<?php

declare (strict_types=1);
/*
 * This file is part of PHP CS Fixer.
 *
 * (c) Fabien Potencier <fabien@symfony.com>
 *     Dariusz Rumiński <dariusz.ruminski@gmail.com>
 *
 * This source file is subject to the MIT license that is bundled
 * with this source code in the file LICENSE.
 */
namespace PhpCsFixer\Tokenizer\Analyzer;

use PhpCsFixer\Tokenizer\Tokens;
/**
 * @internal
 *
 * @TODO 4.0 remove this analyzer and move this logic into a transformer
 */
final class AlternativeSyntaxAnalyzer
{
    private const ALTERNATIVE_SYNTAX_BLOCK_EDGES = [\T_IF => [\T_ENDIF, \T_ELSE, \T_ELSEIF], \T_ELSE => [\T_ENDIF], \T_ELSEIF => [\T_ENDIF, \T_ELSE, \T_ELSEIF], \T_FOR => [\T_ENDFOR], \T_FOREACH => [\T_ENDFOREACH], \T_WHILE => [\T_ENDWHILE], \T_SWITCH => [\T_ENDSWITCH]];
    public function belongsToAlternativeSyntax(Tokens $tokens, int $index) : bool
    {
        if (!$tokens[$index]->equals(':')) {
            return \false;
        }
        $prevIndex = $tokens->getPrevMeaningfulToken($index);
        if ($tokens[$prevIndex]->isGivenKind(\T_ELSE)) {
            return \true;
        }
        if (!$tokens[$prevIndex]->equals(')')) {
            return \false;
        }
        $openParenthesisIndex = $tokens->findBlockStart(Tokens::BLOCK_TYPE_PARENTHESIS_BRACE, $prevIndex);
        $beforeOpenParenthesisIndex = $tokens->getPrevMeaningfulToken($openParenthesisIndex);
        return $tokens[$beforeOpenParenthesisIndex]->isGivenKind([\T_DECLARE, \T_ELSEIF, \T_FOR, \T_FOREACH, \T_IF, \T_SWITCH, \T_WHILE]);
    }
    public function findAlternativeSyntaxBlockEnd(Tokens $tokens, int $index) : int
    {
        if (!isset($tokens[$index])) {
            throw new \InvalidArgumentException("There is no token at index {$index}.");
        }
        if (!$this->isStartOfAlternativeSyntaxBlock($tokens, $index)) {
            throw new \InvalidArgumentException("Token at index {$index} is not the start of an alternative syntax block.");
        }
        $startTokenKind = $tokens[$index]->getId();
        if (!isset(self::ALTERNATIVE_SYNTAX_BLOCK_EDGES[$startTokenKind])) {
            throw new \LogicException(\sprintf('Unknown startTokenKind: %s', $tokens[$index]->toJson()));
        }
        $endTokenKinds = self::ALTERNATIVE_SYNTAX_BLOCK_EDGES[$startTokenKind];
        $findKinds = [[$startTokenKind]];
        foreach ($endTokenKinds as $endTokenKind) {
            $findKinds[] = [$endTokenKind];
        }
        while (\true) {
            $index = $tokens->getNextTokenOfKind($index, $findKinds);
            if ($tokens[$index]->isGivenKind($endTokenKinds)) {
                return $index;
            }
            if ($this->isStartOfAlternativeSyntaxBlock($tokens, $index)) {
                $index = $this->findAlternativeSyntaxBlockEnd($tokens, $index);
            }
        }
    }
    private function isStartOfAlternativeSyntaxBlock(Tokens $tokens, int $index) : bool
    {
        $map = self::ALTERNATIVE_SYNTAX_BLOCK_EDGES;
        $startTokenKind = $tokens[$index]->getId();
        if (null === $startTokenKind || !isset($map[$startTokenKind])) {
            return \false;
        }
        $index = $tokens->getNextMeaningfulToken($index);
        if ($tokens[$index]->equals('(')) {
            $index = $tokens->getNextMeaningfulToken($tokens->findBlockEnd(Tokens::BLOCK_TYPE_PARENTHESIS_BRACE, $index));
        }
        return $tokens[$index]->equals(':');
    }
}
