#!/bin/bash

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

STEP=0.03  # Volume change step

get_vol() {
    playerctl -p mpd volume
}

set_vol() {
    playerctl -p mpd volume $1
}

current_vol=$(get_vol)

case $1 in
    up)
        new_vol=$(echo "$current_vol + $STEP" | bc)
        [[ $(echo "$new_vol > 1.0" | bc) -eq 1 ]] && new_vol=1.0
        set_vol $new_vol
        ;;
    down)
        new_vol=$(echo "$current_vol - $STEP" | bc)
        [[ $(echo "$new_vol < 0.0" | bc) -eq 1 ]] && new_vol=0.0
        set_vol $new_vol
        ;;
    mute)
        if [[ "$current_vol" != "0.0" ]]; then
            set_vol 0.0
        else
            set_vol 0.5  # or store last volume
        fi
        ;;
    *)
        echo "Usage: ${0} up|down|mute"
        ;;
esac