--- a/app/controllers/browse_controller.rb
+++ b/app/controllers/browse_controller.rb
@@ -25,6 +25,7 @@ class BrowseController < ApplicationController
   end
   
   def commit
+    @diffmode = params[:diffmode] == "sidebyside" ? "sidebyside" : "inline"
     @git = Git.bare(@repository.full_repository_path)
     @commit = @git.gcommit(params[:sha])
     if @commit.parent

--- a/app/helpers/browse_helper.rb
+++ b/app/helpers/browse_helper.rb
@@ -37,12 +37,20 @@ module BrowseHelper
   end  
   
   # Takes a unified diff as input and renders it as html
-  def render_diff(udiff, src_sha, dst_sha)
+  def render_diff(udiff, src_sha, dst_sha, display_mode = "inline")
     return if udiff.blank?
-    
+
+    case display_mode
+    when "sidebyside"
+      render_sidebyside_diff(udiff, src_sha, dst_sha)
+    else
+      render_inline_diff(udiff, src_sha, dst_sha)
+    end
+  end
+  
+  def render_inline_diff(udiff, src_sha, dst_sha)
     callback = Gitorious::Diff::InlineTableCallback.new
-    
-    out = %Q{<table class="codediff">\n}
+    out = %Q{<table class="codediff inline">\n}
     out << "<thead>\n"
     out << "<tr>"
     out << %Q{<td class="line-numbers">#{src_sha}</td>}
@@ -54,4 +62,16 @@ module BrowseHelper
     out
   end
   
+  def render_sidebyside_diff(udiff, src_sha, dst_sha)
+    callback = Gitorious::Diff::SidebysideTableCallback.new
+    out = %Q{<table class="codediff sidebyside">\n}
+    out << %Q{<colgroup class="left"><col class="lines"/><col class="code"/></colgroup>}
+    out << %Q{<colgroup class="right"><col class="lines"/><col class="code"/></colgroup>}
+    out << %Q{<thead><th colspan="2">#{src_sha}</th>}
+    out << %Q{<th colspan="2">#{dst_sha}</th></thead>}
+    out << Diff::Display::Unified::Renderer.run(udiff, callback)
+    out << "</table>"
+    out
+  end
+  
 end

--- a/app/views/browse/commit.html.erb
+++ b/app/views/browse/commit.html.erb
@@ -13,10 +13,11 @@
 <% #TODO: commit diff stats (as sparklines?) -%>
 
 <h2>Commit diff</h2>
+<% #TODO diffmode selector -%>
 
 <% @diff.each do |file| -%>
   <h4><%= h(file.path) -%><%#=link_to h(file.path), blob_path(file.sha, file.path) -%></h4>
-  <%= render_diff(file.patch, file.src, file.dst) -%>
+  <%= render_diff(file.patch, file.src, file.dst, @diffmode) -%>
   <small><%= link_to_function "toggle raw diff", "$('#{file.id}').toggle()" -%></small>
   <div class="toggle_diff" style="display:none" id="<%= file.id -%>">
   <p><pre><%=  h(file.patch) -%></pre></p>

--- a/db/schema.rb
+++ b/db/schema.rb
@@ -48,9 +48,9 @@ ActiveRecord::Schema.define(:version => 19) do
     t.string   "bugtracker_url"
   end
 
+  add_index "projects", ["slug"], :name => "index_projects_on_slug", :unique => true
   add_index "projects", ["title"], :name => "index_projects_on_name"
   add_index "projects", ["user_id"], :name => "index_projects_on_user_id"
-  add_index "projects", ["slug"], :name => "index_projects_on_slug"
 
   create_table "repositories", :force => true do |t|
     t.string   "name"
@@ -93,6 +93,8 @@ ActiveRecord::Schema.define(:version => 19) do
     t.string "name"
   end
 
+  add_index "tags", ["name"], :name => "index_tags_on_name", :unique => true
+
   create_table "tasks", :force => true do |t|
     t.string   "target_class"
     t.string   "command"

