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<?php

    namespace CzProject\Configuration;

    use Nette;


    class Helpers
    {
        /**
         * Expands placeholders (%placeholder%)
         * @param  mixed
         * @param  array
         * @param  bool|array
         * @return mixed
         * @throws InvalidArgumentException
         * @see    https://github.com/nette/di/blob/master/src/DI/Helpers.php
         */
        public static function expandPlaceholders($var, array $params, $recursive = FALSE)
        {
            if (is_array($var)) {
                $res = array();

                foreach ($var as $key => $val) {
                    $res[$key] = self::expandPlaceholders($val, $params, $recursive);
                }

                return $res;

            } elseif (!is_string($var)) {
                return $var;
            }

            $parts = preg_split('#%([\w.-]*)%#i', $var, -1, PREG_SPLIT_DELIM_CAPTURE);
            $res = '';

            foreach ($parts as $n => $part) {
                if ($n % 2 === 0) {
                    $res .= $part;

                } elseif ($part === '') {
                    $res .= '%';

                } elseif (isset($recursive[$part])) {
                    throw new InvalidArgumentException(sprintf('Circular reference detected for variables: %s.', implode(', ', array_keys($recursive))));

                } else {
                    try {
                        $val = Nette\Utils\Arrays::get($params, explode('.', $part));

                    } catch (Nette\InvalidArgumentException $e) {
                        throw new InvalidArgumentException("Missing parameter '$part'.", 0, $e);
                    }

                    if ($recursive) {
                        $val = self::expandPlaceholders($val, $params, (is_array($recursive) ? $recursive : array()) + array($part => 1));
                    }

                    if (strlen($part) + 2 === strlen($var)) {
                        return $val;
                    }

                    if (!is_scalar($val)) {
                        throw new InvalidArgumentException("Unable to concatenate non-scalar parameter '$part' into '$var'.");
                    }

                    $res .= $val;
                }
            }

            return $res;
        }
    }