<?php
/**
 * Created by PhpStorm.
 * User: mxgel
 * Date: 11/14/16
 * Time: 2:31 AM
 */

namespace Knox\Pesapal\OAuth;

use Knox\Pesapal\OAuth\Exceptions\OAuthException;


/**
 * Class OAuthRequest
 *
 * @package Knox\Pesapal\OAuth
 */
class OAuthRequest
{
    /**
     * @var array|null
     */
    private $parameters;
    /**
     * @var
     */
    private $http_method;
    /**
     * @var
     */
    private $http_url;
    // for debug purposes
    /**
     * @var
     */
    public $base_string;
    /**
     * @var string
     */
    public static $version = '1.0';
    /**
     * @var string
     */
    public static $POST_INPUT = 'php://input';

    /**
     * OAuthRequest constructor.
     *
     * @param      $http_method
     * @param      $http_url
     * @param null $parameters
     */
    function __construct($http_method, $http_url, $parameters = NULL)
    {
        @$parameters or $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 or $http_url = $scheme .
            '://' . $_SERVER['HTTP_HOST'] .
            ':' .
            $_SERVER['SERVER_PORT'] .
            $_SERVER['REQUEST_URI'];
        @$http_method or $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 ($http_method == "POST"
                && @strstr($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 (@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 or $parameters = [];
        $defaults = [
            "oauth_version" => OAuthRequest::$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);
    }

    /**
     * @param      $name
     * @param      $value
     * @param bool $allow_duplicates
     */
    public function set_parameter($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] = [$this->parameters[$name]];
            }

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

    /**
     * @param $name
     *
     * @return mixed|null
     */
    public function get_parameter($name)
    {
        return isset($this->parameters[$name]) ? $this->parameters[$name] : null;
    }

    /**
     * @return array|null
     */
    public function get_parameters()
    {
        return $this->parameters;
    }

    /**
     * @param $name
     */
    public function unset_parameter($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 = [
            $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);
        if (array_key_exists('port', $parts)) {
            $port = @$parts['port'];
        } else {
            $port = false;
        }
        $scheme = $parts['scheme'];
        $host = $parts['host'];
        $path = @$parts['path'];

        $port or $port = ($scheme == 'https') ? '443' : '80';

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

        return $out;
    }

    /**
     * @return string
     */
    public function __toString()
    {
        return $this->to_url();
    }


    /**
     * @param $signature_method
     * @param $consumer
     * @param $token
     */
    public function sign_request($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);
    }

    /**
     * @param $signature_method
     * @param $consumer
     * @param $token
     *
     * @return mixed
     */
    public function build_signature($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_srand((double)microtime() * 10000);//optional for php 4.2.0 and up.
        $charid = strtoupper(md5(uniqid(rand(), true)));
        $hyphen = chr(45);// "-"
        $uuid = chr(123)// "{"
            . substr($charid, 0, 8) . $hyphen
            . substr($charid, 8, 4) . $hyphen
            . substr($charid, 12, 4) . $hyphen
            . substr($charid, 16, 4) . $hyphen
            . substr($charid, 20, 12)
            . chr(125);// "}"
        return $uuid;
    }
}