<?php
	/**
	 * \file
	 * Implement Community listings for the [Listing Provider API](https://codeberg.org/gravel/session-listing-providers).
	 */

	require_once "getenv.php";
	require_once "utils/logging.php";
	require_once "servers/servers-rooms.php";

	/**
	 * Represents a Community listing in the Listing Provider API.
	 */
	class CommunityListing implements JsonSerializable {
		/**
		 * @var string $id
		 * Unique listing identifier.
		 */
		public readonly string $id;
		/**
		 * @var string $name
		 * Human-readable listing name.
		 */
		public readonly string $name;
		/**
		 * @var string $rating
		 * One-word content rating for Communities listed.
		 */
		public readonly string $rating;
		/**
		 * @var CommunityRoom[] $rooms
		 * Communities included in the listing.
		 */
		public readonly array $rooms;

		/**
		 * Create a new CommunityListing instance with the given parameters.
		 * @param string $id Unique listing identifier.
		 * @param string $name Human-readable listing name.
		 * @param string $rating One-word content rating for Communities listed.
		 * @param CommunityRoom[] $rooms Communities included in the listing.
		 */
		public function __construct(string $id, string $name, ?string $rating, array $rooms) {
			$this->id = $id;
			$this->name = $name;
			$this->rating = $rating ?? "unknown";
			$this->rooms = $rooms;
		}

		/**
		 * Produce associative listing data for JSON serialization.
		 */
		public function jsonSerialize(): mixed {
			// TODO: Careful serialization
			$details = get_object_vars($this);
			$details['rooms'] = array_map(function(CommunityRoom $room){
				return $room->to_listing_data();
			}, $this->rooms);
			return $details;
		}

		/**
		 * Produce associative data summarizing this listing.
		 */
		public function to_summary(): array {
			return array(
				'id' => $this->id,
				'name' => $this->name,
				'rating' => $this->rating,
				'rooms' => count($this->rooms)
			);
		}
	}

	/**
	 * Construct Community listings from listing configuration and cached Communities.
	 * @return CommunityListing[]
	 * \todo Refactor
	 */
	function resolve_listings_config(): array {
		global $LISTINGS_INI, $ROOMS_FILE;

		$listings_raw = parse_ini_file($LISTINGS_INI, process_sections: true, scanner_mode: INI_SCANNER_RAW);
		$servers_raw = file_get_contents($ROOMS_FILE);
		$server_data = json_decode($servers_raw, true);

		$servers = CommunityServer::from_details_array($server_data);
		$rooms_all = CommunityServer::enumerate_rooms($servers);

		$listings = [];
		foreach ($listings_raw as $id => $listing_props) {
			$filter = [...($listing_props['rooms'] ?? []), ...($listing_props['sogs'] ?? [])];
			$matchees = [];
			$rooms = CommunityRoom::select_rooms($rooms_all, $filter, $matchees);

			foreach ($filter as $filter_item) {
				if (!in_array($filter_item, $matchees)) {
					log_warning("Could not find $filter_item from listing $id.");
				}
			}

			$rooms = array_filter($rooms, function(CommunityRoom $room) {
				return !$room->is_off_record();
			});

			$listings[] = new CommunityListing(
				$id,
				$listing_props['name'],
				$listing_props['rating'],
				$rooms
			);
		}

		return $listings;
	}

	/**
	 * Resolve and write configured Community listings to disk.
	 */
	function generate_listings() {
		global $LISTING_PROVIDER_LISTING_SUMMARY, $LISTING_PROVIDER_LISTINGS;
		log_info("Generating listings...");

		$listings_resolved = resolve_listings_config();
		$summaries = array_map(function(CommunityListing $listing) {
			return $listing->to_summary();
		}, $listings_resolved);
		file_put_contents($LISTING_PROVIDER_LISTING_SUMMARY, json_encode($summaries));
		foreach ($listings_resolved as $listing) {
			$id = $listing->id;
			file_put_contents(
				"$LISTING_PROVIDER_LISTINGS/$id",
				json_encode($listing)
			);
		}
		$listings_count = count($listings_resolved);
		log_info("Generated $listings_count listings.");
	}

	file_exists($LISTING_PROVIDER_LISTINGS) or mkdir($LISTING_PROVIDER_LISTINGS, 0755, true);

	$options = getopt("v", ["verbose"]);
	if (isset($options["v"]) or isset($options["verbose"])) {
		$LOGGING_VERBOSITY = LoggingVerbosity::Debug;
	}

	generate_listings();
?>