Adding e-mail notifications about mentions, follows, favourites and reblogs. Fixing another mention recording bug

app/mailers/application_mailer.rb

@@ -0,0 +1,4 @@
+class ApplicationMailer < ActionMailer::Base
+  default from: (ENV['SMTP_FROM_ADDRESS'] || 'notifications@localhost')
+  layout 'mailer'
+end

app/mailers/notification_mailer.rb

@@ -0,0 +1,34 @@
+class NotificationMailer < ApplicationMailer
+  helper StreamEntriesHelper
+  helper AtomBuilderHelper
+
+  def mention(mentioned_account, status)
+    @me     = mentioned_account
+    @status = status
+
+    mail to: @me.user.email, subject: "You were mentioned by #{@status.account.acct}"
+  end
+
+  def follow(followed_account, follower)
+    @me      = followed_account
+    @account = follower
+
+    mail to: @me.user.email, subject: "#{@account.acct} is now following you"
+  end
+
+  def favourite(target_status, from_account)
+    @me      = target_status.account
+    @account = from_account
+    @status  = target_status
+
+    mail to: @me.user.email, subject: "#{@account.acct} favourited your status"
+  end
+
+  def reblog(target_status, from_account)
+    @me      = target_status.account
+    @account = from_account
+    @status  = target_status
+
+    mail to: @me.user.email, subject: "#{@account.acct} reblogged your status"
+  end
+end