/*
DroidFish - An Android chess program.
Copyright (C) 2011 Peter Österlund, peterosterlund2@gmail.com
This program 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.
This program 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 this program. If not, see <http://www.gnu.org/licenses/>.
*/
package chess;
import java.io.DataInputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Calendar;
import java.util.Collections;
import java.util.GregorianCalendar;
import java.util.List;
import java.util.Locale;
import java.util.Map;
import java.util.Map.Entry;
import chess.Game.GameState;
import chess.TimeControlData.TimeControlField;
public class GameTree {
// Data from the seven tag roster (STR) part of the PGN standard
String event, site, date, round, white, black;
// Result is the last tag pair in the STR, but it is computed on demand from the game tree.
public Position startPos;
private String timeControl, whiteTimeControl, blackTimeControl;
// Non-standard tags
static private final class TagPair {
String tagName;
String tagValue;
}
private List<TagPair> tagPairs;
public Node rootNode;
public Node currentNode;
public Position currentPos; // Cached value. Computable from "currentNode".
private final PgnToken.PgnTokenReceiver gameStateListener;
/** Creates an empty GameTree starting at the standard start position.
* @param gameStateListener Optional tree change listener.
*/
public GameTree(PgnToken.PgnTokenReceiver gameStateListener) {
this.gameStateListener = gameStateListener;
try {
setStartPos(TextIO.readFEN(TextIO.startPosFEN));
} catch (ChessParseError e) {
}
}
final void setPlayerNames(String white, String black) {
this.white = white;
this.black = black;
updateListener();
}
/** Set start position. Drops the whole game tree. */
final void setStartPos(Position pos) {
event = "?";
site = "?";
{
Calendar now = GregorianCalendar.getInstance();
int year = now.get(Calendar.YEAR);
int month = now.get(Calendar.MONTH) + 1;
int day = now.get(Calendar.DAY_OF_MONTH);
date = String.format(Locale.US, "%04d.%02d.%02d", year, month, day);
}
round = "?";
white = "?";
black = "?";
startPos = pos;
timeControl = "?";
whiteTimeControl = "?";
blackTimeControl = "?";
tagPairs = new ArrayList<>();
rootNode = new Node();
currentNode = rootNode;
currentPos = new Position(startPos);
updateListener();
}
private void updateListener() {
if (gameStateListener != null)
gameStateListener.clear();
}
/** PgnTokenReceiver implementation that generates plain text PGN data. */
private static class PgnText implements PgnToken.PgnTokenReceiver {
private StringBuilder sb = new StringBuilder(256);
private String header = "";
private int prevType = PgnToken.EOF;
final String getPgnString() {
StringBuilder ret = new StringBuilder(4096);
ret.append(header);
ret.append('\n');
String[] words = sb.toString().split(" ");
int currLineLength = 0;
final int arrLen = words.length;
for (int i = 0; i < arrLen; i++) {
String word = words[i].trim();
int wordLen = word.length();
if (wordLen > 0) {
if (currLineLength == 0) {
ret.append(word);
currLineLength = wordLen;
} else if (currLineLength + 1 + wordLen >= 80) {
ret.append('\n');
ret.append(word);
currLineLength = wordLen;
} else {
ret.append(' ');
currLineLength++;
ret.append(word);
currLineLength += wordLen;
}
}
}
ret.append("\n\n");
return ret.toString();
}
@Override
public void processToken(Node node, int type, String token) {
if ( (prevType == PgnToken.RIGHT_BRACKET) &&
(type != PgnToken.LEFT_BRACKET)) {
