# frozen_string_literal: true

require 'spec_helper'

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

  shared_examples 'compare sequences correctly' do
    it 'compares s1 -> s2 correctly' do
      expect(Diff::LCS.sdiff(s1, s2)).to eq(context_diff(result))
    end

    it 'compares s2 -> s1 correctly' do
      expect(Diff::LCS.sdiff(s2, s1)).to eq(context_diff(reverse_sdiff(result)))
    end
  end

  describe 'using seq1 & seq2' do
    let(:s1) { seq1 }
    let(:s2) { seq2 }
    let(:result) { correct_forward_sdiff }

    it_has_behavior 'compare sequences correctly'
  end

  describe 'using %w(abc def yyy xxx ghi jkl) & %w(abc dxf xxx ghi jkl)' do
    let(:s1) { %w(abc def yyy xxx ghi jkl) }
    let(:s2) { %w(abc dxf xxx ghi jkl) }
    let(:result) {
      [
        ['=', [0, 'abc'], [0, 'abc']],
        ['!', [1, 'def'], [1, 'dxf']],
        ['-', [2, 'yyy'], [2,  nil]],
        ['=', [3, 'xxx'], [2, 'xxx']],
        ['=', [4, 'ghi'], [3, 'ghi']],
        ['=', [5, 'jkl'], [4, 'jkl']]
      ]
    }

    it_has_behavior 'compare sequences correctly'
  end

  describe 'using %w(a b c d e) & %w(a e)' do
    let(:s1) { %w(a b c d e) }
    let(:s2) { %w(a e) }
    let(:result) {
      [
        ['=', [0, 'a'], [0, 'a']],
        ['-', [1, 'b'], [1, nil]],
        ['-', [2, 'c'], [1, nil]],
        ['-', [3, 'd'], [1, nil]],
        ['=', [4, 'e'], [1, 'e']]
      ]
    }

    it_has_behavior 'compare sequences correctly'
  end

  describe 'using %w(a e) & %w(a b c d e)' do
    let(:s1) { %w(a e) }
    let(:s2) { %w(a b c d e) }
    let(:result) {
      [
        ['=', [0, 'a'], [0, 'a']],
        ['+', [1, nil], [1, 'b']],
        ['+', [1, nil], [2, 'c']],
        ['+', [1, nil], [3, 'd']],
        ['=', [1, 'e'], [4, 'e']]
      ]
    }

    it_has_behavior 'compare sequences correctly'
  end

  describe 'using %w(v x a e) & %w(w y a b c d e)' do
    let(:s1) { %w(v x a e) }
    let(:s2) { %w(w y a b c d e) }
    let(:result) {
      [
        ['!', [0, 'v'], [0, 'w']],
        ['!', [1, 'x'], [1, 'y']],
        ['=', [2, 'a'], [2, 'a']],
        ['+', [3, nil], [3, 'b']],
        ['+', [3, nil], [4, 'c']],
        ['+', [3, nil], [5, 'd']],
        ['=', [3, 'e'], [6, 'e']]
      ]
    }

    it_has_behavior 'compare sequences correctly'
  end

  describe 'using %w(x a e) & %w(a b c d e)' do
    let(:s1) { %w(x a e) }
    let(:s2) { %w(a b c d e) }
    let(:result) {
      [
        ['-', [0, 'x'], [0, nil]],
        ['=', [1, 'a'], [0, 'a']],
        ['+', [2, nil], [1, 'b']],
        ['+', [2, nil], [2, 'c']],
        ['+', [2, nil], [3, 'd']],
        ['=', [2, 'e'], [4, 'e']]
      ]
    }

    it_has_behavior 'compare sequences correctly'
  end

  describe 'using %w(a e) & %w(x a b c d e)' do
    let(:s1) { %w(a e) }
    let(:s2) { %w(x a b c d e) }
    let(:result) {
      [
        ['+', [0, nil], [0, 'x']],
        ['=', [0, 'a'], [1, 'a']],
        ['+', [1, nil], [2, 'b']],
        ['+', [1, nil], [3, 'c']],
        ['+', [1, nil], [4, 'd']],
        ['=', [1, 'e'], [5, 'e']]
      ]
    }

    it_has_behavior 'compare sequences correctly'
  end

  describe 'using %w(a e v) & %w(x a b c d e w x)' do
    let(:s1) { %w(a e v) }
    let(:s2) { %w(x a b c d e w x) }
    let(:result) {
      [
        ['+', [0, nil], [0, 'x']],
        ['=', [0, 'a'], [1, 'a']],
        ['+', [1, nil], [2, 'b']],
        ['+', [1, nil], [3, 'c']],
        ['+', [1, nil], [4, 'd']],
        ['=', [1, 'e'], [5, 'e']],
        ['!', [2, 'v'], [6, 'w']],
        ['+', [3, nil], [7, 'x']]
      ]
    }

    it_has_behavior 'compare sequences correctly'
  end

  describe 'using %w() & %w(a b c)' do
    let(:s1) { %w() }
    let(:s2) { %w(a b c) }
    let(:result) {
      [
        ['+', [0, nil], [0, 'a']],
        ['+', [0, nil], [1, 'b']],
        ['+', [0, nil], [2, 'c']]
      ]
    }

    it_has_behavior 'compare sequences correctly'
  end

  describe 'using %w(a b c) & %w(1)' do
    let(:s1) { %w(a b c) }
    let(:s2) { %w(1) }
    let(:result) {
      [
        ['!', [0, 'a'], [0, '1']],
        ['-', [1, 'b'], [1, nil]],
        ['-', [2, 'c'], [1, nil]]
      ]
    }

    it_has_behavior 'compare sequences correctly'
  end

  describe 'using %w(a b c) & %w(c)' do
    let(:s1) { %w(a b c) }
    let(:s2) { %w(c) }
    let(:result) {
      [
        ['-', [0, 'a'], [0, nil]],
        ['-', [1, 'b'], [0, nil]],
        ['=', [2, 'c'], [0, 'c']]
      ]
    }

    it_has_behavior 'compare sequences correctly'
  end

  describe 'using %w(abcd efgh ijkl mnop) & []' do
    let(:s1) { %w(abcd efgh ijkl mnop) }
    let(:s2) { [] }
    let(:result) {
      [
        ['-', [0, 'abcd'], [0, nil]],
        ['-', [1, 'efgh'], [0, nil]],
        ['-', [2, 'ijkl'], [0, nil]],
        ['-', [3, 'mnop'], [0, nil]]
      ]
    }

    it_has_behavior 'compare sequences correctly'
  end

  describe 'using [[1,2]] & []' do
    let(:s1) { [[1, 2]] }
    let(:s2) { [] }
    let(:result) {
      [
        ['-', [0, [1, 2]], [0, nil]]
      ]
    }

    it_has_behavior 'compare sequences correctly'
  end
end