diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..4ebc8ae
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1 @@
+coverage
diff --git a/Gemfile b/Gemfile
new file mode 100644
index 0000000..89a0edb
--- /dev/null
+++ b/Gemfile
@@ -0,0 +1,3 @@
+group :test do
+  gem 'simplecov', '~> 0.6'
+end
diff --git a/Rakefile b/Rakefile
deleted file mode 100644
index ffa56e9..0000000
--- a/Rakefile
+++ /dev/null
@@ -1,12 +0,0 @@
-require 'rake'
-require 'rake/testtask'
-
-desc "Default: run unit tests."
-task :default => :test
-
-desc "Test the redmine_tagging plugin."
-Rake::TestTask.new(:test) do |t|
-  t.libs << 'lib'
-  t.pattern = 'test/**/*_test.rb'
-  t.verbose = true
-end
diff --git a/app/views/attachments/_links.html.erb b/app/views/attachments/_links.html.erb
index c9b6872..04cdafa 100644
--- a/app/views/attachments/_links.html.erb
+++ b/app/views/attachments/_links.html.erb
@@ -1,12 +1,11 @@
-<div class="attachments can_preview">
+<div class="attachments">
 <% for attachment in attachments %>
-<p>
+<p><%= link_to_attachment_with_preview attachment, :class => 'icon icon-attachment', :download => true -%>
   <%= h(" - #{attachment.description}") unless attachment.description.blank? %>
   <span class="size">(<%= number_to_human_size attachment.filesize %>)</span>
-  <%= link_to_attachment_with_preview(attachment, :class => 'icon icon-attachment') %>
   <% if options[:deletable] %>
     <%= link_to image_tag('delete.png'), attachment_path(attachment),
-                                         :confirm => l(:text_are_you_sure),
+                                         :data => {:confirm => l(:text_are_you_sure)},
                                          :method => :delete,
                                          :class => 'delete',
                                          :title => l(:button_delete) %>
@@ -16,18 +15,15 @@
   <% end %>
   </p>
 <% end %>
-
-<% if Setting.plugin_redmine_lightbox['preview_image_attachments'] %>
-  <% images = attachments.select { |a| a.image? } %>
-  <% unless images.empty? %>
-    <div class='images'>
-      <% images.each do |attachment| %>
-        <%= link_to image_tag(url_for({:controller => 'attachments', :action => 'show', :id => attachment, :filename => attachment.filename }), :class => 'image_attachment_preview'),
-        {:controller => 'attachments', :action => 'show', :id => attachment, :filename => attachment.filename }, :class => 'lightbox', :rel => 'attachments', :title => "#{attachment.filename}#{ ('-' + attachment.description) unless attachment.description.blank? }" %>
-      <% end -%>
-    </div>
+<% if defined?(thumbnails) && thumbnails %>
+  <% images = attachments.select(&:thumbnailable?) %>
+  <% if images.any? %>
+  <div class="thumbnails">
+    <% images.each do |attachment| %>
+      <div><%= thumbnail_tag(attachment) %></div>
+    <% end %>
+  </div>
   <% end %>
 <% end %>
-
 </div>
 
diff --git a/app/views/settings/_lightbox_settings.html.erb b/app/views/settings/_lightbox_settings.html.erb
deleted file mode 100644
index 20c63d5..0000000
--- a/app/views/settings/_lightbox_settings.html.erb
+++ /dev/null
@@ -1,10 +0,0 @@
-<fieldset>
-  <p><%= l(:redmine_lightbox_settings) %></p>
-  <p>
-    <label><%= l(:preview_image_attachments)%></label>
-    <%= check_box_tag('settings[preview_image_attachments]',
-                      '1',
-                      @settings['preview_image_attachments'])
-    %>
-  </p>
-</fieldset>
diff --git a/assets/javascripts/jquery_loader.js b/assets/javascripts/jquery_loader.js
deleted file mode 100644
index 7ed7c17..0000000
--- a/assets/javascripts/jquery_loader.js
+++ /dev/null
@@ -1,3 +0,0 @@
-if(typeof jQuery == 'undefined') {
-  document.write('<script type="text/javascript" src="//ajax.googleapis.com/ajax/libs/jquery/1.8.1/jquery.min.js"></script>')
-}
diff --git a/assets/stylesheets/lightbox.css b/assets/stylesheets/lightbox.css
index 20c0aea..6da0bff 100644
--- a/assets/stylesheets/lightbox.css
+++ b/assets/stylesheets/lightbox.css
@@ -1,11 +1,3 @@
-div.attachments div.images
-{
-    border: 1px solid #CCCCCC;
-    padding: 10px;
-    margin: 10px;
-    display: inline-block;
-}
-
 div.attachments .image_attachment_preview {
     width: auto !important;
     width: 180px;
@@ -18,12 +10,6 @@ div.attachments div.images a.lightbox
   margin: 0px 5px;
 }
 
