<?php

/*
 * Abraham Williams (abraham@abrah.am) http://abrah.am
 *
 * The first PHP Library to support OAuth for Twitter's REST API.
 */

/* Load OAuth lib. You can find it at http://oauth.net */
require_once( 'OAuth.php' );

/**
 * Twitter OAuth class
 */
class TwitterOAuth {
	/* Contains the last HTTP status code returned. */
	public $http_code;
	/* Contains the last API call. */
	public $url;
	/* Set up the API root URL. */
	public $host = 'https://api.twitter.com/1.1/';
	/* Set timeout default. */
	public $timeout = 30;
	/* Set connect timeout. */
	public $connecttimeout = 30;
	/* Verify SSL Cert. */
	public $ssl_verifypeer = false;
	/* Respons format. */
	public $format = 'json';
	/* Decode returned json data. */
	public $decode_json = true;
	/* Contains the last HTTP headers returned. */
	public $http_info;
	/* Set the useragnet. */
	public $useragent = 'TwitterOAuth v0.2.0-beta2';
	/* Immediately retry the API call if the response was not successful. */
	//public $retry = TRUE;




	/**
   * Set API URLS
   */
	function accessTokenURL() {
		return 'https://api.twitter.com/oauth/access_token'; }
	function authenticateURL() {
		return 'https://api.twitter.com/oauth/authenticate'; }
	function authorizeURL() {
		return 'https://api.twitter.com/oauth/authorize'; }
	function requestTokenURL() {
		return 'https://api.twitter.com/oauth/request_token'; }

	/**
   * Debug helpers
   */
	function lastStatusCode() {
		return $this->http_status; }
	function lastAPICall() {
		return $this->last_api_call; }

	/**
   * construct TwitterOAuth object
   */
	function __construct( $consumer_key, $consumer_secret, $oauth_token = null, $oauth_token_secret = null ) {
		$this->sha1_method = new OAuthSignatureMethod_HMAC_SHA1();
		$this->consumer    = new OAuthConsumer( $consumer_key, $consumer_secret );
		if ( ! empty( $oauth_token ) && ! empty( $oauth_token_secret ) ) {
			$this->token = new OAuthConsumer( $oauth_token, $oauth_token_secret );
		} else {
			$this->token = null;
		}
	}


	/**
   * Get a request_token from Twitter
   *
   * @returns a key/value array containing oauth_token and oauth_token_secret
   */
	function getRequestToken( $oauth_callback ) {
		$parameters                   = array();
		$parameters['oauth_callback'] = $oauth_callback;
		$request                      = $this->oAuthRequest( $this->requestTokenURL(), 'GET', $parameters );
		$token                        = OAuthUtil::parse_parameters( $request );
		$this->token                  = new OAuthConsumer( $token['oauth_token'], $token['oauth_token_secret'] );
		return $token;
	}

	/**
   * Get the authorize URL
   *
   * @returns a string
   */
	function getAuthorizeURL( $token, $sign_in_with_twitter = true ) {
		if ( is_array( $token ) ) {
			$token = $token['oauth_token'];
		}
		if ( empty( $sign_in_with_twitter ) ) {
			return $this->authorizeURL() . "?oauth_token={$token}";
		} else {
			 return $this->authenticateURL() . "?oauth_token={$token}";
		}
	}

	/**
   * Exchange request token and secret for an access token and
   * secret, to sign API calls.
   *
   * @returns array("oauth_token" => "the-access-token",
   *                "oauth_token_secret" => "the-access-secret",
   *                "user_id" => "9436992",
   *                "screen_name" => "abraham")
   */
	function getAccessToken( $oauth_verifier ) {
		$parameters                   = array();
		$parameters['oauth_verifier'] = $oauth_verifier;
		$request                      = $this->oAuthRequest( $this->accessTokenURL(), 'GET', $parameters );
		$token                        = OAuthUtil::parse_parameters( $request );
		$this->token                  = new OAuthConsumer( $token['oauth_token'], $token['oauth_token_secret'] );
		return $token;
	}

