drop down to binary if UTF fails, don't conduct any replacing of characters

app.rb

@@ -579,3 +579,12 @@ end
 def template_site_title(username)
   "#{username.capitalize}#{username[username.length-1] == 's' ? "'" : "'s"} Site"
 end
+
+def encoding_fix(file)
+  begin
+    Rack::Utils.escape_html file
+  rescue ArgumentError => e
+    return Rack::Utils.escape_html(file.force_encoding('BINARY')) if e.message =~ /invalid byte sequence in UTF-8/
+    fail
+  end
+end

views/site_files/text_editor.slim

@@ -56,7 +56,7 @@ css:
     .row
       .span12
         div id="editor" style="width: 100%; height: 600px; position: relative;"
-          #{@file_data}
+          == encoding_fix @file_data
     
     
     .row