module TimeBoss
  class Calendar
    module Support
      class TestMonthBasedChunk < MonthlyUnit
        NUM_MONTHS = 2

        def name
          "#{year_index}C#{index}"
        end
      end

      describe MonthlyUnit do
        let(:described_class) { TestMonthBasedChunk }
        let(:calendar) { double }
        let(:start_date) { Date.parse("2018-06-25") }
        let(:end_date) { Date.parse("2018-08-26") }
        let(:subject) { described_class.new(calendar, 2018, 4, start_date, end_date) }

        it "knows its stuff" do
          expect(subject.start_date).to eq start_date
          expect(subject.end_date).to eq end_date
          expect(subject.to_range).to eq start_date..end_date
        end

        it "can stringify itself" do
          expect(subject.to_s).to eq "2018C4: 2018-06-25 thru 2018-08-26"
        end

        describe "#weeks" do
          let(:base) { double(start_date: Date.parse("2018-01-01"), end_date: Date.parse("2018-12-30")) }
          before(:each) { allow(calendar).to receive(:year).with(2018).and_return base }

          it "can get the relevant weeks for the period" do
            allow(calendar).to receive(:supports_weeks?).and_return true
            result = subject.weeks
            result.each { |w| expect(w).to be_instance_of TimeBoss::Calendar::Week }
            expect(result.map { |w| w.start_date.to_s }).to eq [
              "2018-06-25",
              "2018-07-02",
              "2018-07-09",
              "2018-07-16",
              "2018-07-23",
              "2018-07-30",
              "2018-08-06",
              "2018-08-13",
              "2018-08-20"
            ]
          end

          it "blows up when weeks are not supported" do
            allow(calendar).to receive(:supports_weeks?).and_return false
            expect { subject.weeks }.to raise_error TimeBoss::Calendar::Support::Unit::UnsupportedUnitError
          end
        end

        context "navigation" do
          let(:result) { double }

          describe "#previous" do
            it "moves easily within itself" do
              expect(calendar).to receive(:test_month_based_chunk).with(48, 3).and_return result
              expect(described_class.new(calendar, 48, 4, nil, nil).previous).to eq result
            end

            it "flips to the previous container" do
              expect(calendar).to receive(:test_month_based_chunk).with(47, 6).and_return result
              expect(described_class.new(calendar, 48, 1, nil, nil).previous).to eq result
            end
          end

          describe "#next" do
            it "moves easily within itself" do
              expect(calendar).to receive(:test_month_based_chunk).with(48, 3).and_return result
              expect(described_class.new(calendar, 48, 2, nil, nil).next).to eq result
            end

            it "flips to the previous container" do
              expect(calendar).to receive(:test_month_based_chunk).with(48, 1).and_return result
              expect(described_class.new(calendar, 47, 6, nil, nil).next).to eq result
            end
          end
        end
      end
    end
  end
end