/libraries/Facebook_oauth.php

<?php if (!defined('BASEPATH')) exit('No direct script access allowed'); 

/*
* Ezra Pool (ezra@servicecut.nl) http://servicecut.nl
*
* @author Ezra Pool
* @version 0.0.4
*
* Adapted Abraham Williams TwitterOAuth class for use with FacebookOAuth
*/

/**
 * Facebook OAuth 2 class
 */
class Facebook_oauth
{
	
	public $verifypeer 		= FALSE;	// Verify SSL Cert
	public $decode_JSON 	= TRUE;		// Decode returned json data
	public $connecttimeout 	= 30;		// Set connect timeout
	public $timeout 		= 30;		// Set timeout default.

	/* Set the useragent. */
	public $useragent = "FacebookOAuth v0.0.4 | http://github.com/Zae/FacebookOAuth";

	/* HTTP Proxy settings (will only take effect if you set 'behind_proxy' to true) */
	public $proxy_settings = array(
		'behind_proxy' => false,
		'host' => '',
		'port' => '',
		'user' => '',
		'pass' => '',
		'type' => CURLPROXY_HTTP,
		'auth' => CURLAUTH_BASIC
	);

	public $http_code;				// Contains the last HTTP status code returned.
	public $http_info = array();	// Contains the last HTTP headers returned.
	public $url;					// Contains the last API call.
	public $http_header = array();	// Contains last http_headers
	
	/* Variables used internally by the class and subclasses */
	protected $client_id, $client_secret, $access_token;
	protected $callback_url;
	
	protected static $METHOD_GET 	= "GET";
	protected static $METHOD_POST 	= "POST";
	protected static $METHOD_DELETE = "DELETE";
  
	/* Set API URLS */
	const AuthorizeUrl 		= 'https://graph.facebook.com/oauth/authorize';
	const AccessTokenUrl 	= 'https://graph.facebook.com/oauth/access_token';
	const GraphUrl 			= 'https://graph.facebook.com/';

	/* construct FacebookOAuth object */
	function __construct($facebook_config)
	{
		$this->client_id		= $facebook_config['client_id'];
		$this->client_secret	= $facebook_config['client_secret'];
		$this->callback_url		= $facebook_config['callback_url'];
		$this->access_token		= $facebook_config['access_token'];
	}
	
	/* Get the authorize URL @returns a string */
	public function getAuthorizeUrl($scope=NULL)
	{
		$params = array();
		$params["client_id"] = $this->client_id;
		
		if (!empty($this->callback_url))
		{
			$params["redirect_uri"] = $this->callback_url;
		}
		
		if (is_array($scope))
		{
			$params["scope"] = implode(",", $scope);
		}
		elseif ($scope != NULL)
		{
			$params["scope"] = $scope;
		}
		
		return self::AuthorizeUrl."?".OAuthUtils::build_http_query($params);
	}
  
	/* Exchange verify code for an access token @returns string access token */
	public function getAccessToken($code)
	{
		$params 					= array();
		$params["client_id"]		= $this->client_id;
		$params["client_secret"] 	= $this->client_secret;
		$params["code"] 			= $code;
		
		if (!empty($this->callback_url))
		{
			$params["redirect_uri"] = $this->callback_url;
		}
		
		$url		= self::AccessTokenUrl."?".OAuthUtils::build_http_query($params);
		$contents	= $this->http($url, self::$METHOD_GET);
		parse_str($contents, $output);

		if (array_key_exists('access_token', $output))
		{
			$this->access_token = $output['access_token'];
		}
		
		return $this->access_token;
	}
	
	public function getProfilePictureUrl($facebook_user_id)
  	{
  		$result = FALSE;
  		
  		// Makes sure server supports cURL request
		if ((ini_get('open_basedir') == '') && (ini_get('safe_mode') == 'Off' || !ini_get('safe_mode')))
		{
			$url 	 = 'http://graph.facebook.com/'.$facebook_user_id.'/picture?type=large';
			$options = array(
				CURLOPT_RETURNTRANSFER => 1,
				CURLOPT_FOLLOWLOCATION => 1
			);
		
			$ch = curl_init($url);
			curl_setopt_array($ch, $options);
			$output 	= curl_exec($ch);
			$download	= curl_getinfo($ch);
	
			if (preg_match('/static-ak/i', $download['url']))
  			{
				$result = FALSE;
  			}
  			else
  			{
  			  	$result = $download['url'];
  			}
  		}
  	
  		return $result;
  	}
  
	/* GET wrapper for http. */
	public function get($location, $fields=NULL, $introspection=FALSE)
	{
		$params = array();
		
		if (!empty($this->access_token))
		{
		  $params["access_token"] = $this->access_token;
		}
		
		if(!empty($fields))
		{
		  $params["fields"] = $fields;
		}
		
		if($introspection)
		{
		  $params["metadata"] = 1;
		}
		
		$url		= self::GraphUrl.OAuthUtils::urlencode_rfc3986($location)."?".OAuthUtils::build_http_query($params);
		$response	= $this->http($url, self::$METHOD_GET);
		
		return $this->decode_JSON ? json_decode($response) : $response;
	}
  
  	/* GET IDS wrapper for http. @ids comma separated list of ids */
	public function get_ids($ids)
	{
		$params = array();
		
		if(is_array($ids))
		{
		  $params["ids"] = implode(",", $ids);
		}
		else
		{
		  $params["ids"] = $ids;
		}
		
		if(!empty($this->access_token))
		{
		 	$params["access_token"] = $this->access_token;
		}
		