	/**
   * One time exchange of username and password for access token and secret.
   *
   * @returns array("oauth_token" => "the-access-token",
   *                "oauth_token_secret" => "the-access-secret",
   *                "user_id" => "9436992",
   *                "screen_name" => "abraham",
   *                "x_auth_expires" => "0")
   */
	function getXAuthToken( $username, $password ) {
		$parameters                    = array();
		$parameters['x_auth_username'] = $username;
		$parameters['x_auth_password'] = $password;
		$parameters['x_auth_mode']     = 'client_auth';
		$request                       = $this->oAuthRequest( $this->accessTokenURL(), 'POST', $parameters );
		$token                         = OAuthUtil::parse_parameters( $request );
		$this->token                   = new OAuthConsumer( $token['oauth_token'], $token['oauth_token_secret'] );
		return $token;
	}

	/**
   * GET wrapper for oAuthRequest.
   */
	function get( $url, $parameters = array() ) {
		$response = $this->oAuthRequest( $url, 'GET', $parameters );
		if ( $this->format === 'json' && $this->decode_json ) {
			return json_decode( $response );
		}
		return $response;
	}

	/**
   * POST wrapper for oAuthRequest.
   */
	function post( $url, $parameters = array() ) {
		$response = $this->oAuthRequest( $url, 'POST', $parameters );
		if ( $this->format === 'json' && $this->decode_json ) {
			return json_decode( $response );
		}
		return $response;
	}

	/**
   * DELETE wrapper for oAuthReqeust.
   */
	function delete( $url, $parameters = array() ) {
		$response = $this->oAuthRequest( $url, 'DELETE', $parameters );
		if ( $this->format === 'json' && $this->decode_json ) {
			return json_decode( $response );
		}
		return $response;
	}

	/**
   * Format and sign an OAuth / API request
   */
	function oAuthRequest( $url, $method, $parameters ) {
		if ( strrpos( $url, 'https://' ) !== 0 && strrpos( $url, 'http://' ) !== 0 ) {
			$url = "{$this->host}{$url}.{$this->format}";
		}
		$request = OAuthRequest::from_consumer_and_token( $this->consumer, $this->token, $method, $url, $parameters );
		$request->sign_request( $this->sha1_method, $this->consumer, $this->token );
		switch ( $method ) {
			case 'GET':
				return $this->http( $request->to_url(), 'GET' );
			default:
				return $this->http( $request->get_normalized_http_url(), $method, $request->to_postdata() );
		}
	}

	/**
   * Make an HTTP request
   *
   * @return API results
   */
	function http( $url, $method, $postfields = null ) {
		$this->http_info = array();
		$ci              = curl_init();
		/* Curl settings */
		curl_setopt( $ci, CURLOPT_USERAGENT, $this->useragent );
		curl_setopt( $ci, CURLOPT_CONNECTTIMEOUT, $this->connecttimeout );
		curl_setopt( $ci, CURLOPT_TIMEOUT, $this->timeout );
		curl_setopt( $ci, CURLOPT_RETURNTRANSFER, true );
		curl_setopt( $ci, CURLOPT_HTTPHEADER, array( 'Expect:' ) );
		curl_setopt( $ci, CURLOPT_SSL_VERIFYPEER, $this->ssl_verifypeer );
		curl_setopt( $ci, CURLOPT_HEADERFUNCTION, array( $this, 'getHeader' ) );
		curl_setopt( $ci, CURLOPT_HEADER, false );

		switch ( $method ) {
			case 'POST':
				curl_setopt( $ci, CURLOPT_POST, true );
				if ( ! empty( $postfields ) ) {
					curl_setopt( $ci, CURLOPT_POSTFIELDS, $postfields );
				}
				break;
			case 'DELETE':
				curl_setopt( $ci, CURLOPT_CUSTOMREQUEST, 'DELETE' );
				if ( ! empty( $postfields ) ) {
					$url = "{$url}?{$postfields}";
				}
		}

		curl_setopt( $ci, CURLOPT_URL, $url );
		$response        = curl_exec( $ci );
		$this->http_code = curl_getinfo( $ci, CURLINFO_HTTP_CODE );
		$this->http_info = array_merge( $this->http_info, curl_getinfo( $ci ) );
		$this->url       = $url;
		curl_close( $ci );
		return $response;
	}

	/**
   * Get the header info to store.
   */
	function getHeader( $ch, $header ) {
		$i = strpos( $header, ':' );
		if ( ! empty( $i ) ) {
			$key                       = str_replace( '-', '_', strtolower( substr( $header, 0, $i ) ) );
			$value                     = trim( substr( $header, $i + 2 ) );
			$this->http_header[ $key ] = $value;
		}
		return strlen( $header );
	}
}