<?php
/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this file,
 * You can obtain one at http://mozilla.org/MPL/2.0/. */

class email {
  // email PHP class
  // class/object for creating a new mail and send it
  //
  // function __construct()
  //   CONSTRUCTOR
  //
  // private $debug_toSingleAddress
  //   address to send mail to in debug mode
  //
  // private $subject
  //   the mail's subject line
  //
  // private $sender
  //   the mail's sender (array; fields see recipients)
  //
  // private $replyto
  //   Reply-to address (array; fields see recipients)
  //
  // private $recipients
  //   array of recipients (To: line)
  //   fields: name - real name
  //           mail - email address
  //
  // private $cc
  //   array of CC recipients (fields like recipients)
  //
  // private $bcc
  //   array of BCC recipients (fields like recipients)
  //
  // private $headers
  //   array containing all additional headers
  //   fields: name - headers name
  //           content - header content
  //
  // private $content_type
  //   the mail's content type (MIME-type) [default: text/plain]
  //
  // private $charset
  //   the mail's charset [default: iso-8859-15]
  //
  // private $mailtext
  //   the main mail body
  //
  // private $attachments
  //   array containing all attachments
  //   fields: name - attachment name
  //           content - attachment content
  //           type - MIME type of that attachment
  //
  // public function setDebugAddress($debug_email)
  //   debug mode: send only to this address
  //
  // public function setSubject($newsubject)
  //   set subject of mail
  //
  // public function setSender($email, [$name])
  //   set sender of mail
  //
  // public function setReplyTo($email, [$name])
  //   set reply-to address
  //
  // public function addRecipient($email, [$name])
  //   add a recipient to the mail
  //
  // public function addCC($email, [$name])
  //   add a CC recipient to the mail
  //
  // public function addBCC($email, [$name])
  //   add a BCC recipient to the mail
  //
  // public function addHeader($hname, [$hcontent])
  //   add a header to the mail
  //
  // public function addHeaderAddress($hname, $email, [$name])
  //   add an address header to the mail, possibly with both name and mail parts
  //
  // public function setCharset($newcharset)
  //   set charset for this mail
  //
  // public function addMailText($textpart)
  //   add some text to the mail
  //
  // public function addAttachment($aname, $acontent, [$atype])
  //   add an attachment to the mail, use given file name, content and MIME type (defaults to application/octet-stream)
  //
  // public function getAddresses([$addrtype])
  //   returns an array of all addresses this mail gets sent to
  //     fields: email, name, addrtype
  //       addrtype is one of to/cc/bcc
  //       the $addrtype parameter is a comma-separated list of such types, default: all of them
  //
  // public function send()
  //   really send the mail
  //
  // private function mimeencode($fieldtext, [$stringescape])
  //   helper function:
  //     encode given field text, ready to be placed into an e-mail MIME header
  //     if the boolean $stringescape is true, make sure this is sent as a single word in RFC2822 context (e.g. for names)
  //     see http://www.ietf.org/rfc/rfc2822.txt for the RFC in question

  private $debug_toSingleAddress = '';
  private $subject;
  private $sender = array();
  private $replyto = array();
  private $recipients = array();
  private $cc = array();
  private $bcc = array();
  private $headers = array();
  private $content_type = 'text/plain';
  private $charset = 'iso-8859-15';
  private $mailtext = '';
  private $attachments = array();

  function __construct() {
    // *** constructor ***
  }

  public function setDebugAddress($debug_email) { $this->debug_toSingleAddress = $debug_email; }

  public function setSubject($newsubject) { $this->subject = $newsubject; }

  public function setSender($email, $name = '') { $this->sender = array('mail' => $email, 'name' => $name); }

  public function setReplyTo($email, $name = '') { $this->replyto = array('mail' => $email, 'name' => $name); }

  public function addRecipient($email, $name = '') {
    $this->recipients[] = array('mail' => $email, 'name' => $name);
  }

  public function addCC($email, $name = '') {
    $this->cc[] = array('mail' => $email, 'name' => $name);
  }

