namespace _zeitbild.api
{
	
	/**
	 */
	export function register_caldav_get(
		rest_subject : lib_plankton.rest_caldav.type_rest
	) : void
	{
		register<
			null,
			(
				null
				|
				string
				|
				lib_plankton.ical.type_vcalendar
			)
		>(
			rest_subject,
			lib_plankton.caldav.enum_method.report,
			"/caldav/project/:id",
			{
				"description": "trägt Veranstaltungen aus verschiedenen Kalendern zusammen im ical-Format",
				"query_parameters": () => ([
					{
						"name": "from",
						"required": false,
						"description": "UNIX timestamp",
					},
					{
						"name": "to",
						"required": false,
						"description": "UNIX timestamp",
					},
					{
						"name": "calendar_ids",
						"required": false,
						"description": "comma separated",
					},
					{
						"name": "auth",
						"required": true,
						"description": "",
					},
				]),
				"output_schema": () => ({
					"nullable": false,
					"type": "string",
				}),
				"response_body_mimetype": "text/calendar",
				"response_body_encode": (output) => (
					(output === null)
					?
					null
					:
					Buffer.from(
						(typeof(output) === "string")
						?
						output
						:
						lib_plankton.ical.ics_encode(output)
					)
				),
				"restriction": restriction_none,
				/**
				 * @todo use stuff.path_parameters["id"]
				 */
				"execution": async (stuff) => {
					const user_id : (null | type_user_id) = await _zeitbild.api.web_auth(
						stuff.headers["Authorization"]
						??
						stuff.headers["authorization"]
						??
						null
					);
					if (user_id === null) {
						return Promise.resolve(
							{
								"status_code": 401,
								"data": null,
								"extra_headers": {
									"WWW-Authenticate": "Basic realm=Restricted",
								}
							}
						);
					}
					else {
						const from : lib_plankton.pit.type_pit = (
							("from" in stuff.query_parameters)
							?
							parseInt(stuff.query_parameters["from"])
							:
							lib_plankton.pit.shift_week(
								lib_plankton.pit.now(),
								-2
							)
						);
						const to : lib_plankton.pit.type_pit = (
							("to" in stuff.query_parameters)
							?
							parseInt(stuff.query_parameters["to"])
							:
							lib_plankton.pit.shift_week(
								lib_plankton.pit.now(),
								+6
							)
						);
						const calendar_ids_wanted : (null | Array<_zeitbild.type_calendar_id>) = (
							(
								("calendar_ids" in stuff.query_parameters)
								&&
								(stuff.query_parameters["calendar_ids"] !== null)
							)
							?
							lib_plankton.call.convey(
								stuff.query_parameters["calendar_ids"],
								[
									(x : string) => x.split(","),
									(x : Array<string>) => x.map(parseInt),
									(x : Array<int>) => x.filter(y => (! isNaN(y)))
								]
							)
							:
							null
						);
						
						return (
							_zeitbild.service.calendar.gather_events(
								calendar_ids_wanted,
								from,
								to,
								user_id
							)
							.then(
								(data) => Promise.resolve(
									{
										"status_code": 200,
										"data": _zeitbild.helpers.ical_vcalendar_from_own_event_list(
											data.map(entry => entry.event_object)
										)
									}
								)
							)
							.catch(
								(reason) => Promise.resolve(
									{
										"status_code": 403,
										"data": String(reason),
									}
								)
							)
						);
					}
				}
			}
		);
	}
	
}