import { by_character, by_lurid } from 'jsr:@andyburke/fsdb/organizers';
import { FSDB_COLLECTION } from 'jsr:@andyburke/fsdb';
import { FSDB_INDEXER_SYMLINKS } from 'jsr:@andyburke/fsdb/indexers';

/**
 * @typedef {object} TIMESTAMPS
 * @property {string} created		when the event was created
 * @property {string} updated		when the event was last updated
 */

/**
 * Event
 *
 * @property {string} id					- lurid
 * @property {string} creator_id			- id of the source user
 * @property {string} room_id				- id of the target room
 * @property {string} type					- event type
 * @property {string[]} [tags]				- optional event tags
 * @property {Record<string,any>} [data]	- optional data payload of the event
 * @property {TIMESTAMPS} timestamps		- timestamps that will be set by the server
 */
export type EVENT = {
	id: string;
	creator_id: string;
	type: string;
	tags?: string[];
	data?: Record<string, any>;
	timestamps: {
		created: string;
		updated: string;
	};
};

type ROOM_EVENT_CACHE_ENTRY = {
	collection: FSDB_COLLECTION<EVENT>;
	eviction_timeout: number;
};

const ROOM_EVENTS: Record<string, ROOM_EVENT_CACHE_ENTRY> = {};
export function get_events_collection_for_room(room_id: string): FSDB_COLLECTION<EVENT> {
	ROOM_EVENTS[room_id] = ROOM_EVENTS[room_id] ?? {
		collection: new FSDB_COLLECTION<EVENT>({
			name: `rooms/${room_id.slice(0, 14)}/${room_id.slice(0, 34)}/${room_id}/events`,
			id_field: 'id',
			organize: by_lurid,
			indexers: {
				creator_id: new FSDB_INDEXER_SYMLINKS<EVENT>({
					name: 'creator_id',
					field: 'creator_id',
					to_many: true,
					organize: by_lurid
				}),

				tags: new FSDB_INDEXER_SYMLINKS<EVENT>({
					name: 'tags',
					get_values_to_index: (event: EVENT): string[] => {
						return (event.tags ?? []).map((tag: string) => tag.toLowerCase());
					},
					to_many: true,
					organize: by_character
				})
			}
		}),
		eviction_timeout: 0
	};

	if (ROOM_EVENTS[room_id].eviction_timeout) {
		clearTimeout(ROOM_EVENTS[room_id].eviction_timeout);
	}

	ROOM_EVENTS[room_id].eviction_timeout = setTimeout(() => {
		delete ROOM_EVENTS[room_id];
	}, 60_000 * 5);

	return ROOM_EVENTS[room_id].collection;
}

export function clear_room_events_cache() {
	for (const [room_id, cached] of Object.entries(ROOM_EVENTS)) {
		if (cached.eviction_timeout) {
			clearTimeout(cached.eviction_timeout);
		}
		delete ROOM_EVENTS[room_id];
	}
}