  public function addBCC($email, $name = '') {
    $this->bcc[] = array('mail' => $email, 'name' => $name);
  }

  public function addHeader($hname, $hcontent = '') {
    $this->headers[] = array('name' => $hname, 'content' => $hcontent);
  }

  public function addHeaderAddress($hname, $email, $name = '') {
    if (strlen($name)) { $hcontent = $this->mimeencode($name, true).' <'.$email.'>'; }
    else { $hcontent = $email; }
    $this->headers[] = array('name' => $hname, 'content' => $hcontent);
  }

  public function setCharset($newcharset) { $this->charset = $newcharset; }

  public function addMailText($textpart) { $this->mailtext .= $textpart; }

  public function addAttachment($aname, $acontent, $atype = 'application/octet-stream') {
    $this->attachments[] = array('name' => $aname, 'content' => $acontent, 'type' => $atype);
  }

  public function getAddresses($addrtype = null) {
    // returns all addresses this mail gets sent to
    if (!is_array($addrtype)) {
      if (strlen($addrtype)) { $addrtype = explode(',', strtolower($addrtype)); }
      else { $addrtype = array('to','cc','bcc'); }
    }
    $mailaddresses = array();

    if (in_array('to', $addrtype)) {
      foreach ($this->recipients as $address) {
        if (strlen($address['mail'] ?? '')) {
          $mailaddresses[] = array('mail'=>$address['mail'],
                                   'name'=>strlen($address['name'])?$address['name']:'',
                                   'addrtype'=>'to');
        }
      }
    }
    if (in_array('cc', $addrtype)) {
      foreach ($this->cc as $address) {
        if (strlen($address['mail'] ?? '')) {
          $mailaddresses[] = array('mail'=>$address['mail'],
                                   'name'=>strlen($address['name'])?$address['name']:'',
                                   'addrtype'=>'cc');
        }
      }
    }
    if (in_array('bcc', $addrtype)) {
      foreach ($this->bcc as $address) {
        if (strlen($address['mail'] ?? '')) {
          $mailaddresses[] = array('mail'=>$address['mail'],
                                   'name'=>strlen($address['name'])?$address['name']:'',
                                   'addrtype'=>'bcc');
        }
      }
    }

