<?php
/**
 * All in One SEO target keyword source.
 *
 * @package Postlinkly
 * @since   1.0.0
 */

declare(strict_types=1);

namespace Postlinkly\Keywords\Sources;

/**
 * Reads the focus keyword set by All in One SEO (AIOSEO) for a post.
 *
 * AIOSEO stores keyphrases in its own table `aioseo_posts` in a JSON
 * column `keyphrases`. The primary keyphrase is in `keyphrases.focus.keyphrase`.
 * Additional keyphrases are in `keyphrases.additional[*].keyphrase`.
 *
 * Availability is determined by checking for the `AIOSEO` class.
 *
 * @since 1.0.0
 */
final class AioseoSource implements KeywordSourceInterface {

	/**
	 * Source identifier.
	 */
	public const SOURCE_ID = 'aioseo';

	/**
	 * @since 1.0.0
	 */
	public function get_id(): string {
		return self::SOURCE_ID;
	}

	/**
	 * @since 1.0.0
	 */
	public function get_label(): string {
		return __( 'All in One SEO', 'postlinkly' );
	}

	/**
	 * @since 1.0.0
	 */
	public function is_available(): bool {
		return class_exists( 'AIOSEO\Plugin\AIOSEO', false );
	}

	/**
	 * @since 1.0.0
	 *
	 * @param int    $post_id   Post identifier.
	 * @param string $post_type Item type. Default `post`.
	 *
	 * @return array<int, string>
	 */
	public function get_keywords_for( int $post_id, string $post_type = 'post' ): array {
		global $wpdb;

		if ( $post_id <= 0 || 'post' !== $post_type || ! isset( $wpdb ) ) {
			return array();
		}

		$table = $wpdb->prefix . 'aioseo_posts';

		// phpcs:ignore WordPress.DB.DirectDatabaseQuery.DirectQuery,WordPress.DB.DirectDatabaseQuery.NoCaching -- AIOSEO has no public API for keyphrases; direct query is the only option.
		$row = $wpdb->get_row(
			$wpdb->prepare(
				'SELECT keyphrases FROM %i WHERE post_id = %d',
				$table,
				$post_id
			)
		);

		if ( ! is_object( $row ) || ! isset( $row->keyphrases ) || '' === $row->keyphrases ) {
			return array();
		}

		$data = json_decode( (string) $row->keyphrases, true );
		if ( ! is_array( $data ) ) {
			return array();
		}

		$out = array();

		// Primary focus keyphrase.
		$focus = $data['focus']['keyphrase'] ?? '';
		if ( is_string( $focus ) && '' !== trim( $focus ) ) {
			$out[] = trim( $focus );
		}

		// Additional keyphrases.
		$additional = $data['additional'] ?? array();
		if ( is_array( $additional ) ) {
			foreach ( $additional as $item ) {
				if ( ! is_array( $item ) ) {
					continue;
				}
				$kw = trim( (string) ( $item['keyphrase'] ?? '' ) );
				if ( '' !== $kw && ! in_array( $kw, $out, true ) ) {
					$out[] = $kw;
				}
			}
		}

		return $out;
	}
}