#!/bin/sh
# SPDX-License-Identifier: AGPL-3.0-only
# Copyright 2022 Sxmo Contributors

# include common definitions
# shellcheck source=scripts/core/sxmo_common.sh
. sxmo_common.sh

ROOT="$XDG_RUNTIME_DIR/sxmo_jobs"
mkdir -p "$ROOT"

exec 3<> "$XDG_RUNTIME_DIR/sxmo.jobs.lock"
flock -x 3

list() {
	for f in "$ROOT"/*; do
		[ -e "$f" ] || continue
		case "$f" in
			*.group) continue ;;
		esac
		printf "%s\n" "${f##*/}"
	done
}

stop() {
	while [ "$#" -gt 0 ]; do
		case "$1" in
			-f)
				force=1
				shift
				;;
			*)
				id="$1"
				shift
				break
				;;
		esac
	done

	case "$id" in
		all)
			list | while read -r sub_id; do
				stop "$sub_id"
			done
			;;
		*)
			if [ -f "$ROOT/$id.group" ]; then
				sxmo_debug "stop group $id"
				read -r pid < "$ROOT/$id.group" 2>/dev/null || pid=""
				[ -n "$pid" ] && kill ${force:+-9} -- "-$pid" 2> /dev/null || true
			elif [ -f "$ROOT/$id" ]; then
				sxmo_debug "stop $id"
				read -r pid < "$ROOT/$id" 2>/dev/null || pid=""
				[ -n "$pid" ] && kill ${force:+-9} "$pid" 2> /dev/null || true
			fi

			rm -f "$ROOT/$id" "$ROOT/$id.group" 2>/dev/null || true
			;;
	esac
}

signal() {
	id="$1"
	shift

	if [ -f "$ROOT/$id" ]; then
		sxmo_debug "signal $id $*"
		read -r pid < "$ROOT/$id" 2>/dev/null || pid=""
		[ -n "$pid" ] && kill "$@" "$pid" 2> /dev/null || true
	fi
}

start() {
	while [ "$#" -gt 0 ]; do
		case "$1" in
			--no-restart)
				no_restart=1
				shift
				;;
			--group)
				has_group=1
				shift
				;;
			*)
				id="$1"
				shift
				break
				;;
		esac
	done

	if [ -f "$ROOT/$id" ]; then
		if [ -n "$no_restart" ]; then
			sxmo_debug "$id already running"
			exit 1
		else
			stop "$id"
		fi
	fi

	sxmo_debug "start $id"
	# Start job in a new session, close the lock fd, and record PID synchronously
	# before releasing the jobs lock so subsequent stop calls never race.
	setsid "$@" 3<&- &
	job_pid=$!
	printf "%s\n" "$job_pid" > "$ROOT/$id"
	if [ -n "$has_group" ]; then
		printf "%s\n" "$job_pid" > "$ROOT/$id.group"
	fi
}

running() {
	while [ "$#" -gt 0 ]; do
		case "$1" in
			-q)
				quiet=1
				shift
				;;
			*)
				id="$1"
				shift
				;;
		esac
	done

	log() {
		if [ -z "$quiet" ]; then
			# shellcheck disable=SC2059
			printf "$@"
		fi
	}

	if [ -f "$ROOT/$id" ]; then
		read -r pid < "$ROOT/$id" 2>/dev/null || pid=""
		if [ -n "$pid" ] && [ -d "/proc/$pid" ]; then
			log "%s is still running\n" "$id"
		else
			log "%s is not running anymore\n" "$id"
			exit 2
		fi
	else
		log "%s is not running\n" "$id"
		exit 1
	fi
}

"$@"