/**
* Check if a node is in the main variation of the tree.
*
* @param node The node.
* @return <tt>true</tt>, if the given node is in the main variation, which is the sequence of
* nodes starting from the root of the tree and always following the first child.
*/
public static boolean isInMainVariation(ConstNode node) {
while (node.getFatherConst() != null) {
if (node.getFatherConst().getChildConst(0) != node) return false;
node = node.getFatherConst();
}
return true;
}
/**
* Get depth of a node.
*
* @param node The node.
* @return The number of nodes in the sequence from the root node to the given node, excluding the
* given node (which means that the root node has depth 0).
*/
public static int getDepth(ConstNode node) {
int depth = 0;
while (node.getFatherConst() != null) {
node = node.getFatherConst();
++depth;
}
return depth;
}
/** Return next variation before this node. */
public static ConstNode getNextEarlierVariation(ConstNode node) {
ConstNode child = node;
node = node.getFatherConst();
while (node != null && node.variationAfter(child) == null) {
child = node;
node = node.getFatherConst();
}
if (node == null) return null;
return node.variationAfter(child);
}
/** Return previous variation before this node. */
public static ConstNode getPreviousEarlierVariation(ConstNode node) {
ConstNode child = node;
node = node.getFatherConst();
while (node != null && node.variationBefore(child) == null) {
child = node;
node = node.getFatherConst();
}
if (node == null) return null;
node = node.variationBefore(child);
if (node == null) return null;
while (hasSubtree(node)) node = node.getChildConst(node.getNumberChildren() - 1);
return node;
}
/**
* Find first node with a certain move number in main variation of a given node.
*
* @param node The given node.
* @param moveNumber The move number of the wanted node.
* @return The node with the given move number or <code>null</code> if no such node exists.
*/
public static ConstNode findByMoveNumber(ConstNode node, int moveNumber) {
int maxMoveNumber = getMoveNumber(node) + getMovesLeft(node);
if (moveNumber < 0 || moveNumber > maxMoveNumber) return null;
if (moveNumber <= getMoveNumber(node)) {
while (node.getFatherConst() != null
&& (getMoveNumber(node) > moveNumber || node.getMove() == null))
node = node.getFatherConst();
} else {
while (node.getChildConst() != null && getMoveNumber(node) < moveNumber)
node = node.getChildConst();
}
return node;
}
/**
* Get nodes in path from a given node to the root node.
*
* @param node The node
* @param result The resulting path. Passed as an argument to allow reusing an array list. It will
* be cleared before it is used.
*/
public static void getPathToRoot(ConstNode node, ArrayList<ConstNode> result) {
result.clear();
while (node != null) {
result.add(node);
node = node.getFatherConst();
}
}
/**
* Get the move number of a node.
*
* @param node The node.
* @return The total number of moves in the sequence of nodes from the root node to the given
* node, including the given node.
*/
public static int getMoveNumber(ConstNode node) {
int moveNumber = 0;
while (node != null) {
if (node.getMove() != null) ++moveNumber;
node = node.getFatherConst();
}
return moveNumber;
}
/**
* Select a random node in the main variation within a certain depth interval.
*
* @param root The root node
* @param minDepth The minimum depth of the interval (inclusive)
* @param maxDepth The maximum depth of the interval (inclusive)
* @return A random node in the given depth interval, null, if there is none.
*/
public static ConstNode selectRandom(ConstNode root, int minDepth, int maxDepth) {
ConstNode last = getLast(root);
int depth = getDepth(last);
if (depth < minDepth) return null;
if (depth < maxDepth) maxDepth = depth;
int idx = minDepth + s_random.nextInt(maxDepth - minDepth + 1);
ConstNode node = last;
for (int i = depth; i != idx; --i) node = node.getFatherConst();
return node;
}
/**
* Check that the time left for a color at a node is known. Returns true, if the last node
* (including the given one) containing a move of the given color also contains information about
* the time left after the move for the color. If a previous node with a game info containing time
* settings exists and no move of the given color was played since then, the function also returns
* true.
*/
public static boolean isTimeLeftKnown(ConstNode node, GoColor color) {
while (node != null) {
Move move = node.getMove();
if (move != null && move.getColor() == color) return !Double.isNaN(node.getTimeLeft(color));
ConstGameInfo info = node.getGameInfoConst();
if (info != null && info.getTimeSettings() != null) return true;
node = node.getFatherConst();
}
return false;
}
/** Check if a node contains a move and has sibling nodes containing other moves. */
public static boolean hasSiblingMoves(ConstNode node) {
ConstNode father = node.getFatherConst();
if (father == null) return false;
Move move = node.getMove();
if (move == null) return false;
for (int i = 0; i < father.getNumberChildren(); ++i) {
Move childMove = father.getChildConst(i).getMove();
if (childMove != null && childMove != move) return true;
}
return false;
}
/**
* Check if game is in cleanup stage. Cleanup stage is after two consecutive pass moves have been
* played.
*/
public static boolean isInCleanup(ConstNode node) {
boolean lastPass = false;
while (node != null) {
Move move = node.getMove();
if (move != null) {
if (move.getPoint() == null) {
if (lastPass) return true;
lastPass = true;
} else lastPass = false;
}
node = node.getFatherConst();
}
return false;
}
/**
* Get a text representation of the variation to a certain node. The string contains the number of
* the child for each node with more than one child in the path from the root node to this node.
* The childs are counted starting with 1 and the numbers are separated by colons.
*/
public static String getVariationString(ConstNode node) {
ArrayList<String> list = new ArrayList<String>();
while (node != null) {
ConstNode father = node.getFatherConst();
if (father != null && father.getNumberChildren() > 1) {
int index = father.getChildIndex(node) + 1;
list.add(0, Integer.toString(index));
}
node = father;
}
StringBuilder result = new StringBuilder(list.size() * 3);
for (int i = 0; i < list.size(); ++i) {
result.append(list.get(i));
if (i < list.size() - 1) result.append('.');
}
return result.toString();
}
/** Find the last node that was still in the main variation. */
public static ConstNode getBackToMainVariation(ConstNode node) {
while (!isInMainVariation(node)) node = node.getFatherConst();
return node;
}
/**
* Get the root node.
*
* @param node The node.
* @return The root node of the tree that the given node belongs to.
*/
public static ConstNode getRoot(ConstNode node) {
while (node.getFatherConst() != null) node = node.getFatherConst();
return node;
}
/** Return next variation of this node. */
public static ConstNode getNextVariation(ConstNode node) {
ConstNode father = node.getFatherConst();
if (father == null) return null;
return father.variationAfter(node);
}
/** Return previous variation of this node. */
public static ConstNode getPreviousVariation(ConstNode node) {
ConstNode father = node.getFatherConst();
if (father == null) return null;
return father.variationBefore(node);
}
/**
* Get node reached by going a number of nodes backward.
*
* @param node The start node.
* @param n The number of moves to go backward.
* @return The node reached by going n moves backward or the root node of the tree, if there are
* less than n nodes in the sequence before the start node.
*/
public static ConstNode backward(ConstNode node, int n) {
assert n >= 0;
for (int i = 0; i < n && node.getFatherConst() != null; ++i) node = node.getFatherConst();
return node;
}
