# Copyright (C) 2024 Manuel Bustillo

require 'rails_helper'

module Tables
  RSpec.describe Shift do
    describe '#each' do
      let(:shifts) do
        acc = []
        described_class.new(initial_solution).each do |solution|
          acc << solution.tables.map(&:dup)
        end
        acc
      end

      context 'when there are two tables with two people each' do
        let(:initial_solution) do
          Distribution.new(min_per_table: 2, max_per_table: 2).tap do |distribution|
            distribution.tables << Set[:a, :b].to_table
            distribution.tables << Set[:c, :d].to_table
          end
        end

        it 'yields all possible shifts between the tables' do
          expect(shifts).to contain_exactly(
            [Set[:b], Set[:c, :d, :a]],
            [Set[:a], Set[:c, :d, :b]],
            [Set[:b, :a, :d], Set[:c]],
            [Set[:b, :a, :c], Set[:d]]
          )
        end
      end

      context 'when there are two tables with three people each' do
        let(:initial_solution) do
          Distribution.new(min_per_table: 3, max_per_table: 3).tap do |distribution|
            distribution.tables << Set[:a, :b, :c].to_table
            distribution.tables << Set[:d, :e, :f].to_table
          end
        end

        it 'yields all possible shifts between the tables' do
          expect(shifts).to contain_exactly(
            [Set[:b, :c], Set[:d, :e, :f, :a]],
            [Set[:c, :a], Set[:d, :e, :f, :b]],
            [Set[:a, :b], Set[:d, :e, :f, :c]],
            [Set[:a, :b, :c, :d], Set[:e, :f]],
            [Set[:a, :b, :c, :e], Set[:d, :f]],
            [Set[:a, :b, :c, :f], Set[:d, :e]]
          )
        end
      end
    end
  end
end