description;
	}

	/**
	 * Get robots after sanitization.
	 *
	 * @return array
	 */
	public function get_robots() {
		if ( ! is_null( $this->robots ) ) {
			return $this->robots;
		}

		$this->robots = $this->paper->robots();
		if ( empty( $this->robots ) ) {
			$this->robots = self::robots_combine( Helper::get_settings( 'titles.robots_global' ) );
		}
		$this->validate_robots();
		$this->respect_settings_for_robots();

		/**
		 * Allows filtering of the meta robots.
		 *
		 * @param array $robots The meta robots directives to be echoed.
		 */
		$this->robots = $this->do_filter( 'frontend/robots', array_unique( $this->robots ) );
		$this->advanced_robots();

		return $this->robots;
	}

	/**
	 * Validate robots.
	 */
	private function validate_robots() {
		if ( empty( $this->robots ) || ! is_array( $this->robots ) ) {
			$this->robots = [
				'index'  => 'index',
				'follow' => 'follow',
			];
			return;
		}

		$this->robots = array_intersect_key(
			$this->robots,
			[
				'index'        => '',
				'follow'       => '',
				'noarchive'    => '',
				'noimageindex' => '',
				'nosnippet'    => '',
			]
		);

		// Add Index and Follow.
		if ( ! isset( $this->robots['index'] ) ) {
			$this->robots = [ 'index' => 'index' ] + $this->robots;
		}
		if ( ! isset( $this->robots['follow'] ) ) {
			$this->robots = [ 'follow' => 'follow' ] + $this->robots;
		}
	}

	/**
	 * Add Advanced robots.
	 */
	private function advanced_robots() {
		// Early Bail if robots is set to noindex or nosnippet!
		if ( ( isset( $this->robots['index'] ) && 'noindex' === $this->robots['index'] ) || ( isset( $this->robots['nosnippet'] ) && 'nosnippet' === $this->robots['nosnippet'] ) ) {
			return;
		}

		$advanced_robots = $this->paper->advanced_robots();
		if ( ! is_array( $advanced_robots ) ) {
			$advanced_robots = wp_parse_args(
				Helper::get_settings( 'titles.advanced_robots_global' ),
				[
					'max-snippet'       => -1,
					'max-video-preview' => -1,
					'max-image-preview' => 'large',
				]
			);

			$advanced_robots = self::advanced_robots_combine( $advanced_robots );
		}

		$advanced_robots = array_intersect_key(
			$advanced_robots,
			[
				'max-snippet'       => '',
				'max-video-preview' => '',
				'max-image-preview' => '',
			]
		);

		/**
		 * Allows filtering of the advanced meta robots.
		 *
		 * @param array $robots The meta robots directives to be echoed.
		 */
		$advanced_robots = $this->do_filter( 'frontend/advanced_robots', array_unique( $advanced_robots ) );

		$this->robots = ! empty( $advanced_robots ) ? $this->robots + $advanced_robots : $this->robots;
	}

	/**
	 * Get focus keywords
	 *
	 * @return string
	 */
	public function get_keywords() {
		if ( ! is_null( $this->keywords ) ) {
			return $this->keywords;
		}

		/**
		 * Allows filtering of the meta keywords.
		 *
		 * @param array $keywords The meta keywords to be echoed.
		 */
		$this->keywords = $this->do_filter( 'frontend/keywords', $this->paper->keywords() );

		return $this->keywords;
	}

	/**
	 * Respect some robots settings.
	 */
	private function respect_settings_for_robots() {
		// If blog is not public or replytocom is set, then force noindex.
		if ( 0 === absint( get_option( 'blog_public' ) ) || isset( $_GET['replytocom'] ) ) {
			$this->robots['index']  = 'noindex';
			$this->robots['follow'] = 'nofollow';
		}

		// Force noindex for sub-pages.
		if ( is_paged() && Helper::get_settings( 'titles.noindex_archive_subpages' ) ) {
			$this->robots['index'] = 'noindex';
		}
	}

	/**
	 * Get canonical after sanitization.
	 *
	 * @param bool $un_paged    Whether or not to return the canonical with or without pagination added to the URL.
	 * @param bool $no_override Whether or not to return a manually overridden canonical.
	 *
	 * @return string
	 */
	public function get_canonical( $un_paged = false, $no_override = false ) {
		if ( is_null( $this->canonical ) ) {
			$this->generate_canonical();
		}

		$canonical = $this->canonical['canonical'];
		if ( $un_paged ) {
			$canonical = $this->canonical['canonical_unpaged'];
		} elseif ( $no_override ) {
			$canonical = $this->canonical['canonical_no_override'];
		}

		return $canonical;
	}

	/**
	 * Generate canonical URL parts.
	 */
	private function generate_canonical() {
		$this->canonical = wp_parse_args(
			$this->paper->canonical(),
			[
				'canonical'          => false,
				'canonical_unpaged'  => false,
				'canonical_override' => false,
			]
		);
		extract( $this->canonical ); // phpcs:ignore

		if ( is_front_page() || ( function_exists( 'ampforwp_is_front_page' ) && ampforwp_is_front_page() ) ) {
			$canonical = user_trailingslashit( home_url() );
		}

