Add: #348 新規登録の上限人数 (#527)

* Add: #348 新規登録の上限人数

* Fix test

* Fix test

* Wip

* Fix test

* Add invite support

* Wip

* Fix test

* Fix test

* Fix test

app/helpers/registration_helper.rb

@@ -3,8 +3,10 @@
 module RegistrationHelper
   extend ActiveSupport::Concern
 
+  include RegistrationLimitationHelper
+
   def allowed_registration?(remote_ip, invite)
-    !Rails.configuration.x.single_user_mode && !omniauth_only? && (registrations_open? || invite&.valid_for_use?) && !ip_blocked?(remote_ip)
+    !Rails.configuration.x.single_user_mode && !omniauth_only? && ((registrations_open? && !reach_registrations_limit?) || invite&.valid_for_use?) && !ip_blocked?(remote_ip)
   end
 
   def registrations_open?

app/helpers/registration_limitation_helper.rb

@@ -0,0 +1,55 @@
+# frozen_string_literal: true
+
+module RegistrationLimitationHelper
+  def reach_registrations_limit?
+    return true unless registrations_in_time?
+
+    ((Setting.registrations_limit.presence || 0).positive? && Setting.registrations_limit <= user_count_for_registration) ||
+      ((Setting.registrations_limit_per_day.presence || 0).positive? && Setting.registrations_limit_per_day <= today_increase_user_count)
+  end
+
+  def user_count_for_registration
+    Rails.cache.fetch('registrations:user_count') { User.confirmed.enabled.joins(:account).merge(Account.without_suspended).count }
+  end
+
+  def today_increase_user_count
+    today_date = Time.now.utc.beginning_of_day.to_i
+    count = 0
+
+    if Rails.cache.fetch('registrations:today_date') { today_date } == today_date
+      count = Rails.cache.fetch('registrations:today_increase_user_count') { today_increase_user_count_value }
+    else
+      count = today_increase_user_count_value
+      Rails.cache.write('registrations:today_date', today_date)
+      Rails.cache.write('registrations:today_increase_user_count', count)
+    end
+
+    count
+  end
+
+  def today_increase_user_count_value
+    User.confirmed.enabled.where('users.created_at >= ?', Time.now.utc.beginning_of_day).joins(:account).merge(Account.without_suspended).count
+  end
+
+  def registrations_in_time?
+    start_hour = Setting.registrations_start_hour || 0
+    end_hour = Setting.registrations_end_hour || 24
+    secondary_start_hour = Setting.registrations_secondary_start_hour || 0
+    secondary_end_hour = Setting.registrations_secondary_end_hour || 0
+
+    return true if start_hour >= end_hour && secondary_start_hour >= secondary_end_hour
+
+    current_hour = Time.now.utc.hour
+    primary_permitted = false
+    primary_permitted = start_hour <= current_hour && current_hour < end_hour if start_hour < end_hour && end_hour.positive?
+    secondary_permitted = false
+    secondary_permitted = secondary_start_hour <= current_hour && current_hour < secondary_end_hour if secondary_start_hour < secondary_end_hour && secondary_end_hour.positive?
+
+    primary_permitted || secondary_permitted
+  end
+
+  def reset_registration_limit_caches!
+    Rails.cache.delete('registrations:user_count')
+    Rails.cache.delete('registrations:today_increase_user_count')
+  end
+end