    return $mailaddresses;
  }

  public function send() {
    global $util;
    $mtxt = '';
    $hdrs = 'MIME-Version: 1.0'."\n";
    $subj = $this->mimeencode($this->subject);
    if (strlen($this->sender['name'])) {
      $hdrs .= 'From: '.$this->mimeencode($this->sender['name'], true).' <'.$this->sender['mail'].'>'."\n";
    }
    else { $hdrs .= 'From: '.$this->sender['mail']."\n"; }
    if (count($this->replyto)) {
      if (strlen($this->replyto['name'])) {
        $hdrs .= 'Reply-to: '.$this->mimeencode($this->replyto['name'], true).' <'.$this->replyto['mail'].'>'."\n";
      }
      else { $hdrs .= 'Reply-to: '.$this->replyto['mail']."\n"; }
    }
    if (count($this->recipients)) {
      $recpt = '';
      foreach ($this->recipients as $address) {
        if (strlen($address['mail'] ?? '')) {
          if (strlen($address['name'])) { $recpt .= $this->mimeencode($address['name'], true).' <'.$address['mail'].'>,'; }
          else { $recpt .= $address['mail'].','; }
        }
      }
      $recpt = preg_replace('/,$/', '', $recpt);
    }
    if (!strlen($recpt)) {
      return null;
    }
    if (count($this->cc)) {
      $adrs = '';
      foreach ($this->cc as $address) {
        if (strlen($address['name'])) { $adrs .= $this->mimeencode($address['name'], true).' <'.$address['mail'].'>,'; }
        else { $adrs .= $address['mail'].','; }
      }
      $adrs = preg_replace('/,$/', '', $adrs);
      $hdrs .= (strlen($this->debug_toSingleAddress)?'X-Real-':'').'Cc: '.$adrs."\n";
    }
    if (count($this->bcc)) {
      $adrs = '';
      foreach ($this->bcc as $address) {
        if (strlen($address['name'])) { $adrs .= $this->mimeencode($address['name'], true).' <'.$address['mail'].'>,'; }
        else { $adrs .= $address['mail'].','; }
      }
      $adrs = preg_replace('/,$/', '', $adrs);
      $hdrs .= (strlen($this->debug_toSingleAddress)?'X-Real-':'').'Bcc: '.$adrs."\n";
    }
    if (count($this->headers)) {
      foreach ($this->headers as $header) {
        $hdrs .= $header['name'].': '.$header['content']."\n";
      }
    }
    if (count($this->attachments)) {
      // create random boundary, 20 chars, always beginning with KaiRo ;-)
      $boundary = 'KaiRo';
      for ($i = 1; $i <= 15; $i++) {
        $r = rand(0, 61);
        if ($r < 10) { $boundary .= chr($r + 48); }
        elseif ($r < 36) { $boundary .= chr($r + 55); }
        elseif ($r < 62) { $boundary .= chr($r + 61); }
      }
      $hdrs .= 'Content-Type: multipart/mixed; boundary="'.$boundary.'";'."\n";
      $hdrs .= 'Content-Transfer-Encoding: 7bit'."\n";
      $mtxt .= 'This part of the E-mail should never be seen. If'."\n";
      $mtxt .= 'you are reading this, consider upgrading your e-mail'."\n";
      $mtxt .= 'client to a MIME-compatible client.'."\n";
      $mtxt .= "\n".'--'.$boundary."\n";
      if (preg_match('|^text/|', $this->content_type)) {
        $mtxt .= 'Content-Type: '.$this->content_type.'; charset="'.$this->charset.'"'."\n";
      }
      else {
        $mtxt .= 'Content-Type: '.$this->content_type."\n";
      }
      $mtxt .= 'Content-Transfer-Encoding: 8bit'."\n\n";
    }
    else {
      if (preg_match('|^text/|', $this->content_type)) {
        $hdrs .= 'Content-Type: '.$this->content_type.'; charset="'.$this->charset.'"'."\n";
      }
      else {
        $hdrs .= 'Content-Type: '.$this->content_type."\n";
      }
      $hdrs .= 'Content-Transfer-Encoding: 8bit'."\n";
    }
    $mtxt .= stripslashes($this->mailtext);
    if (count($this->attachments)) {
      foreach ($this->attachments as $attach) {
        $mtxt .= "\n".'--'.$boundary."\n";
        $mtxt .= 'Content-Type: '.$attach['type'].'; name="'.$attach['name'].'";'."\n";
        if (preg_match('/^(text|message)\//', $attach['type'])) {
          $mtxt .= 'Content-Transfer-Encoding: 8bit'."\n";
          $mtxt .= 'Content-Disposition: attachment'."\n\n";
          $mtxt .= $attach['content'];
          $mtxt .= "\n";
        }
        else {
          $mtxt .= 'Content-Transfer-Encoding: base64'."\n";
          $mtxt .= 'Content-Disposition: attachment'."\n\n";
          $mtxt .= rtrim(chunk_split(base64_encode($attach['content']), 76)); ;
          $mtxt .= "\n";
        }
      }
      $mtxt .= '--'.$boundary.'--'."\n";
    }

    if (strlen($this->debug_toSingleAddress)) {
      $hdrs .= 'X-Real-To: '.$recpt."\n";
      $recpt = $this->debug_toSingleAddress;
    }

