#!/bin/sh -e

trap _restore_all 1 2 3 6

_list=${1:-/etc/unwind/blocklistproject.txt}
_url=https://blocklistproject.github.io/Lists/alt-version
_dir=/etc/unwind/lists

_restore_all() {
    echo "Signal received, aborting..."
    for _f in $_dir/*.old
    do
        echo "Restore: $(basename $_f)"
        doas mv -f "$_f" "${_f%%.old}"
    done
    _assemble
    _restart_unwind
    exit 1
}

_backup() {
    _f=$(basename "$1")
    if [ -f "$_dir/$_f" ]
    then
        echo "Backup: $_f -> $_f.old"
        doas mv -f "$_dir/$_f" "$_dir/$_f.old"
    fi
}

_restore() {
    _f=$(basename "$1")
    if [ -f "$_dir/$_f.old" ]
    then
        echo "Restore: $_f.old -> $_f"
        doas mv -f "$_dir/$_f" "$_dir/$_f.old"
    fi
}

_download() {
    echo "Download: $_file"
    doas ftp -V -o "$_dir/$_file" "$_url/$_file" > /dev/null \
        && doas rm -f "$_dir/$_file.old"
}
_disabled() {
    if echo "$1" | grep -q "^#"
    then
        _f=$(basename "$1" | tr -d '# ')
        echo "Skip (disabled): $_f"
        doas rm -f $_dir/$_f
        return 0
    fi
    return 1
}
_assemble() {
    echo "Assemble blocklist: /etc/unwind/_assembled.txt"
    cat $_dir/*.txt \
        | tr -d " " \
        | grep -v '^#' \
        | doas sort -uo /etc/unwind/_assembled.txt
}
_restart_unwind() {
    doas rcctl restart unwind
}

for _file in $(grep -v "^##" $_list | xargs)
do 
    if ! _disabled $_file
    then
        _backup $_file
        _download || _restore
    fi
done
_assemble
_restart_unwind