<?php
/** DomFramework
    @package domframework
    @author Dominique Fournier <dominique@fournier38.fr> */

/** The class to create a complete email. Can read an email from a content */
class mail
{

  /** The complete of the mail
    */
  private $completeEmailEML = "";

  /** Private the separator between the headers and the mail. Should be
    * \r\n on a line, but special crafted mails may use something else
    */
  private $headerBodySeparator = "\r\n";

  /** Sections definitions
    * Will store the mails sections with the parameters :
    * _parent string|null The parent identifier
    * _boundary string|null The Boundary identifier
    * _contentType string The simplified Content Type
    * Content-Type string The complete Content-Type used in previous headers
    * _partsIDchild array the parts ID linked to this section
    */
  private $sections = array ();

  /** Counter for the recursion */
  private $recurse;

  /** Display the existing sections lighter than print_r, without the Carriage
    * returns
    */
  private function printSections ()
  {
    foreach ($this->sections as $sectionID=>$vals)
    {
      echo "[$sectionID] => Array (\n";
      foreach ($vals as $key=>$val)
      {
        if (is_array ($val))
        {
          echo "    [$key] => Array (\n";
          foreach ($val as $k2=>$v2)
          {
            if (is_array ($v2))
            {
              echo "        [$k2] => Array (\n";
              foreach ($v2 as $k3=>$v3)
                echo "            [$k3] => ".rtrim ($v3, "\r\n")."\n";
              echo "        )\n";
            }
            else
            {
              echo "        [$k2] => ".rtrim ($v2, "\r\n")."\n";
            }
          }
          echo "    )\n";
        }
        else
        {
          echo "    [$key] => ".rtrim ($val, "\r\n")."\n";
        }
      }
      echo ")\n\n";
    }
  }

  /** Add a new section
    * @param array $param The parameters to store
    * @return the sectionID
    */
  private function sectionAdd ($param)
  {
    $sectionID = md5 (microtime(true).rand());
    $this->sections[$sectionID] = $param;
    return $sectionID;
  }

  /** Add a new section with the default parameters
    * @return array The sectionID stored with the default parameters
    */
  private function sectionAddDefault ()
  {
    return $this->sectionAdd (
           array ("_headerBodySeparator"=>$this->headerBodySeparator,
                  "_headerCR"=>"\r\n",
                  "_headersEML"=>"",
                  "_headersArray"=>array (),
                  "_contentEML"=>"",
                  "_contentUTF"=>""));
  }

  /** Del an existing section
    * If there is one child, and the section was multiple, remove it and
    * associate the child to a new section
    * @param string $sectionID The section to delete
    */
  private function sectionDel ($sectionID)
  {
    // TODO !
  }

  /** Add a newChild to an existing section at the end of the list
    * @param string $sectionIDParent The parent modified by adding a child
    * @param string $sectionIDchild The sectionID of the child to add
    */
  private function sectionAddChild ($sectionIDParent, $sectionIDchild)
  {
    if (! array_key_exists ($sectionIDParent, $this->sections))
      throw new \Exception (_("Section parent not found"), 404);
    $this->sections[$sectionIDParent]["_partsIDchild"][] = $sectionIDchild;
    $this->sections[$sectionIDchild]["_parentID"] = $sectionIDParent;
  }

  /** Add a newChild to an existing section at the beginning of the list
    * @param string $sectionIDParent The parent modified by adding a child
    * @param string $sectionIDchild The sectionID of the child to add
    */
  private function sectionAddChildFirst ($sectionIDParent, $sectionIDchild)
  {
    if (! array_key_exists ($sectionIDParent, $this->sections))
      throw new \Exception (_("Section parent not found"), 404);
    array_unshift ($this->sections[$sectionIDParent]["_partsIDchild"],
                   $sectionIDchild);
    $this->sections[$sectionIDchild]["_parentID"] = $sectionIDParent;
  }

  /** Remove all the defined Childs in the section. Do not remove really the
    * childs !
    * @param string $sectionID the section to clean
    */
  private function sectionDelChilds ($sectionID)
  {
    if (! array_key_exists ($sectionID, $this->sections))
      throw new \Exception (_("Section not found"), 404);
    unset ($this->sections[$sectionID]["_partsIDchild"]);
  }

  /** Update the content of an existing section
    * @param string $sectionID The section to modify
    * @param array $param The parameters to update
    */
  private function sectionUpdate ($sectionID, $param)
  {
    if (! array_key_exists ($sectionID, $this->sections))
      throw new \Exception (_("Section not found"), 404);
    if (! is_array ($param))
      throw new \Exception (_("Param provided to sectionUpdate is not array"),
                            406);
    foreach ($param as $key=>$val)
    {
      $this->sections[$sectionID][$key] = $val;
    }
  }

  /** Get the list of sections ID
    * @return array the defined sectionsID
    */
  private function sectionList ()
  {
    return array_keys ($this->sections);
  }

  /** Get the section ID List with parents ID
    * @return array the defined sectionsID with the parent ID as value
    */
  private function sectionListParent ()
  {
    $res = array ();
    foreach ($this->sections as $sectionID=>$content)
    {
      if (! array_key_exists ("_parentID", $content))
        $res[$sectionID] = "";
      else
        $res[$sectionID] = $content["_parentID"];
    }
    return $res;
  }

  /** Return the content array of the section
    * @param string $sectionID The section ID to get
    * @return array The content of the section
    */
  private function sectionGet ($sectionID)
  {
    if (! array_key_exists ($sectionID, $this->sections))
      throw new \Exception (_("Section not found"), 404);
    return $this->sections[$sectionID];
  }

  /** Get the section ID of the main part
    * @return bool|string the section ID of the main part or FALSE if not found
    */
  public function sectionMainID ()
  {
    foreach ($this->sectionListParent () as $sectionID=>$parentID)
    {
      if ($parentID === "")
        return $sectionID;
    }
    return false;
  }

  /** Refresh the _headersEML from the _headersArray
    * @param string $sectionID the section to refresh
    */
  private function sectionRefreshHeadersEML ($sectionID)
  {
    $section = $this->sectionGet ($sectionID);
    $headersEML = "";
    foreach ($section["_headersArray"] as $val)
    {
      $head = key ($val);
      $value = $val[$head];
      $headersEML .= "$head: $value";
    }
    $this->sections[$sectionID]["_headersEML"] = $headersEML;
  }

  /** Read the complete mail to analyze
    * Destroy all the previous definitions of mail
    * @param string $content The complete mail to read
    */
  public function readMail ($content)
  {
    $this->sections = array ();
    $this->completeEmailEML = $content;
    $partinfo = $this->parseMessagePart ($content);
    if ($partinfo !== null)
      $this->readMailContentRecurse ($partinfo);
  }