    //print('Subject: '.$util->htmlify($subj).'<br>'."\n");
    //print('To: '.$util->htmlify($recpt).'<br>'."\n");
    //print(nl2br($util->htmlify($hdrs)));
    //print(nl2br($util->htmlify($mtxt)));
    return mail($recpt, $subj, $mtxt, $hdrs);
  }

  private function mimeencode($fieldtext, $stringescape = false) {
    if (function_exists('imap_8bit')) {
      $mText = imap_8bit($fieldtext);
    }
    else {
      $mText = quoted_printable_encode($fieldtext);
    }
    $is_qpformat = ($mText != $fieldtext);
    if ($stringescape && preg_match('/[^\w !#$%&\'*+\/=?^`{|}~-]/', $mText)) {
      // if needed, make this a quoted-string instead of an atom (to speak in RFC2822 language)
      $mText = '"'.strtr($mText, array('"' => '\"', '\\' => '\\\\')).'"';
    }
    if ($is_qpformat) {
      $mText = strtr($mText, array('_' => '=5F', ' ' => '_', '?' => '=3F'));
      $mText = '=?'.strtoupper($this->charset).'?Q?'.$mText.'?=';
    }
  return $mText;
  }

  private function quoted_printable_encode($sText, $bEmulate_imap_8bit=true) {
    /* by ...deed.ztinmehc-ut.zrh@umuumu@hrz.tu-chemnitz.deed...
       from https://secure.php.net/manual/en/function.imap-8bit.php#61216

        I use the following function instead of imap_8bit
        when using PHP without the IMAP module,
        which is based on code found in
        http://www.php.net/quoted_printable_decode,
        and giving (supposedly) exactly the same results as imap_8bit,
        (tested on thousands of random strings containing lots
        of spaces, tabs, crlf, lfcr, lf, cr and so on,
        no counterexample found SO FAR:)

        AND you can force a trailing space to be encoded,
        as opposed to what imap_8bit does,
        which I consider is a violation of RFC2045,
        (see http://bugs.php.net/bug.php?id=35290)
        by commenting that one central line.
    */
    // split text into lines
    $aLines=explode(chr(13).chr(10),$sText);

    for ($i=0;$i<count($aLines);$i++) {
      $sLine =& $aLines[$i];
      if (strlen($sLine)===0) continue; // do nothing, if empty

      $sRegExp = '/[^\x09\x20\x21-\x3C\x3E-\x7E]/e';

      // imap_8bit encodes x09 everywhere, not only at lineends,
      // for EBCDIC safeness encode !"#$@[\]^`{|}~,
      // for complete safeness encode every character :)
      if ($bEmulate_imap_8bit)
        $sRegExp = '/[^\x20\x21-\x3C\x3E-\x7E]/e';

      $sReplmt = 'sprintf( "=%02X", ord ( "$0" ) ) ;';
      $sLine = preg_replace( $sRegExp, $sReplmt, $sLine );

      // encode x09,x20 at lineends
      {
        $iLength = strlen($sLine);
        $iLastChar = ord($sLine[$iLength-1]);

        //              !!!!!!!!
        // imap_8_bit does not encode x20 at the very end of a text,
        // here is, where I don't agree with imap_8_bit,
        // please correct me, if I'm wrong,
        // or comment next line for RFC2045 conformance, if you like
        if (!($bEmulate_imap_8bit && ($i==count($aLines)-1)))

        if (($iLastChar==0x09)||($iLastChar==0x20)) {
          $sLine[$iLength-1]='=';
          $sLine .= ($iLastChar==0x09)?'09':'20';
        }
      }    // imap_8bit encodes x20 before chr(13), too
      // although IMHO not requested by RFC2045, why not do it safer :)
      // and why not encode any x20 around chr(10) or chr(13)
      if ($bEmulate_imap_8bit) {
        $sLine=str_replace(' =0D','=20=0D',$sLine);
        //$sLine=str_replace(' =0A','=20=0A',$sLine);
        //$sLine=str_replace('=0D ','=0D=20',$sLine);
        //$sLine=str_replace('=0A ','=0A=20',$sLine);
      }

      // finally split into softlines no longer than 76 chars,
      // for even more safeness one could encode x09,x20
      // at the very first character of the line
      // and after soft linebreaks, as well,
      // but this wouldn't be caught by such an easy RegExp
      preg_match_all( '/.{1,73}([^=]{0,2})?/', $sLine, $aMatch );
      $sLine = implode( '=' . chr(13).chr(10), $aMatch[0] ); // add soft crlf's
    }

    // join lines into text
    return implode(chr(13).chr(10),$aLines);
  }
}
?>