using Nemerle.Collections;

namespace NSokoban
{
    public module LocalSearch
    {
  public SimulatedAnnealing (map : SMap, p : double) : bool * option [SMap]
  {
      mutable queue = Queue();
      
      mutable ppb = p;
      
      mutable depth = 0;
      
      def r = System.Random ();

      queue.Enqueue (map);

      mutable next = map;

      def start = System.DateTime.Now;

      while(!next.GoalTest () && !(queue.Count == 0))
      {        
    def m = queue.Dequeue();        

    when(depth < m.moves_so_far.Length)
    {
        ++depth;
        System.Console.WriteLine(depth);
    }

    if( m.F < next.F)
    {
        next = m;
        List.Iter(m.NextStates(),fun(x){queue.Enqueue(x);});
    }
    else
        when(r.NextDouble () < ppb)
        {
      next = m;
      List.Iter(m.NextStates(true),fun(x){queue.Enqueue(x);});
      ppb -= 0.0001;
        }
      }

      if(next.GoalTest ())
      {
    System.Console.WriteLine("Found after "+(start - System.DateTime.Now).ToString ());  
    (true,Some (next));
      }
      else
    (false,None ())
  }
    }
}