toxic/src/audio_call.c

/*  audio_call.c
 *
 *
 *  Copyright (C) 2014 Toxic All Rights Reserved.
 *
 *  This file is part of Toxic.
 *
 *  Toxic 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.
 *
 *  Toxic 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 Toxic.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#include "toxic.h"
#include "windows.h"
#include "audio_call.h"
#include "audio_device.h"
#include "chat_commands.h"
#include "global_commands.h"
#include "line_info.h"
#include "notify.h"
#include "friendlist.h"
#include "chat.h"

#ifdef VIDEO
#include "video_call.h"
#endif /* VIDEO */

#include <stdbool.h>
#include <curses.h>
#include <string.h>
#include <pthread.h>
#include <unistd.h>
#include <stdlib.h>
#include <assert.h>

#ifdef __APPLE__
#include <OpenAL/al.h>
#include <OpenAL/alc.h>
#else
#include <AL/al.h>
#include <AL/alc.h>
/* compatibility with older versions of OpenAL */
#ifndef ALC_ALL_DEVICES_SPECIFIER
#include <AL/alext.h>
#endif
#endif

extern FriendsList Friends;
struct CallControl CallControl;

#define cbend pthread_exit(NULL)

#define frame_size (CallControl.audio_sample_rate * CallControl.audio_frame_duration / 1000)

static int set_call(Call *call, bool start)
{
    call->in_idx = -1;
    call->out_idx = -1;
#ifdef VIDEO
    call->vin_idx = -1;
    call->vout_idx = -1;
#endif /* VIDEO */

    if ( start ) {
        call->ttas = true;

        if ( pthread_mutex_init(&call->mutex, NULL) != 0 )
            return -1;
    } else {
        call->ttid = 0;

        if ( pthread_mutex_destroy(&call->mutex) != 0 )
            return -1;
    }

    return 0;
}

void call_cb                 ( ToxAV *av, uint32_t friend_number, bool audio_enabled, bool video_enabled,
                               void *user_data );
void callstate_cb            ( ToxAV *av, uint32_t friend_number, uint32_t state, void *user_data );
void receive_audio_frame_cb  ( ToxAV *av, uint32_t friend_number, int16_t const *pcm, size_t sample_count,
                               uint8_t channels, uint32_t sampling_rate, void *user_data );
void receive_video_frame_cb  ( ToxAV *av, uint32_t friend_number,
                               uint16_t width, uint16_t height,
                               uint8_t const *y, uint8_t const *u, uint8_t const *v, uint8_t const *a,
                               int32_t ystride, int32_t ustride, int32_t vstride, int32_t astride, void *user_data );

void callback_recv_invite   ( Tox *m, uint32_t friend_number );
void callback_recv_ringing  ( uint32_t friend_number );
void callback_recv_starting ( uint32_t friend_number );
void callback_recv_ending   ( uint32_t friend_number );
void callback_call_started  ( uint32_t friend_number );
void callback_call_canceled ( uint32_t friend_number );
void callback_call_rejected ( uint32_t friend_number );
void callback_call_ended    ( uint32_t friend_number );

void write_device_callback( uint32_t friend_number, const int16_t *PCM, uint16_t sample_count, uint8_t channels,
                            uint32_t sample_rate );

static void print_err (ToxWindow *self, const char *error_str)
{
    line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "%s", error_str);
}

ToxAV *init_audio(ToxWindow *self, Tox *tox)
{
    TOXAV_ERR_NEW error;
    CallControl.audio_errors = ae_None;
    CallControl.prompt = self;
    CallControl.pending_call = false;

    CallControl.av = toxav_new(tox, &error);

    CallControl.audio_enabled = true;
    CallControl.audio_bit_rate = 64;
    CallControl.audio_sample_rate = 48000;
    CallControl.audio_frame_duration = 20;
    CallControl.audio_channels = 1;

