#!/bin/sh
#
# Remove old incremtal inc of all jails
# Usage: rm
#

# shellcheck source=./includes
LIBDIR="$(dirname $0)" && . "${LIBDIR}/includes"

relative_date() {
    format=$(echo $1 | cut -d'.' -f1)
    time_jump=$(echo $1 | cut -d'.' -f2)

    reference_date=$(date "${format}")
    past_date=$(date --date "${reference_date} ${time_jump}" +"%Y-%m-%d")

    echo ${past_date}
}

delete_inc_btrfs() {
    jail_name=$1
    inc_name=$2

    inc_path=$(inc_path "${jail_name}" "${inc_name}")

    start=$(current_time)

    if dry_run; then
        echo "[dry-run] delete btrfs subvolume ${inc_path}"
    else
        /bin/btrfs subvolume delete "${inc_path}" | debug
    fi

    end=$(current_time)
    notice "${jail_name}: inc '${inc_name}' has been deleted [${start}/${end}]"
}
delete_inc_ext4() {
    jail_name=$1
    inc_name=$2

    inc_path=$(inc_path "${jail_name}" "${inc_name}")

    lock_file="${LOCKDIR}/rm-global.lock"
    if [ -f "${lock_file}" ]; then
        # Get Process ID from the lock file
        pid=$(cat "${lock_file}")
        if kill -0 ${pid} 2> /dev/null; then
            # Kill the children
            pkill -9 --parent "${pid}"
            # Kill the parent
            kill -9 "${pid}"
            # Remove the lock file
            rm -f ${lock_file}
            warning "Process ${pid} has been killed. Only one ${0} can run in parallel, the latest wins."
        else
            error "Empty lockfile '${lock_file}'. It should contain a PID."
        fi
    fi

    mkdir --parents "${LOCKDIR}" && echo $$ > ${lock_file} || error "Failed to acquire lock file '${lock_file}'"
    empty=$(mktemp -d --suffix ".${$}" bkctld.XXXXX)
    # shellcheck disable=SC2064
    trap "rm -f ${lock_file}; rmdir ${empty}" 0

    if dry_run; then
        echo "[dry-run] delete ${inc_path} with rsync from ${empty}"
    else
        rsync --archive --delete "${empty}/" "${inc_path}/"
        rmdir "${inc_path}/"
    fi

    end=$(current_time)
    notice "${jail_name}: inc '${inc_name}' has been deleted [${start}/${end}]"
}

for jail_name in $(jails_list); do
    incs_policy_file=$(current_jail_incs_policy_file ${jail_name})

    # If not incs policy if found, we don't remove incs
    if [ -n "${incs_policy_file}" ]; then
        incs_policy_keep_file="$(mktemp)"
        incs_list_file="$(mktemp)"
        # shellcheck disable=SC2064
        trap "rm -f ${incs_policy_keep_file} ${incs_list_file}" 0

        # loop for each line in jail configuration
        for incs_policy_line in $(grep "^\+" ${incs_policy_file}); do
            # inc date in ISO format
            incs_policy_date=$(relative_date ${incs_policy_line})
            echo ${incs_policy_date} >> "${incs_policy_keep_file}"
        done
        for inc_name in $(incs_list "${jail_name}"); do
            echo "${inc_name}" >> ${incs_list_file}
        done
        # shellcheck disable=SC2046
        incs_to_delete=$(grep -v -f "${incs_policy_keep_file}" "${incs_list_file}")

        if [ -n "${incs_to_delete}" ]; then
            debug "${jail_name}: incs to be deleted : $(echo "${incs_to_delete}" | tr '\n', ',' | sed 's/,$//')."
            for inc_name in ${incs_to_delete}; do
                inc_path=$(inc_path "${jail_name}" "${inc_name}")
                if is_btrfs "${inc_path}"; then
                    delete_inc_btrfs "${jail_name}" "${inc_name}"
                else
                    delete_inc_ext4 "${jail_name}" "${inc_name}"
                fi
            done
        else
            notice "${jail_name}: no inc to be deleted."
        fi
    fi
done