<?php namespace Ejimba\Pesapal\OAuth;

class OAuthRequest {
	
	private $parameters;
	private $http_method;
	private $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 or $parameters = array();
		$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 = 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);

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