#!/bin/sh

set -e

before_install() {
   :
}

before_upgrade() {
    :
}

if [ "${1}" = "install" -a -z "${2}" ]
then
    before_install
elif [ "${1}" = "upgrade" -a -n "${2}" ]
then
    upgradeFromVersion="${2}"
    before_upgrade "${upgradeFromVersion}"
elif [ "${1}" = "install" -a -n "${2}" ]
then
    upgradeFromVersion="${2}"
    # Executed when a package is removed but its config files aren't,
    # and a new version is installed.
    # Looks a _lot_ like an upgrade case, I say we just execute the
    # same "before upgrade" script as in the previous case
    before_upgrade "${upgradeFromVersion}"
elif echo "${1}" | grep -E -q '(fail|abort)'
then
    echo "Failed to install before the pre-installation script was run." >&2
    exit 1
fi