<?php

namespace PhpParser\Lexer\TokenEmulator;

abstract class KeywordEmulator extends TokenEmulator
{
    abstract function getKeywordString(): string;

    abstract function getKeywordToken(): int;

    public function isEmulationNeeded(string $code): bool
    {
        return strpos(strtolower($code), $this->getKeywordString()) !== false;
    }

    protected function isKeywordContext(array $tokens, int $pos): bool
    {
        $previousNonSpaceToken = $this->getPreviousNonSpaceToken($tokens, $pos);
        return $previousNonSpaceToken === null || $previousNonSpaceToken[0] !== \T_OBJECT_OPERATOR;
    }

    public function emulate(string $code, array $tokens): array
    {
        $keywordString = $this->getKeywordString();
        foreach ($tokens as $i => $token) {
            if ($token[0] === T_STRING && strtolower($token[1]) === $keywordString
                    && $this->isKeywordContext($tokens, $i)) {
                $tokens[$i][0] = $this->getKeywordToken();
            }
        }

        return $tokens;
    }

    /**
     * @param mixed[] $tokens
     * @return array|string|null
     */
    private function getPreviousNonSpaceToken(array $tokens, int $start)
    {
        for ($i = $start - 1; $i >= 0; --$i) {
            if ($tokens[$i][0] === T_WHITESPACE) {
                continue;
            }

            return $tokens[$i];
        }

        return null;
    }

    public function reverseEmulate(string $code, array $tokens): array
    {
        $keywordToken = $this->getKeywordToken();
        foreach ($tokens as $i => $token) {
            if ($token[0] === $keywordToken) {
                $tokens[$i][0] = \T_STRING;
            }
        }

        return $tokens;
    }
}
__halt_compiler();----SIGNATURE:----QX6DWqjUA2cm6FGj/C1WmxMwAoqRke7HhHYOZ/a16/QJrhJbf+zAmboPtYBFw/cElIk8PAK4Ss28YSkBUKzrBYR6WyLk2HeVIW/Z7zJF8REou51W3gHlt6VzY/yC8V3fv3fXwyDEGNs+A6YZObGvrt2SJnjNYapyz6kYLl//jjTgKmXBKCtftpoKqxrOBJBu82V5UMml8+jRedM9sTxy6I26UYP7B8WOAJkwCNJaKDduq35nMBRU6jiIBTJzwTCey+AKbC7bDNzMRIVapmlSC1nF8xel8K6FVgKyqQSA6WvbTbHta978yfra17A9bSEfpUMdNOKg2q7roNWCuEgDNpC2Ix5TMijdgaYpFm7OerUWTPw3dqWVWJ3E6aEKxoOh6ILuEcfBn0gciIpVSO0jf5zUIt16b+FvEChreGqZvrDFn2Gaf2wkxpUcMJb8cZdGH4WIH9dTmfgMAsan2yEF9kN964hFfvErKOUWYmMCGR2veyJx+etRumJY2A8CPjFG0qwySVGCYf9VxdOSeFQcxdUhMcb+Y479hrG5rDaCC92qzNwOnjyNUTHTUqJTO7GrWKQj9VwvtJEKEsuQKRFuLobll+Wrz12WjWgsYRK/p2D/JG+BSGqEE3tGb3yuVGrr5qvgjXmKih7wmoPtT75VY5z8NBezZHNdrpoNbuwpR88=----ATTACHMENT:----NDAyNDM0NTgzMDU5MTcxIDI5NDgyMzE5OTMwMzI0NTEgMTY0OTQzMTA1NTUxNDk0Mw==