  /** Read the content of the mail and allow the content to be also multipart.
    * Then the method is recursively called to generate the sections
    * @param array $partinfo The partinfo from parseMessagePart to analyze
    * @param string|null $sectionIDParent The parent sectionID to link with
    */
  private function readMailContentRecurse ($partinfo, $sectionIDParent=false)
  {
    if (substr ($partinfo["_contentType"], 0, 10) === "multipart/")
    {
      // multipart/alternative, multipart/related, multipart/mixed
      // Remove the content, as it is not valuable (will be stored in childs)
      $tmp = $partinfo;
      unset ($tmp["_contentEML"]);
      unset ($tmp["_contentUTF"]);
      if ($sectionIDParent === false)
        $sectionIDParent = $this->sectionAdd ($tmp);
      $boundaryArray = preg_split ("#([\r\n]+)#", $partinfo["_contentEML"],
                                   null, PREG_SPLIT_DELIM_CAPTURE);
      // Remove the first 2 dashes : the boundary is stored like in the headers
      $boundary = "";
      while (count ($boundaryArray) > 0 && substr ($boundary, 0, 2) !== "--")
      {
        // Skip the lines until the coundary is found. The boundary start by --
        $boundary = array_shift ($boundaryArray);
        $boundaryCR = array_shift ($boundaryArray);
      }
      if ($boundary === false)
        throw new \Exception (_("Can't find boundary in multipart/"), 406);
      $boundary = substr ($boundary, 2);
      unset ($boundaryArray);
      $this->sectionUpdate ($sectionIDParent,
                            array ("_boundary"=>$boundary,
                                   "_boundaryCR"=>$boundaryCR));
      $parts = preg_split ("#(--".preg_quote ($boundary)."(--)?)([\r\n]+)#",
                           $partinfo["_contentEML"],
                           null, PREG_SPLIT_DELIM_CAPTURE);
      for ($i = 0 ; $i < count ($parts) ; $i = $i + 4)
      {
        if ($parts[$i] === "")
          continue;
        $messagePart = $this->parseMessagePart ($parts[$i]);
        if ($messagePart === null ||
            ! array_key_exists ("_contentType", $messagePart))
          continue;
        $messagePart["_parentID"] = $sectionIDParent;
        $sectionIDChild = $this->sectionAdd ($messagePart);
        $this->sectionAddChild ($sectionIDParent, $sectionIDChild);
        if (substr ($messagePart["_contentType"], 0, 10) === "multipart/")
        {
          // Recursive part : multipart in multipart
          unset ($this->sections[$sectionIDChild]["_contentEML"]);
          unset ($this->sections[$sectionIDChild]["_contentUTF"]);
          $this->readMailContentRecurse ($messagePart, $sectionIDChild);
        }
      }
    }
    else
    {
      $sectionIDParent = $this->sectionAdd ($partinfo);
    }
  }

  /** Return the data for a part of the mail
    * @param string $content The content of the mail to parse
    * @return array The data content in the mail
    */
  private function parseMessagePart ($content)
  {
    // Get the HeaderBodySeparator
    $pos = strpos ($content, "\r\n\r\n");
    $headerBodySeparator = "\r\n";
    if ($pos === false)
    {
      $pos = strpos ($content, "\n\n");
      $headerBodySeparator = "\n";
    }
    if ($pos === false)
    {
      $pos = strpos ($content, "\r\r");
      $headerBodySeparator = "\r";
    }
    if ($pos === false)
      //throw new \Exception ("Can't find the header/body separator", 500);
      return array ("_contentEML"=>$content);
    // Get the headers
    $headersEML = ltrim (substr ($content, 0, $pos+
                                              strlen ($headerBodySeparator)));
    $headersArray = array ();
    if ($headersEML !== "" && $headersEML !== "--")
    {
      $prev = "";
      $prevCR = "";
      $headersSplit = preg_split ("#([\r\n]+)#", $headersEML, null,
                                  PREG_SPLIT_DELIM_CAPTURE);
      for ($i = 0 ; $i < count ($headersSplit); $i = $i + 2)
      {
        $h = $headersSplit[$i];
        if (! isset ($headersSplit[$i+1]))
          $headersSplit[$i+1] = $headerBodySeparator;
        if ($h === "" || $h === "--")
          continue;
        if ($h{0} === " " || $h{0} === "\t")
        {
          $prev .= $prevCR.$h;
          $prevCR = $headersSplit[$i+1];
        }
        elseif ($prev !== "")
        {
          $exp = explode (": ", $prev, 2);
          if (! array_key_exists (1, $exp))
          {
            //trigger_error ("Malformed mail provided: no section header",
            //               E_USER_NOTICE);
            $prev = "";
            continue;
          }
          list ($head, $value) = $exp;
          $value .= $prevCR;
          $headersArray[][$head] = $value;
          $prev = $h;
          $prevCR = $headersSplit[$i+1];
        }
        else
        {
          $prev = $h;
          $prevCR = $headersSplit[$i+1];
        }
      }
      if ($prev !== "")
      {
        $exp = explode (": ", $prev, 2);
        if (array_key_exists (1, $exp))
        {
          list ($head, $value) = $exp;
          $value .= $prevCR;
          $headersArray[][$head] = $value;
        }
      }
    }
    $contentType = $this->getHeaderValue ("Content-Type", $headersArray);
    if ($contentType === false)
    {
      // If the mail doesn't provide a Content-Type header, it is then a raw
      // text mail. Force the Content-Type to continue;
      $contentType = "text/plain; charset=utf-8; format=flowed";
    }
    $contentTypeArray = $this->contentTypeAnalyze ($contentType);
    if (! isset ($contentTypeArray["Content-Type"]))
    {
      //throw new \Exception ("Can't parse the Content-Type", 500);
      return;
    }
    $contentTransferEncoding =
                           $this->getHeaderValue ("Content-Transfer-Encoding",
                           $headersArray);
    $charset = (isset ($contentTypeArray["charset"])) ?
               $contentTypeArray["charset"] : false;
    // Get the body
    $pos = strpos ($content, $headerBodySeparator.$headerBodySeparator);
    $contentEML = substr ($content, $pos + strlen ($headerBodySeparator) * 2);
    if ($contentTransferEncoding === "quoted-printable")
      $contentUTF = $this->encodingDecode ($contentEML,
                                           $contentTransferEncoding);
    elseif ($contentTransferEncoding === "base64")
      $contentUTF = $this->encodingDecode ($contentEML,
                                           $contentTransferEncoding);
    else
      $contentUTF = $contentEML;
    if ($charset !== false)
      $contentUTF = iconv ($charset, "utf-8", $contentUTF);
    $res = array ("_headerBodySeparator"=>$headerBodySeparator,
                  "_headerCR"=>$prevCR,
                  "_headersEML"=>$headersEML,
                  "_headersArray"=>$headersArray,
                  "Content-Type"=>$contentType,
                  "_contentType"=>$contentTypeArray["Content-Type"],
                  "Content-Transfer-Encoding"=>$contentTransferEncoding,
                  "_contentEML"=>$contentEML,
                  "_contentUTF"=>$contentUTF);
    preg_match ("#; name=['\"](.+)['\"]#", $contentType, $matches);
    if (array_key_exists (1, $matches))
      $res["_name"] = $matches[1];
    if ($charset !== false)
      $res["_charset"] = $charset;
    $contentID = $this->getHeaderValue ("Content-ID", $headersArray);
    if ($contentID !== false)
      $res["Content-ID"] = $contentID;
    return $res;
  }

