Requests::set_defaults

	 * @return array $options
	 */
	protected static function set_defaults(&$url, &$headers, &$data, &$type, &$options) {
		if (!preg_match('/^http(s)?:\/\//i', $url, $matches)) {
			throw new Requests_Exception('Only HTTP(S) requests are handled.', 'nonhttp', $url);
		}

		if (empty($options['hooks'])) {
			$options['hooks'] = new Requests_Hooks();
		}

		if (is_array($options['auth'])) {
			$options['auth'] = new Requests_Auth_Basic($options['auth']);
		}
		if ($options['auth'] !== false) {
			$options['auth']->register($options['hooks']);
		}

		if (is_string($options['proxy']) || is_array($options['proxy'])) {
			$options['proxy'] = new Requests_Proxy_HTTP($options['proxy']);
		}
		if ($options['proxy'] !== false) {
			$options['proxy']->register($options['hooks']);
		}

		if (is_array($options['cookies'])) {
			$options['cookies'] = new Requests_Cookie_Jar($options['cookies']);
		}
		elseif (empty($options['cookies'])) {
			$options['cookies'] = new Requests_Cookie_Jar();
		}
		if ($options['cookies'] !== false) {
			$options['cookies']->register($options['hooks']);
		}

		if ($options['idn'] !== false) {
			$iri = new Requests_IRI($url);
			$iri->host = Requests_IDNAEncoder::encode($iri->ihost);
			$url = $iri->uri;
		}

		// Massage the type to ensure we support it.
		$type = strtoupper($type);

		if (!isset($options['data_format'])) {
			if (in_array($type, array(self::HEAD, self::GET, self::DELETE))) {
				$options['data_format'] = 'query';
			}
			else {
				$options['data_format'] = 'body';
			}