<?php
/**
 * Stream
 *
 * $Id$
 *
 * @author gERD Schaufelberger <gerd@php-tools.net>
 * @license PHP License
 * @package WB
 * @subpackage base
 */

/**
 * Stream
 *
 * Wrap stream
 *
 * @version 0.4.0
 * @package WB
 * @subpackage base
 */
class WBStream
{

    /**
     * kind of fopen
     *
     * Wrapper to fopen using proxy, if required
     *
     *
     * @throws WBException_File if stream could not be opened
     * @param string $url
     * @param string $mode fopen mode
     * @param bool $useIncludePath whether to use include path
     * @param array $contextOptions stream context options
     * @return resource
     */
    static public function open($url, $mode, $useIncludePath = false, $contextOptions = array())
    {
        // create strem context
        $context    =   self::getContext($url, $contextOptions);
        $resource   =   fopen($url, $mode, false, $context);
        if (!is_resource($resource)) {
            WBClass::load('WBException_File');
            throw new WBException_File('Could not open stream: "' . $url . '"', 1, __CLASS__);
        }
        return $resource;
    }

    /**
     * create stream context for URL
     *
     * Load context options on demand.
     *
     * @param string $url
     * @param array $contextOptions stream context options
     * @return stream context
     */
    static private function getContext($url, $contextOptions = array())
    {
        $options    =   self::getStreamContextOptions($url, $contextOptions);
        return stream_context_create($options);
    }

    /**
     * Get context options
     *
     * @param string $url
     * @param array $contextOptions stream context options
     * @return array stream context options
     */
    static public function getStreamContextOptions($url, $contextOptions = array())
    {
        $type   =   'file';
        if (strncmp($url, 'http://', 7) == 0 || strncmp($url, 'https://', 8) == 0) {
            $type   =   'http';
        }

        $option =   array();
        if (isset($contextOptions['ssl'])) {
            $option['ssl']      =   $contextOptions['ssl'];
            unset($contextOptions['ssl']);
        }
        if (isset($contextOptions['socket'])) {
            $option['socket']   =   $contextOptions['socket'];
            unset($contextOptions['socket']);
        }

        switch ($type) {
            // proxy support for HTTP
            case 'http':
                $option['http'] =   array();
                $conf   =   WBClass::Create('WBConfig');
                /** @var conf WBConfig */
                $conf->load('config');
                $net    =   $conf->get('network/http', array());
                if (isset($net['proxy']) && $net['proxy']) {
                    $option['http']['proxy']           = $net['proxy'];
                    $option['http']['request_fulluri'] = true;
                }
                if (isset($net['useragent']) && $net['useragent']) {
                    $option['http']['user_agent']   =   $net['useragent'];
                }

                $option['http'] =   array_merge($option['http'], $contextOptions);
                break;

            case 'file':
            default:
                break;
        }

        return $option;
    }

}