class FileGetContents

class FileGetContents extends AbstractRetriever {
    protected $messageBody;
    
    /**
     * {@inheritdoc}
     *
     * @see \JsonSchema\Uri\Retrievers\UriRetrieverInterface::retrieve()
     */
    public function retrieve($uri) {
        $errorMessage = null;
        set_error_handler(function ($errno, $errstr) use (&$errorMessage) {
            $errorMessage = $errstr;
        });
        $response = file_get_contents($uri);
        restore_error_handler();
        if ($errorMessage) {
            throw new ResourceNotFoundException($errorMessage);
        }
        if (false === $response) {
            throw new ResourceNotFoundException('JSON schema not found at ' . $uri);
        }
        if ($response == '' && substr($uri, 0, 7) == 'file://' && substr($uri, -1) == '/') {
            throw new ResourceNotFoundException('JSON schema not found at ' . $uri);
        }
        $this->messageBody = $response;
        if (!empty($http_response_header)) {
            // $http_response_header cannot be tested, because it's defined in the method's local scope
            // See http://php.net/manual/en/reserved.variables.httpresponseheader.php for more info.
            $this->fetchContentType($http_response_header);
            // @codeCoverageIgnore
        }
        else {
            // @codeCoverageIgnore
            // Could be a "file://" url or something else - fake up the response
            $this->contentType = null;
        }
        return $this->messageBody;
    }
    
    /**
     * @param array $headers HTTP Response Headers
     *
     * @return bool Whether the Content-Type header was found or not
     */
    private function fetchContentType(array $headers) {
        foreach ($headers as $header) {
            if ($this->contentType = self::getContentTypeMatchInHeader($header)) {
                return true;
            }
        }
        return false;
    }
    
    /**
     * @param string $header
     *
     * @return string|null
     */
    protected static function getContentTypeMatchInHeader($header) {
        if (0 < preg_match("/Content-Type:(\\V*)/ims", $header, $match)) {
            return trim($match[1]);
        }
        return null;
    }

}