header = sb.toString();
sb = new StringBuilder(4096);
}
switch (type) {
case PgnToken.STRING: {
sb.append(" \"");
int len = token.length();
for (int i = 0; i < len; i++) {
char c = token.charAt(i);
if ((c == '\\') || (c == '"')) {
sb.append('\\');
}
sb.append(c);
}
sb.append("\"");
break;
}
case PgnToken.INTEGER:
if ( (prevType != PgnToken.LEFT_PAREN) &&
(prevType != PgnToken.RIGHT_BRACKET))
sb.append(' ');
sb.append(token);
break;
case PgnToken.PERIOD:
sb.append('.');
break;
case PgnToken.ASTERISK:
sb.append(" *");
break;
case PgnToken.LEFT_BRACKET:
sb.append('[');
break;
case PgnToken.RIGHT_BRACKET:
sb.append("]\n");
break;
case PgnToken.LEFT_PAREN:
sb.append(" (");
break;
case PgnToken.RIGHT_PAREN:
sb.append(')');
break;
case PgnToken.NAG:
sb.append(" $");
sb.append(token);
break;
case PgnToken.SYMBOL:
if ((prevType != PgnToken.RIGHT_BRACKET) && (prevType != PgnToken.LEFT_BRACKET))
sb.append(' ');
sb.append(token);
break;
case PgnToken.COMMENT:
if ( (prevType != PgnToken.LEFT_PAREN) &&
(prevType != PgnToken.RIGHT_BRACKET))
sb.append(' ');
sb.append('{');
sb.append(token);
sb.append('}');
break;
case PgnToken.EOF:
break;
}
prevType = type;
}
@Override
public boolean isUpToDate() {
return true;
}
@Override
public void clear() {
}
@Override
public void setCurrent(Node node) {
}
}
/** Export game tree in PGN format. */
public final String toPGN(PGNOptions options) {
PgnText pgnText = new PgnText();
options.exp.pgnPromotions = true;
options.exp.pieceType = PGNOptions.PT_ENGLISH;
pgnTreeWalker(options, pgnText);
return pgnText.getPgnString();
}
/** Walks the game tree in PGN export order. */
public final void pgnTreeWalker(PGNOptions options, PgnToken.PgnTokenReceiver out) {
String pgnResultString = getPGNResultStringMainLine();
// Write seven tag roster
addTagPair(out, "Event", event);
addTagPair(out, "Site", site);
addTagPair(out, "Date", date);
addTagPair(out, "Round", round);
addTagPair(out, "White", white);
addTagPair(out, "Black", black);
addTagPair(out, "Result", pgnResultString);
// Write special tag pairs
String fen = TextIO.toFEN(startPos);
if (!fen.equals(TextIO.startPosFEN)) {
addTagPair(out, "FEN", fen);
addTagPair(out, "SetUp", "1");
}
if (!timeControl.equals("?"))
addTagPair(out, "TimeControl", timeControl);
if (!whiteTimeControl.equals("?"))
addTagPair(out, "WhiteTimeControl", whiteTimeControl);
if (!blackTimeControl.equals("?"))
addTagPair(out, "BlackTimeControl", blackTimeControl);
// Write other non-standard tag pairs
for (int i = 0; i < tagPairs.size(); i++)
addTagPair(out, tagPairs.get(i).tagName, tagPairs.get(i).tagValue);
// Write moveText section
MoveNumber mn = new MoveNumber(startPos.fullMoveCounter, startPos.whiteMove);
Node.addPgnData(out, rootNode, mn.prev(), options);
out.processToken(null, PgnToken.SYMBOL, pgnResultString);
out.processToken(null, PgnToken.EOF, null);
}
private void addTagPair(PgnToken.PgnTokenReceiver out, String tagName, String tagValue) {
out.processToken(null, PgnToken.LEFT_BRACKET, null);
out.processToken(null, PgnToken.SYMBOL, tagName);
out.processToken(null, PgnToken.STRING, tagValue);
out.processToken(null, PgnToken.RIGHT_BRACKET, null);
}
final static class PgnScanner {
String data;
int idx;
List<PgnToken> savedTokens;
PgnScanner(String pgn) {
savedTokens = new ArrayList<>();
// Skip "escape" lines, ie lines starting with a '%' character
StringBuilder sb = new StringBuilder();
int len = pgn.length();
boolean col0 = true;
for (int i = 0; i < len; i++) {
char c = pgn.charAt(i);
