<?php

require_once __DIR__ . '/OAuthException.php';
require_once __DIR__ . '/OAuthUtil.php';

class OAuthRequest {
    protected $parameters;
    protected $http_method;
    protected $http_url;
    // for debug purposes
    public $base_string;
    public static $version = '1.0';
    public static $POST_INPUT = 'php://input';

    function __construct($http_method, $http_url, $parameters=NULL) {
        $parameters = ($parameters) ? $parameters : array();
        $parameters = array_merge( OAuthUtil::parse_parameters(parse_url($http_url, PHP_URL_QUERY)), $parameters);
        $this->parameters = $parameters;
        $this->http_method = $http_method;
        $this->http_url = $http_url;
    }


    /**
     * attempt to build up a request from what was passed to the server
     */
    public static function from_request($http_method=NULL, $http_url=NULL, $parameters=NULL) {
        $scheme = (!isset($_SERVER['HTTPS']) || $_SERVER['HTTPS'] != "on")
            ? 'http'
            : 'https';
        $http_url = ($http_url) ? $http_url : $scheme .
            '://' . $_SERVER['SERVER_NAME'] .
            ':' .
            $_SERVER['SERVER_PORT'] .
            $_SERVER['REQUEST_URI'];
        $http_method = ($http_method) ? $http_method : $_SERVER['REQUEST_METHOD'];

        // We weren't handed any parameters, so let's find the ones relevant to
        // this request.
        // If you run XML-RPC or similar you should use this to provide your own
        // parsed parameter-list
        if (!$parameters) {
            // Find request headers
            $request_headers = OAuthUtil::get_headers();

            // Parse the query-string to find GET parameters
            $parameters = OAuthUtil::parse_parameters($_SERVER['QUERY_STRING']);

            // It's a POST request of the proper content-type, so parse POST
            // parameters and add those overriding any duplicates from GET
            if ($http_method == "POST"
                &&  isset($request_headers['Content-Type'])
                && strstr($request_headers['Content-Type'],
                          'application/x-www-form-urlencoded')
               ) {
                $post_data = OAuthUtil::parse_parameters(
                                                         file_get_contents(self::$POST_INPUT)
                                                        );
                $parameters = array_merge($parameters, $post_data);
            }

            // We have a Authorization-header with OAuth data. Parse the header
            // and add those overriding any duplicates from GET or POST
            if (isset($request_headers['Authorization']) && substr($request_headers['Authorization'], 0, 6) == 'OAuth ') {
                $header_parameters = OAuthUtil::split_header(
                                                             $request_headers['Authorization']
                                                            );
                $parameters = array_merge($parameters, $header_parameters);
            }

        }

        return new OAuthRequest($http_method, $http_url, $parameters);
    }

    /**
     * pretty much a helper function to set up the request
     */
    public static function from_consumer_and_token($consumer, $token, $http_method, $http_url, $parameters=NULL) {
        $parameters = ($parameters) ?  $parameters : array();
        $defaults = array("oauth_version" => OAuthRequest::$version,
                          "oauth_nonce" => OAuthRequest::generate_nonce(),
                          "oauth_timestamp" => OAuthRequest::generate_timestamp(),
                          "oauth_consumer_key" => $consumer->key);
        if ($token)
            $defaults['oauth_token'] = $token->key;

        $parameters = array_merge($defaults, $parameters);

        return new OAuthRequest($http_method, $http_url, $parameters);
    }

    public function set_parameter($name, $value, $allow_duplicates = true) {
        if ($allow_duplicates && isset($this->parameters[$name])) {
            // We have already added parameter(s) with this name, so add to the list
            if (is_scalar($this->parameters[$name])) {
                // This is the first duplicate, so transform scalar (string)
                // into an array so we can add the duplicates
                $this->parameters[$name] = array($this->parameters[$name]);
            }

