add topic moving option for mods

views/threads/thread.etlua

@@ -25,6 +25,15 @@
           <input type=hidden value="<%= not is_stickied %>" name="target_op">
           <input class="warn" type="submit" value="<%= is_stickied and "Unsticky thread" or "Sticky thread" %>">
         </form>
+        <form class="modform" action="<%= url_for("thread_move", {slug = thread.slug}) %>" method="post">
+          <label for="new_topic_id">Move to topic:</label>
+          <select style="width:200px;" id="new_topic_id" name="new_topic_id" autocomplete="off">
+            <% for _, topic in ipairs(other_topics) do %>
+              <option value="<%= topic.id %>" <%- thread.topic_id == topic.id and "selected disabled" or "" %>><%= topic.name %></option>
+            <% end %>
+          </select>
+          <input class="warn" type="submit" value="Move thread">
+        </form>
       <% end %>
     </div>
     <% end %>