<?php
/********************************************************************************
* include/NetNNTP.inc.php : NNTP subroutines
* -------------------------
*
* This file is part of the banana distribution
* Copyright: See COPYING files that comes with this distribution
********************************************************************************/

/** Class NNTP
 *  implements some basic functions for NNTP protocol
 */
class nntp {
  /** socket filehandle */
  var $ns;
  /** debug mode */
  var $debug;
  /** posting allowed */
  var $posting;
  /** last NNTP error code */
  var $lasterrorcode;
  /** last NNTP error text */
  var $lasterrortext;

# Socket functions

  /** get a line from server
   * @return STRING 
   */

  function gline() {
    $line = preg_replace("/(\r|\n)/","",fgets($this->ns,1200));
    if ($this->debug) {
      print "NNTP >>>> $line \n";
    }
    return $line;
  }

  /** puts a line on server
   * @param STRING $_line line to put
   */
   
  function pline($_line) {
    if ($this->debug) {
      $dline = preg_replace("/\r\n$/","",$_line);
      $dline = preg_replace("/(\r|\n|\r\n)/","\nNNTP <<<< ",$dline);
      print "NNTP <<<< $dline \n";
    }
    return fputs($this->ns,$_line,strlen($_line));
  }
  
  /** constructor
   * @param $_host STRING NNTP host
   * @param $_timeout INTEGER socket timeout
   * @param $_debug BOOLEAN debug flag (generates verbose output if on)
   * @param $_reader BOOLEAN sends a "MODE READER" at connection if true
   */

  function nntp($_host,$_timeout=120,$_debug=0,$_reader=true) {
    if (preg_match("/([^:]+):([^:]+)/",$_host,$regs)) {
      $host = $regs[1];
      $port = $regs[2];
    } else {
      $host = $_host;
      $port = 119;
    }
    $this->ns = fsockopen($host, $port, $errno, $errstr, $_timeout);
    $this->debug = $_debug;
    if (!$this->ns) {
      if ($this->debug) {
        echo "ERREUR: $errno - $errstr <br />\n";
      }
      $this = false;
      return false;
    }
    $result = $this->gline(); 
    $this->posting = (substr($result,0,3)=="200");
    if ($_reader && (substr($result,0,1)=="2")) {
      $this->pline("MODE READER\r\n");
      $result = $this->gline();
      $this->posting = (substr($result,0,3)=="200");
    }
    return (substr($result,0,1)=="2");
  }

# strict NNTP Functions [RFC 977]
# see http://www.faqs.org/rfcs/rfc977.html

  /** authentification
   * @param $_user STRING login
   * @param $_pass INTEGER password
   * @return BOOLEAN true if authentication was successful
   */

  function authinfo($_user,$_pass) {
    $user = preg_replace("/(\r|\n)/","",$_user);
    $pass = preg_replace("/(\r|\n)/","",$_pass);
    $this->pline("AUTHINFO USER $user\r\n");
    $this->gline();
    $this->pline("AUTHINFO PASS $pass\r\n");
    $result=$this->gline();
    if (substr($result,0,1)!="2") {
      $this->lasterrorcode = substr($result,0,3);
      $this->lasterrortext = substr($result,4);
      return false;
    }
    return true;
  }

  /** retrieves an article
   * MSGID is a numeric ID a shown in article's headers. MSGNUM is a
   * server-dependent ID (see X-Ref on many servers) and retriving 
   * an article by this way will change the current article pointer.
   * If an error occur, false is returned. 
   * @param $_msgid STRING MSGID or MSGNUM of article
   * @return ARRAY lines of the article
   * @see body
   * @see head
   */

  function article($_msgid="") {
    $msgid = preg_replace("/(\r|\n)/","",$_msgid);
    $this->pline("ARTICLE $msgid\r\n");
    $result = $this->gline();
    if (substr($result,0,1)!="2") {
      $this->lasterrorcode = substr($result,0,3);
      $this->lasterrortext = substr($result,4);
      return false;
    }
    $result = $this->gline();
    while ($result != ".") {
      $array[] = $result;
      $result = $this->gline();
    }
    return $array;
  }

  /** post a message
   * if an error occur, false is returned
   * @param $_message STRING message to post
   * @return STRING MSGID of article 
   */

  function post($_message) {
    if (is_array($_message)) {
      $message=join("\n",$_message);
    } else {
      $message=$_message;
    }
    $this->pline("POST \r\n");
    $result=$this->gline();
    if (substr($result,0,1)!="3") {
      $this->lasterrorcode = substr($result,0,3);
      $this->lasterrortext = substr($result,4);
      return false;
    }
    $this->pline($message."\r\n.\r\n");
    $result = $this->gline();
    if (substr($result,0,1)!="2") {
      $this->lasterrorcode = substr($result,0,3);
      $this->lasterrortext = substr($result,4);
      return false;
    }
    if (substr($result,0,1)=="2") {
      if (preg_match("/(<[^@>]+@[^@>]+>)/",$result,$regs)) {
        return $regs[0];
      } else {
        return true;
      }
    }
    return false;
  }

