wallpaper changer

wl.sh

#!/bin/env bash

usage() {
    cat <<"EOF"
Usage:  wl [-R depth|-h] [dir]

-h          show this help
-R depth    Recursively search subdirectories with the specified depth.
            for example, a depth of 1 searches only files the current directory.
-s          shuffle images

Example:    wl -R 2 ~/backgrounds/

Keys:
j           go to the next image
k           go to the previous image
D           delete the current image
q           restore the original background and quit
w           quit (can also use ^C)

EOF
}

die() {
    echo "${0##*/}: $@" >&2
    exit 1
}

hash feh &>/dev/null || die "feh not found"

if [ -f "$HOME/.fehbg" ]
then
    current=$(cat ~/.fehbg | sed -n '/^feh*/p')
fi

# TODO: better detection for tiling wallpapers - image dimensions?
if [ ${PWD##*/} = "tile" ]
then
    arg="--bg-tile"
else
    arg="--bg-fill"
fi

depth=1
shuffle=0

while getopts ":R::sh" opt
do
    case $opt in
        R)
            depth=$OPTARG ;;
        s)
            shuffle=1 ;;
        h|\?)
            usage
            exit 1 ;;
    esac
done
shift $(( OPTIND - 1 ))

[ -n "$1" ] && dir="$@" || dir=$(pwd)

[ ! -d "$dir" ] && die "$@" is not an existing directory

IFS=$'\n'

files=( $(find "$dir" -maxdepth $depth -print -name '*' \
    -exec file '{}' -Nn -e apptype -e ascii -e encoding -e tokens -e cdf -e compress -e elf -e tar \; \
    | grep -oE '^[^:]*:\s\w*\simage' \
    | awk -F ':' '{print $1}') ) 2>/dev/null

[ -z $files ] && die "no images found"

if [ "$shuffle" -eq 1 ]; then
    shuffled=()
    checkArray () {
        for item in ${shuffled[@]}; do
            [[ "$item" == "$1" ]] && return 0
        done
        return 1
    }

    while [ "${#shuffled[@]}" -ne "${#files[@]}" ]; do
        rand=$[ $RANDOM % ${#files[@]} ]
        checkArray "${files[$rand]}" || shuffled=(${shuffled[@]} "${files[$rand]}")
    done

    files=(${shuffled[@]})
fi

echo "j = next; k = previous; D = delete; w = save; q = quit"

i=0
while true
do
    read -n1 -s key
    case $key in
        j)
            if [ $i -eq ${#files[@]} ]
            then
                i=1
            else
                (( i++ ))
            fi
            feh $arg ${files[$i-1]} 2>/dev/null
            echo "[$i/${#files[@]}] $(basename ${files[$i-1]})"
            ;;
        k)
            if [ $i -le 1 ]
            then
                i=${#files[@]}
            else
                (( i-- ))
            fi
            feh $arg ${files[$i-1]} 2>/dev/null
            echo "[$i/${#files[@]}] $(basename ${files[$i-1]})"
            ;;
        D)
            if [ $i -eq 0 ]
            then
                echo "${0##*/}: no active file to delete"
            else
                rm ${files[$i-1]}
                echo -e "\e[1;31m[$i/${#files[@]}] ${files[$i-1]} deleted\e[0m"
                del=${files[$i-1]}
                files=(${files[@]#$del})
                feh $arg ${files[$i-1]}
                echo "[$i/${#files[@]}] $(basename ${files[$i-1]})"
            fi
            ;;
        q)
            [ -n $current ] && eval $current 2>/dev/null
            exit 0
            ;;
        w)
            exit 0
            ;;
    esac
done
unset IFS