  /** The constuctor verify if the external libraries are available
    */
  public function __construct ()
  {
    if (! function_exists ("finfo_buffer"))
      throw new \Exception (_("Missing FileInfo PHP Extension"), 500);
    if (! function_exists ("openssl_random_pseudo_bytes"))
      throw new \Exception (_("Missing OpenSSL PHP Extension"), 500);
    // Define default headers
    $this->addHeader ("Date", date ("r"));
    $this->addHeader ("Message-ID", $this->provideMessageID ());
    $user = posix_getpwuid (posix_geteuid());
    $this->addHeader ("From", $user["name"]."@".php_uname('n'));
    $this->addHeader ("MIME-Version", "1.0");
  }

  /** Define a HTML body. If the HTML body already exists, overwrite it
    * If there is an text body, manage the boundary in alternative mode
    * @param string $htmlContent in UTF-8
    * @param string $charset to be stored in the mail
    * @param string $encoding the encoding in the mail
    */
  public function setBodyHTML ($htmlContent, $charset="utf-8",
                                             $encoding="quoted-printable")
  {
    // Look if there is an existing section with text (main or
    // multipart/alternative)
    $sectionList = $this->sectionList ();
    $sectionIDtoChange = "";
    foreach ($sectionList as $sectionID)
    {
      $section = $this->sectionGet ($sectionID);
      if (array_key_exists ("_contentType", $section) &&
          $section["_contentType"] === "text/html")
      {
        $sectionIDtoChange = $sectionID;
        break;
      }
    }
    if ($sectionIDtoChange === "")
    {
      // No existing HTML section found : need to create one
      // Check if the main section is empty to use it
      $sectionMainID = $this->sectionMainID ();
      if (!array_key_exists ("_contentType",
                             $this->sectionGet ($sectionMainID)))
      {
        $sectionIDtoChange = $sectionMainID;
      }
    }
    if ($sectionIDtoChange === "")
    {
      // No existing HTML section found : need to create one
      // Check if there is a multipart/related section without HTML to use
      $sectionList = $this->sectionList ();
      foreach ($sectionList as $sectionID)
      {
        $section = $this->sectionGet ($sectionID);
        if (! array_key_exists ("_contentType", $section)  ||
            array_key_exists ("_contentType", $section) &&
            $section["_contentType"] !== "multipart/related")
          continue;
        // Found ! $sectionID is a multipart/related section without HTML
        $sectionIDtoChange = $this->sectionAddDefault ();
        $this->sectionAddChildFirst ($sectionID, $sectionIDtoChange);
      }
    }
    if ($sectionIDtoChange === "")
    {
      // No existing HTML section found : need to create one
      // Check if there is an text part alone (to be pushed in
      // multipart/alternative)
      foreach ($sectionList as $sectionID)
      {
        $section = $this->sectionGet ($sectionID);
        if (! array_key_exists ("_contentType", $section) ||
              $section["_contentType"] !== "text/plain")
          continue;
        // Found ! $sectionID is text/plain section
        // Create a multipart/alternative section
        // Move the text section in the multipart/alternative section
        $boundary = $this->getBoundary ();
        $multiID = $this->sectionAddDefault();
        $this->moveChilds ($multiID);
        $this->addHeader ("Content-Type", "multipart/alternative;\r\n".
                                          "  boundary=$boundary\r\n",
                          $multiID);
        $this->sectionUpdate ($multiID,
          array ("_contentType"=>"multipart/alternative",
                 "_boundary"=>$boundary,
                 "_boundaryCR"=>"\r\n",
                ));

        // Add a HTML section in the multipart/alternative section after the
        // defined text section.
        $sectionIDtoChange = $this->sectionAddDefault ();
        $this->sectionAddChild ($multiID, $sectionIDtoChange);
      }
    }
    if ($sectionIDtoChange === "")
    {
      // No existing section found : need to create one
      throw new \Exception (_("Can't find the place to store the HTML"), 500);
    }
    $htmlContent = iconv ("utf-8", $charset, $htmlContent);
    $part["_charset"] = $charset;
    $part["_contentType"] = "text/html";
    $this->setHeader ("Content-Transfer-Encoding", $encoding,
                      $sectionIDtoChange);
    // TODO : Add $part["_contentUTF"] ?
    $part["_contentEML"] = $this->encodingEncode ($htmlContent, $encoding)."\n";
    $this->setHeader ("Content-Type", "text/html; charset=$charset",
                      $sectionIDtoChange);
    if (isset ($boundary)) $part["_boundary"] = $boundary;
    if (isset ($boundaryCR)) $part["_boundaryCR"] = $boundaryCR;
    $this->sectionUpdate ($sectionIDtoChange, $part);
    $this->createMailEML ();
  }