  /** fetches the body of an article
   * params are the same as article
   * @param $_msgid STRING MSGID or MSGNUM of article
   * @return ARRAY lines of the article
   * @see article
   * @see head
   */
  
  function body($_msgid="") {
    $msgid = preg_replace("/(\r|\n)/","",$_msgid);
    $this->pline("BODY $msgid\r\n");
    $result = $this->gline();
    if (substr($result,0,1)!="2") {
      $this->lasterrorcode = substr($result,0,3);
      $this->lasterrortext = substr($result,4);
      return false;
    }
    $result = $this->gline();
    while ($result != ".") {
      $array[] = $result;
      $result = $this->gline();
    }
    return $array;
  }

  /** fetches the headers of an article
   * params are the same as article
   * @param $_msgid STRING MSGID or MSGNUM of article
   * @return ARRAY lines of the article
   * @see article
   * @see body
   */
  
  function head($_msgid="") {
    $msgid = preg_replace("/(\r|\n)/","",$_msgid);
    $this->pline("HEAD $msgid\r\n");
    $result = $this->gline();
    if (substr($result,0,1)!="2") {
      $this->lasterrorcode = substr($result,0,3);
      $this->lasterrortext = substr($result,4);
      return false;
    }
    $result = $this->gline();
    while ($result != ".") {
      $array[] = $result;
      $result = $this->gline();
    }
    return $array;
  }
  
  /** set current group
   * @param $_group STRING 
   * @return ARRAY array : nb of articles in group, MSGNUM of first article, MSGNUM of last article, and group name
   */
  
  function group($_group) {
    $group = preg_replace("/(\r|\n)/","",$_group);
    $this->pline("GROUP $group\r\n");
    $line = $this->gline();
    if (substr($line,0,1)!="2") {
      $this->lasterrorcode = substr($line,0,3);
      $this->lasterrortext = substr($line,4);
      return false;
    }
    if (preg_match("/^2\d{2} (\d+) (\d+) (\d+) ([^ ]+)/",
    $line,$regs)) {
      return array($regs[1],$regs[2],$regs[3],$regs[4]);
    }
    return $false;
  }

  /** set the article pointer to the previous article in current group
   * @return STRING MSGID of article
   * @see next
   */
  
  function last() {
    $this->pline("LAST \r\n");
    $line = $this->gline();
    if (substr($line,0,1)!="2") {
      $this->lasterrorcode = substr($result,0,3);
      $this->lasterrortext = substr($result,4);
      return false;
    }
    if (preg_match("/^2\d{2} \d+ <([^>]+)>/",$line,$regs)) {
      return "<{$regs[1]}>";
    }
    return $false;
  }
  
  /** set the article pointer to the next article in current group
   * @return STRING MSGID of article
   * @see last
   */
  
  function next() {
    $this->pline("NEXT \r\n");
    $line = $this->gline();
    if (substr($line,0,1)!="2") {
      $this->lasterrorcode = substr($result,0,3);
      $this->lasterrortext = substr($result,4);
      return false;
    }
    if (preg_match("/^2\d{2} \d+ <([^>]+)>/",$line,$regs)) {
      return "<{$regs[1]}>";
    }
    return $false;
  }

  /** set the current article pointer
   * @param $_msgid STRING MSGID or MSGNUM of article
   * @return BOOLEAN true if authentication was successful, error code otherwise
   * @see article
   * @see body
   */
  
  function nntpstat($_msgid) {
    $msgid = preg_replace("/(\r|\n)/","",$_msgid);
    $this->pline("STAT $msgid\r\n");
    $line = $this->gline();
    if (substr($line,0,1)!="2") {
      $this->lasterrorcode = substr($result,0,3);
      $this->lasterrortext = substr($result,4);
      return false;
    }
    if (preg_match("/^2\d{2} \d+ <([^>]+)>/",$line,$regs)) {
      return "<{$regs[1]}>";
    }
    return false;
  }
  
  /** returns true if posting is allowed
   * @return BOOLEAN true if posting is allowed lines 
   */
  
  function postok() {
    return ($this->posting);
  }

  /** gets information about all active newsgroups
   * @return ARRAY group name => (MSGNUM of first article, MSGNUM of last article, NNTP flags)
   * @see newgroups
   */
  
  function liste() {
    $this->pline("LIST\r\n");
    if (substr($this->gline(),0,1)!="2") return false;
    $result = $this->gline();
    while ($result != ".") {
      preg_match("/([^ ]+) (\d+) (\d+) (.)/",$result,$regs);
      $array[$regs[1]]=array(intval($regs[2]),intval($regs[3]),
        intval($regs[4]));
      $result = $this->gline();
    }
    return $array;
  }