#ifndef VIDEO
    CallControl.video_enabled = false;
    CallControl.video_bit_rate = 0;
    CallControl.video_frame_duration = 0;
#endif /* VIDEO */

    if ( !CallControl.av ) {
        CallControl.audio_errors |= ae_StartingCoreAudio;
        line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "Failed to init ToxAV");

        return NULL;
    }

    if ( init_devices(CallControl.av) == de_InternalError ) {
        line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "Failed to init devices");
        toxav_kill(CallControl.av);

        return CallControl.av = NULL;
    }

    toxav_callback_call(CallControl.av, call_cb, tox);
    toxav_callback_call_state(CallControl.av, callstate_cb, NULL);
    toxav_callback_audio_receive_frame(CallControl.av, receive_audio_frame_cb, NULL);

    return CallControl.av;
}

void terminate_audio()
{
    int i;

    for (i = 0; i < CallControl.max_calls; ++i)
        stop_transmission(&CallControl.calls[i], i);

    if ( CallControl.av )
        toxav_kill(CallControl.av);

    terminate_devices();
}

void read_device_callback(const int16_t *captured, uint32_t size, void *data)
{
    TOXAV_ERR_SEND_FRAME error;
    uint32_t friend_number = *((uint32_t *)data); /* TODO: Or pass an array of call_idx's */
    int64_t sample_count = ((int64_t) CallControl.audio_sample_rate) * \
                           ((int64_t) CallControl.audio_frame_duration) / 1000;

    if ( sample_count <= 0 || toxav_audio_send_frame(CallControl.av, friend_number,
            captured, sample_count,
            CallControl.audio_channels,
            CallControl.audio_sample_rate, &error) == false ) {
    }
}

void write_device_callback(uint32_t friend_number, const int16_t *PCM, uint16_t sample_count, uint8_t channels,
                           uint32_t sample_rate)
{
    if ( CallControl.calls[friend_number].ttas )
        write_out(CallControl.calls[friend_number].out_idx, PCM, sample_count, channels, sample_rate);
}

int start_transmission(ToxWindow *self, Call *call)
{
    if ( !self || !CallControl.av ) {
        line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "Failed to prepare transmission");
        return -1;
    }

    if (set_call(call, true) == -1)
        return -1;

    DeviceError error = open_primary_device(input, &call->in_idx,
                                            CallControl.audio_sample_rate, CallControl.audio_frame_duration, CallControl.audio_channels);

    if ( error != de_None ) {
        if ( error == de_FailedStart)
            line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "Failed to start input device");

        if ( error == de_InternalError )
            line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "Internal error with opening input device");
    }

    if ( register_device_callback(self->num, call->in_idx,
                                  read_device_callback, &self->num, true) != de_None)
        /* Set VAD as true for all; TODO: Make it more dynamic */
        line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "Failed to register input handler!");

    if ( open_primary_device(output, &call->out_idx,
                             CallControl.audio_sample_rate, CallControl.audio_frame_duration, CallControl.audio_channels) != de_None ) {
        line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "Failed to open output device!");
        call->has_output = 0;
    }

    return 0;
}

int stop_transmission(Call *call, uint32_t friend_number)
{
    if ( call->ttas ) {
        TOXAV_ERR_CALL_CONTROL error = TOXAV_ERR_CALL_CONTROL_OK;

        if ( CallControl.call_state > TOXAV_FRIEND_CALL_STATE_FINISHED )
            toxav_call_control(CallControl.av, friend_number, TOXAV_CALL_CONTROL_CANCEL, &error);

        if ( error == TOXAV_ERR_CALL_CONTROL_OK ) {
            call->ttas = false;

            if ( call->in_idx != -1 )
                close_device(input, call->in_idx);

            if ( call->out_idx != -1 )
                close_device(output, call->out_idx);

            if ( set_call(call, false) == -1 )
                return -1;

