Add basic form object for enterprise fee summary

config/locales/en.yml

@@ -2681,6 +2681,11 @@ See the %{link} to find out more about %{sitename}'s features and to start using
     signup:
       start_free_profile: "Start with a free profile, and expand when you're ready!"
 
+  order_management:
+    reports:
+      enterprise_fee_summary:
+        date_end_before_start_error: "must be after start"
+
   spree:
     # TODO: remove `email` key once we get to Spree 2.0
     email: Email

lib/order_management/reports/enterprise_fee_summary/parameters.rb

@@ -0,0 +1,46 @@
+module OrderManagement
+  module Reports
+    module EnterpriseFeeSummary
+      class Parameters
+        @i18n_scope = "order_management.reports.enterprise_fee_summary"
+
+        DATE_END_BEFORE_START_ERROR = I18n.t("date_end_before_start_error", scope: @i18n_scope)
+
+        extend ActiveModel::Naming
+        include ActiveModel::Validations
+
+        attr_accessor :start_at, :end_at, :distributor_ids, :producer_ids, :order_cycle_ids,
+                      :enterprise_fee_ids, :shipping_method_ids, :payment_method_ids
+
+        validates :start_at, :end_at, date_time_string: true
+        validates :distributor_ids, :producer_ids, integer_array: true
+        validates :order_cycle_ids, integer_array: true
+        validates :enterprise_fee_ids, integer_array: true
+        validates :shipping_method_ids, :payment_method_ids, integer_array: true
+
+        validate :require_valid_datetime_range
+
+        def initialize(attributes = {})
+          self.distributor_ids = []
+          self.producer_ids = []
+          self.order_cycle_ids = []
+          self.enterprise_fee_ids = []
+          self.shipping_method_ids = []
+          self.payment_method_ids = []
+
+          attributes.each do |key, value|
+            public_send("#{key}=", value)
+          end
+        end
+
+        protected
+
+        def require_valid_datetime_range
+          return if start_at.blank? || end_at.blank?
+
+          errors.add(:end_at, DATE_END_BEFORE_START_ERROR) unless start_at < end_at
+        end
+      end
+    end
+  end
+end

spec/lib/order_management/reports/enterprise_fee_summary/parameters_spec.rb

@@ -0,0 +1,44 @@
+require "spec_helper"
+
+require "date_time_string_validator"
+require "order_management/reports/enterprise_fee_summary/parameters"
+
+describe OrderManagement::Reports::EnterpriseFeeSummary::Parameters do
+  describe "validation" do
+    let(:parameters) { described_class.new }
+
+    it "allows all parameters to be blank" do
+      expect(parameters).to be_valid
+    end
+
+    context "for type of parameters" do
+      it { expect(subject).to validate_date_time_format_of(:start_at) }
+      it { expect(subject).to validate_date_time_format_of(:end_at) }
+      it { expect(subject).to validate_integer_array(:distributor_ids) }
+      it { expect(subject).to validate_integer_array(:producer_ids) }
+      it { expect(subject).to validate_integer_array(:order_cycle_ids) }
+      it { expect(subject).to validate_integer_array(:enterprise_fee_ids) }
+      it { expect(subject).to validate_integer_array(:shipping_method_ids) }
+      it { expect(subject).to validate_integer_array(:payment_method_ids) }
+
+      describe "requiring start_at to be before end_at" do
+        let(:now) { Time.zone.now }
+
+        it "adds error when start_at is after end_at" do
+          allow(subject).to receive(:start_at) { now.to_s }
+          allow(subject).to receive(:end_at) { (now - 1.hour).to_s }
+
+          expect(subject).not_to be_valid
+          expect(subject.errors[:end_at]).to eq([described_class::DATE_END_BEFORE_START_ERROR])
+        end
+
+        it "does not add error when start_at is before end_at" do
+          allow(subject).to receive(:start_at) { now.to_s }
+          allow(subject).to receive(:end_at) { (now + 1.hour).to_s }
+
+          expect(subject).to be_valid
+        end
+      end
+    end
+  end
+end