CONNECTION_TIMEOUT (FRIEND_PING_INTERVAL * 4)

/** Time before friend is removed from the DHT after last hearing about him. */

#define FRIEND_DHT_TIMEOUT BAD_NODE_TIMEOUT

#define FRIEND_MAX_STORED_TCP_RELAYS (MAX_FRIEND_TCP_CONNECTIONS * 4)

/** Max number of tcp relays sent to friends */

#define MAX_SHARED_RELAYS RECOMMENDED_FRIEND_TCP_CONNECTIONS

/** How often we share our TCP relays with each friend connection */

#define SHARE_RELAYS_INTERVAL (60 * 2)

typedef enum Friendconn_Status {

    FRIENDCONN_STATUS_NONE,

    FRIENDCONN_STATUS_CONNECTING,

    FRIENDCONN_STATUS_CONNECTED,

} Friendconn_Status;

typedef struct Friend_Connections Friend_Connections;

Net_Crypto *_Nonnull friendconn_net_crypto(const Friend_Connections *_Nonnull fr_c);

/**

 * @return friendcon_id corresponding to the real public key on success.

 * @retval -1 on failure.

 */

int getfriend_conn_id_pk(const Friend_Connections *_Nonnull fr_c, const uint8_t *_Nonnull real_pk);

/** @brief Increases lock_count for the connection with friendcon_id by 1.

 *

 * @retval 0 on success.

 * @retval -1 on failure.

 */

int friend_connection_lock(const Friend_Connections *_Nonnull fr_c, int friendcon_id);

/**

 * @retval FRIENDCONN_STATUS_CONNECTED if the friend is connected.

 * @retval FRIENDCONN_STATUS_CONNECTING if the friend isn't connected.

 * @retval FRIENDCONN_STATUS_NONE on failure.

 */

unsigned int friend_con_connected(const Friend_Connections *_Nonnull fr_c, int friendcon_id);

/** @brief Copy public keys associated to friendcon_id.

 *

 * @retval 0 on success.

 * @retval -1 on failure.

 */

int get_friendcon_public_keys(uint8_t *_Nullable real_pk, uint8_t *_Nullable dht_temp_pk, const Friend_Connections *_Nonnull fr_c, int friendcon_id);

/** Set temp dht key for connection. */

void set_dht_temp_pk(Friend_Connections *_Nonnull fr_c, int friendcon_id, const uint8_t *_Nonnull dht_temp_pk, void *_Nonnull userdata);

typedef int global_status_cb(void *_Nullable object, int friendcon_id, bool status, void *_Nullable userdata);

typedef int fc_status_cb(void *_Nullable object, int friendcon_id, bool status, void *_Nullable userdata);

typedef int fc_data_cb(void *_Nullable object, int friendcon_id, const uint8_t *_Nonnull data, uint16_t length, void *_Nullable userdata);

typedef int fc_lossy_data_cb(void *_Nullable object, int friendcon_id, const uint8_t *_Nonnull data, uint16_t length, void *_Nullable userdata);

/** Set global status callback for friend connections. */

void set_global_status_callback(Friend_Connections *_Nonnull fr_c, global_status_cb *_Nullable global_status_callback, void *_Nullable object);

/** @brief Set the callbacks for the friend connection.

 * @param index is the index (0 to (MAX_FRIEND_CONNECTION_CALLBACKS - 1)) we

 *   want the callback to set in the array.

 *

 * @retval 0 on success.

 * @retval -1 on failure

 */

int friend_connection_callbacks(const Friend_Connections *_Nonnull fr_c, int friendcon_id, unsigned int index,

                                fc_status_cb *_Nullable status_callback,

                                fc_data_cb *_Nullable data_callback,

                                fc_lossy_data_cb *_Nullable lossy_data_callback,

                                void *_Nullable object, int number);

/** @brief return the crypt_connection_id for the connection.

 *

 * @return crypt_connection_id on success.

 * @retval -1 on failure.

 */

int friend_connection_crypt_connection_id(const Friend_Connections *_Nonnull fr_c, int friendcon_id);

/** @brief Create a new friend connection.

 * If one to that real public key already exists, increase lock count and return it.

 *

 * @retval -1 on failure.

 * @return connection id on success.

 */

int new_friend_connection(Friend_Connections *_Nonnull fr_c, const uint8_t *_Nonnull real_public_key);

/** @brief Kill a friend connection.

 *

 * @retval -1 on failure.

 * @retval 0 on success.

 */

int kill_friend_connection(Friend_Connections *_Nonnull fr_c, int friendcon_id);

/** @brief Send a Friend request packet.

 *

 * @retval -1 if failure.

 * @retval  0 if it sent the friend request directly to the friend.

 * @return the number of peers it was routed through if it did not send it directly.

 */

int send_friend_request_packet(Friend_Connections *_Nonnull fr_c, int friendcon_id, uint32_t nospam_num, const uint8_t *_Nonnull data, uint16_t length);

typedef int fr_request_cb(

    void *_Nonnull object, const uint8_t *_Nonnull source_pubkey, const uint8_t *_Nonnull data, uint16_t length, void *_Nullable userdata);

/** @brief Set friend request callback.

 *

 * This function will be called every time a friend request packet is received.

 */

void set_friend_request_callback(Friend_Connections *_Nonnull fr_c, fr_request_cb *_Nonnull fr_request_callback, void *_Nonnull object);

/** Create new friend_connections instance. */

Friend_Connections *_Nullable new_friend_connections(const Logger *_Nonnull logger, const Memory *_Nonnull mem, const Mono_Time *_Nonnull mono_time, const Network *_Nonnull ns,

        Onion_Client *_Nonnull onion_c, bool local_discovery_enabled);

/** main friend_connections loop. */

void do_friend_connections(Friend_Connections *_Nonnull fr_c, void *_Nonnull userdata);

/** Free everything related with friend_connections. */

void kill_friend_connections(Friend_Connections *_Nullable fr_c);

typedef struct Friend_Conn Friend_Conn;

Friend_Conn *_Nullable get_conn(const Friend_Connections *_Nonnull fr_c, int friendcon_id);

int friend_conn_get_onion_friendnum(const Friend_Conn *_Nonnull fc);

const IP_Port *_Nullable friend_conn_get_dht_ip_port(const Friend_Conn *_Nonnull fc);

#endif /* C_TOXCORE_TOXCORE_FRIEND_CONNECTION_H */