            return 0;
        } else {

            return -1;
        }
    }

    return -1;
}
/*
 * End of transmission
 */





/*
 * Callbacks
 */
void call_cb(ToxAV *av, uint32_t friend_number, bool audio_enabled, bool video_enabled, void *user_data)
{
    Tox *m = (Tox *) user_data;
    CallControl.pending_call = true;
    callback_recv_invite(m, friend_number);
}

void callstate_cb(ToxAV *av, uint32_t friend_number, uint32_t state, void *user_data)
{
    CallControl.call_state = state;

    switch ( state ) {
        case ( TOXAV_FRIEND_CALL_STATE_ERROR ):
            line_info_add(CallControl.prompt, NULL, NULL, NULL, SYS_MSG, 0, 0, "ToxAV callstate error!");

#ifdef VIDEO
            callback_video_end(friend_number);
#endif /* VIDEO */

            stop_transmission(&CallControl.calls[friend_number], friend_number);
            callback_call_ended(friend_number);
            CallControl.pending_call = false;

            break;

        case ( TOXAV_FRIEND_CALL_STATE_FINISHED ):
            if ( CallControl.pending_call )
                callback_call_rejected(friend_number);
            else
                callback_call_ended(friend_number);

#ifdef VIDEO
            callback_recv_video_end(friend_number);
            callback_video_end(friend_number);
#endif /* VIDEO */

            stop_transmission(&CallControl.calls[friend_number], friend_number);

            /* Reset stored call state after finishing */
            CallControl.call_state = 0;
            CallControl.pending_call = false;

            break;

        default:
            if ( CallControl.pending_call ) {
                /* Start answered call */
                callback_call_started(friend_number);
                CallControl.pending_call = false;

            } else {
#ifdef VIDEO

                /* Handle receiving client video call states */
                if ( state & TOXAV_FRIEND_CALL_STATE_SENDING_V )
                    callback_recv_video_starting(friend_number);
                else if ( state & ~TOXAV_FRIEND_CALL_STATE_SENDING_V )
                    callback_recv_video_end(friend_number);

#endif /* VIDEO */
            }

            break;
    }
}

void receive_audio_frame_cb(ToxAV *av, uint32_t friend_number,
                            int16_t const *pcm, size_t sample_count,
                            uint8_t channels, uint32_t sampling_rate, void *user_data)
{
    write_device_callback(friend_number, pcm, sample_count, channels, sampling_rate);
}

void audio_bit_rate_status_cb(ToxAV *av, uint32_t friend_number, uint32_t audio_bit_rate, void *user_data)
{
    CallControl.audio_bit_rate = audio_bit_rate;
    toxav_audio_set_bit_rate(av, friend_number, audio_bit_rate, user_data);
}

void callback_recv_invite(Tox *m, uint32_t friend_number)
{
    if (friend_number >= Friends.max_idx)
        return;

    if (Friends.list[friend_number].chatwin == -1) {
        if (get_num_active_windows() >= MAX_WINDOWS_NUM)
            return;

        Friends.list[friend_number].chatwin = add_window(m, new_chat(m, Friends.list[friend_number].num));
    }

    ToxWindow *windows = CallControl.prompt;
    int i;

    for (i = 0; i < MAX_WINDOWS_NUM; ++i) {
        if (windows[i].onInvite != NULL && windows[i].num == friend_number) {
            windows[i].onInvite(&windows[i], CallControl.av, friend_number, CallControl.call_state);
        }
    }
}
void callback_recv_ringing(uint32_t friend_number)
{
    ToxWindow *windows = CallControl.prompt;
    int i;

    for (i = 0; i < MAX_WINDOWS_NUM; ++i) {
        if (windows[i].onRinging != NULL && windows[i].num == friend_number) {
            windows[i].onRinging(&windows[i], CallControl.av, friend_number, CallControl.call_state);
        }
    }
}
void callback_recv_starting(uint32_t friend_number)
{
    ToxWindow *windows = CallControl.prompt;

    int i;

