<?php

/*
Copyright (c) 2009 Abraham Williams - http://abrah.am - abraham@poseurte.ch
 
Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation
files (the "Software"), to deal in the Software without
restriction, including without limitation the rights to use,
copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the
Software is furnished to do so, subject to the following
conditions:
 
The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.
 
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES
OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
OTHER DEALINGS IN THE SOFTWARE.

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/";
  /* 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://twitter.com/oauth/authenticate'; }
  function authorizeURL()    { return 'https://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 = NULL) {
    $parameters = array();
    if (!empty($oauth_callback)) {
      $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 = FALSE) {
    $parameters = array();
    if (!empty($oauth_verifier)) {
      $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);
  }
}
