public static Board.State[,] Play(Board.State[,] Last)
{
Board.State[,] ReturnState;
List <Node> FoundNode = Node.Neighbourhood[GetLevel(Last)];
List <Node> Plays = new List <Node>();
int rot = 0;
int mir = 0;
foreach (Node Play in FoundNode)
{
if (Play.BoardsEqual(Last, out rot, out mir))
{
Plays = new List <Node>(Play.Children);
break;
}
}
Node Selected = new Node();
FoundNode = new List <Node>(Plays);
DiscardLosing();
GetWin();
if (Selected.Win != Board.State.P2)
{
Selected = FindTrap();
}
if (!Plays.Contains(Selected))
{
if (Plays.Count != 0)
{
Selected = Plays.OrderBy(o => o.Value).Last();
Console.WriteLine("Picking Last, " + Selected.Value);
}
else
{
Selected = FoundNode.Last();
}
}
//Restore to our original orientation and mirror
Selected.Rotate(rot);
Selected.Unmirror(mir);
ReturnState = Selected.Board;
return(ReturnState);
//--------------------------------
//AI actions
//Finds if one of the possible plays leads to a perfect win. Play is the AI play, SubPlay is the Player Play. If a play has all player plays lead to AI win, we can return that.
Node FindTrap()
{
//we should expand this to find more traps hidden in our tree
foreach (Node Play in Plays)
{
foreach (Node SubPlay in Play.Children)
{
bool Trap = true;
foreach (Node OurPlay in SubPlay.Children)
{
if (SubPlay.Win != Board.State.P2)
{
Trap = false;
break;
}
}
if (Trap)
{
return(Play);
}
}
}
return(new Node());
}
void DiscardLosing()
{
List <Node> Remove = new List <Node>();
foreach (Node a in Plays)
{
foreach (Node q in a.Children)
{
if (q.Win == Board.State.P1)
{
Remove.Add(a);
}
}
}
Plays = Plays.Except(Remove).ToList();
}
void GetWin()
{
Node q = Plays.Find(o => o.Win == Board.State.P2);
if (q != null)
{
Selected = q;
}
}
}