    for (i = 0; i < MAX_WINDOWS_NUM; ++i) {
        if ( windows[i].onStarting != NULL && windows[i].num == friend_number ) {
            windows[i].onStarting(&windows[i], CallControl.av, friend_number, CallControl.call_state);

            if ( 0 != start_transmission(&windows[i], &CallControl.calls[friend_number]) ) /* YEAH! */
                line_info_add(&windows[i], NULL, NULL, NULL, SYS_MSG, 0, 0, "Error starting transmission!");

            return;
        }
    }
}
void callback_recv_ending(uint32_t friend_number)
{
    ToxWindow *windows = CallControl.prompt;
    int i;

    for (i = 0; i < MAX_WINDOWS_NUM; ++i) {
        if (windows[i].onEnding != NULL && windows[i].num == friend_number) {
            windows[i].onEnding(&windows[i], CallControl.av, friend_number, CallControl.call_state);
        }
    }
}
void callback_call_started(uint32_t friend_number)
{
    ToxWindow *windows = CallControl.prompt;

    int i;

    for (i = 0; i < MAX_WINDOWS_NUM; ++i)
        if ( windows[i].onStart != NULL && windows[i].num == friend_number ) {
            windows[i].onStart(&windows[i], CallControl.av, friend_number, CallControl.call_state);

            if ( 0 != start_transmission(&windows[i], &CallControl.calls[friend_number]) ) {/* YEAH! */
                line_info_add(&windows[i], NULL, NULL, NULL, SYS_MSG, 0, 0, "Error starting transmission!");
                return;
            }
        }
}
void callback_call_canceled(uint32_t friend_number)
{
    ToxWindow *windows = CallControl.prompt;
    int i;

    for (i = 0; i < MAX_WINDOWS_NUM; ++i) {
        if (windows[i].onCancel != NULL && windows[i].num == friend_number) {
            windows[i].onCancel(&windows[i], CallControl.av, friend_number, CallControl.call_state);
        }
    }
}
void callback_call_rejected(uint32_t friend_number)
{
    ToxWindow *windows = CallControl.prompt;
    int i;

    for (i = 0; i < MAX_WINDOWS_NUM; ++i) {
        if (windows[i].onReject != NULL && windows[i].num == friend_number) {
            windows[i].onReject(&windows[i], CallControl.av, friend_number, CallControl.call_state);
        }
    }
}
void callback_call_ended(uint32_t friend_number)
{
    ToxWindow *windows = CallControl.prompt;
    int i;

    for (i = 0; i < MAX_WINDOWS_NUM; ++i) {
        if (windows[i].onEnd != NULL && windows[i].num == friend_number) {
            windows[i].onEnd(&windows[i], CallControl.av, friend_number, CallControl.call_state);
        }
    }
}

/*
 * End of Callbacks
 */


/*
 * Commands from chat_commands.h
 */
void cmd_call(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*argv)[MAX_STR_SIZE])
{
    TOXAV_ERR_CALL error;
    const char *error_str;

    if ( argc != 0 ) {
        error_str = "Unknown arguments.";
        goto on_error;
    }

    if ( !CallControl.av ) {
        error_str = "ToxAV not supported!";
        goto on_error;
    }

    if ( !self->stb->connection ) {
        error_str = "Friend is offline.";
        goto on_error;
    }

    if ( CallControl.pending_call ) {
        error_str = "Already a pending call!";
        goto on_error;
    }

    toxav_call(CallControl.av, self->num, CallControl.audio_bit_rate, CallControl.video_bit_rate, &error);

    if ( error != TOXAV_ERR_CALL_OK ) {
        if ( error == TOXAV_ERR_CALL_FRIEND_ALREADY_IN_CALL ) error_str = "Already in a call!";
        else if ( error == TOXAV_ERR_CALL_MALLOC ) error_str = "Memory allocation issue";
        else if ( error == TOXAV_ERR_CALL_FRIEND_NOT_FOUND ) error_str = "Friend number invalid";
        else if ( error == TOXAV_ERR_CALL_FRIEND_NOT_CONNECTED ) error_str = "Friend is valid but not currently connected";
        else error_str = "Internal error!";

