/* tox.h
 *
 * The Tox public API.
 *
 *  Copyright (C) 2013 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 TOX_H
#define TOX_H

#include <stdint.h>

#ifdef __cplusplus
extern "C" {
#endif

#define TOX_MAX_NAME_LENGTH 128
#define TOX_MAX_STATUSMESSAGE_LENGTH 128
#define TOX_CLIENT_ID_SIZE 32

#define TOX_FRIEND_ADDRESS_SIZE (TOX_CLIENT_ID_SIZE + sizeof(uint32_t) + sizeof(uint16_t))


typedef union {
    uint8_t c[4];
    uint16_t s[2];
    uint32_t i;
} tox_IP;

typedef struct {
    tox_IP ip;
    uint16_t port;
    /* not used for anything right now */
    uint16_t padding;
} tox_IP_Port;

/* status definitions */
enum {
    TOX_NOFRIEND,
    TOX_FRIEND_ADDED,
    TOX_FRIEND_REQUESTED,
    TOX_FRIEND_CONFIRMED,
    TOX_FRIEND_ONLINE,
};

/* errors for m_addfriend
 *  FAERR - Friend Add Error */
enum {
    TOX_FAERR_TOOLONG = -1,
    TOX_FAERR_NOMESSAGE = -2,
    TOX_FAERR_OWNKEY = -3,
    TOX_FAERR_ALREADYSENT = -4,
    TOX_FAERR_UNKNOWN = -5,
    TOX_FAERR_BADCHECKSUM = -6,
    TOX_FAERR_SETNEWNOSPAM = -7,
    TOX_FAERR_NOMEM = -8
};
/* USERSTATUS
 * Represents userstatuses someone can have. */

typedef enum {
    TOX_USERSTATUS_NONE,
    TOX_USERSTATUS_AWAY,
    TOX_USERSTATUS_BUSY,
    TOX_USERSTATUS_INVALID
}
TOX_USERSTATUS;

typedef void Tox;

/*
 * returns a FRIEND_ADDRESS_SIZE byte address to give to others.
 * format: [client_id (32 bytes)][nospam number (4 bytes)][checksum (2 bytes)]
 *
 */
void tox_getaddress(Tox *tox, uint8_t *address);

/*
 * add a friend
 * set the data that will be sent along with friend request
 * address is the address of the friend (returned by getaddress of the friend you wish to add) it must be FRIEND_ADDRESS_SIZE bytes. TODO: add checksum.
 * data is the data and length is the length
 * returns the friend number if success
 * return TOX_FA_TOOLONG if message length is too long
 * return TOX_FAERR_NOMESSAGE if no message (message length must be >= 1 byte)
 * return TOX_FAERR_OWNKEY if user's own key
 * return TOX_FAERR_ALREADYSENT if friend request already sent or already a friend
 * return TOX_FAERR_UNKNOWN for unknown error
 * return TOX_FAERR_BADCHECKSUM if bad checksum in address
 * return TOX_FAERR_SETNEWNOSPAM if the friend was already there but the nospam was different
 * (the nospam for that friend was set to the new one)
 * return TOX_FAERR_NOMEM if increasing the friend list size fails
 */
int tox_addfriend(Tox *tox, uint8_t *address, uint8_t *data, uint16_t length);


/* add a friend without sending a friendrequest.
    returns the friend number if success
    return -1 if failure. */
int tox_addfriend_norequest(Tox *tox, uint8_t *client_id);

/* return the friend id associated to that client id.
    return -1 if no such friend */
int tox_getfriend_id(Tox *tox, uint8_t *client_id);

/* copies the public key associated to that friend id into client_id buffer.
    make sure that client_id is of size CLIENT_ID_SIZE.
    return 0 if success
    return -1 if failure */
int tox_getclient_id(Tox *tox, int friend_id, uint8_t *client_id);

/* remove a friend */
int tox_delfriend(Tox *tox, int friendnumber);

/*  return TOX_FRIEND_ONLINE if friend is online
    return TOX_FRIEND_CONFIRMED if friend is confirmed
    return TOX_FRIEND_REQUESTED if the friend request was sent
    return TOX_FRIEND_ADDED if the friend was added
    return TOX_NOFRIEND if there is no friend with that number */
int tox_friendstatus(Tox *tox, int friendnumber);

/* send a text chat message to an online friend
    returns the message id if packet was successfully put into the send queue
    return 0 if it was not
    you will want to retain the return value, it will be passed to your read receipt callback
    if one is received.
    m_sendmessage_withid will send a message with the id of your choosing,
    however we can generate an id for you by calling plain m_sendmessage. */
uint32_t tox_sendmessage(Tox *tox, int friendnumber, uint8_t *message, uint32_t length);
uint32_t tox_sendmessage_withid(Tox *tox, int friendnumber, uint32_t theid, uint8_t *message, uint32_t length);

/* send an action to an online friend
    returns 1 if packet was successfully put into the send queue
    return 0 if it was not */
int tox_sendaction(Tox *tox, int friendnumber, uint8_t *action, uint32_t length);

/* Set our nickname
   name must be a string of maximum MAX_NAME_LENGTH length.
   length must be at least 1 byte
   length is the length of name with the NULL terminator
   return 0 if success
   return -1 if failure */
int tox_setname(Tox *tox, uint8_t *name, uint16_t length);

