mpvc-autostart

#!/usr/bin/env sh
#
# @file mpvc-autostart
# @description mpvc auto pause/resume audio based on device presence
# @author gmt4 <gmt4 at github.com> (c) Copyright 2022 GPLv2+
# @url github.com/gmt4/mpvc
# SPDX-License-Identifier: GPL-2.0-or-later
#

PROGNAME=${0##*/}
PROGVERSION="v1.6"
PROGAUTHOR=gmt4
PROGURL="https://github.com/gmt4/mpvc"

set -euf

mpvc_defaults()
{
    ARGS=${ARGS:-}
}

mpvc_pingcheck() { ping -c 5 "$@" | awk 'NR == 2 && /time=/ { sub(":.*time=",": time="); print }'; }
mpvc_btcheck()   { hcitool scan | awk "/$@/ {print}"; }

# monitor presence of your phone (eg LAN IP/BT): if device is present resume audio, otherwise, pause audio.
mpvc_autoscan()
{
    target="$1"
    CHECK=${CHECK:-mpvc_pingcheck}
    PERIOD=${PERIOD:-300}
    NCHECK=${NCHECK:-3}
    MPVC_HOURMIN=${MPVC_HOURMIN:-6}
    MPVC_HOURMAX=${MPVC_HOURMAX:-20}
    ncheck=0

    echo "# $PROGNAME $@ CHECK=$CHECK PERIOD=$PERIOD NCHECK=$NCHECK"
    while sleep ${PERIOD}
    do
        hour=$(date +%_H)
        pause=$(mpvc -q get pause || true)
        check=$($CHECK $target)
        nsign=$(if [ -n "$check" ]; then echo +; else echo -; fi)
        ncheck=$(( ( $ncheck $nsign 1 ) % ( $NCHECK + 1 ) ))
        if [ "$hour" -ge ${MPVC_HOURMIN} -a "$hour" -lt ${MPVC_HOURMAX} ]
        then
            if [ "$ncheck" -gt 0 ]; then mpvc -q resume || true; fi       # n>0 pings up: resume
            if [ "$ncheck" -le -$NCHECK ]; then mpvc -q pause || true; fi # n<0 pings down: pause
        fi
        echo "# $(date) PERIOD=$PERIOD NCHECK=$NCHECK pause=$pause c=${#check} n=${ncheck} $check" # $@
    done
}

optflags="hi:n:p:m:M:"
usage()
{
    cat <<EOF
usage: $PROGNAME -[$optflags] args # @version $PROGVERSION (c) $PROGAUTHOR $PROGURL
 -i : The IP of the device to detect ping presence for $PROGNAME (*required)
 -p : The number of seconds between ping presence checks
 -n : The number of failed ping presence checks after which to pause mpvc
 -m : The minimum hour when to start ping presence (for example morning: 7 AM)
 -M : The maximum hour when to stop ping presence (for example night: 20 PM)
*tips: If unsure where to begin, run: $PROGNAME -i 192.168.0.2 # your tablet/phone LAN IP
EOF
    exit;
}

main()
{
    [ $# -lt 1 ] && usage

    mpvc_defaults
    while getopts "$optflags" flag;
    do
        case "$flag" in
        h) usage ;;
        i) ARGS="$ARGS $OPTARG"; ;;
        p) PERIOD="$OPTARG"; ;;
        n) NCHECK="$OPTARG"; ;;
        m) MPVC_HOURMIN="$OPTARG" ;;
        M) MPVC_HOURMAX="$OPTARG" ;;
        *) usage ;;
        esac
    done
    shift $((OPTIND - 1))

    [ -z "${ARGS:-}" ] && usage "Error: No -i option provided (required)"
    mpvc_autoscan "$ARGS"
}

main "$@"