        goto on_error;
    }

    CallControl.pending_call = true;
    callback_recv_ringing(self->num);

    return;
on_error:
    print_err(self, error_str);
}

void cmd_answer(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*argv)[MAX_STR_SIZE])
{
    TOXAV_ERR_ANSWER error;
    const char *error_str;

    if ( argc != 0 ) {
        error_str = "Unknown arguments.";
        goto on_error;
    }

    if ( !CallControl.av ) {
        error_str = "Audio not supported!";
        goto on_error;
    }

    if ( !CallControl.pending_call ) {
        error_str = "No incoming call!";
        goto on_error;
    }

    toxav_answer(CallControl.av, self->num, CallControl.audio_bit_rate, CallControl.video_bit_rate, &error);

    if ( error != TOXAV_ERR_ANSWER_OK ) {
        if ( error == TOXAV_ERR_ANSWER_FRIEND_NOT_CALLING ) error_str = "No incoming call!";
        else if ( error == TOXAV_ERR_ANSWER_CODEC_INITIALIZATION ) error_str = "Failed to initialize codecs!";
        else if ( error == TOXAV_ERR_ANSWER_FRIEND_NOT_FOUND ) error_str = "Friend not found!";
        else if ( error == TOXAV_ERR_ANSWER_INVALID_BIT_RATE ) error_str = "Invalid bit rate!";
        else error_str = "Internal error!";

        goto on_error;
    }

    /* Callback will print status... */
    callback_recv_starting(self->num);
    CallControl.pending_call = false;

    return;
on_error:
    print_err (self, error_str);
}

void cmd_reject(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*argv)[MAX_STR_SIZE])
{
    const char *error_str;

    if ( argc != 0 ) {
        error_str = "Unknown arguments.";
        goto on_error;
    }

    if ( !CallControl.av ) {
        error_str = "Audio not supported!";
        goto on_error;
    }

    if ( !CallControl.pending_call ) {
        error_str = "No incoming call!";
        goto on_error;
    }

    /* Manually send a cancel call control because call hasn't started */
    toxav_call_control(CallControl.av, self->num, TOXAV_CALL_CONTROL_CANCEL, NULL);
    CallControl.pending_call = false;

    /* Callback will print status... */
    callback_call_rejected(self->num);

    return;
on_error:
    print_err (self, error_str);
}

void cmd_hangup(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*argv)[MAX_STR_SIZE])
{
    const char *error_str = NULL;

    if ( !CallControl.av ) {
        error_str = "Audio not supported!";
        goto on_error;
    }

    if ( argc != 0 ) {
        error_str = "Unknown arguments.";
        goto on_error;
    }

    if ( !self->is_call && !CallControl.pending_call ) {
        error_str = "Not in a call.";
        goto on_error;
    }

#ifdef VIDEO
    callback_video_end(self->num);
#endif /* VIDEO */

    stop_current_call(self);
    return;
on_error:
    print_err (self, error_str);
}

void cmd_list_devices(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*argv)[MAX_STR_SIZE])
{
    const char *error_str;

    if ( argc != 1 ) {
        if ( argc < 1 ) error_str = "Type must be specified!";
        else error_str = "Only one argument allowed!";

        goto on_error;
    }

    DeviceType type;

    if ( strcasecmp(argv[1], "in") == 0 ) /* Input devices */
        type = input;

    else if ( strcasecmp(argv[1], "out") == 0 ) /* Output devices */
        type = output;

    else {
        line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "Invalid type: %s", argv[1]);
        return;
    }