  /** Add a Text body. If the text body already exists, overwrite it
    * If there is an HTML body, manage the boundary in alternative mode
    * @param string $textContent in UTF-8
    * @param string $charset to be stored in the mail
    * @param string $encoding the encoding in the mail
    */
  public function setBodyText ($textContent, $charset="utf-8",
                                             $encoding="quoted-printable")
  {
    // Look if there is an existing section with text (main or
    // multipart/alternative)
    $sectionList = $this->sectionList ();
    $sectionIDtoChange = "";
    foreach ($sectionList as $sectionID)
    {
      $section = $this->sectionGet ($sectionID);
      if (array_key_exists ("_contentType", $section) &&
          $section["_contentType"] === "text/plain")
      {
        $sectionIDtoChange = $sectionID;
        break;
      }
    }
    if ($sectionIDtoChange === "")
    {
      // No existing section found : need to create one
      // Check if the main section is empty to use it
      $sectionMainID = $this->sectionMainID ();
      if (!array_key_exists ("_contentType",
                             $this->sectionGet ($sectionMainID)))
      {
        $sectionIDtoChange = $sectionMainID;
      }
    }
    if ($sectionIDtoChange === "")
    {
      // No existing section found : need to create one
      // Check if there is an html part alone (to be pushed in
      // multipart/alternative)
      foreach ($sectionList as $sectionID)
      {
        $section = $this->sectionGet ($sectionID);
        if (! array_key_exists ("_contentType", $section) ||
              $section["_contentType"] !== "text/html")
          continue;
        $sectionIDhtml = $sectionID;
        // Found ! $sectionID is text/html section
        // Create a multipart/alternative section
        // Move the text section in the multipart/alternative section
        $boundary = $this->getBoundary ();
        $multiID = $this->sectionAddDefault();
        $this->moveChilds ($multiID);
        $this->addHeader ("Content-Type", "multipart/alternative;\r\n".
                                            "  boundary=$boundary\r\n",
                          $multiID);
        $this->sectionUpdate ($multiID,
          array ("_contentType"=>"multipart/alternative",
                 "_boundary"=>$boundary,
                 "_boundaryCR"=>"\r\n",
                ));
        // Add a HTML section in the multipart/alternative section
        $sectionIDtoChange = $this->sectionAddDefault ();
        $this->sectionAddChildFirst ($multiID, $sectionIDtoChange);
      }
    }
    if ($sectionIDtoChange === "")
    {
      // No existing section found : need to create one
      throw new \Exception (_("Can't find the place to store the TEXT"), 500);
    }
    $textContent = iconv ("utf-8", $charset, $textContent);
    $part["_charset"] = $charset;
    $part["_contentType"] = "text/plain";
    $this->setHeader ("Content-Transfer-Encoding", $encoding,
                      $sectionIDtoChange);
    $part["_contentEML"] = $this->encodingEncode ($textContent, $encoding)."\n";
    $part["_contentUTF"] = $textContent;
    $this->setHeader ("Content-Type", "text/plain; charset=$charset",
                      $sectionIDtoChange);
    if (isset ($boundary)) $part["_boundary"] = $boundary;
    if (isset ($boundaryCR)) $part["_boundaryCR"] = $boundaryCR;
    $this->sectionUpdate ($sectionIDtoChange, $part);
    $this->createMailEML ();
  }

  /** Return the HTML body if exists in UTF-8. If the body is not in UTF-8, it
    * is converted
    * Return false if it doesn't exists
    * @return string|false The HTML body converted in UTF-8 or false if there is
    *         no HTML part in the mail
    */
  public function getBodyHTML ()
  {
    $sectionList = $this->sectionList ();
    $sectionIDtoChange = "";
    foreach ($sectionList as $sectionID)
    {
      $section = $this->sectionGet ($sectionID);
      if (array_key_exists ("_contentType", $section) &&
          $section["_contentType"] === "text/html")
      {
        $encoding = $this->getHeaderValue ("Content-Transfer-Encoding",
                                      $section["_headersArray"]);
        $body = $this->encodingDecode ($section["_contentEML"],
                                       $encoding);
        return iconv ($section["_charset"], "UTF-8", $body);
      }
    }
    return false;
  }

  /** Get the text body if exists in UTF-8. If the body is not in UTF-8, it is
    * converted
    * Return false if it doesn't exists
    * @return string|false The Text body converted in UTF-8 or false if there is
    *         no Text part in the mail
    */
  public function getBodyText ()
  {
    $sectionList = $this->sectionList ();
    $sectionIDtoChange = "";
    foreach ($sectionList as $sectionID)
    {
      $section = $this->sectionGet ($sectionID);
      if (array_key_exists ("_contentType", $section) &&
          $section["_contentType"] === "text/plain")
      {
        $encoding = $this->getHeaderValue ("Content-Transfer-Encoding",
                                      $section["_headersArray"]);
        $body = $this->encodingDecode ($section["_contentEML"],
                                       $encoding);
        return iconv ($section["_charset"], "UTF-8", $body);
      }
    }
    return false;
  }

  /** Move the sections where the parent is defined to $oldParentID to the
    * $newParentID.
    * Move the headers from the valid sections to the newParent, except the
    * Content-XX lines
    * @param string $newParentID The Parent which will be modified
    * @param string|null $oldParentID The oldParent to look for
    */
  private function moveChilds ($newParentID, $oldParentID=false)
  {
    if ($newParentID === $oldParentID)
      throw new \Exception ("moveChilds : old and new ParentID are the same",
        406);
    foreach ($this->sections as $sectionID=>$section)
    {
      if ($newParentID === $sectionID)
        continue;
      if ((! isset ($section["_parentID"]) && $oldParentID === false) ||
          $oldParentID === $section["_parentID"])
      {
        $this->sections[$sectionID]["_parentID"] = $newParentID;
        $this->sections[$newParentID]["_partsIDchild"][] = $sectionID;
        $multipartHeaders = array ();
        $headersEML = "";
        foreach ($section["_headersArray"] as $key=>$val)
        {
          $head = key ($val);
          $value = $val[$head];
          if (substr ($head, 0, 8) !== "Content-")
          {
            $this->addHeader ($head, $value, $newParentID);
            try
            {
              // Removing the Received: headers entries can only be done one
              // time. An exception is raised, but it is not important
              $this->delHeader ($head, $sectionID);
            }
            catch (Exception $e)
            {
            }
          }
        }
      }
      else
      {
        // Section not attached to the wanted parent : skip it
      }
    }

    // Remove empty sections
    foreach ($this->sections as $sectionID=>$section)
    {
      if (count ($section["_headersArray"]) === 0 &&
          rtrim ($section["_headersEML"]) === "" &&
          rtrim ($section["_contentEML"]) === "")
      {
        if (array_key_exists ("_parentID", $section))
        {
          foreach ($this->sections[$section["_parentID"]]["_partsIDchild"] as
           $key=>$val)
          if ($val === $sectionID)
            unset ($this->sections[$section["_parentID"]]["_partsIDchild"][$key]
                  );
        }
        unset ($this->sections[$sectionID]);
      }
    }
  }

