post histories finished

app/presenters/post_history_revision_presenter.rb

@@ -0,0 +1,25 @@
+class PostHistoryRevisionPresenter < Presenter
+  attr_reader :revision
+  
+  def initialize(revision)
+    @revision = revision
+  end
+  
+  def changes
+    html =  []
+    html << revision.diff[:del].map {|x| "<del>#{h(x)}</del>"}
+    html << revision.diff[:add].map {|x| "<ins>#{h(x)}</ins>"}
+    html << "<ins>source:#{h(revision.diff[:source])}</ins>" if revision.diff[:source].present?
+    html << "<ins>rating:#{h(revision.diff[:rating])}</ins>" if revision.diff[:rating].present?
+    html << "<ins>parent:#{revision.diff[:parent_id]}</ins>" if revision.diff[:parent_id].present?
+    html.join(" ").html_safe
+  end
+  
+  def updated_at
+    Time.parse(revision.updated_at)
+  end
+  
+  def updater_name
+    User.id_to_name(revision.user_id)
+  end
+end