# 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) {
      # standard:disable Layout/ExtraSpacing
      [
        ["=", [0, "abc"], [0, "abc"]],
        ["!", [1, "def"], [1, "dxf"]],
        ["-", [2, "yyy"], [2,  nil]],
        ["=", [3, "xxx"], [2, "xxx"]],
        ["=", [4, "ghi"], [3, "ghi"]],
        ["=", [5, "jkl"], [4, "jkl"]]
      ]
      # standard:enable Layout/ExtraSpacing
    }

    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