#!/bin/bash

set -eu -o pipefail

readonly script_dir="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
readonly task_worker="${script_dir}/../taskworker.js"

if [[ ${EUID} -ne 0 ]]; then
    echo "This script should be run as root." > /dev/stderr
    exit 1
fi

if [[ $# -eq 0 ]]; then
    echo "No arguments supplied"
    exit 1
fi

if [[ "$1" == "--check" ]]; then
    echo "OK"
    exit 0
fi

readonly task_id="$1"
readonly logfile="$2"
readonly nice="$3"
readonly memory_limit_mb="$4" # SI units
readonly oom_score_adjust="$5"

readonly service_name="box-task-${task_id}"
systemctl reset-failed "${service_name}" 2>/dev/null || true

readonly id=$(id -u $SUDO_USER)

options="-p TimeoutStopSec=10s -p MemoryMax=${memory_limit_mb}M -p OOMScoreAdjust=${oom_score_adjust} --wait"

# Note: BindsTo will kill this task when the box is stopped. but will not kill this task when restarted!
# For this reason, we have code to kill the tasks both on shutdown and startup.
[[ "$BOX_ENV" == "cloudron" ]] && options="${options} -p BindsTo=box.service"

# DEBUG has to be hardcoded because it is not set in the tests. --setenv is required for ubuntu 16 (-E does not work)
# it seems systemd-run does not return the exit status of the process despite --wait
if ! systemd-run --unit "${service_name}" --nice "${nice}" --uid=${id} --gid=${id} ${options} --setenv HOME=${HOME} --setenv USER=${SUDO_USER} --setenv DEBUG=box:* --setenv BOX_ENV=${BOX_ENV} --setenv NODE_ENV=production "${task_worker}" "${task_id}" "${logfile}"; then
    echo "Service ${service_name} failed to run" # this only happens if the path to task worker itself is wrong
fi

exit_code=$(systemctl show "${service_name}" -p ExecMainCode | sed 's/ExecMainCode=//g')

echo "Service ${service_name} finished with exit code ${exit_code}"
exit "${exit_code}"