Remove nested deactivation periods

app/helpers/locations_helper.rb

@@ -46,7 +46,7 @@ module LocationsHelper
   def active_periods(location)
     periods = [ActivePeriod.new(location.available_from, nil)]
 
-    sorted_deactivation_periods = location.location_deactivation_periods.sort_by(&:deactivation_date)
+    sorted_deactivation_periods = remove_nested_periods(location.location_deactivation_periods.sort_by(&:deactivation_date))
     sorted_deactivation_periods.each do |deactivation|
       periods.find { |period| period.to.nil? }.to = deactivation.deactivation_date
       periods << ActivePeriod.new(deactivation.reactivation_date, nil)
@@ -71,4 +71,14 @@ private
   def remove_overlapping_and_empty_periods(periods)
     periods.select { |period| ((period.to.nil? && period.from.present?) || (period.from.present? && period.from < period.to)) }
   end
+
+  def remove_nested_periods(periods)
+    periods.select { |inner_period| periods.none? { |outer_period| is_nested?(inner_period, outer_period) } }
+  end
+
+  def is_nested?(inner, outer)
+    return false if inner == outer || [inner.deactivation_date, inner.reactivation_date, outer.deactivation_date, outer.reactivation_date].any?(&:blank?)
+
+    [inner.deactivation_date, inner.reactivation_date].all? { |date| date.between?(outer.deactivation_date, outer.reactivation_date) }
+  end
 end

spec/helpers/locations_helper_spec.rb

@@ -58,7 +58,6 @@ RSpec.describe LocationsHelper do
       Timecop.unfreeze
     end
 
-    context "when there have not been any previous deactivations" do
     it "returns one active period without to date" do
       expect(active_periods(location).count).to eq(1)
       expect(active_periods(location).first).to have_attributes(from: Time.zone.local(2022, 4, 1), to: nil)
@@ -121,6 +120,14 @@ RSpec.describe LocationsHelper do
       expect(active_periods(location).first).to have_attributes(from: Time.zone.local(2022, 4, 1), to: Time.zone.local(2022, 4, 6))
       expect(active_periods(location).second).to have_attributes(from: Time.zone.local(2022, 11, 11), to: nil)
     end
+
+    it "returns correct active periods when a full deactivation period happens during another deactivation period" do
+      location.location_deactivation_periods << FactoryBot.create(:location_deactivation_period, deactivation_date: Time.zone.local(2022, 5, 5), reactivation_date: Time.zone.local(2022, 6, 11))
+      location.location_deactivation_periods << FactoryBot.create(:location_deactivation_period, deactivation_date: Time.zone.local(2022, 4, 6), reactivation_date: Time.zone.local(2022, 7, 7))
+
+      expect(active_periods(location).count).to eq(2)
+      expect(active_periods(location).first).to have_attributes(from: Time.zone.local(2022, 4, 1), to: Time.zone.local(2022, 4, 6))
+      expect(active_periods(location).second).to have_attributes(from: Time.zone.local(2022, 7, 7), to: nil)
     end
   end