require_relative '../spec_helper'

describe DataMapper::Collection do
  supported_by :sqlite, :mysql, :postgres do
    let(:dragons)   { Dragon.all  }
    let(:countries) { Country.all }

    it_behaves_like 'It Has Setup Resources'
    it_behaves_like 'An Aggregatable Class'

    describe 'ignore invalid query' do
      let(:dragons) { Dragon.all.all(id: []) }

      %i(size count).each do |method|
        describe "##{method}" do
          subject { dragons.send(method) }

          it { is_expected.to eq 0 }
        end
      end

      describe '#min' do
        subject { dragons.min(:id) }

        it { is_expected.to be_nil }
      end

      describe '#max' do
        subject { dragons.max(:id) }

        it { is_expected.to be_nil }
      end

      describe '#avg' do
        subject { dragons.avg(:id) }

        it { is_expected.to be_nil }
      end

      describe '#sum' do
        subject { dragons.sum(:id) }

        it { is_expected.to be_nil }
      end

      describe '#aggregate' do
        subject { dragons.aggregate(:id) }

        it { is_expected.to eq [] }
      end
    end

    context 'with collections created with Set operations' do
      let(:collection) { dragons.all(name: 'George') | dragons.all(name: 'Puff') }

      describe '#size' do
        subject { collection.size }

        it { is_expected.to eq 2 }
      end

      describe '#count' do
        subject { collection.count }

        it { is_expected.to eq 2 }
      end

      describe '#min' do
        subject { collection.min(:toes_on_claw) }

        it { is_expected.to eq 3 }
      end

      describe '#max' do
        subject { collection.max(:toes_on_claw) }

        it { is_expected.to eq 4 }
      end

      describe '#avg' do
        subject { collection.avg(:toes_on_claw) }

        it { is_expected.to eq 3.5 }
      end

      describe '#sum' do
        subject { collection.sum(:toes_on_claw) }

        it { is_expected.to eq 7 }
      end

      describe '#aggregate' do
        subject { collection.aggregate(:all.count, :name.count, :toes_on_claw.min, :toes_on_claw.max, :toes_on_claw.avg, :toes_on_claw.sum) }

        it { is_expected.to eq [2, 2, 3, 4, 3.5, 7] }
      end
    end

    context 'with a collection limited to 1 result' do
      let(:dragons) { Dragon.all(limit: 1) }

      describe '#size' do
        subject { dragons.size }

        it { is_expected.to eq 1 }
      end

      describe '#count' do
        subject { dragons.count }

        it {
          pending 'TODO: make count apply to the limited collection. Currently limit applies after the count'
          is_expected.to eq 1
        }
      end
    end

    context 'with the order reversed by the grouping field' do
      subject { dragons.aggregate(:birth_at, :all.count) }

      let(:dragons) { Dragon.all(order: [:birth_at.desc]) }

      it 'displays the results in reverse order' do
        is_expected.to eq Dragon.aggregate(:birth_at, :all.count).reverse
      end
    end
  end
end