#!/usr/bin/env bash

if [ $# != 1 ]; then
    echo "Usage: ${0} up|down"
    exit 1
fi

STEP=5

get_vol() {
    mpc --host=/home/user/.config/mpd/socket volume
}

set_vol() {
    mpc --host=/home/user/.config/mpd/socket volume "$1"
}

case "$1" in
    up)
        set_vol +$((STEP))
        ;;
    down)
        set_vol -$((STEP))
        ;;
    *)
        echo "Usage: ${0} up|down"
        exit 1
        ;;
esac