# frozen_string_literal: true

require 'spec_helper'

describe 'Diff::LCS.traverse_balanced' do
  include Diff::LCS::SpecHelper::Matchers

  shared_examples 'with a #change callback' do |s1, s2, result|
    it 'traverses s1 -> s2 correctly' do
      traversal = balanced_traversal(s1, s2, :balanced_callback)
      expect(traversal.result).to eq(result)
    end

    it 'traverses s2 -> s1 correctly' do
      traversal = balanced_traversal(s2, s1, :balanced_callback)
      expect(traversal.result).to eq(balanced_reverse(result))
    end
  end

  shared_examples 'without a #change callback' do |s1, s2, result|
    it 'traverses s1 -> s2 correctly' do
      traversal = balanced_traversal(s1, s2, :balanced_callback_no_change)
      expect(traversal.result).to eq(map_to_no_change(result))
    end

    it 'traverses s2 -> s1 correctly' do
      traversal = balanced_traversal(s2, s1, :balanced_callback_no_change)
      expect(traversal.result).to eq(map_to_no_change(balanced_reverse(result)))
    end
  end

  describe "identical string sequences ('abc')" do
    s1 = s2 = 'abc'

    result = [
      ['=', 0, 0],
      ['=', 1, 1],
      ['=', 2, 2]
    ]

    it_has_behavior 'with a #change callback', s1, s2, result
    it_has_behavior 'without a #change callback', s1, s2, result
  end

  describe 'identical array sequences %w(a b c)' do
    s1 = s2 = %w(a b c)

    result = [
      ['=', 0, 0],
      ['=', 1, 1],
      ['=', 2, 2]
    ]

    it_has_behavior 'with a #change callback', s1, s2, result
    it_has_behavior 'without a #change callback', s1, s2, result
  end

  describe 'sequences %w(a b c) & %w(a x c)' do
    s1 = %w(a b c)
    s2 = %w(a x c)

    result = [
      ['=', 0, 0],
      ['!', 1, 1],
      ['=', 2, 2]
    ]

    it_has_behavior 'with a #change callback', s1, s2, result
    it_has_behavior 'without a #change callback', s1, s2, result
  end

  describe 'sequences %w(a x y c) & %w(a v w c)' do
    s1 = %w(a x y c)
    s2 = %w(a v w c)

    result = [
      ['=', 0, 0],
      ['!', 1, 1],
      ['!', 2, 2],
      ['=', 3, 3]
    ]

    it_has_behavior 'with a #change callback', s1, s2, result
    it_has_behavior 'without a #change callback', s1, s2, result
  end

  describe 'sequences %w(x y c) & %w(v w c)' do
    s1 = %w(x y c)
    s2 = %w(v w c)
    result = [
      ['!', 0, 0],
      ['!', 1, 1],
      ['=', 2, 2]
    ]

    it_has_behavior 'with a #change callback', s1, s2, result
    it_has_behavior 'without a #change callback', s1, s2, result
  end

  describe 'sequences %w(a x y z) & %w(b v w)' do
    s1 = %w(a x y z)
    s2 = %w(b v w)
    result = [
      ['!', 0, 0],
      ['!', 1, 1],
      ['!', 2, 2],
      ['<', 3, 3]
    ]

    it_has_behavior 'with a #change callback', s1, s2, result
    it_has_behavior 'without a #change callback', s1, s2, result
  end

  describe 'sequences %w(a z) & %w(a)' do
    s1 = %w(a z)
    s2 = %w(a)
    result = [
      ['=', 0, 0],
      ['<', 1, 1]
    ]

    it_has_behavior 'with a #change callback', s1, s2, result
    it_has_behavior 'without a #change callback', s1, s2, result
  end

  describe 'sequences %w(z a) & %w(a)' do
    s1 = %w(z a)
    s2 = %w(a)
    result = [
      ['<', 0, 0],
      ['=', 1, 0]
    ]

    it_has_behavior 'with a #change callback', s1, s2, result
    it_has_behavior 'without a #change callback', s1, s2, result
  end

  describe 'sequences %w(a b c) & %w(x y z)' do
    s1 = %w(a b c)
    s2 = %w(x y z)
    result = [
      ['!', 0, 0],
      ['!', 1, 1],
      ['!', 2, 2]
    ]

    it_has_behavior 'with a #change callback', s1, s2, result
    it_has_behavior 'without a #change callback', s1, s2, result
  end

