class Poll < ActiveRecord::Base
  has_many :choices, :dependent => :destroy
  validates_presence_of :question
  validates_presence_of :post
  has_many :votes, :dependent => :destroy
  belongs_to :post
      
  def voted?(user)
    !self.votes.find_by_user_id(user.id).nil?
  end
  
  def add_choices(choices)
    choices.each do |description|
      choice = self.choices.new(:description => description)
      choice.save
    end
  end

  def self.find_recent(options = {})
    options.reverse_merge! :limit => 5
    self.includes(:post => :user).order("polls.created_at desc").limit(options[:limit])
  end

  def self.find_popular(options = {})
    options.reverse_merge! :limit => 5, :since => 10.days.ago

    self.includes(:post => :user)
      .where("polls.created_at > ?", options[:since])
      .order("polls.votes_count desc")
      .limit(options[:limit])
  end

  def self.find_popular_in_category(category, options = {})
    options.reverse_merge! :limit => 5
    self.includes(:post).order('polls.votes_count desc').where('posts.category_id = ?', category.id).references(:posts).limit(options[:limit])
  end

end