<?php
/**
 * SEOPress target keyword source.
 *
 * @package Postlinkly
 * @since   1.0.0
 */

declare(strict_types=1);

namespace Postlinkly\Keywords\Sources;

/**
 * Reads the target keyword set by SEOPress for a post.
 *
 * SEOPress stores the target keyword in `_seopress_analysis_target_kw`
 * post meta.
 *
 * Availability is determined by checking for the `SeoPress_Admin` class.
 *
 * @since 1.0.0
 */
final class SeoPressSource implements KeywordSourceInterface {

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

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

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

	/**
	 * @since 1.0.0
	 */
	public function is_available(): bool {
		return class_exists( 'SeoPress_Admin', 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 {
		if ( $post_id <= 0 || 'post' !== $post_type || ! function_exists( 'get_post_meta' ) ) {
			return array();
		}

		$raw = get_post_meta( $post_id, '_seopress_analysis_target_kw', true );
		if ( ! is_string( $raw ) || '' === trim( $raw ) ) {
			return array();
		}

		return array( trim( $raw ) );
	}
}