using System;
using System.Threading;
using HeuristicLab.Algorithms.IteratedSymbolicExpressionConstruction;
using HeuristicLab.Problems.GeneticProgramming.ArtificialAnt;
using Microsoft.VisualStudio.TestTools.UnitTesting;

namespace Tests {
  [TestClass]
  public class IteratedSymbolicExpressionConstructionTest {
    [TestMethod]
    public void TestArtificialAnt() {

      // see Langdon and Poli, "Why Ants are Hard", Table 2 (http://marvin.cs.uidaho.edu/Teaching/CS472/santaFeTrailSpace.pdf)
      TestAlg(problem: new Problem(), policy: new RandomSymbolicExpressionConstructionPolicy(), maxLen: 3, expectedEvals: 3, expectedBestQuality: 3);
      TestAlg(problem: new Problem(), policy: new RandomSymbolicExpressionConstructionPolicy(), maxLen: 4, expectedEvals: 3, expectedBestQuality: 3);
      TestAlg(problem: new Problem(), policy: new RandomSymbolicExpressionConstructionPolicy(), maxLen: 5, expectedEvals: 21, expectedBestQuality: 11);
      TestAlg(problem: new Problem(), policy: new RandomSymbolicExpressionConstructionPolicy(), maxLen: 6, expectedEvals: 48, expectedBestQuality: 11);
      TestAlg(problem: new Problem(), policy: new RandomSymbolicExpressionConstructionPolicy(), maxLen: 10, expectedEvals: 25455, expectedBestQuality: 47);
      TestAlg(problem: new Problem(), policy: new RandomSymbolicExpressionConstructionPolicy(), maxLen: 13, expectedEvals: 3191259, expectedBestQuality: 89);

      // log of runtimes (28.08.2015), single core, Intel Core i5 @3.2 GHz
      // hh:mm:ss.ms
      // 00:00:00.037
      // 00:00:00.001
      // 00:00:00.003
      // 00:00:00.008
      // 00:00:05.499
      // 00:13:17.395
    }

    [TestMethod]
    public void TestStateAggregation() {
      var stateValueFunction = new TabularMaxStateValueFunction();
      stateValueFunction.StateFunction = new ParentChildStateFunction();
      var pol = new UcbSymbolicExpressionConstructionPolicy();
      pol.StateValueFunction = stateValueFunction;
      TestAlg(new Problem(), pol, maxLen: 13, expectedEvals: 3191259, expectedBestQuality: 89);
    }

    [TestMethod]
    public void TestStateValueApproximation() {
      var stateValueFunction = new GbtApproximateStateValueFunction();
      var pol = new EpsGreedySymbolicExpressionConstructionPolicy();
      pol.StateValueFunction = stateValueFunction;      
      TestAlg(new Problem(), pol, maxLen: 13, expectedEvals: 3191259, expectedBestQuality: 89);
    }

    private void TestAlg(Problem problem, ISymbolicExpressionConstructionPolicy policy, int maxLen, int expectedEvals, double expectedBestQuality) {
      var alg = new IteratedSymbolicExpressionConstruction();
      problem.Encoding.TreeLength = maxLen;
      alg.Problem = problem;
      alg.PolicyParameter.Value = policy;
      alg.MaximumEvaluations = 5000000;

      var wh = new ManualResetEvent(false);

      alg.Stopped += (sender, args) => { wh.Set(); };
      alg.ExceptionOccurred += (sender, args) => {
        wh.Set();
      };

      alg.Start();
      wh.WaitOne();

      Assert.AreEqual(expectedEvals, alg.ResultsEvaluations);
      Assert.AreEqual(expectedBestQuality, alg.ResultsBestQuality);

      Console.WriteLine(alg.ExecutionTime);
    }
  }
}