		// If not singular than we can have pagination.
		if ( ! is_singular() ) {
			$canonical_unpaged = $canonical;
			$canonical         = $this->get_canonical_paged( $canonical );
		}

		$this->canonical['canonical_unpaged']     = $canonical_unpaged;
		$this->canonical['canonical_no_override'] = $canonical;

		// Force absolute URLs for canonicals.
		$canonical = Str::is_non_empty( $canonical ) && true === Url::is_relative( $canonical ) ? $this->base_url( $canonical ) : $canonical;
		$canonical = Str::is_non_empty( $canonical_override ) ? $canonical_override : $canonical;

		/**
		 * Filter the canonical URL.
		 *
		 * @param string $canonical The canonical URL.
		 */
		$this->canonical['canonical'] = apply_filters( 'rank_math/frontend/canonical', $canonical );
	}

	/**
	 * Get the paged version of the canonical URL if needed.
	 *
	 * @param string $canonical The canonical URL.
	 *
	 * @return string
	 */
	private function get_canonical_paged( $canonical ) {
		global $wp_rewrite;

		if ( ! $canonical || get_query_var( 'paged' ) < 2 ) {
			return $canonical;
		}

		if ( ! $wp_rewrite->using_permalinks() ) {
			return Security::add_query_arg_raw(
				'paged',
				get_query_var( 'paged' ),
				is_front_page() ? trailingslashit( $canonical ) : $canonical
			);
		}

		return user_trailingslashit(
			trailingslashit( is_front_page() ? Router::get_base_url( '' ) : $canonical ) .
			trailingslashit( $wp_rewrite->pagination_base ) .
			get_query_var( 'paged' )
		);
	}

	/**
	 * Get the base URL for relative URLs by parsing the home URL.
	 *
	 * @copyright Copyright (C) 2008-2019, Yoast BV
	 * The following code is a derivative work of the code from the Yoast (https://github.com/Yoast/wordpress-seo/), which is licensed under GPL v3.
	 *
	 * @param  string $path Optional path string.
	 * @return string
	 */
	private function base_url( $path = null ) {
		$parts    = wp_parse_url( get_option( 'home' ) );
		$base_url = trailingslashit( $parts['scheme'] . '://' . $parts['host'] );

		if ( ! is_null( $path ) ) {
			$base_url .= ltrim( $path, '/' );
		}

		return $base_url;
	}

	/**
	 * Get title or description option from the settings.
	 * The results will be run through the Helper::replace_vars() function.
	 *
	 * @param string       $id            Name of the option we are looking for.
	 * @param object|array $args          Object to pass to the replace_vars function.
	 * @param string       $default_value Default value if nothing found.
	 *
	 * @return string
	 */
	public static function get_from_options( $id, $args = [], $default_value = '' ) {
		$value = Helper::get_settings( "titles.$id" );

		// Break loop.
		if ( ! Str::ends_with( 'default_snippet_name', $value ) && ! Str::ends_with( 'default_snippet_desc', $value ) ) {
			$value = \str_replace(
				[ '%seo_title%', '%seo_description%' ],
				[ '%title%', '%excerpt%' ],
				$value
			);
		}

		return Helper::replace_vars( '' !== $value ? $value : $default_value, $args );
	}

	/**
	 * Make robots values as keyed array.
	 *
	 * @param array $robots        Main instance.
	 * @param bool  $default_value Append default.
	 *
	 * @return array
	 */
	public static function robots_combine( $robots, $default_value = false ) {
		if ( empty( $robots ) || ! is_array( $robots ) ) {
			return ! $default_value ? [] : [
				'index'  => 'index',
				'follow' => 'follow',
			];
		}

		$robots = array_combine( $robots, $robots );

		// Fix noindex key to index.
		if ( isset( $robots['noindex'] ) ) {
			$robots = [ 'index' => $robots['noindex'] ] + $robots;
			unset( $robots['noindex'] );
		}

		// Fix nofollow key to follow.
		if ( isset( $robots['nofollow'] ) ) {
			$robots = [ 'follow' => $robots['nofollow'] ] + $robots;
			unset( $robots['nofollow'] );
		}

		return $robots;
	}

	/**
	 * Make robots values as keyed array.
	 *
	 * @param array $advanced_robots  Main instance.
	 *
	 * @return array
	 */
	public static function advanced_robots_combine( $advanced_robots ) {
		if ( empty( $advanced_robots ) ) {
			return;
		}

		$robots = [];
		foreach ( $advanced_robots as $key => $data ) {
			if ( $data ) {
				$robots[ $key ] = $key . ':' . $data;
			}
		}
		return $robots;
	}

	/**
	 * Should apply shortcode on content.
	 *
	 * @return bool
	 */
	public static function should_apply_shortcode() {
		if (
			Post::is_woocommerce_page() ||
			( function_exists( 'is_wcfm_page' ) && is_wcfm_page() )
		) {
			return false;
		}

		return apply_filters( 'rank_math/paper/auto_generated_description/apply_shortcode', false );
	}

	/**
	 * Clears and reinitializes the object.
	 */
	public static function reset() {
		self::$instance = null;
		return self::get();
	}
}