service_objects_bp_6.rb

class CommentsController
  def create
    comment = Comment.new(params[:comment])
    @comment = CommentCreator.new(comment).create!
    respond_with @comment
  end
end

class CommentCreator
  def initialize(comment)
    @comment = comment
  end

  def create!
    @comment.save!
    CommentCreatedWorker.perform_async(@comment.id)
    @comment
  end

  def perform
    ThreadParticipantsNotifier.new(@comment).notify
    CommentReplyNotifier.new(@comment).notify
    Kissmetrics.record(@comment.author, 'Added Comment')
  end
end

class CommentCreatedWorker
  include Sidekiq::Worker

  def perform(comment_id)
    comment = Comment.find(comment_id)
    CommentCreator.new(comment).perform
  end
end

class ThreadParticipantsNotifier
  def initialize(comment)
    @comment = comment
  end

  def notify
    participants.each { |participant| notify_participant(participant) }
  end

  def notify_participant(participant)
    CommentThreadMailer.activity_notification(comment_thread, @comment, participant)
  end

  private

  def participants
    comment_thread.participants
  end

  def comment_thread
    @comment.comment_thread
  end
end

class CommentReplyNotifier
  def initialize(comment)
    @comment = comment
  end

  def notify
    if previous_comment?
      ReplyMailer.notification(in_reply_to_user, @comment).deliver
    end
  end

  private

  def previous_comment?
    !!previous_comment
  end

  def previous_comment
    @comment.previous_comment
  end

  def in_reply_to_user
    previous_comment.author
  end
end