be clever about extensions on upload

This patch makes it possible to enter filenames without an
extension in the upload as field when the uploaded file it
self has a known extension.

It also prints a warning when an extension was changed by
the user.

darcs-hash:20060527100310-7ad00-cf2abb4b9730e54b96c6ba24b2a999011cfb834a.gz

inc/lang/en/lang.php

@@ -109,6 +109,7 @@ $lang['mediausage']  = 'Use the following syntax to reference this file:';
 $lang['mediaview']   = 'View original file';
 $lang['mediaroot']   = 'root';
 $lang['mediaupload'] = 'Upload a file to the current namespace here. To create subnamespaces, prepend them to your "Upload as" filename separated by colons.';
+$lang['mediaextchange'] = 'Filextension changed from .%s to .%s!';
 
 $lang['reference']   = 'References for';
 $lang['ref_inuse']   = 'The file can\'t be deleted, because it\'s still used by the following pages:';

inc/media.php

@@ -185,13 +185,24 @@ function media_upload($ns,$auth){
     global $lang;
     global $conf;
 
-    // get file
+    // get file and id
     $id   = $_POST['id'];
     $file = $_FILES['upload'];
-    // get id
     if(empty($id)) $id = $file['name'];
-    $id   = cleanID($ns.':'.$id);  //FIXME handle relative and absolute names here
+
+    // check extensions
+    list($fext) = mimetype($file['name']);
+    list($iext) = mimetype($id);
+    if($fext && !$iext){
+        // no extension specified in id - readd original one
+        $id .= '.'.$fext;
+    }elseif($fext && $fext != $iext){
+        // extension was changed, print warning
+        msg(sprintf($lang['mediaextchange'],$fext,$iext));
+    }
+
     // get filename
+    $id   = cleanID($ns.':'.$id);
     $fn   = mediaFN($id);
 
     // get filetype regexp