# frozen_string_literal: true

module Groupments
  class GroupShipments

    def self.call(shipments:)
      new(shipments: shipments).call.grouped_shipments
    end

    attr_reader :grouped_shipments

    def initialize(shipments:)
      @shipments = shipments
    end

    def call
      group_shipments

      self
    end

    private

    attr_reader :shipments

    def group_shipments
      @grouped_shipments = (non_groupable_shipments +
                            grouped_courier_shipments +
                            grouped_parcel_shipments
                           ).compact
    end

    def non_groupable_shipments
      shipments - courier_shipments - groupable_parcel_shipments
    end

    def grouped_courier_shipments
      [courier_shipment]
    end

    def grouped_parcel_shipments
      [parcel_shipment_without_hard_goods]
    end

    def parcel_shipment_without_hard_goods
      build_shipment_items_for(groupable_parcel_shipments)
    end

    def courier_shipment
      build_shipment_items_for(courier_shipments)
    end

    def courier_shipments
      @_courier_shipments ||= shipments.select(&:courier?)
    end

    def groupable_parcel_shipments
      @_groupable_parcel_shipments ||= shipments.select do |shipment|
        shipment.parcel? && !shipment.hard_goods?
      end
    end

    def build_shipment_items_for(shipments)
      return if shipments.empty?

      shipments.first.tap do |shipment|
        shipment.shipment_items = shipments.flat_map(&:shipment_items)
      end
    end
  end
end