#region License Information
/* HeuristicLab
 * Copyright (C) 2002-2013 Heuristic and Evolutionary Algorithms Laboratory (HEAL)
 *
 * This file is part of HeuristicLab.
 *
 * HeuristicLab is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * HeuristicLab is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with HeuristicLab. If not, see <http://www.gnu.org/licenses/>.
 */
#endregion

using System;
using System.Collections.Generic;
using System.Linq;
using Microsoft.VisualStudio.TestTools.UnitTesting;
using HeuristicLab.Grammars;
namespace Test {
  [TestClass]
  public class TestGrammar {
    [TestMethod]
    public void TestSimpleGrammar() {
      var gStr =
        @"S -> A
          A->a B
          B ->S b | S a|C b 
          C-> a  aa   aaa
         ";
      var g = HeuristicLab.Grammars.Grammar.FromString(gStr);
      Assert.AreEqual(g.StartSymbol, new Symbol("S"));
      Assert.AreEqual(g.TerminalSymbols.Count(), 4);
      Assert.AreEqual(g.NonTerminalSymbols.Count(), 4);
      Assert.IsTrue(g.TerminalSymbols.Contains(new Symbol("aaa")));
      Assert.IsTrue(g.TerminalSymbols.Contains(new Symbol("aa")));
      Assert.IsTrue(g.NonTerminalSymbols.Contains(new Symbol("S")));
      Assert.IsTrue(g.NonTerminalSymbols.Contains(new Symbol("B")));
      Assert.IsTrue(g.NonTerminalSymbols.Contains(new Symbol("C")));
      Assert.IsTrue(g.NonTerminalSymbols.Contains(new Symbol("A")));
    }


    [TestMethod]
    public void TestAttributedGrammar() {
      var gStr =
        @"S -> A
          A<int a0, out int a1>->a B<a0, a1>
          B<int a0, ref int a1> ->S b | S a|C<a0, a1> b 
          C<int a0, ref int a1> -> a  aa   aaa
         ";
      var g = HeuristicLab.Grammars.AttributedGrammar.FromString(gStr);
      Assert.AreEqual(g.StartSymbol, new Symbol("S"));
      Assert.AreEqual(g.TerminalSymbols.Count(), 4);
      Assert.AreEqual(g.NonTerminalSymbols.Count(), 4);
      Assert.IsTrue(g.TerminalSymbols.Contains(new Symbol("aaa")));
      Assert.IsTrue(g.TerminalSymbols.Contains(new Symbol("aa")));
      Assert.IsTrue(g.NonTerminalSymbols.Contains(new Symbol("S")));
      Assert.IsTrue(g.NonTerminalSymbols.Contains(new Symbol("B")));
      Assert.IsTrue(g.NonTerminalSymbols.Contains(new Symbol("A")));
      Assert.IsTrue(g.NonTerminalSymbols.Contains(new Symbol("C")));
    }


    [TestMethod]
    public void TestLanguage() {
      var gStr =
        @"S -> a B | b A
          A-> a | a S | b A A 
          B -> b | b S | a B B
         ";
      var g = HeuristicLab.Grammars.Grammar.FromString(gStr);
      var l = new Language(g);
      var s2 = new string[][]
        {
          new string[] {"a", "b"},
          new string[] {"b", "a"}
        };
      var s4 = new string[][]
        {
          new [] {"a", "a", "b", "b"},
          new [] {"a", "b", "a", "b"},
          new [] {"a", "b", "b", "a"},
          new [] {"b", "b", "a", "a"},
          new [] {"b", "a", "b", "a"},
          new [] {"b", "a", "a", "b"}
        };


      var l2 = l.Where(s => s.Count() == 2).Take(2);
      var l4 = l.Where(s => s.Count() == 4).Take(6);

      Assert.IsTrue(l2.Intersect(s2, new SequenceComparer()).Count() == l2.Count());
      Assert.IsTrue(l4.Intersect(s4, new SequenceComparer()).Count() == l4.Count());
    }
  }

  public class SequenceComparer : IEqualityComparer<IEnumerable<string>> {
    public bool Equals(IEnumerable<string> x, IEnumerable<string> y) {
      return x.Count() == y.Count() &&
        x.Zip(y, (s, t) => s == t).All(eq => eq);
    }

    public int GetHashCode(IEnumerable<string> obj) {
      if (!obj.Any()) return 0;
      else return obj.First().GetHashCode();
    }
  }
}