<?php

/**
 * This is part of the email forward script to handle tweetlater keyword digest and twitter notification emails.
 *
 * @copyright (c) 2009 Marko Manninen <mmstud@gmail.com>
 */

class IncomingEmailParser 
{
	var $aEmailInfo;
	var $sEmailContent;
	
	/**
	 * Main constructor
	 *
	 * @access public
	 * @return void
	 */
	function IncomingEmailParser() {
		$this->sEmailContent = $this->_get_email_content();
		$this->aEmailInfo = $this->_get_email_info();
	}
	
	/**
	 * Call this method, if you want to get Twitter email headers parsed.
	 *
	 * @access public
	 * @return string
	 */
	function setup_twitter_info() {
		
		$this->aEmailInfo['twitter_sender_username'] = '';
		$this->aEmailInfo['twitter_receiver_username'] = '';
		$this->aEmailInfo['twitter_direct_message'] = '';
		$from = $this->aEmailInfo['from'];
		$headers = $this->aEmailInfo['headers'];
		$message = str_replace("=\n", '', $this->aEmailInfo['message']);
		
		# is message coming from twitter?
		if (is_integer(strpos($from, 'twitter'))) {
			# direct message
			if ($this->is_direct_message()) {
				preg_match_all('/X-Twittersenderscreenname: ([a-zA-Z0-9_].*)/', $headers, $match);
				$this->aEmailInfo['twitter_sender_username'] = strtolower($match[1][0]);
				
				preg_match_all('/X-Twittersendername: (.*)/', $headers, $match);
				$this->aEmailInfo['twitter_sender_name'] = $match[1][0];
				
				preg_match_all('/X-Twittersenderid: ([0-9].*)/', $headers, $match);
				$this->aEmailInfo['twitter_sender_id'] = $match[1][0];
				
				preg_match_all('/Sender: (.*)/', $headers, $match);
				$this->aEmailInfo['twitter_sender_email'] = str_replace(array('Twitter <twitter-dm-', '=', '@postmaster.twitter.com>'), array('', '@', ''), $match[1][0]);

				preg_match_all('/X-Twitterrecipientscreenname: ([a-zA-Z0-9_].*)/', $headers, $match);
				$this->aEmailInfo['twitter_receiver_username'] = strtolower($match[1][0]);
				
				preg_match_all('/X-Twitterrecipientname: (.*)/', $headers, $match);
				$this->aEmailInfo['twitter_receiver_name'] = $match[1][0];
				
				preg_match_all('/X-Twitterrecipientid: ([0-9].*)/', $headers, $match);
				$this->aEmailInfo['twitter_receiver_id'] = $match[1][0];
				
				$aMessage = split("\n", $message);
				$this->aEmailInfo['twitter_direct_message'] = $aMessage[6];
				
			} elseif ($this->is_follow_message()) {
				preg_match_all('/X-Twittersenderscreenname: ([a-zA-Z0-9_].*)/', $headers, $match);
				$this->aEmailInfo['twitter_sender_username'] = strtolower($match[1][0]);
				
				preg_match_all('/X-Twittersendername: (.*)/', $headers, $match);
				$this->aEmailInfo['twitter_sender_name'] = $match[1][0];
				
				preg_match_all('/X-Twittersenderid: ([0-9].*)/', $headers, $match);
				$this->aEmailInfo['twitter_sender_id'] = $match[1][0];
				
				preg_match_all('/X-Twitterrecipientscreenname: ([a-zA-Z0-9_].*)/', $headers, $match);
				$this->aEmailInfo['twitter_receiver_username'] = strtolower($match[1][0]);
				
				preg_match_all('/X-Twitterrecipientname: (.*)/', $headers, $match);
				$this->aEmailInfo['twitter_receiver_name'] = $match[1][0];
				
				preg_match_all('/X-Twitterrecipientid: ([0-9].*)/', $headers, $match);
				$this->aEmailInfo['twitter_receiver_id'] = $match[1][0];
			}
		}
		
	}
	
	function is_follow_message() {
		return is_integer(strpos($this->aEmailInfo['from'], 'twitter-follow-'));
	}

	function is_direct_message() {
		return is_integer(strpos($this->aEmailInfo['from'], 'twitter-dm-'));
	}

	/**
	 * Read data from stdin
	 *
	 * @access private
	 * @return string
	 */
	function _get_email_content() {
		$sEmail = '';
		$fd = fopen("php://stdin", "r");
		while (!feof($fd)) { $sEmail .= fread($fd, 1000000); }
		fclose($fd);
		return $sEmail;
	}
	/**
	 * Get email info in array format
	 *
	 * @access private
	 * @return array
	 */
	function _get_email_info() {
		$lines = explode("\n", $this->sEmailContent);
		$aEmailInfo['from'] = '';
		$aEmailInfo['to'] = '';
		$aEmailInfo['subject'] = '';
		$aEmailInfo['message'] = '';
		$aEmailInfo['headers'] = '';
		$splittingheaders = TRUE;
		
		for ($i=0; $i<count($lines); $i++) {
			if ($splittingheaders) {
				// this is a header
				$aEmailInfo['headers'] .= $lines[$i]."\n";
				// look out for special headers
				if (preg_match("/^Subject: (.*)/", $lines[$i], $matches)) {
					$aEmailInfo['subject'] = $matches[1];
				}
				if (preg_match("/^From: (.*)/", $lines[$i], $matches)) {
					$aEmailInfo['from'] = $matches[1];
				}
				if (preg_match("/^To: (.*)/", $lines[$i], $matches)) {
					$aEmailInfo['to'] = $matches[1];
				}
			} else {
				// not a header, but message
				$aEmailInfo['message'] .= $lines[$i]."\n";
			}
				if (trim($lines[$i])=="") {
				// empty line, header section has ended
				$splittingheaders = FALSE;
			}
		}
		return $aEmailInfo;
	}
	
	/**
	 * Checks if access to epipe is valid. Sender email and possible password
	 * are checked
	 *
	 * @param array $aEmailInfo
	 * @param string $sPassword
	 * @return boolean
	 */
	function is_valid_access($aAccessList, $sPassword = '') {
		// check sender
		if( !in_array( trim( $this->aEmailInfo['from'] ), $aAccessList ) ) {
			return false;
		}
		// Check password, if it is passed as argument
		// Password must be given on email subject line and compare with argument password!
		if( $sPassword != '' ) {
			$aSubject = explode( ' ', $this->aEmailInfo['subject'] );
			// compare last subject string to argument password
			return $aSubject[(count($aSubject)-1)] == $sPassword;
		}
		return true;
	}
}

?>