# Copyright (C) 2024 Manuel Bustillo

# frozen_string_literal: true

require 'rails_helper'

module Tables
  RSpec.describe Swap do
    describe '#each' do
      let(:swaps) do
        acc = []
        described_class.new(initial_solution).each do |solution| # rubocop:disable Style/MapIntoArray -- #map is not implemented
          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 swaps between the tables' do
          expect(swaps).to contain_exactly(
            [Set[:a, :d], Set[:c, :b]],
            [Set[:b, :c], Set[:d, :a]],
            [Set[:a, :c], Set[:d, :b]],
            [Set[:b, :d], Set[:c, :a]]
          )
        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 swaps between the tables' do
          expect(swaps).to contain_exactly(
            [Set[:b, :c, :d], Set[:e, :f, :a]],
            [Set[:b, :c, :e], Set[:f, :d, :a]],
            [Set[:b, :c, :f], Set[:d, :e, :a]],
            [Set[:c, :a, :d], Set[:e, :f, :b]],
            [Set[:c, :a, :e], Set[:f, :d, :b]],
            [Set[:c, :a, :f], Set[:d, :e, :b]],
            [Set[:a, :b, :d], Set[:e, :f, :c]],
            [Set[:a, :b, :e], Set[:f, :d, :c]],
            [Set[:a, :b, :f], Set[:d, :e, :c]]
          )
        end
      end

      context 'when there are three 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
            distribution.tables << Set[:e, :f].to_table
          end
        end

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