<?php
/*~ class.pop3.php
.---------------------------------------------------------------------------.
|  Software: PHPMailer - PHP email class                                    |
|   Version: 5.2.6                                                          |
|      Site: https://github.com/PHPMailer/PHPMailer/                        |
| ------------------------------------------------------------------------- |
|    Admins: Marcus Bointon                                                 |
|    Admins: Jim Jagielski                                                  |
|   Authors: Andy Prevost (codeworxtech) codeworxtech@users.sourceforge.net |
|          : Marcus Bointon (coolbru) coolbru@users.sourceforge.net         |
|          : Jim Jagielski (jimjag) jimjag@gmail.com                        |
|   Founder: Brent R. Matzelle (original founder)                           |
| Copyright (c) 2010-2012, Jim Jagielski. All Rights Reserved.              |
| Copyright (c) 2004-2009, Andy Prevost. All Rights Reserved.               |
| Copyright (c) 2001-2003, Brent R. Matzelle                                |
| ------------------------------------------------------------------------- |
|   License: Distributed under the Lesser General Public License (LGPL)     |
|            http://www.gnu.org/copyleft/lesser.html                        |
| This program is distributed in the hope that it will be useful - WITHOUT  |
| ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or     |
| FITNESS FOR A PARTICULAR PURPOSE.                                         |
'---------------------------------------------------------------------------'
*/

/**
 * PHPMailer - PHP POP Before SMTP Authentication Class
 * NOTE: Designed for use with PHP version 5 and up
 * @package PHPMailer
 * @author Andy Prevost
 * @author Marcus Bointon
 * @author Jim Jagielski
 * @copyright 2010 - 2012 Jim Jagielski
 * @copyright 2004 - 2009 Andy Prevost
 * @license http://www.gnu.org/copyleft/lesser.html Distributed under the Lesser General Public License (LGPL)
 */

/**
 * PHP POP-Before-SMTP Authentication Class
 *
 * Version 5.2.6
 *
 * @license: LGPL, see PHPMailer License
 *
 * Specifically for PHPMailer to allow POP before SMTP authentication.
 * Does not yet work with APOP - if you have an APOP account, contact Jim Jagielski
 * and we can test changes to this script.
 *
 * This class is based on the structure of the SMTP class originally authored by Chris Ryan
 *
 * This class is rfc 1939 compliant and implements all the commands
 * required for POP3 connection, authentication and disconnection.
 *
 * @package PHPMailer
 * @author Richard Davey (orig) <rich@corephp.co.uk>
 * @author Andy Prevost
 * @author Jim Jagielski
 */

class POP3 {
  /**
   * Default POP3 port
   * @var int
   */
  public $POP3_PORT = 110;

  /**
   * Default Timeout
   * @var int
   */
  public $POP3_TIMEOUT = 30;

  /**
   * POP3 Carriage Return + Line Feed
   * @var string
   */
  public $CRLF = "\r\n";

  /**
   * Displaying Debug warnings? (0 = now, 1+ = yes)
   * @var int
   */
  public $do_debug = 2;

  /**
   * POP3 Mail Server
   * @var string
   */
  public $host;

  /**
   * POP3 Port
   * @var int
   */
  public $port;

  /**
   * POP3 Timeout Value
   * @var int
   */
  public $tval;

  /**
   * POP3 Username
   * @var string
   */
  public $username;

  /**
   * POP3 Password
   * @var string
   */
  public $password;

  /**
   * Sets the POP3 PHPMailer Version number
   * @var string
   */
  public $Version         = '5.2.6';

  /////////////////////////////////////////////////
  // PROPERTIES, PRIVATE AND PROTECTED
  /////////////////////////////////////////////////

  /**
   * @var resource Resource handle for the POP connection socket
   */
  private $pop_conn;
  /**
   * @var boolean Are we connected?
   */
  private $connected;
  /**
   * @var array Error container
   */
  private $error;     //  Error log array

  /**
   * Constructor, sets the initial values
   * @access public
   * @return POP3
   */
  public function __construct() {
    $this->pop_conn  = 0;
    $this->connected = false;
    $this->error     = null;
  }

  /**
   * Combination of public events - connect, login, disconnect
   * @access public
   * @param string $host
   * @param bool|int $port
   * @param bool|int $tval
   * @param string $username
   * @param string $password
   * @param int $debug_level
   * @return bool
   */
  public function Authorise ($host, $port = false, $tval = false, $username, $password, $debug_level = 0) {
    $this->host = $host;

    //  If no port value is passed, retrieve it
    if ($port == false) {
      $this->port = $this->POP3_PORT;
    } else {
      $this->port = $port;
    }

    //  If no port value is passed, retrieve it
    if ($tval == false) {
      $this->tval = $this->POP3_TIMEOUT;
    } else {
      $this->tval = $tval;
    }

    $this->do_debug = $debug_level;
    $this->username = $username;
    $this->password = $password;

    //  Refresh the error log
    $this->error = null;