  describe 'sequences %w(abcd efgh ijkl mnoopqrstuvwxyz) & []' do
    s1 = %w(abcd efgh ijkl mnopqrstuvwxyz)
    s2 = []
    result = [
      ['<', 0, 0],
      ['<', 1, 0],
      ['<', 2, 0],
      ['<', 3, 0]
    ]

    it_has_behavior 'with a #change callback', s1, s2, result
    it_has_behavior 'without a #change callback', s1, s2, result
  end

  describe 'strings %q(a b c) & %q(a x c)' do
    s1 = 'a b c'
    s2 = 'a x c'

    result = [
      ['=', 0, 0],
      ['=', 1, 1],
      ['!', 2, 2],
      ['=', 3, 3],
      ['=', 4, 4]
    ]

    it_has_behavior 'with a #change callback', s1, s2, result
    it_has_behavior 'without a #change callback', s1, s2, result
  end

  describe 'strings %q(a x y c) & %q(a v w c)' do
    s1 = 'a x y c'
    s2 = 'a v w c'

    result = [
      ['=', 0, 0],
      ['=', 1, 1],
      ['!', 2, 2],
      ['=', 3, 3],
      ['!', 4, 4],
      ['=', 5, 5],
      ['=', 6, 6]
    ]

    it_has_behavior 'with a #change callback', s1, s2, result
    it_has_behavior 'without a #change callback', s1, s2, result
  end

  describe 'strings %q(x y c) & %q(v w c)' do
    s1 = 'x y c'
    s2 = 'v w c'
    result = [
      ['!', 0, 0],
      ['=', 1, 1],
      ['!', 2, 2],
      ['=', 3, 3],
      ['=', 4, 4]
    ]

    it_has_behavior 'with a #change callback', s1, s2, result
    it_has_behavior 'without a #change callback', s1, s2, result
  end

  describe 'strings %q(a x y z) & %q(b v w)' do
    s1 = 'a x y z'
    s2 = 'b v w'
    result = [
      ['!', 0, 0],
      ['=', 1, 1],
      ['!', 2, 2],
      ['=', 3, 3],
      ['!', 4, 4],
      ['<', 5, 5],
      ['<', 6, 5]
    ]

    it_has_behavior 'with a #change callback', s1, s2, result
    it_has_behavior 'without a #change callback', s1, s2, result
  end

  describe 'strings %q(a z) & %q(a)' do
    s1 = 'a z'
    s2 = 'a'
    result = [
      ['=', 0, 0],
      ['<', 1, 1],
      ['<', 2, 1]
    ]

    it_has_behavior 'with a #change callback', s1, s2, result
    it_has_behavior 'without a #change callback', s1, s2, result
  end

  describe 'strings %q(z a) & %q(a)' do
    s1 = 'z a'
    s2 = 'a'
    result = [
      ['<', 0, 0],
      ['<', 1, 0],
      ['=', 2, 0]
    ]

    it_has_behavior 'with a #change callback', s1, s2, result
    it_has_behavior 'without a #change callback', s1, s2, result
  end

  describe 'strings %q(a b c) & %q(x y z)' do
    s1 = 'a b c'
    s2 = 'x y z'
    result = [
      ['!', 0, 0],
      ['=', 1, 1],
      ['!', 2, 2],
      ['=', 3, 3],
      ['!', 4, 4]
    ]

    it_has_behavior 'with a #change callback', s1, s2, result
    it_has_behavior 'without a #change callback', s1, s2, result
  end

  describe 'strings %q(abcd efgh ijkl mnopqrstuvwxyz) & %q()' do
    s1 = 'abcd efgh ijkl mnopqrstuvwxyz'
    s2 = ''
    result = [
      ['<',  0, 0],
      ['<',  1, 0],
      ['<',  2, 0],
      ['<',  3, 0],
      ['<',  4, 0],
      ['<',  5, 0],
      ['<',  6, 0],
      ['<',  7, 0],
      ['<',  8, 0],
      ['<',  9, 0],
      ['<', 10, 0],
      ['<', 11, 0],
      ['<', 12, 0],
      ['<', 13, 0],
      ['<', 14, 0],
      ['<', 15, 0],
      ['<', 16, 0],
      ['<', 17, 0],
      ['<', 18, 0],
      ['<', 19, 0],
      ['<', 20, 0],
      ['<', 21, 0],
      ['<', 22, 0],
      ['<', 23, 0],
      ['<', 24, 0],
      ['<', 25, 0],
      ['<', 26, 0],
      ['<', 27, 0],
      ['<', 28, 0]
    ]

    it_has_behavior 'with a #change callback', s1, s2, result
    it_has_behavior 'without a #change callback', s1, s2, result
  end
end