<?php

namespace Glovario\Domain;

defined( 'ABSPATH' ) || exit;

final class NestedReferenceParser {
	public function replace( $value, $callback ) {
		if ( ! is_string( $value ) || false === strpos( $value, '[glvr' ) ) {
			return $value;
		}

		$pattern  = '/' . get_shortcode_regex( array( 'glvr' ) ) . '/s';
		$replaced = preg_replace_callback(
			$pattern,
			static function ( $matches ) use ( $callback ) {
				if ( '[' === $matches[1] && ']' === $matches[6] ) {
					return substr( $matches[0], 1, -1 );
				}
				$parsed     = shortcode_parse_atts( $matches[3] );
				$attributes = shortcode_atts(
					array(
						'key'      => '',
						'fallback' => '',
						'format'   => BuiltinVariables::DEFAULT_DATE_FORMAT,
					),
					is_array( $parsed ) ? $parsed : array(),
					'glvr'
				);
				return call_user_func( $callback, sanitize_key( $attributes['key'] ), (string) $attributes['fallback'], BuiltinVariables::sanitize_date_format( $attributes['format'] ) );
			},
			$value
		);
		return null === $replaced ? $value : $replaced;
	}

	public function keys( $value ) {
		$keys = array();
		$this->replace(
			$value,
			static function ( $key ) use ( &$keys ) {
				if ( '' !== $key ) {
					$keys[] = $key;
				}
				return '';
			}
		);
		return array_values( array_unique( $keys ) );
	}
}