    //  Connect
    $result = $this->Connect($this->host, $this->port, $this->tval);

    if ($result) {
      $login_result = $this->Login($this->username, $this->password);

      if ($login_result) {
        $this->Disconnect();

        return true;
      }

    }

    //  We need to disconnect regardless if the login succeeded
    $this->Disconnect();

    return false;
  }

  /**
   * Connect to the POP3 server
   * @access public
   * @param string $host
   * @param bool|int $port
   * @param integer $tval
   * @return boolean
   */
  public function Connect ($host, $port = false, $tval = 30) {
    //  Are we already connected?
    if ($this->connected) {
      return true;
    }

    /*
    On Windows this will raise a PHP Warning error if the hostname doesn't exist.
    Rather than suppress it with @fsockopen, let's capture it cleanly instead
    */

    set_error_handler(array(&$this, 'catchWarning'));

    //  Connect to the POP3 server
    $this->pop_conn = fsockopen($host,    //  POP3 Host
                  $port,    //  Port #
                  $errno,   //  Error Number
                  $errstr,  //  Error Message
                  $tval);   //  Timeout (seconds)

    //  Restore the error handler
    restore_error_handler();

    //  Does the Error Log now contain anything?
    if ($this->error && $this->do_debug >= 1) {
      $this->displayErrors();
    }

    //  Did we connect?
    if ($this->pop_conn == false) {
      //  It would appear not...
      $this->error = array(
        'error' => "Failed to connect to server $host on port $port",
        'errno' => $errno,
        'errstr' => $errstr
      );

      if ($this->do_debug >= 1) {
        $this->displayErrors();
      }

      return false;
    }

    //  Increase the stream time-out

    //  Check for PHP 4.3.0 or later
    if (version_compare(phpversion(), '5.0.0', 'ge')) {
      stream_set_timeout($this->pop_conn, $tval, 0);
    } else {
      //  Does not work on Windows
      if (substr(PHP_OS, 0, 3) !== 'WIN') {
        socket_set_timeout($this->pop_conn, $tval, 0);
      }
    }

    //  Get the POP3 server response
    $pop3_response = $this->getResponse();

    //  Check for the +OK
    if ($this->checkResponse($pop3_response)) {
      //  The connection is established and the POP3 server is talking
      $this->connected = true;
      return true;
    }
    return false;
  }

  /**
   * Login to the POP3 server (does not support APOP yet)
   * @access public
   * @param string $username
   * @param string $password
   * @return boolean
   */
  public function Login ($username = '', $password = '') {
    if ($this->connected == false) {
      $this->error = 'Not connected to POP3 server';

      if ($this->do_debug >= 1) {
        $this->displayErrors();
      }
    }

    if (empty($username)) {
      $username = $this->username;
    }

    if (empty($password)) {
      $password = $this->password;
    }

    $pop_username = "USER $username" . $this->CRLF;
    $pop_password = "PASS $password" . $this->CRLF;

    //  Send the Username
    $this->sendString($pop_username);
    $pop3_response = $this->getResponse();

    if ($this->checkResponse($pop3_response)) {
      //  Send the Password
      $this->sendString($pop_password);
      $pop3_response = $this->getResponse();

      if ($this->checkResponse($pop3_response)) {
        return true;
      }
    }
    return false;
  }

  /**
   * Disconnect from the POP3 server
   * @access public
   */
  public function Disconnect () {
    $this->sendString('QUIT');

    fclose($this->pop_conn);
  }

  /////////////////////////////////////////////////
  //  Private Methods
  /////////////////////////////////////////////////

  /**
   * Get the socket response back.
   * $size is the maximum number of bytes to retrieve
   * @access private
   * @param integer $size
   * @return string
   */
  private function getResponse ($size = 128) {
    $pop3_response = fgets($this->pop_conn, $size);

    return $pop3_response;
  }

  /**
   * Send a string down the open socket connection to the POP3 server
   * @access private
   * @param string $string
   * @return integer
   */
  private function sendString ($string) {
    $bytes_sent = fwrite($this->pop_conn, $string, strlen($string));

    return $bytes_sent;
  }

  /**
   * Checks the POP3 server response for +OK or -ERR
   * @access private
   * @param string $string
   * @return boolean
   */
  private function checkResponse ($string) {
    if (substr($string, 0, 3) !== '+OK') {
      $this->error = array(
        'error' => "Server reported an error: $string",
        'errno' => 0,
        'errstr' => ''
      );

      if ($this->do_debug >= 1) {
        $this->displayErrors();
      }

      return false;
    } else {
      return true;
    }

  }

  /**
   * If debug is enabled, display the error message array
   * @access private
   */
  private function displayErrors () {
    echo '<pre>';

    foreach ($this->error as $single_error) {
      print_r($single_error);
    }

    echo '</pre>';
  }

  /**
   * Takes over from PHP for the socket warning handler
   * @access private
   * @param integer $errno
   * @param string $errstr
   * @param string $errfile
   * @param integer $errline
   */
  private function catchWarning ($errno, $errstr, $errfile, $errline) {
    $this->error[] = array(
      'error' => "Connecting to the POP3 server raised a PHP warning: ",
      'errno' => $errno,
      'errstr' => $errstr
    );
  }

  //  End of class
}