-div.attachments img.preview_button, .journal img.preview_button
-{
-  margin: 0 4px;
-  width: 18px;
-}
-
 embed.chrome {
   box-sizing: border-box;
   width: 100%;
diff --git a/init.rb b/init.rb
index fa46f40..60a032b 100644
--- a/init.rb
+++ b/init.rb
@@ -13,10 +13,4 @@
   version '0.0.1'
   url 'https://github.com/zipme/redmine_lightbox'
   author_url 'https://github.com/zipme/redmine_lightbox'
-
-  default_settings = {
-    'preview_image_attachments' => true
-  }
-
-  settings(:default => default_settings, :partial => 'settings/lightbox_settings')
 end
diff --git a/lib/redmine_lightbox/hooks/view_layouts_base_html_head_hook.rb b/lib/redmine_lightbox/hooks/view_layouts_base_html_head_hook.rb
index 486ba12..92f2c12 100644
--- a/lib/redmine_lightbox/hooks/view_layouts_base_html_head_hook.rb
+++ b/lib/redmine_lightbox/hooks/view_layouts_base_html_head_hook.rb
@@ -8,16 +8,8 @@ def view_layouts_base_html_head(context={})
                                       context[:controller].is_a?(FilesController) ||
                                       context[:controller].is_a?(BoardsController))
 
-          if Redmine::VERSION.to_s.slice(0, 3) < "2.1"
-            jquery_include = javascript_include_tag('jquery_loader.js', :plugin => 'redmine_lightbox') \
-              + javascript_tag("jQuery.noConflict()")
-          else
-            jquery_include = ""
-          end
-
           return stylesheet_link_tag("jquery.fancybox-1.3.4.css", :plugin => "redmine_lightbox", :media => "screen") \
             + stylesheet_link_tag("lightbox.css", :plugin => "redmine_lightbox", :media => "screen") \
-            + jquery_include \
             + javascript_include_tag('jquery.fancybox-1.3.4.pack.js', :plugin => 'redmine_lightbox') \
             + javascript_include_tag('jquery.easing-1.3.pack.js', :plugin => 'redmine_lightbox') \
             + javascript_include_tag('lightbox.js', :plugin => 'redmine_lightbox') \
diff --git a/lib/redmine_lightbox/patches/issues_helper_patch.rb b/lib/redmine_lightbox/patches/issues_helper_patch.rb
index 5935a17..7720106 100644
--- a/lib/redmine_lightbox/patches/issues_helper_patch.rb
+++ b/lib/redmine_lightbox/patches/issues_helper_patch.rb
@@ -3,18 +3,17 @@
 module RedmineLightbox
   module Patches
     module IssuesHelperPatch
-
       def link_to_attachment_with_preview(attachment, options = {})
-        preview_icon = absolute_url(image_path('preview.png', :plugin => :redmine_lightbox))
-        preview_button = image_tag(preview_icon, :class => "preview_button")
-
-        download_link = link_to_attachment_without_preview(attachment, :only_path => false)
+        preview_icon = absolute_asset_url('images/preview.png')
+        icon_style = "width: 18px; margin: 0px 4px"
+        preview_button = image_tag(preview_icon, :style => icon_style)
 
