public Node(Move move, Node parent, State state, Deck deck)
{
this.state = state;
this.generatingMove = move;
this.parent = parent;
this.results = 0;
this.visits = 0;
this.children = new List<Node>();
this.untriedMoves = state.GetMoves(deck);
}
private State ApplyUp()
{
for (int j = GameEngine.ROWS - 2; j >= 0; j--)
{
for (int i = 0; i < GameEngine.COLUMNS; i++)
{
if (grid[i][j] != 0)
{
if (grid[i][j + 1] == 0)
{ // next cell is empty, just move the tile
MoveTile(i, j, i, j + 1);
this.columnsOrRowsWithMovedTiles.Add(i);
}
else if ((grid[i][j] == 1 && grid[i][j + 1] == 2)
|| (grid[i][j] == 2 && grid[i][j + 1] == 1)
|| (grid[i][j] > 2 && grid[i][j] == grid[i][j + 1]))
{ // tiles are mergeable
MergeTiles(i, j, i, j + 1);
this.columnsOrRowsWithMovedTiles.Add(i);
}
}
}
}
this.generatingMove = new PlayerMove(DIRECTION.UP);
return this;
}
private State ApplyRight()
{
for (int i = GameEngine.COLUMNS - 2; i >= 0; i--)
{
for (int j = 0; j < GameEngine.ROWS; j++)
{
if (grid[i][j] != 0)
{
if (grid[i + 1][j] == 0)
{ // next cell is empty, just move the tile
MoveTile(i, j, i + 1, j);
this.columnsOrRowsWithMovedTiles.Add(j);
}
else if ((grid[i][j] == 1 && grid[i + 1][j] == 2)
|| (grid[i][j] == 2 && grid[i + 1][j] == 1)
|| (grid[i][j] > 2 && grid[i][j] == grid[i + 1][j]))
{ // tiles are mergeable
MergeTiles(i, j, i + 1, j);
this.columnsOrRowsWithMovedTiles.Add(j);
}
}
}
}
this.generatingMove = new PlayerMove(DIRECTION.RIGHT);
return this;
}
// Applies the move and returns the result state
internal State ApplyMove(Move move)
{
if (move is PlayerMove)
{
State result = new State(BoardHelper.CloneGrid(this.grid), GameEngine.COMPUTER);
if (((PlayerMove)move).Direction == DIRECTION.LEFT)
{
return result.ApplyLeft();
}
else if (((PlayerMove)move).Direction == DIRECTION.RIGHT)
{
return result.ApplyRight();
}
else if (((PlayerMove)move).Direction == DIRECTION.UP)
{
return result.ApplyUp();
}
else if (((PlayerMove)move).Direction == DIRECTION.DOWN)
{
return result.ApplyDown();
}
return result;
}
else if (move is ComputerMove)
{
State result = new State(BoardHelper.CloneGrid(this.grid), GameEngine.PLAYER);
result.grid[((ComputerMove)move).Position.Item1][((ComputerMove)move).Position.Item2] = ((ComputerMove)move).Card;
result.generatingMove = (ComputerMove)move;
return result;
}
else
{
throw new Exception();
}
}
// adds a child node to the list of children
// after exploring a move - removes the move from untried
public Node AddChild(Move move, State state, Deck deck)
{
Node child = new Node(move, this, state, deck);
this.untriedMoves.Remove(move);
this.children.Add(child);
return child;
}