		$url 		= self::GraphUrl."?".OAuthUtils::build_http_query($params);
		$response 	= $this->http($url, self::$METHOD_GET);
		
		
		return $this->decode_JSON ? json_decode($response) : $response;
	}
  
	/* POST wrapper for http.*/
	public function post($location, $postfields = array())
	{
		$url = self::GraphUrl.OAuthUtils::urlencode_rfc3986($location);
		if(!empty($this->access_token))
		{
	  		$postfields["access_token"] = $this->access_token;
		}
		
		$response = $this->http($url, self::$METHOD_POST, $postfields);
		
		return $this->decode_JSON ? json_decode($response) : $response;
	}
	
	/* DELETE wrapper for http. */
	public function delete($location, $postfields = array())
	{
		$url = self::GraphUrl.OAuthUtils::urlencode_rfc3986($location);
		$postfields = array();
		
		if(!empty($this->access_token))
		{
	  		$postfields["access_token"] = $this->access_token;
		}
		
		$response = $this->http($url, self::$METHOD_DELETE, $postfields);
		return $this->decode_JSON ? json_decode($response) : $response;
	}

  /**
   * Make an HTTP request
   *
   * @return API results
   */
  private function http($url, $method="GET", $postfields=NULL)
  {
 	log_message('debug', 'the $url: '.$url);
  
    $this->http_info = array();
    $handle = curl_init();
    /* Curl settings */
    curl_setopt($handle, CURLOPT_HEADER, FALSE);
    curl_setopt($handle, CURLOPT_RETURNTRANSFER, TRUE);
    curl_setopt($handle, CURLOPT_HTTPHEADER, array('Expect:'));
    curl_setopt($handle, CURLOPT_SSL_VERIFYPEER, $this->verifypeer);
    curl_setopt($handle, CURLOPT_CONNECTTIMEOUT, $this->connecttimeout);
    curl_setopt($handle, CURLOPT_TIMEOUT, $this->timeout);
    curl_setopt($handle, CURLOPT_USERAGENT, $this->useragent);
    curl_setopt($handle, CURLOPT_HEADERFUNCTION, array($this, 'getHeader'));
    
    if ($this->proxy_settings['behind_proxy']){
      curl_setopt($ci, CURLOPT_PROXY, $this->proxy_settings['host']);
      curl_setopt($ci, CURLOPT_PROXYPORT, $this->proxy_settings['port']);
      curl_setopt($ci, CURLOPT_PROXYUSERPWD, "{$this->proxy_settings['user']}:{$this->proxy_settings['pass']}");
      curl_setopt($ci, CURLOPT_PROXYTYPE, $this->proxy_settings['type']);
      curl_setopt($ci, CURLOPT_PROXYAUTH, $this->proxy_settings['auth']);
    }
    
    switch($method){
      case self::$METHOD_POST:
        curl_setopt($handle, CURLOPT_POST, TRUE);
        if (!empty($postfields)) {
          curl_setopt($handle, CURLOPT_POSTFIELDS, $postfields);
        }
        break;
      case self::$METHOD_DELETE:
        curl_setopt($handle, CURLOPT_CUSTOMREQUEST, 'DELETE');
        if (!empty($postfields)){
          $url .= "?".OAuthUtils::build_http_query($postfields);
        }
        break;
    }
    curl_setopt($handle, CURLOPT_URL, $url);
    $response = curl_exec($handle);
    $this->http_code = curl_getinfo($handle, CURLINFO_HTTP_CODE);
    $this->http_info = array_merge($this->http_info, curl_getinfo($handle));
    $this->url = $url;
    curl_close($handle);
    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);
  }
}

/**
 *  OAuthUtils
 *  Copied and adapted from http://oauth.googlecode.com/svn/code/php/
 */
class OAuthUtils {
  public static function urlencode_rfc3986($input) {
    if (is_array($input)) {
      return array_map(array('OAuthUtils', 'urlencode_rfc3986'), $input);
    } else if (is_scalar($input)) {
      return str_replace(
        '+',
        ' ',
        str_replace('%7E', '~', rawurlencode($input))
      );
    } else {
      return '';
    }
  }
  public static function build_http_query($params) {
    if (!$params) return '';
    // Urlencode both keys and values
    $keys = OAuthUtils::urlencode_rfc3986(array_keys($params));
    $values = OAuthUtils::urlencode_rfc3986(array_values($params));
    $params = array_combine($keys, $values);
    
    $pairs = array();
    foreach ($params as $parameter => $value) {
      if (is_array($value)) {
        foreach ($value as $duplicate_value) {
          $pairs[] = $parameter . '=' . $duplicate_value;
        }
      } else {
        $pairs[] = $parameter . '=' . $value;
      }
    }
    // For each parameter, the name is separated from the corresponding value by an '=' character (ASCII code 61)
    // Each name-value pair is separated by an '&' character (ASCII code 38)
    return implode('&', $pairs);
  }
}