<?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://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, true );
		}
		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, true );
		}
		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 ,true);
		}
		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 );
	}
}