  /** Add an attachment to the mail.
    * The allowed encodings are "quoted-printable" or "base64"
    * @param string $name The name of the file
    * @param string $fileContent The content of the file in binary
    * @param string|null $encoding The output encoding. Can be
    *        base64/quoted-printable
    * @param boolean|null $inline Store the file in inline mode
    *        (multipart/related)
    *        If false, store the file in attached mode (multipart/mixed)
    */
  public function addAttachment ($name, $fileContent, $encoding="base64",
                                 $inline=false)
  {
    if ($this->getBodyHTML() === false && $inline !== false)
      $this->setBodyHTML ("No HTML provided by inline file added");
    // Look if there is a multipart/mixed where adding the new section. If not,
    // create it
    $multipart = ($inline === false) ? "multipart/mixed" : "multipart/related";
    $sectionList = $this->sectionList ();
    $sectionIDMixed = "";
    foreach ($sectionList as $sectionID)
    {
      $section = $this->sectionGet ($sectionID);
      if (!array_key_exists ("_contentType", $section) ||
          array_key_exists ("_contentType", $section) &&
          $section["_contentType"] !== $multipart)
        continue;
      // Found a multipart/mixed. Will add the new attachment section to it
      $sectionIDMixed = $sectionID;
    }
    if ($sectionIDMixed === "")
    {
      // No multipart/mixed. Need to create one
      $headersEML = "";
      $sectionIDMixed = $this->sectionAddDefault ();
      // Move all the existing sections in the new multipart/mixed
      $this->moveChilds ($sectionIDMixed);
      $boundary = $this->getBoundary ();
      $this->addHeader ("Content-Type", "$multipart;\r\n".
                                        "  boundary=$boundary\r\n",
                       $sectionIDMixed);
      $this->sectionUpdate ($sectionIDMixed,
        array ("_contentType"=>$multipart,
               "_boundary"=>$boundary,
               "_boundaryCR"=>"\r\n",
              ));
    }
    if ($sectionIDMixed === "")
    {
      throw new \Exception (
       "Can't find the multipart/mixed section to add an attachment");
    }
    // Add the new section to the mixed section
    $sectionID = $this->sectionAddDefault ();
    $this->sectionAddChild ($sectionIDMixed, $sectionID);
    $finfo = new \finfo(FILEINFO_MIME);
    $mimetype = $finfo->buffer($fileContent);
    $this->addHeader ("Content-Type", "$mimetype; name=\"".
                      str_replace ("\"", "=22",
                        $this->encodeHeaderStringWithPosition ($name,
                          "quoted-printable",
                          strlen ("Content-Type: $mimetype; name=")))."\"\r\n",
                      $sectionID);
    if ($inline === false)
      $this->addHeader ("Content-Disposition", "attachment; filename=\"".
                        str_replace ("\"", "=22",
                          $this->encodeHeaderStringWithPosition ($name,
                            "quoted-printable",
                            strlen ("Content-Disposition: attachment; ".
                                    "filename="))).
                        "\"\r\n",
                        $sectionID);
    else
    {
      $this->addHeader ("Content-Disposition", "inline; filename=".
                        str_replace ("\"", "=22",
                          $this->encodeHeaderStringWithPosition ($name,
                            "quoted-printable",
                             strlen ("Content-Disposition: inline; filename=")
                          ))."\r\n",
                        $sectionID);
      $contentID = $this->provideMessageID ();
      $this->addHeader ("Content-ID", "$contentID\r\n", $sectionID);
    }
    $this->addHeader ("Content-Transfer-Encoding", "$encoding\r\n", $sectionID);
    $part["_name"] = $name;
    $part["_contentEML"] = $this->encodingEncode ($fileContent, $encoding);
    $part["_mimetype"] = $mimetype;
    $part["_sizeReal"] = strlen ($fileContent);
    $this->sectionUpdate ($sectionID, $part);
    $this->createMailEML ();
    if ($inline === true)
      return substr ($contentID, 1, -1);
  }

  /** Add an inline attachment to the mail.
    * The allowed encodings are "quoted-printable" or "base64"
    * Return the Content-ID needed to be used in HTML page like :
    * <img src='cid:XXXXXXXXXX'/>
    * @param string $name The name of the file
    * @param string $fileContent The content of the file in binary
    * @param string|null $encoding The output encoding. Can be
    *        base64/quoted-printable
    * @return string The content ID created
    */
  public function addAttachmentInline ($name, $fileContent,  $encoding="base64")
  {
    return $this->addAttachment ($name, $fileContent, $encoding, true);
  }

  /** Get an attachment of the mail
    * @param integer $number the number of attach to get starting to 0
    * @param boolean|null $inline Return only the attachments Inline if true
    * @return the content of the attachment. Can be binary
    */
  public function getAttachment ($number, $inline = false)
  {
    $attachmentIDs = $this->getAttachmentID ($inline);
    if (! array_key_exists ($number, $attachmentIDs))
      throw new \Exception (sprintf (_("Attachment '%d' not found"), $number),
                            404);
    $part = $this->sectionGet ($attachmentIDs[$number]);
    $encoding = $this->getHeaderValue ("Content-Transfer-Encoding",
                                       $part["_headersArray"]);
    return $this->encodingDecode ($part["_contentEML"], $encoding);
  }

  /** Get the attachment details
    * @param integer $number the number of attach to get starting to 0
    * @param boolean|null $inline Return only the attachments Inline if true
    * @return array containing the information of the attachment
    */
  public function getAttachmentDetails ($number, $inline = false)
  {
    $attachmentIDs = $this->getAttachmentID ($inline);
    if (! array_key_exists ($number, $attachmentIDs))
      throw new \Exception (sprintf (_("Attachment '%d' not found"), $number),
                            404);
    $part = $this->sectionGet ($attachmentIDs[$number]);
    foreach ($part as $key=>$val)
    {
      if ($key{0} === "_")
      {
        if ($key !== "_contentEML" && $key !== "_contentUTF" &&
            $key !== "_parentID" && $key !== "_headersArray" &&
            $key !== "_headersEML" && $key !== "_headerCR" &&
            $key !== "_headerBodySeparator")
          $res[substr ($key, 1)] = $val;
      }
      else
        $res[$key] = $val;
    }
    return $res;
  }

  /** Return the list of the sectionID containing a attachment. Contains the
    * inline attachments too.
    * @param boolean $inline Return only the sections Inline if true
    * @return array The sectionIDs
    */
  private function getAttachmentID ($inline = false)
  {
    $res = array ();
    foreach ($this->sections as $sectionID=>$section)
    {
      $disposition = $this->getHeaderValue ("Content-Disposition",
                                            $section["_headersArray"]);
      if ($disposition === false)
        continue;
      if ($inline === true && substr ($disposition, 0, 6) === "inline")
        $res[] = $sectionID;
      elseif ($inline === false &&
              substr ($disposition, 0, 10) === "attachment")
        $res[] = $sectionID;
    }
    return $res;
  }

