<?php

namespace App\Services\Documents;

class TokenScanner
{
    private const REGEX = '/{{\s*([a-zA-Z0-9_]+\.[a-zA-Z0-9_]+)\s*}}/';

    /**
     * @return array<int,string>
     */
    public function scan(string $content): array
    {
        preg_match_all(self::REGEX, $content, $m);
        if (empty($m[1])) {
            return [];
        }

        return array_values(array_unique($m[1]));
    }
}