#!/usr/bin/env bash

#
# xrbg(1) -- Apply a random background image.
#
# Author: Tom Ryder <tom@sanctum.geek.nz>
# Copyright: 2016
# License: Public domain
#
self=xrbg

# Path to the backgrounds directory
bgd=${XBACKGROUNDS:-$HOME/.xbackgrounds}

# Collect all the background images in an array if they
# match some kosher extensions
shopt -s nullglob
declare -a bgs
bgs=("$bgd"/*)

# If there are no images, warn explicitly and bail
if ! ((${#bgs[@]})) ; then
    printf '%s: No background images found in %s\n' \
        "$self" "$bgd"
    exit 1
fi

# Pick one of the images (note shuf(1) needed)
rbg=$(shuf -en1 "${bgs[@]}") || exit 1

# Apply it as the background and we're done
feh --bg-scale --no-fehbg -- "$rbg"