if (c == '%' && col0) {
while (i + 1 < len) {
char nextChar = pgn.charAt(i + 1);
if ((nextChar == '\n') || (nextChar == '\r'))
break;
i++;
}
col0 = true;
} else {
sb.append(c);
col0 = ((c == '\n') || (c == '\r'));
}
}
sb.append('\n'); // Terminating whitespace simplifies the tokenizer
data = sb.toString();
idx = 0;
}
final void putBack(PgnToken tok) {
savedTokens.add(tok);
}
final PgnToken nextToken() {
if (savedTokens.size() > 0) {
int len = savedTokens.size();
PgnToken ret = savedTokens.get(len - 1);
savedTokens.remove(len - 1);
return ret;
}
PgnToken ret = new PgnToken(PgnToken.EOF, null);
try {
while (true) {
char c = data.charAt(idx++);
if (Character.isWhitespace(c) || c == '\u00a0') {
// Skip
} else if (c == '.') {
ret.type = PgnToken.PERIOD;
break;
} else if (c == '*') {
ret.type = PgnToken.ASTERISK;
break;
} else if (c == '[') {
ret.type = PgnToken.LEFT_BRACKET;
break;
} else if (c == ']') {
ret.type = PgnToken.RIGHT_BRACKET;
break;
} else if (c == '(') {
ret.type = PgnToken.LEFT_PAREN;
break;
} else if (c == ')') {
ret.type = PgnToken.RIGHT_PAREN;
break;
} else if (c == '{') {
ret.type = PgnToken.COMMENT;
StringBuilder sb = new StringBuilder();
while ((c = data.charAt(idx++)) != '}') {
sb.append(c);
}
ret.token = sb.toString();
break;
} else if (c == ';') {
ret.type = PgnToken.COMMENT;
StringBuilder sb = new StringBuilder();
while (true) {
c = data.charAt(idx++);
if ((c == '\n') || (c == '\r'))
break;
sb.append(c);
}
ret.token = sb.toString();
break;
} else if (c == '"') {
ret.type = PgnToken.STRING;
StringBuilder sb = new StringBuilder();
while (true) {
c = data.charAt(idx++);
if (c == '"') {
break;
} else if (c == '\\') {
c = data.charAt(idx++);
}
sb.append(c);
}
ret.token = sb.toString();
break;
} else if (c == '$') {
ret.type = PgnToken.NAG;
StringBuilder sb = new StringBuilder();
while (true) {
c = data.charAt(idx++);
if (!Character.isDigit(c)) {
idx--;
break;
}
sb.append(c);
}
ret.token = sb.toString();
break;
} else { // Start of symbol or integer
ret.type = PgnToken.SYMBOL;
StringBuilder sb = new StringBuilder();
sb.append(c);
boolean onlyDigits = Character.isDigit(c);
final String term = ".*[](){;\"$";
while (true) {
c = data.charAt(idx++);
if (Character.isWhitespace(c) || (term.indexOf(c) >= 0)) {
idx--;
break;
}
sb.append(c);
if (!Character.isDigit(c))
onlyDigits = false;
}
if (onlyDigits) {
ret.type = PgnToken.INTEGER;
}
ret.token = sb.toString();
break;
}
}
} catch (StringIndexOutOfBoundsException e) {
ret.type = PgnToken.EOF;
}
return ret;
}
final PgnToken nextTokenDropComments() {
while (true) {
PgnToken tok = nextToken();
if (tok.type != PgnToken.COMMENT)
return tok;
}
}
}
/** Import PGN data. */
public final boolean readPGN(String pgn, PGNOptions options) throws ChessParseError {
PgnScanner scanner = new PgnScanner(pgn);
PgnToken tok = scanner.nextToken();
// Parse tag section
List<TagPair> tagPairs = new ArrayList<>();
while (tok.type == PgnToken.LEFT_BRACKET) {
TagPair tp = new TagPair();
tok = scanner.nextTokenDropComments();
if (tok.type != PgnToken.SYMBOL)
break;
tp.tagName = tok.token;
tok = scanner.nextTokenDropComments();
if (tok.type != PgnToken.STRING)
break;
tp.tagValue = tok.token;
tok = scanner.nextTokenDropComments();
if (tok.type != PgnToken.RIGHT_BRACKET) {
// In a well-formed PGN, there is nothing between the string
// and the right bracket, but broken headers with non-escaped
// " characters sometimes occur. Try to do something useful
// for such headers here.
