#!/bin/bash
set -euo pipefail

clear-apt-snaps () {
    zfs list -t snapshot | grep 'apt-' | sed 's| .*$||g' | head -n -5 | xargs -d '\n' -I {} sudo zfs destroy {}
}

if [ -z "$1" ]; then
    exit 1
fi
    
if ! [ -z "$1" ] && [ "$1" == "upgrades" ]; then
    while getopts "r:" opt; do
        case "$opt" in
            r) REGEX=${OPTARG};;
            *) exit 1;;
        esac
    done

    if [ -z "$REGEX" ]; then
        clear-apt-snaps
    else
        zfs list -t snapshot | grep "${REGEX}" | sed 's| .*$||g' | head -n -5 | xargs -d '\n' -I {} sudo zfs destroy {}
    fi
fi