date based on WP options.
	 *
	 * @since 4.0.0
	 *
	 * @param  null|int    $date   Date in UNIX timestamp format. Otherwise, current time.
	 * @return string              Date internationalized.
	 */
	public function formatDateAsI18n( $date = null ) {
		if ( ! $date ) {
			$date = time();
		}

		$format        = get_option( 'date_format' );
		$formattedDate = date_i18n( $format, $date );

		return apply_filters(
			'aioseo_format_date',
			$formattedDate,
			[
				$date,
				$format
			]
		);
	}

	/**
	 * Parses custom taxonomy tags by replacing them with the name of the first assigned term of the given taxonomy.
	 *
	 * @since 4.0.0
	 *
	 * @param  string $string The string to parse.
	 * @return mixed          The new title.
	 */
	private function parseTaxonomyNames( $string, $id ) { // phpcs:ignore VariableAnalysis.CodeAnalysis.VariableAnalysis.UnusedVariable
		$pattern = '/' . $this->denotationChar . 'tax_name-([a-zA-Z0-9_-]+)/im';
		$string  = preg_replace_callback( $pattern, [ $this, 'replaceTaxonomyName' ], $string );
		$pattern = '/' . $this->denotationChar . 'tax_name(?![a-zA-Z0-9_-])/im';

		return preg_replace( $pattern, '', $string );
	}

	/**
	 * Adds support for using #custom_field-[custom_field_title] for using
	 * custom fields / Advanced Custom Fields in titles / descriptions etc.
	 *
	 * @since 4.0.0
	 *
	 * @param  string $string The string to parse customs fields out of.
	 * @return mixed          The new title.
	 */
	public function parseCustomFields( $string ) {
		$pattern = '/' . $this->denotationChar . 'custom_field-([a-zA-Z0-9_-]+)/im';
		$string  = preg_replace_callback( $pattern, [ $this, 'replaceCustomField' ], $string );
		$pattern = '/' . $this->denotationChar . 'custom_field(?![a-zA-Z0-9_-])/im';

		return preg_replace( $pattern, '', $string );
	}

	/**
	 * Add context to our internal context.
	 *
	 * @since 4.0.0
	 *
	 * @param  array $context A context array to append.
	 * @return void
	 */
	public function addContext( $context ) {
		$this->context = array_merge( $this->context, $context );
	}

	/**
	 * Add tags to our internal tags.
	 *
	 * @since 4.0.0
	 *
	 * @param  array $tags A tags array to append.
	 * @return void
	 */
	public function addTags( $tags ) {
		$this->tags = array_merge( $this->tags, $tags );
	}

	/**
	 * Replaces a taxonomy name tag with its respective value.
	 *
	 * @since 4.0.0
	 *
	 * @param  array  $matches The matches.
	 * @return string          The replaced matches.
	 */
	private function replaceTaxonomyName( $matches ) {
		$termName = '';
		$post     = aioseo()->helpers->getPost();
		if ( ! empty( $matches[1] ) && $post ) {
			$taxonomy = get_taxonomy( $matches[1] );
			if ( ! $taxonomy ) {
				return '';
			}

			$term = aioseo()->standalone->primaryTerm->getPrimaryTerm( $post->ID, $taxonomy->name );
			if ( ! $term ) {
				$terms = get_the_terms( $post->ID, $taxonomy->name );
				if ( ! $terms || is_wp_error( $terms ) ) {
					return '';
				}

				$term = array_shift( $terms );
			}

			$termName = $term->name;
		}

		return '%|%' . $termName;
	}

	/**
	 * (ACF) Custom Field Replace.
	 *
	 * @since 4.0.0
	 *
	 * @param  array       $matches Array of matched values.
	 * @return bool|string          New title/text.
	 */
	private function replaceCustomField( $matches ) {
		$result = '';
		if ( ! empty( $matches ) ) {
			if ( ! empty( $matches[1] ) ) {
				if ( function_exists( 'get_field' ) ) {
					$result = get_field( $matches[1], get_queried_object() );
				}
				if ( empty( $result ) ) {
					global $post;
					if ( ! empty( $post ) ) {
						$result = get_post_meta( $post->ID, $matches[1], true );
					}
				}
			} else {
				$result = $matches[0];
			}
		}
		$result = wp_strip_all_tags( $result );

		return '%|%' . $result;
	}

	/**
	 * Get the default tags for the current post.
	 *
	 * @since 4.0.0
	 *
	 * @param  integer $postId The Post ID.
	 * @return array           An array of tags.
	 */
	public function getDefaultPostTags( $postId ) {
		$post = get_post( $postId );

		$title       = aioseo()->meta->title->getTitle( $post, true );
		$description = aioseo()->meta->description->getDescription( $post, true );

		return [
			'title'       => empty( $title ) ? '' : $title,
			'description' => empty( $description ) ? '' : $description
		];
	}
}