Add polls (#10111)

* Add polls

Fix #1629

* Add tests

* Fixes

* Change API for creating polls

* Use name instead of content for votes

* Remove poll validation for remote polls

* Add polls to public pages

* When updating the poll, update options just in case they were changed

* Fix public pages showing both poll and other media

app/validators/poll_validator.rb

@@ -0,0 +1,19 @@
+# frozen_string_literal: true
+
+class PollValidator < ActiveModel::Validator
+  MAX_OPTIONS      = 4
+  MAX_OPTION_CHARS = 25
+  MAX_EXPIRATION   = 7.days.freeze
+  MIN_EXPIRATION   = 1.day.freeze
+
+  def validate(poll)
+    current_time = Time.now.utc
+
+    poll.errors.add(:options, I18n.t('polls.errors.too_few_options')) unless poll.options.size > 1
+    poll.errors.add(:options, I18n.t('polls.errors.too_many_options', max: MAX_OPTIONS)) if poll.options.size > MAX_OPTIONS
+    poll.errors.add(:options, I18n.t('polls.errors.over_character_limit', max: MAX_OPTION_CHARS)) if poll.options.any? { |option| option.mb_chars.grapheme_length > MAX_OPTION_CHARS }
+    poll.errors.add(:options, I18n.t('polls.errors.duplicate_options')) unless poll.options.uniq.size == poll.options.size
+    poll.errors.add(:expires_at, I18n.t('polls.errors.duration_too_long')) if poll.expires_at.nil? || poll.expires_at - current_time >= MAX_EXPIRATION
+    poll.errors.add(:expires_at, I18n.t('polls.errors.duration_too_short')) if poll.expires_at.present? && poll.expires_at - current_time <= MIN_EXPIRATION
+  end
+end

app/validators/vote_validator.rb

@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+class VoteValidator < ActiveModel::Validator
+  def validate(vote)
+    vote.errors.add(:base, I18n.t('polls.errors.expired')) if vote.poll.expired?
+
+    if vote.poll.multiple? && vote.poll.votes.where(account: vote.account, choice: vote.choice).exists?
+      vote.errors.add(:base, I18n.t('polls.errors.already_voted'))
+    elsif vote.poll.votes.where(account: vote.account).exists?
+      vote.errors.add(:base, I18n.t('polls.errors.already_voted'))
+    end
+  end
+end