class MY_Email extends CI_Email
{
    protected function matched_replace_between($data, $delimiter1, $delimiter2, $match, $replace, $matchtype = 0)
    {
        $offset = 0;
        $mlen = strlen($match);
        while (($srcs = strpos($data, $delimiter1, $offset)) !== false)
        {
            $next2 = $srcs + strlen($delimiter1);
            $next = $next2 - 1;
            if (($srct = strpos($data, $delimiter2, $next2)) !== false)
            {
                $sample = substr($data, $next2, $srct - $next2);
                $matched = (($matchtype === 0) && ($sample == $match));
                $matched = (($matchtype === 1) && (substr($sample, 0, $mlen)  == $match));
                $matched = (($matchtype === 2) && (substr($sample, $mlen)  == $match));
                $matched = (($matchtype === 3) && (strpos($sample, $match) !== false));
                if ($matched)
                {
                    $data = substr($data, 0, $next2).$replace.substr($data, $srct);
                    $offset = $srct + 1;
                }
                else
                {
                    $offset = $next2;
                }
            }
            else
            {
                $offset = $next2;
            }
        }
        return $data;
    }

    protected function _build_message()
    {
        if ($this->wordwrap === TRUE  AND  $this->mailtype != 'html')
        {
            $this->_body = $this->word_wrap($this->_body);
        }

        $this->_set_boundaries();
        $this->_write_headers();

        $hdr = ($this->_get_protocol() == 'mail') ? $this->newline : '';
        $body = '';

        switch ($this->_get_content_type())
        {
            case 'plain' :

                $hdr .= "Content-Type: text/plain; charset=" . $this->charset . $this->newline;
                $hdr .= "Content-Transfer-Encoding: " . $this->_get_encoding();

                if ($this->_get_protocol() == 'mail')
                {
                    $this->_header_str .= $hdr;
                    $this->_finalbody = $this->_body;
                }
                else
                {
                    $this->_finalbody = $hdr . $this->newline . $this->newline . $this->_body;
                }

                return;

            break;
            case 'html' :

                if ($this->send_multipart === FALSE)
                {
                    $hdr .= "Content-Type: text/html; charset=" . $this->charset . $this->newline;
                    $hdr .= "Content-Transfer-Encoding: quoted-printable";
                }
                else
                {
                    $hdr .= "Content-Type: multipart/alternative; boundary=\"" . $this->_alt_boundary . "\"" . $this->newline . $this->newline;

                    $body .= $this->_get_mime_message() . $this->newline . $this->newline;
                    $body .= "--" . $this->_alt_boundary . $this->newline;

                    $body .= "Content-Type: text/plain; charset=" . $this->charset . $this->newline;
                    $body .= "Content-Transfer-Encoding: " . $this->_get_encoding() . $this->newline . $this->newline;
                    $body .= $this->_get_alt_message() . $this->newline . $this->newline . "--" . $this->_alt_boundary . $this->newline;

                    $body .= "Content-Type: text/html; charset=" . $this->charset . $this->newline;
                    $body .= "Content-Transfer-Encoding: quoted-printable" . $this->newline . $this->newline;
                }

                $this->_finalbody = $body . $this->_prep_quoted_printable($this->_body) . $this->newline . $this->newline;


                if ($this->_get_protocol() == 'mail')
                {
                    $this->_header_str .= $hdr;
                }
                else
                {
                    $this->_finalbody = $hdr . $this->_finalbody;
                }


                if ($this->send_multipart !== FALSE)
                {
                    $this->_finalbody .= "--" . $this->_alt_boundary . "--";
                }

                return;

            break;
            case 'plain-attach' :

                $hdr .= "Content-Type: multipart/".$this->multipart."; boundary=\"" . $this->_atc_boundary."\"" . $this->newline . $this->newline;

                if ($this->_get_protocol() == 'mail')
                {
                    $this->_header_str .= $hdr;
                }