/*
   Get your nickname.
   m        The messanger context to use.
   name    Pointer to a string for the name.
   nlen     The length of the string buffer.
   returns Return the length of the name, 0 on error.
*/
uint16_t tox_getselfname(Tox *tox, uint8_t *name, uint16_t nlen);

/* get name of friendnumber
    put it in name
    name needs to be a valid memory location with a size of at least MAX_NAME_LENGTH (128) bytes.
    return 0 if success
    return -1 if failure */
int tox_getname(Tox *tox, int friendnumber, uint8_t *name);

/* set our user status
    you are responsible for freeing status after
    returns 0 on success, -1 on failure */
int tox_set_statusmessage(Tox *tox, uint8_t *status, uint16_t length);
int tox_set_userstatus(Tox *tox, TOX_USERSTATUS status);

/* return the length of friendnumber's status message,
    including null
    pass it into malloc */
int tox_get_statusmessage_size(Tox *tox, int friendnumber);

/* copy friendnumber's status message into buf, truncating if size is over maxlen
    get the size you need to allocate from m_get_statusmessage_size
    The self variant will copy our own status message. */
int tox_copy_statusmessage(Tox *tox, int friendnumber, uint8_t *buf, uint32_t maxlen);
int tox_copy_self_statusmessage(Tox *tox, uint8_t *buf, uint32_t maxlen);

/* Return one of USERSTATUS values.
 * Values unknown to your application should be represented as USERSTATUS_NONE.
 * As above, the self variant will return our own USERSTATUS.
 * If friendnumber is invalid, this shall return USERSTATUS_INVALID. */
TOX_USERSTATUS tox_get_userstatus(Tox *tox, int friendnumber);
TOX_USERSTATUS tox_get_selfuserstatus(Tox *tox);

/* Sets whether we send read receipts for friendnumber.
 * This function is not lazy, and it will fail if yesno is not (0 or 1).*/
void tox_set_sends_receipts(Tox *tox, int friendnumber, int yesno);

/* set the function that will be executed when a friend request is received.
    function format is function(uint8_t * public_key, uint8_t * data, uint16_t length) */
void tox_callback_friendrequest(Tox *tox, void (*function)(uint8_t *, uint8_t *, uint16_t, void *), void *userdata);

/* set the function that will be executed when a message from a friend is received.
    function format is: function(int friendnumber, uint8_t * message, uint32_t length) */
void tox_callback_friendmessage(Tox *tox, void (*function)(Tox *tox, int, uint8_t *, uint16_t, void *),
                                void *userdata);

/* set the function that will be executed when an action from a friend is received.
    function format is: function(int friendnumber, uint8_t * action, uint32_t length) */
void tox_callback_action(Tox *tox, void (*function)(Tox *tox, int, uint8_t *, uint16_t, void *), void *userdata);

/* set the callback for name changes
    function(int friendnumber, uint8_t *newname, uint16_t length)
    you are not responsible for freeing newname */
void tox_callback_namechange(Tox *tox, void (*function)(Tox *tox, int, uint8_t *, uint16_t, void *),
                             void *userdata);

/* set the callback for status message changes
    function(int friendnumber, uint8_t *newstatus, uint16_t length)
    you are not responsible for freeing newstatus */
void tox_callback_statusmessage(Tox *tox, void (*function)(Tox *tox, int, uint8_t *, uint16_t, void *),
                                void *userdata);

/* set the callback for status type changes
    function(int friendnumber, USERSTATUS kind) */
void tox_callback_userstatus(Tox *tox, void (*function)(Tox *tox, int, TOX_USERSTATUS, void *), void *userdata);

/* set the callback for read receipts
    function(int friendnumber, uint32_t receipt)
    if you are keeping a record of returns from m_sendmessage,
    receipt might be one of those values, and that means the message
    has been received on the other side. since core doesn't
    track ids for you, receipt may not correspond to any message
    in that case, you should discard it. */
void tox_callback_read_receipt(Tox *tox, void (*function)(Tox *tox, int, uint32_t, void *), void *userdata);

/* set the callback for connection status changes
    function(int friendnumber, uint8_t status)
    status:
      0 -- friend went offline after being previously online
      1 -- friend went online
    note that this callback is not called when adding friends, thus the "after
    being previously online" part. it's assumed that when adding friends,
    their connection status is offline. */
void tox_callback_connectionstatus(Tox *tox, void (*function)(Tox *tox, int, uint8_t, void *), void *userdata);

/* Use this function to bootstrap the client
    Sends a get nodes request to the given node with ip port and public_key */
void tox_bootstrap(Tox *tox, tox_IP_Port ip_port, uint8_t *public_key);

/* returns 0 if we are not connected to the DHT
    returns 1 if we are */
int tox_isconnected(Tox *tox);

/* run this at startup
 *  returns allocated instance of tox on success
 *  returns 0 if there are problems */
Tox *tox_new(void);

/* run this before closing shop
 * free all datastructures */
void tox_kill(Tox *tox);

/* the main loop that needs to be run at least 20 times per second */
void tox_do(Tox *tox);

/* SAVING AND LOADING FUNCTIONS: */

/* returns the size of the messenger data (for saving) */
uint32_t tox_size(Tox *tox);

/* save the messenger in data (must be allocated memory of size Messenger_size()) */
void tox_save(Tox *tox, uint8_t *data);

/* load the messenger from data of size length */
int tox_load(Tox *tox, uint8_t *data, uint32_t length);


#ifdef __cplusplus
}
#endif

#endif