PgnToken prevTok = new PgnToken(PgnToken.STRING, "");
while ((tok.type == PgnToken.STRING) || (tok.type == PgnToken.SYMBOL)) {
if (tok.type != prevTok.type)
tp.tagValue += '"';
if ((tok.type == PgnToken.SYMBOL) && (prevTok.type == PgnToken.SYMBOL))
tp.tagValue += ' ';
tp.tagValue += tok.token;
prevTok = tok;
tok = scanner.nextTokenDropComments();
}
}
tagPairs.add(tp);
tok = scanner.nextToken();
}
scanner.putBack(tok);
// Parse move section
Node gameRoot = new Node();
Node.parsePgn(scanner, gameRoot, options);
if (tagPairs.size() == 0) {
gameRoot.verifyChildren(TextIO.readFEN(TextIO.startPosFEN));
if (gameRoot.children.size() == 0)
return false;
}
// Store parsed data in GameTree
String fen = TextIO.startPosFEN;
int nTags = tagPairs.size();
for (int i = 0; i < nTags; i++) {
if (tagPairs.get(i).tagName.equals("FEN")) {
fen = tagPairs.get(i).tagValue;
}
}
setStartPos(TextIO.readFEN(fen));
String result = "";
for (int i = 0; i < nTags; i++) {
String name = tagPairs.get(i).tagName;
String val = tagPairs.get(i).tagValue;
if (name.equals("FEN") || name.equals("SetUp")) {
// Already handled
} else if (name.equals("Event")) {
event = val;
} else if (name.equals("Site")) {
site = val;
} else if (name.equals("Date")) {
date = val;
} else if (name.equals("Round")) {
round = val;
} else if (name.equals("White")) {
white = val;
} else if (name.equals("Black")) {
black = val;
} else if (name.equals("Result")) {
result = val;
} else if (name.equals("TimeControl")) {
timeControl = val;
} else if (name.equals("WhiteTimeControl")) {
whiteTimeControl = val;
} else if (name.equals("BlackTimeControl")) {
blackTimeControl = val;
} else {
this.tagPairs.add(tagPairs.get(i));
}
}
rootNode = gameRoot;
currentNode = rootNode;
// If result indicated draw by agreement or a resigned game,
// add that info to the game tree.
{
// Go to end of mainline
while (variations().size() > 0)
goForward(0);
GameState state = getGameState();
if (state == GameState.ALIVE)
addResult(result);
// Go back to the root
while (currentNode != rootNode)
goBack();
}
updateListener();
return true;
}
/** Add game result to the tree. currentNode must be at the end of the main line. */
private void addResult(String result) {
if (result.equals("1-0")) {
if (currentPos.whiteMove) {
currentNode.playerAction = "resign";
} else {
addMove("--", "resign", 0, "", "");
}
} else if (result.equals("0-1")) {
if (!currentPos.whiteMove) {
currentNode.playerAction = "resign";
} else {
addMove("--", "resign", 0, "", "");
}
} else if (result.equals("1/2-1/2") || result.equals("1/2")) {
currentNode.playerAction = "draw offer";
addMove("--", "draw accept", 0, "", "");
}
}
/** Serialize to output stream. */
public final void writeToStream(DataOutputStream dos) throws IOException {
dos.writeUTF(event);
dos.writeUTF(site);
dos.writeUTF(date);
dos.writeUTF(round);
dos.writeUTF(white);
dos.writeUTF(black);
dos.writeUTF(TextIO.toFEN(startPos));
