<?php

declare(strict_types=1);

namespace App\Cfnpp\Expression\Token;

use App\Cfnpp\Expression\Token;
use App\Cfnpp\Expression\TokenLiteral;
use App\Cfnpp\Expression\ICloudformationNative;

/**
 * Represents a reference to a CloudFormation parameter.
 *
 * @author Adam Pippin <hello@adampippin.ca>
 */
class Parameter extends TokenLiteral implements ICloudformationNative
{
	/**
	 * Name of the referenced parameter.
	 * @var string
	 */
	protected $name;

	/**
	 * New parameter.
	 * @string $name
	 * @param string $name
	 */
	public function __construct(string $name)
	{
		$this->name = $name;
	}

	/**
	 * Get the name of the parameter.
	 *
	 * @return string
	 */
	public function getName(): string
	{
		return $this->name;
	}

	public static function isToken(string $stream): bool
	{
		return (bool)preg_match('/^[A-Za-z]$/', $stream[0]);
	}

	public static function getToken(string &$stream): Token
	{
		$buffer = '';
		$buffer = $stream[0];
		for ($i = 1; $i < strlen($stream); $i++)
		{
			if (preg_match('/^[A-Za-z0-9]$/', $stream[$i]))
			{
				$buffer .= $stream[$i];
			}
			else
			{
				break;
			}
		}

		$stream = substr($stream, strlen($buffer));

		return new Parameter($buffer);
	}

	/**
	 * Get the value of this token.
	 *
	 * @param  ?\App\Util\GraphNode[]                $arguments
	 * @return \App\Util\GraphNode|Token|scalar|null
	 */
	public function execute(?array $arguments = null)
	{
		throw new \Exception('Unreplaced parameter');
	}

	/**
	 * Return the cloudformation representation of a reference to a parameter.
	 *
	 * @param  ?\App\Util\GraphNode[] $arguments
	 * @return mixed[]
	 */
	public function toCloudformation(?array $arguments = null): array
	{
		return ['Ref' => $this->getName()];
	}
}