<?php
/**
 * Admin dashboard statistics endpoint.
 *
 * @package SpaceBay
 */

namespace SpaceBay\Rest;

use SpaceBay\Database\Tables;
use WP_REST_Request;
use WP_REST_Response;
use WP_REST_Server;

defined( 'ABSPATH' ) || exit;

/**
 * Returns community totals for the admin dashboard.
 */
final class StatsController extends Controller {

	/**
	 * Transient that caches the totals.
	 *
	 * @var string
	 */
	const CACHE_KEY = 'spacebay_admin_stats';

	/**
	 * Registers the /admin/stats route.
	 *
	 * @return void
	 */
	public function register_routes() {
		register_rest_route(
			$this->namespace,
			'/admin/stats',
			array(
				array(
					'methods'             => WP_REST_Server::READABLE,
					'callback'            => array( $this, 'get_items' ),
					'permission_callback' => array( $this, 'permission_manage' ),
				),
			)
		);
	}

	/**
	 * Returns totals, cached for ten minutes.
	 *
	 * @param WP_REST_Request $request Request object.
	 * @return WP_REST_Response
	 */
	public function get_items( $request ) {
		unset( $request );

		$stats = get_transient( self::CACHE_KEY );

		if ( ! is_array( $stats ) ) {
			$stats = array(
				'members'  => self::count_members(),
				'spaces'   => self::count_spaces(),
				'posts'    => self::count( 'posts', 'status', 'published' ),
				'comments' => self::count( 'comments', 'status', 'published' ),
				'reports'  => \SpaceBay\Moderation\Reports::open_count(),
				'pending'  => count( \SpaceBay\Members\Profiles::ids_with_status( 'pending' ) ),
			);

			set_transient( self::CACHE_KEY, $stats, 10 * MINUTE_IN_SECONDS );
		}

		return rest_ensure_response( $stats );
	}

	/**
	 * Counts rows in a SpaceBay table with a given status.
	 *
	 * @param string $short_name Short table name.
	 * @param string $column     Status column name, from a fixed list.
	 * @param string $value      Status value.
	 * @return int
	 */
	private static function count( $short_name, $column, $value ) {
		global $wpdb;

		$table = Tables::name( $short_name );

		if ( '' === $table || 'status' !== $column ) {
			return 0;
		}

		return (int) $wpdb->get_var( // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- Custom table; result cached in a transient by the caller.
			$wpdb->prepare( 'SELECT COUNT(id) FROM %i WHERE status = %s', $table, $value )
		);
	}

	/**
	 * Counts published spaces, not space groups.
	 *
	 * @return int
	 */
	private static function count_spaces() {
		global $wpdb;

		return (int) $wpdb->get_var( // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- Custom table; result cached in a transient by the caller.
			$wpdb->prepare( 'SELECT COUNT(id) FROM %i WHERE type = %s AND status = %s', Tables::name( 'spaces' ), 'space', 'published' )
		);
	}

	/**
	 * Counts registered members of the site.
	 *
	 * @return int
	 */
	private static function count_members() {
		$counts = count_users();

		return isset( $counts['total_users'] ) ? (int) $counts['total_users'] : 0;
	}
}