            $this->parameters[$name][] = $value;
        } else {
            $this->parameters[$name] = $value;
        }
    }

    public function get_parameter($name) {
        return isset($this->parameters[$name]) ? $this->parameters[$name] : null;
    }

    public function get_parameters() {
        return $this->parameters;
    }

    public function unset_parameter($name) {
        unset($this->parameters[$name]);
    }

    /**
     * The request parameters, sorted and concatenated into a normalized string.
     * @return string
     */
    public function get_signable_parameters() {
        // Grab all parameters
        $params = $this->parameters;

        // Remove oauth_signature if present
        // Ref: Spec: 9.1.1 ("The oauth_signature parameter MUST be excluded.")
        if (isset($params['oauth_signature'])) {
            unset($params['oauth_signature']);
        }

        return OAuthUtil::build_http_query($params);
    }

    /**
     * Returns the base string of this request
     *
     * The base string defined as the method, the url
     * and the parameters (normalized), each urlencoded
     * and the concated with &.
     */
    public function get_signature_base_string() {
        $parts = array(
                       $this->get_normalized_http_method(),
                       $this->get_normalized_http_url(),
                       $this->get_signable_parameters()
                      );

        $parts = OAuthUtil::urlencode_rfc3986($parts);

        return implode('&', $parts);
    }

    /**
     * just uppercases the http method
     */
    public function get_normalized_http_method() {
        return strtoupper($this->http_method);
    }

    /**
     * parses the url and rebuilds it to be
     * scheme://host/path
     */
    public function get_normalized_http_url() {
        $parts = parse_url($this->http_url);

        $scheme = (isset($parts['scheme'])) ? $parts['scheme'] : 'http';
        $port = (isset($parts['port'])) ? $parts['port'] : (($scheme == 'https') ? '443' : '80');
        $host = (isset($parts['host'])) ? strtolower($parts['host']) : '';
        $path = (isset($parts['path'])) ? $parts['path'] : '';

        if (($scheme == 'https' && $port != '443')
            || ($scheme == 'http' && $port != '80')) {
            $host = "$host:$port";
        }
        return "$scheme://$host$path";
    }

    /**
     * builds a url usable for a GET request
     */
    public function to_url() {
        $post_data = $this->to_postdata();
        $out = $this->get_normalized_http_url();
        if ($post_data) {
            $out .= '?'.$post_data;
        }
        return $out;
    }

    /**
     * builds the data one would send in a POST request
     */
    public function to_postdata() {
        return OAuthUtil::build_http_query($this->parameters);
    }

    /**
     * builds the Authorization: header
     */
    public function to_header($realm=null) {
        $first = true;
        if($realm) {
            $out = 'Authorization: OAuth realm="' . OAuthUtil::urlencode_rfc3986($realm) . '"';
            $first = false;
        } else
            $out = 'Authorization: OAuth';

        $total = array();
        foreach ($this->parameters as $k => $v) {
            if (substr($k, 0, 5) != "oauth") continue;
            if (is_array($v)) {
                throw new OAuthException('Arrays not supported in headers');
            }
            $out .= ($first) ? ' ' : ',';
            $out .= OAuthUtil::urlencode_rfc3986($k) .
                '="' .
                OAuthUtil::urlencode_rfc3986($v) .
                '"';
            $first = false;
        }
        return $out;
    }

    public function __toString() {
        return $this->to_url();
    }


    public function sign_request($signature_method, $consumer, $token) {
        $this->set_parameter(
                             "oauth_signature_method",
                             $signature_method->get_name(),
                             false
                            );
        $signature = $this->build_signature($signature_method, $consumer, $token);
        $this->set_parameter("oauth_signature", $signature, false);
    }

    public function build_signature($signature_method, $consumer, $token) {
        $signature = $signature_method->build_signature($this, $consumer, $token);
        return $signature;
    }

    /**
     * util function: current timestamp
     */
    private static function generate_timestamp() {
        return time();
    }

    /**
     * util function: current nonce
     */
    private static function generate_nonce() {
        $mt = microtime();
        $rand = mt_rand();

        return md5($mt . $rand); // md5s look nicer than numbers
    }
}