<?php
/**
 * Collects all checks and runs them.
 *
 * @package Keepwatch
 */

namespace Keepwatch\Checks;

use Keepwatch\Errors\ErrorStore;
use Keepwatch\Support\Redactor;

defined( 'ABSPATH' ) || exit;

/**
 * Builds the list of checks. Other modules (e.g. WooCommerce) add theirs with the
 * "keepwatch_checks" filter, so the core works without WooCommerce.
 */
final class Registry {

	/**
	 * Default checks.
	 *
	 * @return Check[]
	 */
	public static function checks(): array {
		$checks = array(
			new FatalErrorsCheck( new ErrorStore() ),
			new UpdatesCheck(),
			new SiteHealthCheck(),
			new CronCheck(),
			new VisibilityCheck(),
			new EnvironmentCheck(),
			new ServerCheck(),
			new DatabaseCheck(),
			new SecurityCheck(),
			new BackupCheck(),
		);

		/**
		 * Filters the checks Keepwatch runs. Third-party callbacks may return anything, so the result
		 * is validated below.
		 *
		 * @param mixed $checks Check instances.
		 */
		$filtered = apply_filters( 'keepwatch_checks', $checks );

		return array_values(
			array_filter(
				is_array( $filtered ) ? $filtered : $checks,
				static function ( $check ): bool {
					return $check instanceof Check;
				}
			)
		);
	}

	/**
	 * Run every check; a failing check never breaks the dashboard.
	 *
	 * @param Check[] $checks Checks to run.
	 * @return array<string, Result[]> Results grouped by check group, each group sorted critical-first.
	 */
	public static function run( array $checks ): array {
		$groups = array();
		foreach ( $checks as $check ) {
			try {
				$results = $check->run();
			} catch ( \Throwable $e ) {
				$results = array(
					new Result(
						'check.failed',
						Result::RECOMMENDED,
						__( 'A check could not run', 'keepwatch' ),
						Redactor::redact( $e->getMessage() )
					),
				);
			}
			$group = $check->group();
			if ( ! isset( $groups[ $group ] ) ) {
				$groups[ $group ] = array();
			}
			$groups[ $group ] = array_merge( $groups[ $group ], $results );
		}

		foreach ( $groups as $group => $results ) {
			usort(
				$results,
				static function ( Result $a, Result $b ): int {
					return $a->weight() <=> $b->weight();
				}
			);
			$groups[ $group ] = $results;
		}

		return $groups;
	}

	/**
	 * Count results per status.
	 *
	 * @param array<string, Result[]> $groups Grouped results.
	 * @return array{good: int, recommended: int, critical: int}
	 */
	public static function summary( array $groups ): array {
		$summary = array(
			'good'        => 0,
			'recommended' => 0,
			'critical'    => 0,
		);
		foreach ( $groups as $results ) {
			foreach ( $results as $result ) {
				if ( isset( $summary[ $result->status ] ) ) {
					++$summary[ $result->status ];
				}
			}
		}
		return $summary;
	}
}