  /** get information about recent newsgroups 
   * same as list, but information are limited to newgroups created after $_since
   * @param $_since INTEGER unix timestamp
   * @param $_distributions STRING distributions 
   * @return ARRAY same format as liste
   * @see liste
   */
  
  function newgroups($_since,$_distributions="") {
    #assume $_since is a unix timestamp
    $distributions = preg_replace("/(\r|\n)/","",$_distributions);
    $this->pline("NEWGROUPS ".gmdate("ymd His",$_since)
    ." GMT $distributions\r\n");
    if (substr($this->gline(),0,1)!="2") return false;
    $result = $this->gline();
    $array=array();
    while ($result != ".") {
      preg_match("/([^ ]+) (\d+) (\d+) (.)/",$result,$regs);
      $array[$regs[1]]=array(intval($regs[2]),intval($regs[3]),
        intval($regs[4]));
      $result = $this->gline();
    }
    return $array;
  }

  /** gets a list of new articles
   * @param $_since INTEGER unix timestamp
   * @parma $_groups STRING pattern of intersting groups 
   * @return ARRAY MSGID of new articles
   */
  
  function newnews($_since,$_groups="*",$_distributions="") {
    $distributions = preg_replace("/(\r|\n)/","",$_distributions);
    $groups = preg_replace("/(\r|\n)/","",$_groups);
    $array=array();
    #assume $since is a unix timestamp
    $this->pline("NEWNEWS $_groups ".gmdate("ymd His",$_since)
    ." GMT $distributions\r\n");
    if (substr($this->gline(),0,1)!="2") return false;
    $result = $this->gline();
    while ($result != ".") {
      $array[] =  $result;
      $result = $this->gline();
    }
    return $array;
  }

  /** Tell the remote server that I am not a user client, but probably another news server
   * @return BOOLEAN true if sucessful
   */
  
  function slave() {
    $this->pline("SLAVE \r\n");
    return (substr($this->gline(),0,1)=="2");
  }

  /** implements IHAVE method
   * @param $_msgid STRING MSGID of article
   * @param $_message STRING article
   * @return BOOLEAN 
   */
  
  function ihave($_msgid,$_message=false) {
    $msgid = preg_replace("/(\r|\n)/","",$_msgid);
    if (is_array($message)) 
	  $message=join("\n",$_message);
	else 
	  $message=$_message;
    $this->pline("IHAVE $msgid \r\n");
    $result=$this->gline();
    if ($message && (substr($result,0,1)=="3")) {
      $this->pline("$message\r\n.\r\n");
      $result=$this->gline();
    }
    return (substr($result,0,1)=="2");
  }

  /** closes connection to server
   */
  
  function quit() {
    $this->pline("QUIT\r\n");
    $this->gline();
    fclose($this->ns);
  }

# NNTP Extensions [RFC 2980]

  /** Returns the date on the remote server
   * @return INTEGER timestamp 
   */
  
  function date() {
    $this->pline("DATE \r\n");
    $result = $this->gline();
    if (preg_match("/^111 (\d{4})(\d{2})(\d{2})"
    ."(\d{2})(\d{2})(\d{2})$/",$result,$r)) {
      return gmmktime($r[4],$r[5],$r[6],$r[2],$r[3],$r[1]);
    }
    return false;
  }

  /** returns group descriptions
   * @param $_pattern STRING pattern of intersting groups
   * @return ARRAY group name => description
   */
  
  function xgtitle($_pattern="*") {
    $pattern = preg_replace("/(\r|\n)/","",$_pattern);
    $this->pline("XGTITLE $pattern \r\n");
    if (substr($this->gline(),0,1)!="2") return false;
    $result = $this->gline();
    while ($result != ".") {
      preg_match("/([^ \t]+)( |\t)+(.+)$/",$result,$regs);
      $array[$regs[1]]=$regs[3];
      $result = $this->gline();
    }
    return $array;
  }

  /** obtain the header field $hdr for all the messages specified
   * @param $_hdr STRING name of the header (eg: 'From')
   * @param $_range STRING range of articles 
   * @return ARRAY MSGNUM => header value
   */
  
  function xhdr($_hdr,$_range="") {
    $hdr = preg_replace("/(\r|\n)/","",$_hdr);
    $range = preg_replace("/(\r|\n)/","",$_range);
    $this->pline("XHDR $hdr $range \r\n");
    if (substr($this->gline(),0,1)!="2") return false;
    $result = $this->gline();
    $array=array();
    while ($result != ".") {
      preg_match("/([^ \t]+) (.*)$/",$result,$regs);
      $array[$regs[1]]=$regs[2];
      $result = $this->gline();
    }
    return $array;
  }

  /** obtain the header field $_hdr matching $_pat for all the messages specified
   * @param $_hdr STRING name of the header (eg: 'From')
   * @param $_range STRING range of articles 
   * @param $_pat STRING pattern
   * @return ARRAY MSGNUM => header value
   */
  
  function xpat($_hdr,$_range,$_pat) {
    $hdr = preg_replace("/(\r|\n)/","",$_hdr);
    $range = preg_replace("/(\r|\n)/","",$_range);
    $pat = preg_replace("/(\r|\n)/","",$_pat);
    $this->pline("XPAT $hdr $range $pat\r\n");
    if (substr($this->gline(),0,1)!="2") return false;
    $result = $this->gline();
    while ($result != ".") {
      preg_match("/([^ \t]+) (.*)$/",$result,$regs);
      $array[$regs[1]]=$regs[2];
      $result = $this->gline();
    }
    return $array;
  }
}

?>