  /** Add a To: header. If it already exists, add a new recipient
    * @param string $toMail The mail to add
    * @param string|null $toName The name of the recipient
    */
  public function addTo ($toMail, $toName = "")
  {
    if (strspn ($toName, "abcdefghijklmnopqrstuvwxyz".
                         "ABCDEFGHIJKLMNOPQRSTUVWXYZ".
                         "0123456789 -_") !== strlen ($toName))
      $toName = $this->encodeHeaders ("To", $toName,
                                      "quoted-printable");
    if ($toName !== "")
      $toName .= " ";
    $toField = "$toName<$toMail>";
    $oldTo = $this->getTo ();
    if ($oldTo !== false)
      $this->setHeader ("To", rtrim ($oldTo).",\r\n    $toField");
    else
      $this->setHeader ("To", $toField);
  }

  /** Get the To Header as it is written in the mail
    * @return string The To Header defined in the mail
    */
  public function getTo ()
  {
    return $this->getHeader ("To");
  }

  /** Add a From: header. If it already exists, overwrite the existing one
    * @param string $fromMail The from Mail to define
    * @param string|null $fromName The from Name to define
    */
  public function setFrom ($fromMail, $fromName= "")
  {
    if (strspn ($fromName, "abcdefghijklmnopqrstuvwxyz".
                           "ABCDEFGHIJKLMNOPQRSTUVWXYZ".
                           "0123456789 -_") !== strlen ($fromName))
      $fromName = $this->encodeHeaders ("From", $fromName,
                                        "quoted-printable");
    if ($fromName !== "")
      $fromName .= " ";
    $this->setHeader ("From", "$fromName<$fromMail>");
  }

  /** Return the From header as it is written in the mail
    * @return string The From Header defined in the mail
    */
  public function getFrom ()
  {
    return $this->getHeader ("From");
  }

  /** Return the From header converted to array with mail and name keys
    * @return array The From details
    */
  public function getFromArray ()
  {
    $from = $this->getHeader ("From");
    $res = array ();
    $from = $this->decodeHeaders ("From", $from);
    $from = $this->convertPeopleToArray ($from);
    return reset ($from);
  }

  /** Set the subject
    * @param string $subject In UTF8
    */
  public function setSubject ($subject)
  {
    $this->setHeader ("Subject",
                      $this->encodeHeaders ("Subject", $subject,
                                            "quoted-printable"));
  }

  /** Set the Date
    * @param string $date In RFC 2822 format
    */
  public function setDate ($date)
  {
    // TODO : Check if the date format is valid
    $this->setHeader ("Date", $date);
  }

  /** Set the Date
    * @param string $timestamp In Timestamp format
    */
  public function setDateTimestamp ($timestamp)
  {
    // TODO : Check if the timestamp is valid
    $this->setHeader ("Date", date ("r", $timestamp));
  }

  /** Get the Date header if defined.
    * Return false if not defined
    * @return string|bool The date Header if defined or false if not defined
    */
  public function getDate ()
  {
    return $this->getHeader ("Date");
  }

  /** Return the Date header (if defined) in timestamp
    * Return false if not defined
    * @return integer|bool The date Header if defined or false if not defined
    */
  public function getDateTimestamp ()
  {
    $datetimestamp = false;
    $date = rtrim ($this->getDate ());
    if ($date !== false)
    {
      $dateTimestamp = DateTime::createFromFormat (DateTime::RFC2822,
                                                   $date);
      if ($dateTimestamp === false)
        $dateTimestamp = DateTime::createFromFormat (DateTime::RFC822,
                                                     $date);
      if ($dateTimestamp !== false)
        $dateTimestamp  = $dateTimestamp->getTimestamp();
    }
    return $dateTimestamp;
  }

  /** Set a generic header
    * @param string $header The name of the Header (without colon)
    * @param string $value The value the store. The format must be correct !
    * @param string|null $sectionID The section to modify. If null, use the main
    */
  public function setHeader ($header, $value, $sectionID=null)
  {
    if (substr ($value, -1) !== "\n" &&
        substr ($value, -1) !== "\r" &&
        substr ($value, -2) !== "\r\n")
      $value .= "\r\n";
    if ($sectionID === null)
    {
      $sectionMainID = $this->sectionMainID ();
      if ($sectionMainID === false)
        $sectionMainID = $this->sectionAddDefault ();
    }
    else
    {
      if (! array_key_exists ($sectionID, $this->sections))
        throw new \Exception ("Wanted section not found in setHeader", 404);
      $sectionMainID = $sectionID;
    }

    $found = false;
    foreach ($this->sections[$sectionMainID]["_headersArray"] as $key=>$val)
    {
      $head = key ($val);
      if ($head === $header)
      {
        $this->sections[$sectionMainID]["_headersArray"][$key][$header] =
                                                                         $value;
        $found = true;
      }
    }
    if ($found === false)
      $this->sections[$sectionMainID]["_headersArray"][][$header] = $value;
    // Re-create the _headersEML for the section
    $_headerEML = "";
    foreach ($this->sections[$sectionMainID]["_headersArray"] as $val)
    {
      $head = key ($val);
      $value = $val[$head];
      $_headerEML .= "$head: $value";
    }
    $this->sections[$sectionMainID]["_headersEML"] = $_headerEML;
    $this->createMailEML ();
  }

  /** Add a generic header
    * @param string $header The name of the Header (without colon)
    * @param string $value The value the store. The format must be correct !
    * @param string|null $sectionID The section to modify. If null, use the main
    */
  public function addHeader ($header, $value, $sectionID=null)
  {
    if (substr ($value, -1) !== "\n" &&
        substr ($value, -1) !== "\r" &&
        substr ($value, -2) !== "\r\n")
      $value .= "\n";
    if ($sectionID === null)
    {
      $sectionMainID = $this->sectionMainID ();
      if ($sectionMainID === false)
        $sectionMainID = $this->sectionAddDefault ();
    }
    else
    {
      if (! array_key_exists ($sectionID, $this->sections))
        throw new \Exception ("Wanted section not found in addHeader", 404);
      $sectionMainID = $sectionID;
    }
    if ($header === "Return-Path")
    {
      // Must be placed on the first line and must be unique
      reset ($this->sections[$sectionMainID]["_headersArray"]);
      if (key_exists (0, $this->sections[$sectionMainID]["_headersArray"]) &&
          key_exists ("Return-Path", $this->sections[$sectionMainID]["_headersArray"][0]))
      {
        // Remove the old one
        array_shift ($this->sections[$sectionMainID]["_headersArray"]);
        $this->sections[$sectionMainID]["_headersEML"] =
          substr ($this->sections[$sectionMainID]["_headersEML"],
            strpos ($this->sections[$sectionMainID]["_headersEML"], "\n") +1);
      }
      array_unshift ($this->sections[$sectionMainID]["_headersArray"],
        array ($header => $value));
      $this->sections[$sectionMainID]["_headersEML"] = "$header: $value".
        $this->sections[$sectionMainID]["_headersEML"];
    }
    else
    {
      // The "normal" headers are places sequentially at the end of the headers
      $this->sections[$sectionMainID]["_headersArray"][][$header] = $value;
      // TODO : Encode ? Strip ?
      $this->sections[$sectionMainID]["_headersEML"] .= "$header: $value";
    }
    $this->createMailEML ();
  }