    // Refresh device list.
    get_devices_names();

    print_devices(self, type);

    return;
on_error:
    print_err (self, error_str);
}

/* This changes primary device only */
void cmd_change_device(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*argv)[MAX_STR_SIZE])
{
    const char *error_str;

    if ( argc != 2 ) {
        if ( argc < 1 ) error_str = "Type must be specified!";
        else if ( argc < 2 ) error_str = "Must have id!";
        else error_str = "Only two arguments allowed!";

        goto on_error;
    }

    DeviceType type;

    if ( strcmp(argv[1], "in") == 0 ) /* Input devices */
        type = input;

    else if ( strcmp(argv[1], "out") == 0 ) /* Output devices */
        type = output;

    else {
        line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "Invalid type: %s", argv[1]);
        return;
    }


    char *end;
    long int selection = strtol(argv[2], &end, 10);

    if ( *end ) {
        error_str = "Invalid input";
        goto on_error;
    }

    if ( set_primary_device(type, selection) == de_InvalidSelection ) {
        error_str = "Invalid selection!";
        goto on_error;
    }

    return;
on_error:
    print_err (self, error_str);
}

void cmd_ccur_device(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*argv)[MAX_STR_SIZE])
{
    const char *error_str;

    if ( argc != 2 ) {
        if ( argc < 1 ) error_str = "Type must be specified!";
        else if ( argc < 2 ) error_str = "Must have id!";
        else error_str = "Only two arguments allowed!";

        goto on_error;
    }

    DeviceType type;

    if ( strcmp(argv[1], "in") == 0 ) /* Input devices */
        type = input;

    else if ( strcmp(argv[1], "out") == 0 ) /* Output devices */
        type = output;

    else {
        line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "Invalid type: %s", argv[1]);
        return;
    }


    char *end;
    long int selection = strtol(argv[2], &end, 10);

    if ( *end ) {
        error_str = "Invalid input";
        goto on_error;
    }

    if ( selection_valid(type, selection) == de_InvalidSelection ) {
        error_str = "Invalid selection!";
        goto on_error;
    }

    /* If call is active, change device */
    if ( self->is_call ) {
        Call *this_call = &CallControl.calls[self->num];

        if ( this_call->ttas ) {


            if ( type == output ) {
                pthread_mutex_lock(&this_call->mutex);
                close_device(output, this_call->out_idx);
                this_call->has_output = open_device(output, selection, &this_call->out_idx,
                                                    CallControl.audio_sample_rate, CallControl.audio_frame_duration, CallControl.audio_channels)
                                        == de_None ? 1 : 0;
                pthread_mutex_unlock(&this_call->mutex);
            } else {
                /* TODO: check for failure */
                close_device(input, this_call->in_idx);
                open_device(input, selection, &this_call->in_idx, CallControl.audio_sample_rate,
                            CallControl.audio_frame_duration, CallControl.audio_channels);
                /* Set VAD as true for all; TODO: Make it more dynamic */
                register_device_callback(self->num, this_call->in_idx, read_device_callback, &self->num, true);
            }
        }
    }

    self->device_selection[type] = selection;

    return;
on_error:
    print_err (self, error_str);
}

void cmd_mute(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*argv)[MAX_STR_SIZE])
{
    const char *error_str;

    if ( argc != 1 ) {
        if ( argc < 1 ) error_str = "Type must be specified!";
        else error_str = "Only two arguments allowed!";

        goto on_error;
    }

    DeviceType type;

    if ( strcasecmp(argv[1], "in") == 0 ) /* Input devices */
        type = input;

    else if ( strcasecmp(argv[1], "out") == 0 ) /* Output devices */
        type = output;

    else {
        line_info_add(self, NULL, NULL, NULL, SYS_MSG, 0, 0, "Invalid type: %s", argv[1]);
        return;
    }


