allow embedded images in story text, but still not in comments

app/models/story.rb

@@ -251,7 +251,7 @@ class Story < ActiveRecord::Base
   end
 
   def generated_markeddown_description
-    Markdowner.to_html(self.description)
+    Markdowner.to_html(self.description, allow_images = true)
   end
 
   def description=(desc)

app/views/global/_markdownhelp.html.erb

@@ -27,5 +27,14 @@
   text</pre></td>
     <td>prefix text with at least <tt>&nbsp;&nbsp;&nbsp;3 spaces</tt></td>
   </tr>
+
+  <% if defined?(allow_images) && allow_images %>
+    <tr>
+      <td>(inline image)</td>
+      <td><tt>![alt text](http://example.com/image.jpg)</tt> (only allowed in
+        story text</td>
+    </tr>
+  <% end %>
+
   </table>
 </div>

app/views/stories/edit.html.erb

@@ -32,7 +32,8 @@
 
         <div style="clear: both;"></div>
 
-        <%= render :partial => "global/markdownhelp" %>
+        <%= render :partial => "global/markdownhelp",
+          :locals => { :allow_images => true } %>
       </div>
     </div>
 	<% end %>

app/views/stories/new.html.erb

@@ -85,7 +85,8 @@
 
           <div style="clear: both;"></div>
 
-          <%= render :partial => "global/markdownhelp" %>
+          <%= render :partial => "global/markdownhelp",
+            :locals => { :allow_images => true } %>
         </div>
       </div>
     <% end %>

extras/markdowner.rb

@@ -1,10 +1,11 @@
 class Markdowner
-  def self.to_html(text)
+  def self.to_html(text, allow_images = false)
     if text.blank?
       return ""
     else
-      html = RDiscount.new(text.to_s, :smart, :autolink, :safelink,
-        :filter_styles, :filter_html, :no_image).to_html
+      html = RDiscount.new(text.to_s, *[ :smart, :autolink, :safelink,
+        :filter_styles, :filter_html ] + (allow_images ? [] : [ :no_image ])).
+        to_html
 
       # change <h1> headings to just emphasis tags
       html.gsub!(/<(\/)?h(\d)>/) {|_| "<#{$1}strong>" }