#!/usr/bin/env bash

[ -z "$1" ] && echo "no out file supplied" && exit 1
out="$1"

base="$2"

# check if base was given
if [ ! -z $base ]; then
    # check if base exists
    [ ! -e $base ] && echo "invalid base" && exit 1
    # copy base to out
    cp $base $out
fi

# loop lists
for filename in ./lists/*.txt; do
    # line by line
    while read -r line; do
        # ignore empty
        [ -z "$line" ] && continue
        # ignore comments
        [[ $line =~ ^#.* ]] && continue

        # add to out
        echo "User-agent: $line" >> $out
        echo "Disallow: /" >> $out
    done < $filename
done