/* friend_connection.h
 *
 * Connection to friends.
 *
 *  Copyright (C) 2014 Tox project All Rights Reserved.
 *
 *  This file is part of Tox.
 *
 *  Tox is free software: you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation, either version 3 of the License, or
 *  (at your option) any later version.
 *
 *  Tox 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 General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with Tox.  If not, see <http://www.gnu.org/licenses/>.
 *
 */


#ifndef FRIEND_CONNECTION_H
#define FRIEND_CONNECTION_H

#include "net_crypto.h"
#include "DHT.h"
#include "LAN_discovery.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

/* Interval between the sending of ping packets. */
#define FRIEND_PING_INTERVAL 6

/* If no packets are received from friend in this time interval, kill the connection. */
#define FRIEND_CONNECTION_TIMEOUT (FRIEND_PING_INTERVAL * 3)

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


enum {
    FRIENDCONN_STATUS_NONE,
    FRIENDCONN_STATUS_CONNECTING,
    FRIENDCONN_STATUS_CONNECTED
};

typedef struct {
    uint8_t status;

    uint8_t real_public_key[crypto_box_PUBLICKEYBYTES];
    uint8_t dht_temp_pk[crypto_box_PUBLICKEYBYTES];
    uint16_t dht_lock;
    IP_Port dht_ip_port;
    uint64_t dht_ping_lastrecv, dht_ip_port_lastrecv;

    int onion_friendnum;
    int crypt_connection_id;

    uint64_t ping_lastrecv, ping_lastsent;

    struct {
        int (*status_callback)(void *object, int id, uint8_t status);
        void *status_callback_object;
        int status_callback_id;

        int (*data_callback)(void *object, int id, uint8_t *data, uint16_t length);
        void *data_callback_object;
        int data_callback_id;

        int (*lossy_data_callback)(void *object, int id, const uint8_t *data, uint16_t length);
        void *lossy_data_callback_object;
        int lossy_data_callback_id;
    } callbacks[MAX_FRIEND_CONNECTION_CALLBACKS];

    uint16_t lock_count;
} Friend_Conn;


typedef struct {
    Net_Crypto *net_crypto;
    DHT *dht;
    Onion_Client *onion_c;

    Friend_Conn *conns;
    uint32_t num_cons;

} Friend_Connections;

/* Set the callbacks for the friend connection.
 * index is the index (0 to (MAX_FRIEND_CONNECTION_CALLBACKS - 1)) we want the callback to set in the array.
 *
 * return 0 on success.
 * return -1 on failure
 */
int friend_connection_callbacks(Friend_Connections *fr_c, int friendcon_id, unsigned int index,
                                int (*status_callback)(void *object, int id, uint8_t status), int (*data_callback)(void *object, int id, uint8_t *data,
                                        uint16_t length), int (*lossy_data_callback)(void *object, int id, const uint8_t *data, uint16_t length), void *object,
                                int number);

/* return the crypt_connection_id for the connection.
 *
 * return crypt_connection_id on success.
 * return -1 on failure.
 */
int friend_connection_crypt_connection_id(Friend_Connections *fr_c, int friendcon_id);

/* Create a new friend connection.
 * If one to that real public key already exists, increase lock count and return it.
 *
 * return -1 on failure.
 * return connection id on success.
 */
int new_friend_connection(Friend_Connections *fr_c, const uint8_t *real_public_key);

/* Kill a friend connection.
 *
 * return -1 on failure.
 * return 0 on success.
 */
int kill_friend_connection(Friend_Connections *fr_c, int friendcon_id);

/* Create new friend_connections instance. */
Friend_Connections *new_friend_connections(Onion_Client *onion_c);

/* main friend_connections loop. */
void do_friend_connections(Friend_Connections *fr_c);

/* Free everything related with friend_connections. */
void kill_friend_connections(Friend_Connections *fr_c);

#endif