<?php declare(strict_types = 1);

namespace SlevomatCodingStandard\Sniffs\Functions;

use PHP_CodeSniffer\Files\File;
use PHP_CodeSniffer\Sniffs\Sniff;
use SlevomatCodingStandard\Helpers\TokenHelper;
use const T_CLOSURE;
use const T_OPEN_PARENTHESIS;
use const T_PARENT;
use const T_STATIC;
use const T_STRING;
use const T_VARIABLE;

class StaticClosureSniff implements Sniff
{

	public const CODE_CLOSURE_NOT_STATIC = 'ClosureNotStatic';

	/**
	 * @return mixed[]
	 */
	public function register(): array
	{
		return [
			T_CLOSURE,
		];
	}

	/**
	 * @phpcsSuppress SlevomatCodingStandard.TypeHints.TypeHintDeclaration.MissingParameterTypeHint
	 * @param \PHP_CodeSniffer\Files\File $phpcsFile
	 * @param int $closurePointer
	 */
	public function process(File $phpcsFile, $closurePointer): void
	{
		$tokens = $phpcsFile->getTokens();

		$previousPointer = TokenHelper::findPreviousEffective($phpcsFile, $closurePointer - 1);
		if ($tokens[$previousPointer]['code'] === T_STATIC) {
			return;
		}

		if ($tokens[$previousPointer]['code'] === T_OPEN_PARENTHESIS) {
			$pointerBeforeParenthesis = TokenHelper::findPreviousEffective($phpcsFile, $previousPointer - 1);
			if (
				$tokens[$pointerBeforeParenthesis]['code'] === T_STRING
				&& $tokens[$pointerBeforeParenthesis]['content'] === 'bind'
			) {
				return;
			}
		}

		$thisPointer = TokenHelper::findNextContent($phpcsFile, T_VARIABLE, '$this', $tokens[$closurePointer]['scope_opener'] + 1, $tokens[$closurePointer]['scope_closer']);
		if ($thisPointer !== null) {
			return;
		}

		$parentPointer = TokenHelper::findNext($phpcsFile, T_PARENT, $tokens[$closurePointer]['scope_opener'] + 1, $tokens[$closurePointer]['scope_closer']);
		if ($parentPointer !== null) {
			return;
		}

		$fix = $phpcsFile->addFixableError('Closure not using "$this" should be declared static.', $closurePointer, self::CODE_CLOSURE_NOT_STATIC);

		if (!$fix) {
			return;
		}

		$phpcsFile->fixer->beginChangeset();
		$phpcsFile->fixer->addContentBefore($closurePointer, 'static ');
		$phpcsFile->fixer->endChangeset();
	}

}