#!/bin/sh /etc/rc.common
# Copyright (C) 2022 jjm2473@gmail.com

USE_PROCD=1
START=49

extra_command "task_add" "<task_id> <task_cmd> [<time_wait>] Add and run a task, time_wait is wait time before auto delete stopped task, in seconds, -1 means forever"
extra_command "task_del" "<task_id> Stop and delete task"
extra_command "task_status" "[<task_id>] Dump task status, dump all tasks if no task_id specified"
extra_command "task_gc" "Auto delete exipred (stopped and after timw_wait) tasks"
extra_command "_task_onstop" "<task_id> Update stop time, for internal usage"

_task_add() {
	local task_id="${1}"
	local task_cmd="${2}"
	local time_wait="${3}"
	> "/var/log/tasks/$task_id.log"
	procd_open_instance "$task_id"
	procd_set_param data start=`date +'%s'` time_wait="$time_wait"
	procd_set_param command sh -c "exec /usr/libexec/taskd '$task_id' \"\$0\"" "$task_cmd"
	procd_set_param stderr 1
	procd_close_instance
}

task_add() {
	local task_id="${1}"
	local task_cmd="${2}"
	local time_wait="${3}"
	[ -z "$task_id" -o -z "$task_cmd" ] && return 127

	if service_running "$task_id"; then
		echo "already running" >&2
		return 1
	fi
	if ! mkdir -p /var/log/tasks; then
		echo "create /var/log/tasks failed!" >&2
		return 1
	fi
	rc_procd _task_add "$task_id" "$task_cmd" "$time_wait"
	return 0
}

_task_del() {
	local service="${1}"
	local task_id="${2}"
	procd_kill "$service" "$task_id"
	> "/var/log/tasks/$task_id.log"
	rm -f "/var/log/tasks/$task_id.log"
}

task_del() {
	local task_id="${1}"
	[ -z "$task_id" ] && return 127
	procd_lock
	_task_del "$(basename ${basescript:-$initscript})" "$task_id"
	if [ "$(_task_status "$task_id" | jsonfilter -e '$.running' 2>/dev/null)" = "true" ]; then
		return 1
	else
		return 0
	fi
}

_task_status() {
	local service="$(basename ${basescript:-$initscript})"
	local instance="$1"
	local data

	json_init
	json_add_string name "$service"

	data=$(_procd_ubus_call list | jsonfilter -e '@["'"$service"'"]')
	[ -z "$data" ] && return 1

	data=$(echo "$data" | jsonfilter -e '$.instances')
	if [ -z "$data" ]; then
		if [ -z "$instance" ]; then
			echo "{}"
			return 0
		fi
		return 1
	fi

	if [ -z "$instance" ]; then
		echo "$data"
	else
		instance="\"$instance\""
		echo "$data" | jsonfilter -e '$['"$instance"']'
	fi
	return 0
}

task_status() {
	local task_id="${1}"
	_task_status "$task_id"
}

task_gc() {
	local service="$(basename ${basescript:-$initscript})"
	local task_id instance time_wait
	local data

	json_init
	[ -n "$service" ] && json_add_string name "$service"

	data=$(_procd_ubus_call list | jsonfilter -e '@["'"$service"'"]')
	[ -z "$data" ] && return 1

	data=$(echo "$data" | jsonfilter -e '$.instances')
	[ -z "$data" ] && return 1

	procd_lock

	ls /var/log/tasks/ | sed 's/.log$//g' | while read task_id; do
		instance=$(echo "$data" | jsonfilter -e '$["'"$task_id"'"]')
		[ "$(echo "$instance" | jsonfilter -e '$.running')" = "false" ] || continue
		time_wait=$(echo "$instance" | jsonfilter -e '$.data.time_wait')
		[ "$time_wait" = "-1" ] && continue
		[ $(($(date +'%s' -r "/var/log/tasks/$task_id.log") + ${time_wait:-0})) -lt `date +'%s'` ] && _task_del "$service" "$task_id"
	done
}

_insert_exit() {
	local exit_code="$2"
	eval "`jshn -r "$1" | grep -v json_init`"
	json_select data || {
		_procd_set_param data stop=`date +'%s'` exit_code="$exit_code"
		return
	}
	json_add_string stop `date +'%s'`
	json_add_string exit_code "$exit_code"
	json_select ..
}

_task_exit() {
	local task_id="$1"
	local exit_code="$2"
	local inst_json="$3"

	_procd_call json_add_object "$task_id"
	_procd_call _insert_exit "$inst_json" "$exit_code"
	_procd_call json_close_object
}

_task_onstop() {
	local task_id="${1}"
	local exit_code="${2}"
	[ -z "$task_id" ] && return 127
	local service="$(basename ${basescript:-$initscript})"

	json_init
	json_add_string name "$service"
	data=$(_procd_ubus_call list | jsonfilter -e '@["'"$service"'"].instances["'"$task_id"'"]')
	[ -z "$data" ] && return 1
	json_cleanup

	rc_procd _task_exit "$task_id" "$exit_code" "$data"
}