--- /dev/null
+++ b/lib/gitorious/diff/sidebyside_table_callback.rb
@@ -0,0 +1,112 @@
+module Gitorious
+  module Diff
+    class SidebysideTableCallback
+      
+      # Before blocks
+      def before_addblock(block)
+        "<tbody><tr>"
+      end
+      
+      def before_remblock(block) 
+        "<tbody><tr>"
+      end
+      
+      def before_modblock(block)
+        "<tbody><tr>"
+      end
+      
+      def before_unmodblock(block)
+        "<tbody><tr>"
+      end
+      
+      def before_sepblock(block)
+        "<tbody><tr>"
+      end
+      
+      # After blocks
+      def after_addblock(block)
+        "</tbody>"
+      end
+      
+      def after_remblock(block)
+        "</tbody>"
+      end
+      
+      def after_modblock(block)
+        # "</tbody>"
+      end
+      
+      def after_unmodblock(block)
+        "</tbody>"
+      end
+      
+      def after_sepblock(block)
+        "</body>"
+      end
+      
+      # Before lines
+      def before_addline(line)
+        # adds go on the right
+        %Q{<th class="line-numbers">#{line.number}</th>} + 
+        %Q{<td class="code ins"></td>} + 
+        %Q{<th class="line-numbers">#{line.number}</th>} + 
+        %Q{<td class="code ins"><ins>}
+      end
+      
+      def before_remline(line)
+        # rems go on the left (hide the right side)
+        %Q{<th class="line-numbers">#{line.number}</th>} + 
+        %Q{<td class="code del"><del>#{line}</del></td>} + 
+        %Q{<th class="line-numbers">#{line.number}</th>} + 
+        %Q{<td class="code del hidden"><del>}
+      end
+      
+      def before_modline(line)
+        # TODO: figure how we best display these
+        # %Q{<th class="line-numbers">#{line.number}</th>} + 
+        # %Q{<td class="code changed mod">#{line}</td>} + 
+        # %Q{<th class="line-numbers">#{line.number}</th>} + 
+        # %Q{<td class="code changed mod">}
+      end
+      
+      def before_unmodline(line)
+        # unmods goes on both sides
+        %Q{<th class="line-numbers">#{line.number}</th>} + 
+        %Q{<td class="code unchanged unmod">#{line}</td>} + 
+        %Q{<th class="line-numbers">#{line.number}</th>} + 
+        %Q{<td class="code unchanged unmod">}
+      end
+      
+      def before_sepline(line)
+        %Q{<th class="line-numbers line-num-cut">...</th>} + 
+        %Q{<td class="code cut-line">...</td>} + 
+        %Q{<th class="line-numbers line-num-cut">...</th>} + 
+        %Q{<td class="code cut-line">}
+      end
+      
+      # After lines
+      def after_addline(line)
+        "</ins></td></tr>"
+      end
+      
+      def after_remline(line)
+        "</del></td></tr>"
+      end
+      
+      def after_modline(line)
+        # "</td></tr>"
+      end
+      
+      def after_unmodline(line)
+        "</td></tr>"
+      end
+      
+      def after_sepline(line)
+        "</td></tr>"
+      end
+      
+      def new_line
+      end
+    end
+  end
+end
\ No newline at end of file

--- a/public/stylesheets/base.css
+++ b/public/stylesheets/base.css
@@ -553,7 +553,7 @@ div.comment p.byline {
   
 }
 
-table tr td.line-numbers {
+table tr .line-numbers {
  text-align: right;
  vertical-align: top;
  background: #eee;
@@ -572,6 +572,13 @@ table tr td.code {
  font: 100%/110%  "Courier New", Courier, monaco, monospace;
 }
 
+table.sidebyside {
+  empty-cells: show;
+  table-layout: fixed;
+}
+table.sidebyside tr td.code {
+  white-space: normal;
+}
 
 table.codediff {
   border: 1px solid #ccc;
@@ -580,19 +587,24 @@ table.codediff {
   font-family: monospace;
   line-height: 90%;
 }
-table.codediff td.line-num-cut { 
+table.codediff .line-num-cut { 
   background: #ccc; 
   border-top: 1px dashed #ccc; 
   border-bottom: 1px dashed #ccc; 
 }
-table.codediff thead td.line-numbers, table.codediff thead { background: #ddd; }
+
+table.codediff thead .line-numbers, table.codediff thead { background: #ddd; }
 table.codediff td.code { padding-left: 2px; }
-table.codediff td.cut-line { 
+table.codediff .cut-line { 
   background: #eee; 
   border-top: 1px dashed #aaa; 
   border-bottom: 1px dashed #aaa; 
 }
+table.codediff td.hidden del { display:none; }
 table.codediff td.del { background: #fdd; }
 table.codediff td.ins { background: #dfd; }
 table.codediff td.del del { /*background: #fbb;*/ text-decoration: none; }
 table.codediff td.ins ins { /*background: #afa;*/ text-decoration: none; }
+table.codediff col.lines {
+  width: 3em;
+}
\ No newline at end of file