    /* If call is active, use this_call values */
    if ( self->is_call ) {
        Call *this_call = &CallControl.calls[self->num];

        pthread_mutex_lock(&this_call->mutex);

        if ( type == input ) {
            device_mute(type, this_call->in_idx);
            self->chatwin->infobox.in_is_muted ^= 1;
        } else {
            device_mute(type, this_call->out_idx);
            self->chatwin->infobox.out_is_muted ^= 1;
        }

        pthread_mutex_unlock(&this_call->mutex);
    }

    return;

on_error:
    print_err (self, error_str);
}

void cmd_sense(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*argv)[MAX_STR_SIZE])
{
    const char *error_str;

    if ( argc != 1 ) {
        if ( argc < 1 ) error_str = "Must have value!";
        else error_str = "Only two arguments allowed!";

        goto on_error;
    }

    char *end;
    float value = strtof(argv[1], &end);

    if ( *end ) {
        error_str = "Invalid input";
        goto on_error;
    }

    /* Call must be active */
    if ( self->is_call ) {
        device_set_VAD_treshold(CallControl.calls[self->num].in_idx, value);
        self->chatwin->infobox.vad_lvl = value;
    }

    return;

on_error:
    print_err (self, error_str);
}

void cmd_bitrate(WINDOW *window, ToxWindow *self, Tox *m, int argc, char (*argv)[MAX_STR_SIZE])
{
    char *error_str;

    if ( argc != 1 ) {
        error_str = "Must have value!";
        goto on_error;
    }

    if ( self->is_call == false ) {
        error_str = "Must be in a call";
        goto on_error;
    }

    const uint32_t bitrate = strtol(argv[1], NULL, 10);

    TOXAV_ERR_BIT_RATE_SET error;
    audio_bit_rate_status_cb(CallControl.av, self->num, bitrate, &error);

    if (error != TOXAV_ERR_BIT_RATE_SET_OK) {
        switch (error) {
            case TOXAV_ERR_BIT_RATE_SET_SYNC:
                error_str = "Syncronization error occured";
                break;

            case TOXAV_ERR_BIT_RATE_SET_INVALID_BIT_RATE:
                error_str = "Invalid AV bit rate value (valid is 6-510)";
                break;

            case TOXAV_ERR_BIT_RATE_SET_FRIEND_NOT_FOUND:
                error_str = "Friend not found";
                break;

            case TOXAV_ERR_BIT_RATE_SET_FRIEND_NOT_IN_CALL:
                error_str = "Friend is not in the call";
                break;

            default:
                error_str = "Unknown error";
        }

        goto on_error;
    }

    return;

on_error:
    print_err (self, error_str);
}

void stop_current_call(ToxWindow *self)
{
    if ( CallControl.pending_call ) {
        toxav_call_control(CallControl.av, self->num, TOXAV_CALL_CONTROL_CANCEL, NULL);
        callback_call_canceled(self->num);
    } else {
        stop_transmission(&CallControl.calls[self->num], self->num);
        callback_call_ended(self->num);
    }

    CallControl.pending_call = false;
}

/**
 * Reallocates the Calls list according to n.
 */
static void realloc_calls(uint32_t n)
{
    if (n <= 0) {
        free(CallControl.calls);
        CallControl.calls = NULL;
        return;
    }

    Call *temp = realloc(CallControl.calls, n * sizeof(Call));

    if (temp == NULL) {
        exit_toxic_err("failed in realloc_calls", FATALERR_MEMORY);
    }

    CallControl.calls = temp;
}

/**
 * Inits the call structure for a given friend. Called when a friend is added to the friends list.
 * Index must be equivalent to the friend's friendlist index.
 */
void init_friend_AV(uint32_t index)
{
    realloc_calls(CallControl.max_calls + 1);
    memset(&CallControl.calls[CallControl.max_calls], 0, sizeof(Call));

    if (index == CallControl.max_calls) {
        ++CallControl.max_calls;
    }
}

/**
 * Deletes a call structure from the Calls list. Called when a friend is deleted from the friends list.
 * Index must be equivalent to the size of the Calls list.
 */
void del_friend_AV(uint32_t index)
{
    realloc_calls(index);
    CallControl.max_calls = index;
}