<?php
/**
 *  @author    DeoTemplate <deotemplate@gmail.com>
 *  @copyright by DeoTemplate
 *  @license   http://deotemplate.com - prestashop template provider
 */
if (!defined('_PS_VERSION_')) { exit; }

class OAuthUtil
{

    public static function urlencodeRfc3986($input)
    {
        if (is_array($input)) {
            return array_map(array('OAuthUtil', 'urlencodeRfc3986'), $input);
        } else if (is_scalar($input)) {
            return str_replace('+', ' ', str_replace('%7E', '~', rawurlencode($input)));
        } else {
            return '';
        }
    }

    // This decode function isn't taking into consideration the above
    // modifications to the encoding process. However, this method doesn't
    // seem to be used anywhere so leaving it as is.
    public static function urldecodeRfc3986($string)
    {
        return urldecode($string);
    }

    // Utility function for turning the Authorization: header into
    // parameters, has to do some unescaping
    // Can filter out any non-oauth parameters if needed (default behaviour)
    public static function splitHeader($header, $only_allow_oauth_parameters = true)
    {
        $pattern = '/(([-_a-z]*)=("([^"]*)"|([^,]*)),?)/';
        $offset = 0;
        $params = array();
        while (preg_match($pattern, $header, $matches, PREG_OFFSET_CAPTURE, $offset) > 0) {
            $match = $matches[0];
            $header_name = $matches[2][0];
            $header_content = (isset($matches[5])) ? $matches[5][0] : $matches[4][0];
            if (preg_match('/^oauth_/', $header_name) || !$only_allow_oauth_parameters) {
                $params[$header_name] = OAuthUtil::urldecodeRfc3986($header_content);
            }
            $offset = $match[1] + Tools::strlen($match[0]);
        }

        if (isset($params['realm'])) {
            unset($params['realm']);
        }

        return $params;
    }

    // helper to try to sort out headers for people who aren't running apache
    public static function getHeaders()
    {
        if (function_exists('apache_request_headers')) {
            // we need this to get the actual Authorization: header
            // because apache tends to tell us it doesn't exist
            $headers = apache_request_headers();

            // sanitize the output of apache_request_headers because
            // we always want the keys to be Cased-Like-This and arh()
            // returns the headers in the same case as they are in the
            // request
            $out = array();
            foreach ($headers as $key => $value) {
                $key = str_replace(" ", "-", ucwords(Tools::strtolower(str_replace("-", " ", $key))));
                $out[$key] = $value;
            }
        } else {
            // otherwise we don't have apache and are just going to have to hope
            // that $_SERVER actually contains what we need
            $out = array();
            if (isset($_SERVER['CONTENT_TYPE'])) {
                $out['Content-Type'] = $_SERVER['CONTENT_TYPE'];
            }
            if (isset($_ENV['CONTENT_TYPE'])) {
                $out['Content-Type'] = $_ENV['CONTENT_TYPE'];
            }

            foreach ($_SERVER as $key => $value) {
                if (Tools::substr($key, 0, 5) == "HTTP_") {
                    // this is chaos, basically it is just there to capitalize the first
                    // letter of every word that is not an initial HTTP and strip HTTP
                    // code from przemek
                    $key = str_replace(" ", "-", ucwords(Tools::strtolower(str_replace("_", " ", Tools::substr($key, 5)))));
                    $out[$key] = $value;
                }
            }
        }
        return $out;
    }

    // This function takes a input like a=b&a=c&d=e and returns the parsed
    // parameters like this
    // array('a' => array('b','c'), 'd' => 'e')
    public static function parseParameters($input)
    {
        if (!isset($input) || !$input) {
            return array();
        }

        $pairs = explode('&', $input);

        $parsed_parameters = array();
        foreach ($pairs as $pair) {
            $split = explode('=', $pair, 2);
            $parameter = OAuthUtil::urldecodeRfc3986($split[0]);
            $value = isset($split[1]) ? OAuthUtil::urldecodeRfc3986($split[1]) : '';

            if (isset($parsed_parameters[$parameter])) {
                // We have already recieved parameter(s) with this name, so add to the list
                // of parameters with this name

                if (is_scalar($parsed_parameters[$parameter])) {
                    // This is the first duplicate, so transform scalar (string) into an array
                    // so we can add the duplicates
                    $parsed_parameters[$parameter] = array($parsed_parameters[$parameter]);
                }

                $parsed_parameters[$parameter][] = $value;
            } else {
                $parsed_parameters[$parameter] = $value;
            }
        }
        return $parsed_parameters;
    }

    public static function buildHttpQuery($params)
    {
        if (!$params) {
            return '';
        }

        // Urlencode both keys and values
        $keys = OAuthUtil::urlencodeRfc3986(array_keys($params));
        $values = OAuthUtil::urlencodeRfc3986(array_values($params));
        $params = array_combine($keys, $values);

        // Parameters are sorted by name, using lexicographical byte value ordering.
        // Ref: Spec: 9.1.1 (1)
        uksort($params, 'strcmp');

        $pairs = array();
        foreach ($params as $parameter => $value) {
            if (is_array($value)) {
                // If two or more parameters share the same name, they are sorted by their value
                // Ref: Spec: 9.1.1 (1)
                natsort($value);
                foreach ($value as $duplicate_value) {
                    $pairs[] = $parameter . '=' . $duplicate_value;
                }
            } else {
                $pairs[] = $parameter . '=' . $value;
            }
        }
        // For each parameter, the name is separated from the corresponding value by an '=' character (ASCII code 61)
        // Each name-value pair is separated by an '&' character (ASCII code 38)
        return implode('&', $pairs);
    }
}
