diff

#! /bin/bash -

# Returns the files that are unique among the dirs
if [[ "$1" == "-h" ]] || [[ "$1" == "--help" ]]; then
    >&2 printf "Usage: $0 <dir1> <dir2> ...\n"
    exit 0
fi

dir="$(dirname $(readlink -f ${BASH_SOURCE[0]}))"
export LC_ALL=C # byte-wise sorting
export GREP_COLOR='32'
export look="$dir/look"
export sorted_filehashes="$dir/sorted_file_hashes.out"

tempHashes=$(mktemp -p /dev/shm)
tempOut=$(mktemp -p /dev/shm)
trap "rm $tempHashes $tempOut" EXIT

getFileHashes()(
    path="$(readlink -f "$1")"
    path="${path//\\/\\\\}"
    path="${path//$'\n'/\\n}"
    escaped=$(printf '%s' "$path" | \
        sed -r 's/([\$\.\*\/\[\\^])/\\\1/g' | \
        sed 's/[]]/\[]]/g')
    replace=$(printf '%s' "$path" | \
        sed -r 's/(["&\/\\])/\\\1/g')
    modLine(){ sed "s|^$escaped|$replace/|g"; }
    tempFile=$(mktemp -p /dev/shm)
    trap "rm $tempFile" RETURN
    "$look" "$path/" "$sorted_filehashes" | \
        modLine > $tempFile
    if [[ $? -ne 0 || ! -s $tempFile ]]; then
        # fallback since look can not deal with special chars
        text='\e[33mWarning:\e[0m No matches -> using slower grep for %s\n'
        >&2 printf "$text" "$path"
        grep -aF "$path" "$sorted_filehashes" | \
        modLine > $tempFile
    fi
    if [[ ! -s $tempFile ]]; then
        >&2 printf '\e[33mWarning:\e[0m No entries found for %s\n' "$path"
    fi
    cat $tempFile
)
export -f getFileHashes

printf '%s\0' "$@" | parallel --will-cite -0 -k getFileHashes | tee $tempOut | \
    sed 's|^.*//||g' | sort | uniq -u > $tempHashes
ColorEsc=$(printf '\e[0m')
grep -aFf $tempHashes --color=always $tempOut | \
    sed "s|//|/|g; s/,[^,]*,[^,]*$/$ColorEsc/g"