dos.writeUTF(timeControl);
dos.writeUTF(whiteTimeControl);
dos.writeUTF(blackTimeControl);
int nTags = tagPairs.size();
dos.writeInt(nTags);
for (int i = 0; i < nTags; i++) {
dos.writeUTF(tagPairs.get(i).tagName);
dos.writeUTF(tagPairs.get(i).tagValue);
}
Node.writeToStream(dos, rootNode);
ArrayList<Integer> pathFromRoot = currentNode.getPathFromRoot();
int pathLen = pathFromRoot.size();
dos.writeInt(pathLen);
for (int i = 0; i < pathLen; i++)
dos.writeInt(pathFromRoot.get(i));
}
/** De-serialize from input stream. */
public final void readFromStream(DataInputStream dis, int version) throws IOException, ChessParseError {
event = dis.readUTF();
site = dis.readUTF();
date = dis.readUTF();
round = dis.readUTF();
white = dis.readUTF();
black = dis.readUTF();
startPos = TextIO.readFEN(dis.readUTF());
currentPos = new Position(startPos);
timeControl = dis.readUTF();
if (version >= 2) {
whiteTimeControl = dis.readUTF();
blackTimeControl = dis.readUTF();
} else {
whiteTimeControl = "?";
blackTimeControl = "?";
}
int nTags = dis.readInt();
tagPairs.clear();
for (int i = 0; i < nTags; i++) {
TagPair tp = new TagPair();
tp.tagName = dis.readUTF();
tp.tagValue = dis.readUTF();
tagPairs.add(tp);
}
rootNode = new Node();
Node.readFromStream(dis, rootNode);
currentNode = rootNode;
int pathLen = dis.readInt();
for (int i = 0; i < pathLen; i++)
goForward(dis.readInt());
updateListener();
}
/** Go backward in game tree. */
public final void goBack() {
if (currentNode.parent != null) {
currentPos.unMakeMove(currentNode.move, currentNode.ui);
currentNode = currentNode.parent;
}
}
/** Go forward in game tree.
* @param variation Which variation to follow. -1 to follow default variation.
*/
public final void goForward(int variation) {
goForward(variation, true);
}
public final void goForward(int variation, boolean updateDefault) {
if (currentNode.verifyChildren(currentPos))
updateListener();
if (variation < 0)
variation = currentNode.defaultChild;
int numChildren = currentNode.children.size();
if (variation >= numChildren)
variation = 0;
if (updateDefault)
currentNode.defaultChild = variation;
if (numChildren > 0) {
currentNode = currentNode.children.get(variation);
currentPos.makeMove(currentNode.move, currentNode.ui);
TextIO.fixupEPSquare(currentPos);
}
}
/** Go to given node in game tree.
* @return True if current node changed, false otherwise. */
public final boolean goNode(Node node) {
if (node == currentNode)
return false;
ArrayList<Integer> path = node.getPathFromRoot();
while (currentNode != rootNode)
goBack();
for (Integer c : path)
goForward(c);
return true;
}
/** List of possible continuation moves. */
public final ArrayList<Move> variations() {
if (currentNode.verifyChildren(currentPos))
updateListener();
ArrayList<Move> ret = new ArrayList<>();
for (Node child : currentNode.children)
ret.add(child.move);
return ret;
}
/** Add a move last in the list of variations.