-        if attachment.image? && Setting.plugin_redmine_lightbox['preview_image_attachments']
-          download_link
-        else
-          "#{download_link} #{preview_link_with(attachment, preview_button)}"
+        unless preview_available?(attachment) 
+          return link_to_attachment_without_preview(attachment, options)
         end
+
+        download_link = link_to_attachment_without_preview(attachment, :only_path => false)
+        raw("#{download_link} #{preview_link_with(attachment, preview_button)}")
       end
 
       def show_detail_with_only_path_disabled(detail, no_html = false, options={})
@@ -22,9 +21,28 @@ def show_detail_with_only_path_disabled(detail, no_html = false, options={})
       end
 
       private
+        def absolute_asset_url(asset_url, plugin_asset = true)
+          if plugin_asset
+            paths = [
+              'plugin_assets',
+              'redmine_lightbox',
+              asset_url
+            ]
+            relative_url = File.join(*paths)
+          else
+            relative_url = asset_url
+          end
+
+          "#{home_url}#{relative_url}"
+        end
+
+        def preview_available?(attachment)
+          image = attachment.image?
+          pdf_or_swf = attachment.filename =~ /.(pdf|swf)$/i
+          attachment_preview = attachment.attachment_preview
+          text = attachment.is_text?
 
-        def absolute_url(relative_url)
-          "#{home_url}#{relative_url[1..-1]}"
+          image || text || pdf_or_swf || attachment_preview
         end
 
         def preview_link_with(attachment, preview_button)
@@ -47,7 +65,7 @@ def preview_link_with(attachment, preview_button)
           end
 
           if attachment.is_text?
-            link_to(image_tag(absolute_url(image_path('magnifier.png'))),
+            link_to(image_tag(absolute_asset_url('images/magnifier.png', false)),
               :controller => 'attachments', 
               :action => 'show',
               :id => attachment,
diff --git a/test/functional/issues_controller_test.rb b/test/functional/issues_controller_test.rb
index 43b30f5..4b6f5e2 100644
--- a/test/functional/issues_controller_test.rb
+++ b/test/functional/issues_controller_test.rb
@@ -1,7 +1,8 @@
 require File.dirname(__FILE__) + '/../test_helper'
 
 class IssuesControllerTest < ActionController::TestCase
-  fixtures :issues, :attachments, :users
+  fixtures :issues, :projects, :attachments, :users, :issue_statuses,
+    :enumerations, :trackers
 
   def setup
     set_fixtures_attachments_directory
@@ -9,12 +10,15 @@ def setup
     @some_file = Attachment.find_by_filename("source.rb")
 
     @some_file.create_attachment_preview(:file_type => "pdf")
+
+    @request.session[:user_id] = 2
+    User.stubs(:current).returns(User.find_by_id(2))
+    User.any_instance.stubs(:allowed_to?).returns(true)
   end
 
   def test_should_show_issue_with_attachments_and_previews
-
     @issue_with_file_id = @some_file.container_id
-
+  
     get :show, :id => @issue_with_file_id
     assert_response :success
   end
diff --git a/test/test_helper.rb b/test/test_helper.rb
index 5dc041d..a2972cc 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -1,7 +1,19 @@
 # Load the normal Rails helper
 helper_path = File.expand_path(File.dirname(__FILE__) + '/../../../test/test_helper')
-if !File.exists?(helper_path)
-  helper_path = File.expand_path(File.dirname(__FILE__) + '/../../../../test/test_helper')
+
+plugin_root = File.expand_path(File.dirname(__FILE__) + '/../')
+
+if RUBY_VERSION >= "1.9"
+  require 'simplecov'
+  SimpleCov.start do
+    base_dir = plugin_root
+    root base_dir
+    add_group "Models", "app/models"
+    add_group "Controllers", "app/controllers"
+    add_group "Helpers", "app/helpers"
+    add_group "Views", "app/views"
+    add_group "Lib", "lib"
+  end
 end
 
 require helper_path