removing more logic from templates + simpler coffeescript

app/assets/javascripts/inbox.coffee

@@ -9,10 +9,10 @@
       if data.success
         ($ "div#entries").prepend(data.render) # TODO: slideDown or something
         # GitHub issue #26:
-        if document.getElementById('ib-delete-all') == undefined
-          del_all_btn = ($ "button#ib-delete-all-author")
-        else
+        if document.getElementById('ib-delete-all')?
           del_all_btn = ($ "button#ib-delete-all")
+        else
+          del_all_btn = ($ "button#ib-delete-all-author")
         del_all_btn.removeAttr 'disabled'
         del_all_btn[0].dataset.ibCount = (Number del_all_btn[0].dataset.ibCount) + 1
     error: (jqxhr, status, error) ->
@@ -163,10 +163,10 @@ $(document).on "click", "button[name=ib-destroy]", ->
       success: (data, status, jqxhr) ->
         if data.success
           $("div.inbox-box[data-id=#{iid}]").slideUp()
-          if document.getElementById('ib-delete-all') == undefined
-            del_all_btn = ($ "button#ib-delete-all-author")
-          else
+          if document.getElementById('ib-delete-all')?
             del_all_btn = ($ "button#ib-delete-all")
+          else
+            del_all_btn = ($ "button#ib-delete-all-author")
           del_all_btn.removeAttr 'disabled'
           del_all_btn[0].dataset.ibCount = (Number del_all_btn[0].dataset.ibCount) - 1
         showNotification data.message, data.success

app/controllers/inbox_controller.rb

@@ -26,10 +26,13 @@ class InboxController < ApplicationController
         end
       rescue
         flash.now[:error] = "No user with the name @#{params[:author]} found, showing default entries instead!"
+        @not_found = true
         @inbox
         @inbox_count
       end
     end
+
+    @disabled = true if @inbox.empty? or @not_found
     respond_to do |format|
       format.html
       format.js

app/views/inbox/_sidebar.html.haml

@@ -25,5 +25,5 @@
   .panel-heading
     %h3.panel-title= t 'views.inbox.sidebar.actions.title'
   .panel-body
-    %button.btn.btn-block.btn-danger{type: :button, id: @author ? 'ib-delete-all-author' : 'ib-delete-all', disabled: (Inbox.where(user: current_user).empty? ? 'disabled' : nil), data: { ib_count: @inbox_count }}= t 'views.inbox.sidebar.actions.button'
+    %button.btn.btn-block.btn-danger{type: :button, id: @author ? 'ib-delete-all-author' : 'ib-delete-all', disabled: (@disabled ? 'disabled' : nil), data: { ib_count: @inbox_count }}= t 'views.inbox.sidebar.actions.button'