<?php

declare (strict_types=1);
namespace PhpParser\Lexer\TokenEmulator;

use PhpParser\Lexer\Emulative;
final class NullsafeTokenEmulator extends \PhpParser\Lexer\TokenEmulator\TokenEmulator
{
    public function getPhpVersion() : string
    {
        return Emulative::PHP_8_0;
    }
    public function isEmulationNeeded(string $code) : bool
    {
        return \strpos($code, '?->') !== \false;
    }
    public function emulate(string $code, array $tokens) : array
    {
        // We need to manually iterate and manage a count because we'll change
        // the tokens array on the way
        $line = 1;
        for ($i = 0, $c = \count($tokens); $i < $c; ++$i) {
            if ($tokens[$i] === '?' && isset($tokens[$i + 1]) && $tokens[$i + 1][0] === \T_OBJECT_OPERATOR) {
                \array_splice($tokens, $i, 2, [[\T_NULLSAFE_OBJECT_OPERATOR, '?->', $line]]);
                $c--;
                continue;
            }
            // Handle ?-> inside encapsed string.
            if ($tokens[$i][0] === \T_ENCAPSED_AND_WHITESPACE && isset($tokens[$i - 1]) && $tokens[$i - 1][0] === \T_VARIABLE && \preg_match('/^\\?->([a-zA-Z_\\x80-\\xff][a-zA-Z0-9_\\x80-\\xff]*)/', $tokens[$i][1], $matches)) {
                $replacement = [[\T_NULLSAFE_OBJECT_OPERATOR, '?->', $line], [\T_STRING, $matches[1], $line]];
                if (\strlen($matches[0]) !== \strlen($tokens[$i][1])) {
                    $replacement[] = [\T_ENCAPSED_AND_WHITESPACE, \substr($tokens[$i][1], \strlen($matches[0])), $line];
                }
                \array_splice($tokens, $i, 1, $replacement);
                $c += \count($replacement) - 1;
                continue;
            }
            if (\is_array($tokens[$i])) {
                $line += \substr_count($tokens[$i][1], "\n");
            }
        }
        return $tokens;
    }
    public function reverseEmulate(string $code, array $tokens) : array
    {
        // ?-> was not valid code previously, don't bother.
        return $tokens;
    }
}
