<?php
/**
 * Convert one normalized server observation into a Finding contract.
 *
 * @package Px320\SiteAudit
 */

declare(strict_types=1);

namespace Px320\SiteAudit\Server;

use Px320\SiteAudit\Checks\Checker;
use Px320\SiteAudit\Checks\FindingFactory;

final class ServerFindingChecker implements Checker {
	private string $check_id;
	private FindingFactory $factory;
	private ServerObservationSet $observations;

	public function __construct( string $check_id, FindingFactory $factory, ServerObservationSet $observations ) {
		if ( ! in_array( $check_id, ServerObservationSet::check_ids(), true ) ) {
			throw new \InvalidArgumentException( 'unknown_server_checker' );
		}

		$this->check_id     = $check_id;
		$this->factory      = $factory;
		$this->observations = $observations;
	}

	public function id(): string {
		return $this->check_id;
	}

	/**
	 * @return array<string, mixed>
	 */
	public function execute( string $timestamp ): array {
		$section = $this->observations->section( $this->check_id );
		$state   = (string) $section['state'];
		$status  = $this->status( $section );
		$total   = (int) $section['total'];
		$seen    = (int) $section['observed'];

		if ( 0 === $seen || in_array( $state, array( 'permission_denied', 'not_applicable', 'not_tested' ), true ) ) {
			$coverage = 'none';
		} elseif ( 'error' === $state ) {
			$coverage = 'error';
		} elseif ( $seen < $total || 'partial' === $state ) {
			$coverage = 'partial';
		} else {
			$coverage = 'complete';
		}

		$evidence = array(
			'capability' => $section['capability'],
			'state'      => $state,
		);
		foreach ( array( 'values', 'masked_paths', 'permission', 'limitations' ) as $key ) {
			if ( array() !== $section[ $key ] && '' !== $section[ $key ] ) {
				$evidence[ $key ] = $section[ $key ];
			}
		}

		return $this->factory->build( $this->check_id, $status, $evidence, $seen, $total, $coverage, $timestamp );
	}

	/**
	 * @param array<string, mixed> $section Observation section.
	 */
	private function status( array $section ): string {
		$state  = (string) $section['state'];
		$values = $section['values'];
		if ( 'error' === $state ) {
			return 'error';
		}
		if ( in_array( $state, array( 'permission_denied', 'not_applicable', 'not_tested' ), true ) ) {
			return 'not_tested';
		}
		if ( 'server.filesystem_resources' === $this->check_id && isset( $values['disk_free_band'] ) ) {
			if ( 'low' === $values['disk_free_band'] ) {
				return 'fail';
			}
			if ( 'watch' === $values['disk_free_band'] ) {
				return 'warning';
			}
		}
		if ( 'server.scheduled_work' === $this->check_id && 'disabled' === ( $values['wp_cron_state'] ?? null ) && 'not_tested' === ( $values['system_timer_state'] ?? null ) ) {
			return 'warning';
		}
		if ( 'server.tls_http' === $this->check_id && 'http' === ( $values['home_scheme'] ?? null ) ) {
			return 'warning';
		}
		if ( 'server.integrity' === $this->check_id && 'partial' === $state ) {
			return 'not_tested';
		}

		return 'available' === $state ? 'pass' : 'info';
	}
}