* @return Move number in variations list. -1 if moveStr is not a valid move
*/
public final int addMove(String moveStr, String playerAction, int nag, String preComment, String postComment) {
if (currentNode.verifyChildren(currentPos))
updateListener();
int idx = currentNode.children.size();
Node node = new Node(currentNode, moveStr, playerAction, Integer.MIN_VALUE, nag, preComment, postComment);
Move move = TextIO.UCIstringToMove(moveStr);
ArrayList<Move> moves = null;
if (move == null) {
moves = MoveGen.instance.legalMoves(currentPos);
move = TextIO.stringToMove(currentPos, moveStr, moves);
}
if (move == null)
return -1;
if (moves == null)
moves = MoveGen.instance.legalMoves(currentPos);
node.moveStr = TextIO.moveToString(currentPos, move, false, moves);
node.move = move;
node.ui = new UndoInfo();
currentNode.children.add(node);
updateListener();
return idx;
}
/** Move a variation in the ordered list of variations. */
public final void reorderVariation(int varNo, int newPos) {
if (currentNode.verifyChildren(currentPos))
updateListener();
int nChild = currentNode.children.size();
if ((varNo < 0) || (varNo >= nChild) || (newPos < 0) || (newPos >= nChild))
return;
Node var = currentNode.children.get(varNo);
currentNode.children.remove(varNo);
currentNode.children.add(newPos, var);
int newDef = currentNode.defaultChild;
if (varNo == newDef) {
newDef = newPos;
} else {
if (varNo < newDef) newDef--;
if (newPos <= newDef) newDef++;
}
currentNode.defaultChild = newDef;
updateListener();
}
/** Delete a variation. */
public final void deleteVariation(int varNo) {
if (currentNode.verifyChildren(currentPos))
updateListener();
int nChild = currentNode.children.size();
if ((varNo < 0) || (varNo >= nChild))
return;
currentNode.children.remove(varNo);
if (varNo == currentNode.defaultChild) {
currentNode.defaultChild = 0;
} else if (varNo < currentNode.defaultChild) {
currentNode.defaultChild--;
}
updateListener();
}
/** Get linear game history, using default variations at branch points. */
public final Pair<List<Node>, Integer> getMoveList() {
List<Node> ret = new ArrayList<>();
Node node = currentNode;
while (node != rootNode) {
ret.add(node);
node = node.parent;
}
Collections.reverse(ret);
int numMovesPlayed = ret.size();
node = currentNode;
Position pos = new Position(currentPos);
UndoInfo ui = new UndoInfo();
boolean changed = false;
while (true) {
if (node.verifyChildren(pos))
changed = true;
if (node.defaultChild >= node.children.size())
break;
Node child = node.children.get(node.defaultChild);
ret.add(child);
pos.makeMove(child.move, ui);
node = child;
}
if (changed)
updateListener();
return new Pair<>(ret, numMovesPlayed);
}
final void setRemainingTime(int remaining) {
currentNode.remainingTime = remaining;
}
final int getRemainingTime(boolean whiteMove, int initialTime) {
final int undef = Integer.MIN_VALUE;
int remainingTime = undef;
Node node = currentNode;
boolean wtm = currentPos.whiteMove;
while (true) {
if (wtm != whiteMove) { // If wtm in current mode, black made last move
remainingTime = node.remainingTime;
if (remainingTime != undef)
break;
}
Node parent = node.parent;
if (parent == null)
break;
wtm = !wtm;
node = parent;
}
if (remainingTime == undef) {
remainingTime = initialTime;
}
return remainingTime;
}
final GameState getGameState() {
Position pos = currentPos;
String action = currentNode.playerAction;
if (action.equals("resign")) {
// Player made null move to resign, causing whiteMove to toggle
return pos.whiteMove ? GameState.RESIGN_BLACK : GameState.RESIGN_WHITE;
}
ArrayList<Move> moves = new MoveGen().legalMoves(pos);
if (moves.size() == 0) {
if (MoveGen.inCheck(pos)) {
return pos.whiteMove ? GameState.BLACK_MATE : GameState.WHITE_MATE;
} else {
return pos.whiteMove ? GameState.WHITE_STALEMATE : GameState.BLACK_STALEMATE;
}
}
if (insufficientMaterial(pos)) {
return GameState.DRAW_NO_MATE;
}
if (action.startsWith("draw accept")) {
return GameState.DRAW_AGREE;
}