                $body .= $this->_get_mime_message() . $this->newline . $this->newline;
                $body .= "--" . $this->_atc_boundary . $this->newline;

                $body .= "Content-Type: text/plain; charset=" . $this->charset . $this->newline;
                $body .= "Content-Transfer-Encoding: " . $this->_get_encoding() . $this->newline . $this->newline;

                $body .= $this->_body . $this->newline . $this->newline;

            break;
            case 'html-attach' :

                $hdr .= "Content-Type: multipart/".$this->multipart."; boundary=\"" . $this->_atc_boundary."\"" . $this->newline . $this->newline;

                if ($this->_get_protocol() == 'mail')
                {
                    $this->_header_str .= $hdr;
                }

                $body .= $this->_get_mime_message() . $this->newline . $this->newline;
                $body .= "--" . $this->_atc_boundary . $this->newline;

                $body .= "Content-Type: multipart/alternative; boundary=\"" . $this->_alt_boundary . "\"" . $this->newline .$this->newline;
                $body .= "--" . $this->_alt_boundary . $this->newline;

                $body .= "Content-Type: text/plain; charset=" . $this->charset . $this->newline;
                $body .= "Content-Transfer-Encoding: " . $this->_get_encoding() . $this->newline . $this->newline;
                $body .= $this->_get_alt_message() . $this->newline . $this->newline . "--" . $this->_alt_boundary . $this->newline;

                $body .= "Content-Type: text/html; charset=" . $this->charset . $this->newline;
                $body .= "Content-Transfer-Encoding: quoted-printable" . $this->newline . $this->newline;

                $body .= $this->_prep_quoted_printable($this->_body) . $this->newline . $this->newline;
                $body .= "--" . $this->_alt_boundary . "--" . $this->newline . $this->newline;

            break;
        }

        $attachment = array();

        $z = 0;

        for ($i=0; $i < count($this->_attach_name); $i++)
        {
            $filename = $this->_attach_name[$i];
            $basename = basename($filename);
            $ctype = $this->_attach_type[$i];

            if ( ! file_exists($filename))
            {
                $this->_set_error_message('lang:email_attachment_missing', $filename);
                return FALSE;
            }

            $h  = "--".$this->_atc_boundary.$this->newline;
            $h .= "Content-type: ".$ctype."; ";
            $h .= "name=\"".$basename."\"".$this->newline;
            $h .= "Content-Disposition: ".$this->_attach_disp[$i].";".$this->newline;
            $h .= "Content-Transfer-Encoding: base64".$this->newline;

            if ($this->_attach_disp[$i] == 'inline')
            {
                $cid = 'inl_'.$i;
                $cid1 = 'cid:'.$cid;
                $h .= "Content-ID: <".$cid.">".$this->newline;
                $body = $this->matched_replace_between($body, 'src=3D"', '"', $filename, $cid1, 3);
                $body = $this->matched_replace_between($body, 'href=3D"', '"', $filename, $cid1, 3);
                $body = $this->matched_replace_between($body, 'src="', '"', $filename, $cid1, 3);
                $body = $this->matched_replace_between($body, 'href="', '"', $filename, $cid1, 3);
                $body = $this->matched_replace_between($body, 'url(\'', '\');', $filename, $cid1, 3);
            }

            $attachment[$z++] = $h;
            $file = filesize($filename) +1;

            if ( ! $fp = fopen($filename, FOPEN_READ))
            {
                $this->_set_error_message('lang:email_attachment_unreadable', $filename);
                return FALSE;
            }

            $attachment[$z++] = chunk_split(base64_encode(fread($fp, $file)));
            fclose($fp);
        }

        $body .= implode($this->newline, $attachment).$this->newline."--".$this->_atc_boundary."--";


        if ($this->_get_protocol() == 'mail')
        {
            $this->_finalbody = $body;
        }
        else
        {
            $this->_finalbody = $hdr . $body;
        }

        return;
    }
}