  /** Delete a specific header
    * @param string $header The header to remove
    * @param string|null $sectionID The section to modify. If null, use the main
    */
  public function delHeader ($header, $sectionID=null)
  {
    if ($sectionID === null)
    {
      $sectionMainID = $this->sectionMainID ();
      if ($sectionMainID === false)
        $sectionMainID = $this->sectionAddDefault ();
    }
    else
    {
      if (! array_key_exists ($sectionID, $this->sections))
        throw new \Exception ("Wanted section not found in delHeader", 404);
      $sectionMainID = $sectionID;
    }
    $found = false;
    foreach ($this->sections[$sectionMainID]["_headersArray"] as $key=>$val)
    {
      $head = key ($val);
      if ($head === $header)
      {
        unset ($this->sections[$sectionMainID]["_headersArray"][$key]);
        $found = true;
      }
    }
    if ($found === false)
      throw new \Exception (sprintf ("Header to remove '%s' not found",
                                     $header), 404);
    // Re-create the _headersEML for the section
    $_headerEML = "";
    foreach ($this->sections[$sectionMainID]["_headersArray"] as $val)
    {
      $head = key ($val);
      $value = $val[$head];
      $_headerEML .= "$head: $value";
    }
    $this->sections[$sectionMainID]["_headersEML"] = $_headerEML;
    $this->createMailEML ();
  }

  /** Get a generic header
    * If there is multiple headers with the same name, return the first
    * @param string $header The header to get
    * @param array|null $headers Optional headers to examine
    * @return string|bool the literal value or false if it doesn't exist
    */
  public function getHeader ($header, $headers=null)
  {
    if ($headers === null)
    {
      $sectionMainID = $this->sectionMainID ();
      if ($sectionMainID === false)
        $headers = array ();
      else
        $headers = $this->sections[$sectionMainID]["_headersArray"];
    }
    foreach ($headers as $key=>$val)
    {
      $head = key ($val);
      $value = $val[$head];
      if ($head === $header)
        return $value;
    }
    return false;
  }

  /** Get a generic header with removing the carriage return
    * If there is multiple headers with the same name, return the first
    * @param string $header The header to get
    * @param array $headers The _headersArray array
    * @return string|bool the literal value or false if it doesn't exist
    */
  public function getHeaderValue ($header, $headers=null)
  {
    if ($headers === null)
    {
      $sectionMainID = $this->sectionMainID ();
      if ($sectionMainID === false)
        $headers = array ();
      else
        $headers = $this->sections[$sectionMainID]["_headersArray"];
    }
    foreach ($headers as $key=>$val)
    {
      $head = key ($val);
      $value = $val[$head];
      if ($head === $header)
      {
        $value = preg_replace ("#[\r\n]+[ \t]+#", " ", $value);
        if (substr ($value, -2) === "\r\n")
          return substr ($value, 0, -2);
        return substr ($value, 0, -1);
      }
    }
    return false;
  }

  /** Create the complete mail structure
    */
  public function createMailEML ()
  {
    $complete = "";
    $this->recurse = 0;
    foreach ($this->sectionListParent() as $sectionID=>$sectionParent)
    {
      if ($sectionParent !== "")
        continue;
      $part = $this->sectionGet ($sectionID);
      $complete .= $part["_headersEML"];
      $complete .= $part["_headerBodySeparator"];
      if (array_key_exists ("_contentEML", $part))
        $complete.= $part["_contentEML"];
      $complete .= $this->createMailEMLSub ($part);
    }
    $this->completeEmailEML = $complete;
  }

  /** Recursive email EML creation for childs
    * @param array $parent The parent array
    */
  private function createMailEMLSub ($parent)
  {
    $this->recurse++;
    if ($this->recurse > 120)
      throw new \Exception ("Recurse createMailEMLSub > 120", 500);
    if (!array_key_exists ("_partsIDchild", $parent))
      return "";
    $complete = "";
    foreach ($parent["_partsIDchild"] as $childID)
    {
      $child = $this->sectionGet ($childID);
      // The boundary is not defined in the child, but in the parent
      if (array_key_exists ("_boundary", $parent))
        $complete .= "--".$parent["_boundary"].$parent["_boundaryCR"];
      if (array_key_exists ("_headersEML", $child))
        $complete .= $child["_headersEML"];
      if (array_key_exists ("_headerBodySeparator", $child))
        $complete .= $child["_headerBodySeparator"];
      $complete .= $this->createMailEMLSub ($child);
      if (array_key_exists ("_contentEML", $child))
        $complete.= $child["_contentEML"];
    }
    if (array_key_exists ("_boundary", $parent))
      $complete .= "--".$parent["_boundary"]."--".$parent["_boundaryCR"];
    return $complete;
  }

  /** Return the complete mail
    * @return string The complete mail
    */
  public function getMail ()
  {
    if (trim ($this->getBodyHTML()) === "No HTML provided by inline file added")
      throw new \Exception ("No HTML provided by inline file added", 500);

    return $this->completeEmailEML;
  }

  /** Return an array with the details of the mail :
    * the number of attachments, the from, to, subject in UTF-8, if there is
    * a text and/or html body
    * @return array The details of the mail
    */
  public function getDetails ()
  {
    $bodyTextExists = false;
    $bodyHTMLExists = false;
    $attachmentNb = count ($this->getAttachmentID ());
    $attachmentInlineNb = count ($this->getAttachmentID (true));
    foreach ($this->sections as $sectionID=>$section)
    {
      if (array_key_exists ("_contentType", $section) &&
          $section["_contentType"] === "text/plain")
        $bodyTextExists = true;
      if (array_key_exists ("_contentType", $section) &&
          $section["_contentType"] === "text/html")
        $bodyHTMLExists = true;
    }
    unset ($sectionID);
    unset ($section);
    for ($i = 0 ; $i < $attachmentNb ; $i ++)
      $attachmentDetails[$i] = $this->getAttachmentDetails($i);
    for ($i = 0 ; $i < $attachmentInlineNb ; $i ++)
      $attachmentInlineDetails[$i] = $this->getAttachmentDetails($i, true);
    unset ($i);
    $size = strlen ($this->getMail());
    $from = trim ($this->getHeader ("From"));
    if ($from !== false)
    {
      $fromArray = $this->convertPeopleToArray (
                         $this->decodeHeaders ("From", $from));
    }
    $to = trim ($this->getHeader ("To"));
    if ($to !== false)
    {
      $toArray = $this->convertPeopleToArray (
                       $this->decodeHeaders ("To", $to));
    }
    $date = trim ($this->getDate ());
    $dateTimestamp = $this->getDateTimestamp ();
    $subject = $this->getHeaderValue ("Subject");
    return get_defined_vars();
  }

