screenshot

#!/bin/sh -e
# shellcheck disable=SC2046

firstArg="$1"
shift
case "$firstArg" in

    -g)
        IFS=:+ read -r WIDTH HEIGHT X Y
        ;;
    -a)
        X=$1
        Y=$2
        WIDTH=$3
        HEIGHT=$4
        shift 4
        ;;
    -e)
        ;;
    -s)
        exec $0 -a $(xrectsel "%x %y %w %h") "$@"
        ;;
    -i)
        exec env $(xdotool getwindowgeometry --shell "$(xdotool selectwindow)") "$0" -e "$@"
        ;;
    -f)
        exec env $(xdotool getwindowgeometry --shell "$(xdotool getwindowfocus)") "$0" -e "$@"
        ;;
    -w)
        window=$1
        shift
        exec env $(xdotool getwindowgeometry --shell "$window") "$0" -e "$@"
esac

if [ "$WIDTH" -eq 0 ] || [ "$HEIGHT" -eq 0 ] ; then
    exit 1
fi
echo "$WIDTH:$HEIGHT:$X:$Y" >&2

defaultExt=png
take_video=0
if [ "$(basename "$0")" = screencast ] || [ "$2" = screencast ]; then
    defaultExt=mp4
    take_video=1
elif [ "$(basename "$0")" = screencastaudio ] || [ "$2" = screencastaudio ]; then
    defaultExt=mp4
    take_video=2
elif [ "$(basename "$0")" = screenrecord ] || [ "$2" = screenrecord ]; then
    defaultExt=mp4
    take_video=2
    ALSA_INPUT_DEVICE=${ALSA_INPUT_DEVICE:-hw:Loopback,0,0}
fi

[ -n "$1" ] && fileName=$1 || fileName="$(date -u +%F_%H:%M:%S)_$$.$defaultExt"
if [ "$fileName" = "?" ]; then
    cd "${PICTURES_DIR:-~}"
    fileName=$(dmenu -p 'Enter file name' </dev/null)
fi
[ -d "$fileName" ] && fileName="$fileName/$(date -u +%s)_$$.$defaultExt"

if [ "$take_video" -eq 0 ]; then
    ffmpeg -video_size "$WIDTH"x"$HEIGHT" -f x11grab -i ":0.0+$X,$Y" -vframes 1 "$fileName"
elif [ "$take_video" -eq 1 ]; then
    ffmpeg -video_size "$WIDTH"x"$HEIGHT" -framerate 25 -f x11grab -i ":0.0+$X,$Y" "$fileName"

elif [ "$take_video" -eq 2 ]; then
    echo "$ALSA_INPUT_DEVICE"
    ffmpeg -video_size "$WIDTH"x"$HEIGHT" -framerate 25 -f x11grab -i ":0.0+$X,$Y" -f alsa -ac 2 -i "${ALSA_INPUT_DEVICE:-hw:0}" "$fileName"
fi

echo "$fileName"