<?php declare(strict_types = 1);

namespace SlevomatCodingStandard\Helpers;

use PHPStan\PhpDocParser\Ast\Node;
use PHPStan\PhpDocParser\Ast\NodeTraverser;
use PHPStan\PhpDocParser\Ast\NodeVisitor\CloningVisitor;
use PHPStan\PhpDocParser\Lexer\Lexer;
use PHPStan\PhpDocParser\Parser\ConstExprParser;
use PHPStan\PhpDocParser\Parser\PhpDocParser;
use PHPStan\PhpDocParser\Parser\TypeParser;
use PHPStan\PhpDocParser\ParserConfig;
use PHPStan\PhpDocParser\Printer\Printer;

/**
 * @internal
 */
class PhpDocParserHelper
{

	public static function getLexer(): Lexer
	{
		static $lexer;

		$lexer ??= new Lexer(self::getConfig());

		return $lexer;
	}

	public static function getParser(): PhpDocParser
	{
		static $parser;

		if ($parser === null) {
			$config = self::getConfig();
			$constantExpressionParser = new ConstExprParser($config);
			$parser = new PhpDocParser(
				$config,
				new TypeParser($config, $constantExpressionParser),
				$constantExpressionParser,
			);
		}

		return $parser;
	}

	public static function getPrinter(): Printer
	{
		static $printer;

		$printer ??= new Printer();

		return $printer;
	}

	/**
	 * @template T of Node
	 * @param T $node
	 * @return T
	 */
	public static function cloneNode(Node $node): Node
	{
		static $cloningTraverser;

		$cloningTraverser ??= new NodeTraverser([new CloningVisitor()]);

		[$cloneNode] = $cloningTraverser->traverse([$node]);

		return $cloneNode;
	}

	private static function getConfig(): ParserConfig
	{
		static $config;

		$config ??= new ParserConfig(['lines' => true, 'indexes' => true]);

		return $config;
	}

}