Remove Questionable concern

Since we were only using it in one place, it made the code harder to
follow.

We'll extract it again if we ever find a way to reuse it.

app/models/poll/question.rb

@@ -1,7 +1,6 @@
 class Poll::Question < ApplicationRecord
   include Measurable
   include Searchable
-  include Questionable
 
   acts_as_paranoid column: :hidden_at
   include ActsAsParanoidAliases
@@ -19,6 +18,7 @@ class Poll::Question < ApplicationRecord
            inverse_of: :question,
            dependent: :destroy
   has_many :partial_results
+  has_one :votation_type, as: :questionable, dependent: :destroy
   belongs_to :proposal
 
   validates_translation :title, presence: true, length: { minimum: 4 }
@@ -26,6 +26,9 @@ class Poll::Question < ApplicationRecord
   validates :poll_id, presence: true, if: proc { |question| question.poll.nil? }
 
   accepts_nested_attributes_for :question_options, reject_if: :all_blank, allow_destroy: true
+  accepts_nested_attributes_for :votation_type
+
+  delegate :max_votes, :multiple?, :vote_type, to: :votation_type, allow_nil: true
 
   scope :by_poll_id,    ->(poll_id) { where(poll_id: poll_id) }
 
@@ -82,4 +85,25 @@ class Poll::Question < ApplicationRecord
   def options_with_read_more
     question_options.select(&:with_read_more?)
   end
+
+  def unique?
+    votation_type.nil? || votation_type.unique?
+  end
+
+  def find_or_initialize_user_answer(user, title)
+    answer = answers.find_or_initialize_by(find_by_attributes(user, title))
+    answer.answer = title
+    answer
+  end
+
+  private
+
+    def find_by_attributes(user, title)
+      case vote_type
+      when "unique", nil
+        { author: user }
+      when "multiple"
+        { author: user, answer: title }
+      end
+    end
 end