wallpaper

#!/bin/sh

# DESCRIPTION:
# * set image as a wallpaper
#
# ARGUMENTS:
# * image path
#
# DEPENDENCIES:
# * Interpreter: POSIX shell + coreutils
# * Wallpaper setter: xwallpaper | hsetroot | nitrogen | feh | Esetroot |
#     (xdpyinfo | xwininfo | xrdb) + (graphicsmagick | imagemagick)
#


set -o errexit  # exit on fail
set -o nounset  # exit on undeclared variable
# set -o xtrace   # trace execution


if [ -d "${1}" ]; then
    wp=$(shuf --echo --head-count=1 -- "${1}"/*)
else
    wp=${1}
fi


if command -v xwallpaper >/dev/null; then
    xwallpaper --stretch "${wp}"
    exit 0

elif command -v hsetroot >/dev/null; then
    hsetroot -fill "${wp}"
    exit 0

elif command -v nitrogen >/dev/null; then
    nitrogen --set-scaled -- "${wp}"
    exit 0

elif command -v feh >/dev/null; then
    feh --bg-scale --no-fehbg -- "${wp}"
    exit 0

elif command -v Esetroot >/dev/null; then
    Esetroot -scale "${wp}"
    exit 0

fi


if command -v xdpyinfo >/dev/null; then
    dimensions=$(
        xdpyinfo | grep dimensions |
        tr --squeeze-repeats ' ' | cut --delimiter=' ' --fields=3
    )

elif command -v xwininfo >/dev/null; then
    dimensions=$(
        xwininfo -root | grep geometry | tr '+' ' ' |
        tr --squeeze-repeats ' ' | cut --delimiter=' ' --fields=3
    )

elif command -v xrdb >/dev/null; then
    width=$(
        echo 'SKIP: WIDTH'| xrdb -n |
        tr '\t' ' ' | cut --delimiter=' ' --fields=2
    )
    height=$(
        echo 'SKIP: HEIGHT'| xrdb -n |
        tr '\t' ' ' | cut --delimiter=' ' --fields=2
    )
    dimensions=${width}x${height}

else
    echo "Could not get the screen geometry"
    exit 1

fi


if command -v gm >/dev/null; then
    gm display -geometry "${dimensions}!" -window root "${wp}"
    exit 0

elif command -v display >/dev/null; then
    display -resize "${dimensions}!" -window root -- "${wp}"
    exit 0

else
    # xloadimage/xsetbg and xli all suck bc they can't resize some files
    # xsetroot suck bc it can't set jpeg/png as a wallpaper
    echo "No appropriate wallpaper setter installed"
    exit 1

fi