Provide '--' message for empty messages

Provide fallback html2text mechanism if PHP xml extension is not available

include/class.mailfetch.php

@@ -421,22 +421,28 @@ class MailFetcher {
         if ($cfg->isHtmlThreadEnabled()) {
             if ($body=$this->getPart($mid, 'text/html', $this->charset)) {
                 //Cleanup the html.
-                $body=Format::safe_html($body); //Balance html tags & neutralize unsafe tags.
+                $body = (trim($body, " <>br/\t\n\r"))
+                    ? Format::safe_html($body)
+                    : '--';
             }
             elseif ($body=$this->getPart($mid, 'text/plain', $this->charset)) {
-                $body = Format::htmlchars($body);
-                $body = "<div style=\"white-space:pre-wrap\">$body</div>";
+                $body = trim($body)
+                    ? sprintf('<div style="white-space:pre-wrap">%s</div>',
+                        Format::htmlchars($body))
+                    : '--';
             }
         }
         else {
             if ($body=$this->getPart($mid, 'text/plain', $this->charset)) {
-                //Cleanup the html.
                 $body = Format::htmlchars($body);
-                $body = "<div style=\"white-space:pre-wrap\">$body</div>";
             }
             elseif ($body=$this->getPart($mid, 'text/html', $this->charset)) {
-                $body = convert_html_to_text($body, 100);
+                $body = convert_html_to_text(Format::safe_html($body), 100);
             }
+            $body = trim($body)
+                ? sprintf('<div style="white-space:pre-wrap">%s</div>',
+                    $body)
+                : '--';
         }
         return $body;
     }

include/class.mailparse.php

@@ -160,23 +160,29 @@ class Mail_Parse {
 
         if ($cfg->isHtmlThreadEnabled()) {
             if ($body=$this->getPart($this->struct,'text/html')) {
-                //Cleanup the html.
-                $body=Format::safe_html($body); //Balance html tags & neutralize unsafe tags.
+                // Cleanup the html -- Balance html tags & neutralize unsafe tags.
+                $body = (trim($body, " <>br/\t\n\r"))
+                    ? Format::safe_html($body)
+                    : '--';
             }
             elseif ($body=$this->getPart($this->struct,'text/plain')) {
-                $body = Format::htmlchars($body);
-                $body = "<div style=\"white-space:pre-wrap\">$body</div>";
+                $body = trim($body)
+                    ? sprintf('<div style="white-space:pre-wrap">%s</div>',
+                        Format::htmlchars($body))
+                    : '--';
             }
         }
         else {
             if ($body=$this->getPart($this->struct,'text/plain')) {
-                //Cleanup the html.
                 $body = Format::htmlchars($body);
-                $body = "<div style=\"white-space:pre-wrap\">$body</div>";
             }
             elseif ($body=$this->getPart($this->struct,'text/html')) {
                 $body = convert_html_to_text($body, 100);
             }
+            $body = trim($body)
+                ? sprintf('<div style="white-space:pre-wrap">%s</div>',
+                    $body)
+                : '--';
         }
         return $body;
     }

include/html2text.php

@@ -27,6 +27,9 @@
 function convert_html_to_text($html, $width=74) {
     $html = fix_newlines($html);
 
+    if (!extension_loaded('xml'))
+        return strip_tags($html);
+
     $doc = new DOMDocument('1.0', 'utf-8');
     if (!@$doc->loadHTML($html))
         return $html;