  /** Create a boundary
    * @return string the textual boundary
    */
  private function getBoundary ()
  {
    $data = openssl_random_pseudo_bytes (16);
    $data[6] = chr(ord($data[6]) & 0x0f | 0x40); // set version to 0010
    $data[8] = chr(ord($data[8]) & 0x3f | 0x80); // set bits 6-7 to 10
    return "-----".vsprintf ('%s%s%s%s%s%s%s%s',
                               str_split (bin2hex ($data), 4));
  }

  /** Create a messageID
    * @return string the textual MessageID
    */
  public function provideMessageID ()
  {
    $data = openssl_random_pseudo_bytes (16);
    $data[6] = chr(ord($data[6]) & 0x0f | 0x40); // set version to 0010
    $data[8] = chr(ord($data[8]) & 0x3f | 0x80); // set bits 6-7 to 10
    return "<".vsprintf ('%s%s-%s-%s-%s-%s%s%s',
                               str_split (bin2hex ($data), 4))."@".
            php_uname('n').">";
  }

  /** Convert the content to correct encoding.
    * The allowed encodings are "quoted-printable" or "base64" or "flowed"
    * Cut the long lines to 76 chars with the correct separator
    * @param string $content The content to encode
    * @param string $encoding The encoding to use
    * @return string the content encoded by $encoding
    */
  private function encodingEncode ($content, $encoding)
  {
    if ($encoding === "quoted-printable")
    {
      $tmp = quoted_printable_encode ($content);
      return $tmp;
    }
    elseif ($encoding === "base64")
    {
      $tmp = base64_encode ($content);
      return chunk_split ($tmp);
    }
    elseif ($encoding === "flowed")
    {
      return chunk_split ($content);
    }
    throw new \Exception (sprintf (
                          _("Invalid encoding provided to encodingEncode : %s"),
                          $encoding),
                          500);
  }

  /** Decode the content with correct encoding.
    * The allowed encodings are "quoted-printable" or "base64" or "8bit"
    * @param string $content The content to decode
    * @param string $encoding The encoding to use
    * @return the content decoded by $encoding
    */
  private function encodingDecode ($content, $encoding)
  {
    if ($encoding === "quoted-printable")
      return quoted_printable_decode ($content);
    elseif ($encoding === "base64")
      return base64_decode ($content);
    elseif ($encoding === "8bit" || $encoding === "7bit" || $encoding === false)
      return $content;
    throw new \Exception (sprintf (
                        _("Invalid encoding provided to encodingDecode : '%s'"),
                          $encoding),
                          500);
  }

  /** Encode a string to be compliant with MIME (used in headers)
    * @param string $header The header to be used. Will not be returned, but the
    *        length of the result will be adapted to it
    * @param string $content The content to encode
    * @param string $encoding The encoding to use.
    * The allowed encodings are "quoted-printable" or "base64"
    * @return string the content encoded by $encoding
    */
  private function encodeHeaders ($header, $content, $encoding)
  {
    $prefs = array ("input-charset" => "utf-8",
                    "output-charset" => "utf-8");
    if ($encoding === "quoted-printable")
      $prefs["scheme"] = "Q";
    elseif ($encoding === "base64")
      $prefs["scheme"] = "B";
    else
      throw new \Exception (_("Invalid encoding provided to encodeHeaders"),
                          500);
    return substr (iconv_mime_encode ($header, $content, $prefs),
                   strlen ($header)+2);
  }

  /** Convert the header to text
    * @param string $header The header to decode
    * @param string $content The content of the header to decode
    * @return string the header converted
    */
  private function decodeHeaders ($header, $content)
  {
    return substr (iconv_mime_decode ("$header: $content", 0, "utf-8"),
                   strlen ($header)+2);
  }

  /** Encode a header string not starting on first column. The number of chars
    * need to be skipped is passed as argument. The function will correctely
    * managethe associated carriage returns
    * @param string $content The content to encode
    * @param string $encoding The The encoding to use.
    * The allowed encodings are "quoted-printable" or "base64"
    * @param integer $blanks Initial blanks to be added on string
    * @return string the content encoded by $encoding
    */
  private function encodeHeaderStringWithPosition ($content, $encoding, $blanks)
  {
    $prefs = array ("input-charset" => "utf-8",
                    "output-charset" => "utf-8");
    if ($encoding === "quoted-printable")
      $prefs["scheme"] = "Q";
    elseif ($encoding === "base64")
      $prefs["scheme"] = "B";
    else
      throw new \Exception (_("Invalid encoding provided to ".
                              "encodeHeaderStringWithPosition"),
                          500);
    return substr (iconv_mime_encode (str_repeat (" ", $blanks), $content,
                                      $prefs),
                   $blanks+2);
  }

  /** Convert a From/To string to array. Manage multiple recipients
    * Ex. : toto toto <toto@toto.com>, titi <titi@titi.com>
    *      array (array ("name"=>"toto toto", "mail"=>"toto@toto.com"),
    *             array ("name"=>"titi", "mail"=>"titi@titi.com"))
    * @param string $data The From/To field content
    * @return array The array with the converted data
    */
  public function convertPeopleToArray ($data)
  {
    $elements = explode (",", $data);
    $res = array ();
    foreach ($elements as $element)
    {
      @list ($name, $mail) = explode ("<", $element);
      if ($mail === null)
      {
        $mail = $name;
        $name = "";
      }
      else
      {
        $name = trim ($name);
        $mail = substr (trim ($mail), 0, -1);
      }
      $array = array ("name"=>$name, "mail"=>$mail);
      $res[] = $array;
    }
    return $res;
  }

  /** Analyze the Content-Type line and return an array with the values
    * @param string $contentType The content Type to analyze
    * @return array The analyzed Content-Type
    */
  public function contentTypeAnalyze ($contentType)
  {
    $contentType = preg_replace ("#[\r\n]+[ \t]+#", " ", $contentType);
    $elements = explode (";", $contentType);
    $res = array ();
    foreach ($elements as $elem)
    {
      @list ($key, $val) = explode ("=", $elem, 2);
      if ($val === null)
        $res["Content-Type"] = $key;
      else
      {
        if ($val{0} === "'" || $val{0} === "\"")
          $val = substr ($val, 1, -1);
        $res[trim ($key)] = $val;
      }
    }
    return $res;
  }
}