<?php
/**
 * Missing translations (F-COMMERCE-01) and untranslated titles and descriptions (F-COMMERCE-02).
 *
 * @package ForensixDigital
 */

declare(strict_types=1);

namespace ForensixDigital\Apps\Commerce;

defined( 'ABSPATH' ) || exit;

use ForensixDigital\Services\Findings\FindingStore;
use ForensixDigital\Services\Findings\Observation;
use ForensixDigital\Services\Findings\Priority;
use ForensixDigital\Services\Scan\StoredContentCheck;
use ForensixDigital\Services\Seo\SeoProvider;
use ForensixDigital\Services\Sources\Source;
use ForensixDigital\Services\Sources\SourceLabels;

/**
 * With Polylang or WPML active, reads published pages and posts, 40 per step, and suggests the
 * languages each one has no translation in. A translation whose title or search description is
 * the same as on the page in the main language is suggested for review too. Read-only; all of
 * these are suggestions, because some pages are meant for one language only and some names do
 * not change between languages.
 */
final class TranslationCheck implements StoredContentCheck {

	private const PER_STEP = 40;

	/**
	 * SEO titles and descriptions, created on first use.
	 *
	 * @var SeoProvider|null
	 */
	private ?SeoProvider $seo = null;

	/**
	 * Creates the check.
	 *
	 * @param string       $app   App id the findings belong to.
	 * @param FindingStore $store Findings.
	 */
	public function __construct( private string $app, private FindingStore $store ) {}

	/**
	 * Handles one batch of pages and posts.
	 *
	 * @param int                  $scan_id Scan id.
	 * @param array<string, mixed> $cursor  Cursor with the last id seen.
	 * @return array<string, mixed>|null
	 */
	public function step( int $scan_id, array $cursor ): ?array {
		global $wpdb;
		$languages = Translations::languages();
		if ( count( $languages ) < 2 ) {
			return null;
		}
		$last = (int) ( $cursor['last'] ?? 0 );
		$rows = (array) $wpdb->get_results( // phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery, WordPress.DB.DirectDatabaseQuery.NoCaching -- Reads posts in batches.
			$wpdb->prepare(
				"SELECT ID, post_type, post_title FROM {$wpdb->posts} WHERE post_status = 'publish' AND post_type IN ('post','page') AND ID > %d ORDER BY ID ASC LIMIT %d", // phpcs:ignore WordPress.DB.PreparedSQL.InterpolatedNotPrepared -- Core table name.
				$last,
				self::PER_STEP
			)
		);
		foreach ( $rows as $row ) {
			$this->inspect( $scan_id, $row, $languages );
			$last = (int) $row->ID;
		}
		return count( $rows ) < self::PER_STEP ? null : array( 'last' => $last );
	}

	/**
	 * Checks one page or post.
	 *
	 * @param int                $scan_id   Scan id.
	 * @param \stdClass          $row       Post row.
	 * @param array<int, string> $languages Active language codes.
	 */
	private function inspect( int $scan_id, \stdClass $row, array $languages ): void {
		$id           = (int) $row->ID;
		$type         = (string) $row->post_type;
		$own          = Translations::language_of( $id, $type );
		$translations = Translations::of_post( $id, $type, $languages );
		$missing      = TranslationRules::missing( $languages, $own, $translations );
		if ( array() !== $missing ) {
			$this->record( $scan_id, $id, 'missing_translation', __( 'This page has no translation in some languages', 'forensix-digital' ), array( 'languages' => $missing ), implode( ', ', $missing ) );
		}

		// F-COMMERCE-02: a translation that kept the main language's title or description.
		$main     = Translations::default_language();
		$original = (int) ( $translations[ $main ] ?? 0 );
		if ( '' === $own || '' === $main || $own === $main || $original < 1 || $original === $id ) {
			return;
		}
		if ( null === $this->seo ) {
			$this->seo = new SeoProvider();
		}
		$mine     = $this->seo->read( $id );
		$theirs   = $this->seo->read( $original );
		$titles   = array(
			'same_title'       => __( 'This translation has the same title as the original', 'forensix-digital' ),
			'no_description'   => __( 'This translation has no search description', 'forensix-digital' ),
			'same_description' => __( 'This translation has the same search description as the original', 'forensix-digital' ),
		);
		$problems = TranslationRules::untranslated(
			array(
				'title'       => (string) $row->post_title,
				'description' => $mine['description'],
			),
			array(
				'title'       => get_the_title( $original ),
				'description' => $theirs['description'],
			)
		);
		foreach ( $problems as $name ) {
			$this->record( $scan_id, $id, 'translation.' . $name, $titles[ $name ], array( 'original' => $original ), $own );
		}
	}

	/**
	 * Records a suggestion about one page.
	 *
	 * @param int                  $scan_id Scan id.
	 * @param int                  $id      Post id.
	 * @param string               $name    Check name after "commerce.".
	 * @param string               $title   Finding title.
	 * @param array<string, mixed> $details Details.
	 * @param string               $context Context shown with the finding.
	 */
	private function record( int $scan_id, int $id, string $name, string $title, array $details, string $context ): void {
		$source = new Source( Source::POST_CONTENT, (string) $id );
		$link   = get_permalink( $id );
		$this->store->record(
			$scan_id,
			$this->app,
			new Observation(
				'commerce.' . $name,
				Priority::LOW,
				Priority::SUGGESTION,
				$title,
				false !== $link ? $link : home_url( '/' ),
				$source->type,
				$source->ref,
				( new SourceLabels() )->label( $source ),
				$details
			),
			(string) get_edit_post_link( $id, 'raw' ),
			$context
		);
	}
}