namespace HeuristicLab.Tests.Simplifier {
  using System;
  using HeuristicLab.Problems.ProgramSynthesis.Push.Expressions;
  using HeuristicLab.Problems.ProgramSynthesis.Push.Interpreter;
  using HeuristicLab.Problems.ProgramSynthesis.Push.Parser;
  using HeuristicLab.Problems.ProgramSynthesis.Push.Simplifier;
  using HeuristicLab.Random;

  using Microsoft.VisualStudio.TestTools.UnitTesting;

  [TestClass]
  public class SimplifierTests {

    [TestMethod]
    [TestProperty("Time", "Short")]
    [TestCategory("Simplifier")]
    public void SimplifySubProgramsTest() {
      var program = PushParser.ParseProgram("( ( ( ( ( 1 ) ) ) ) )");
      var result = PushParser.ParseProgram("( 1 )");
      var simplerProgram = Simplifier.SimplifySubPrograms(program);

      Console.WriteLine(simplerProgram);
      Assert.AreEqual(result, simplerProgram);
    }

    [TestMethod]
    [TestProperty("Time", "Short")]
    [TestCategory("Simplifier")]
    public void RemoveUnnecessaryExpressionsTest() {
      var program = PushParser.ParseProgram("( 5 ( INTEGER.DUP FLOAT.+ FLOAT.- ) ( EXEC.DO ( EXEC.IF ) EXEC.Y ) INTEGER.+ )");
      var result = PushParser.ParseProgram("( 5 INTEGER.DUP INTEGER.+ )");
      var pool = new PushInterpreterPool();
      var random = new MersenneTwister(1337);

      Func<PushProgram, double> evaluator = p => {
        using (var interpreter = pool.Create(random)) {
          interpreter.Run(p);
          return interpreter.IntegerStack.IsEmpty
            ? double.MaxValue
            : Math.Abs(interpreter.IntegerStack.Top - 10);
        }
      };

      var simplerProgram = Simplifier.Simplify(program, pool.PushConfiguration, evaluator);

      Console.WriteLine(simplerProgram);
      Assert.AreEqual(result, simplerProgram);
    }
  }
}