if (action.startsWith("draw rep")) {
return GameState.DRAW_REP;
}
if (action.startsWith("draw 50")) {
return GameState.DRAW_50;
}
return GameState.ALIVE;
}
/** Get PGN result string corresponding to the current position. */
public final String getPGNResultString() {
String gameResult = "*";
switch (getGameState()) {
case ALIVE:
break;
case WHITE_MATE:
case RESIGN_BLACK:
gameResult = "1-0";
break;
case BLACK_MATE:
case RESIGN_WHITE:
gameResult = "0-1";
break;
case WHITE_STALEMATE:
case BLACK_STALEMATE:
case DRAW_REP:
case DRAW_50:
case DRAW_NO_MATE:
case DRAW_AGREE:
gameResult = "1/2-1/2";
break;
}
return gameResult;
}
/** Evaluate PGN result string at the end of the main line. */
public final String getPGNResultStringMainLine() {
List<Integer> currPath = new ArrayList<>();
while (currentNode != rootNode) {
Node child = currentNode;
goBack();
int childNum = currentNode.children.indexOf(child);
currPath.add(childNum);
}
while (variations().size() > 0)
goForward(0, false);
String res = getPGNResultString();
while (currentNode != rootNode)
goBack();
for (int i = currPath.size() - 1; i >= 0; i--)
goForward(currPath.get(i), false);
return res;
}
private static boolean insufficientMaterial(Position pos) {
if (pos.nPieces(Piece.WQUEEN) > 0) return false;
if (pos.nPieces(Piece.WROOK) > 0) return false;
if (pos.nPieces(Piece.WPAWN) > 0) return false;
if (pos.nPieces(Piece.BQUEEN) > 0) return false;
if (pos.nPieces(Piece.BROOK) > 0) return false;
if (pos.nPieces(Piece.BPAWN) > 0) return false;
int wb = pos.nPieces(Piece.WBISHOP);
int wn = pos.nPieces(Piece.WKNIGHT);
int bb = pos.nPieces(Piece.BBISHOP);
int bn = pos.nPieces(Piece.BKNIGHT);
if (wb + wn + bb + bn <= 1) {
return true; // King + bishop/knight vs king is draw
}
if (wn + bn == 0) {
// Only bishops. If they are all on the same color, the position is a draw.
boolean bSquare = false;
boolean wSquare = false;
for (int x = 0; x < 8; x++) {
for (int y = 0; y < 8; y++) {
int p = pos.getPiece(Position.getSquare(x, y));
if ((p == Piece.BBISHOP) || (p == Piece.WBISHOP)) {
if (Position.darkSquare(x, y)) {
bSquare = true;
} else {
wSquare = true;
}
}
}
}
if (!bSquare || !wSquare) {
return true;
}
}
return false;
}
/** Keep track of current move and side to move. Used for move number printing. */
private static final class MoveNumber {
final int moveNo;
final boolean wtm; // White to move
MoveNumber(int moveNo, boolean wtm) {
this.moveNo = moveNo;
this.wtm = wtm;
}
public final MoveNumber next() {
if (wtm) return new MoveNumber(moveNo, false);
else return new MoveNumber(moveNo + 1, true);
}
public final MoveNumber prev() {
if (wtm) return new MoveNumber(moveNo - 1, false);
else return new MoveNumber(moveNo, true);
}
}
/**
* A node object represents a position in the game tree.
* The position is defined by the move that leads to the position from the parent position.
* The root node is special in that it doesn't have a move.
*/
public static class Node {
String moveStr; // String representation of move leading to this node. Empty string in root node.
public Move move; // Computed on demand for better PGN parsing performance.
// Subtrees of invalid moves will be dropped when detected.
// Always valid for current node.
private UndoInfo ui; // Computed when move is computed
String playerAction; // Player action. Draw claim/offer/accept or resign.
int remainingTime; // Remaining time in ms for side that played moveStr, or INT_MIN if unknown.
int nag; // Numeric annotation glyph
String preComment; // Comment before move
String postComment; // Comment after move
private Node parent; // Null if root node
int defaultChild;
private ArrayList<Node> children;
public Node() {
this.moveStr = "";
this.move = null;
this.ui = null;
this.playerAction = "";
this.remainingTime = Integer.MIN_VALUE;
this.parent = null;
this.children = new ArrayList<>();
this.defaultChild = 0;
this.nag = 0;
this.preComment = "";
this.postComment = "";
}
public Node(Node parent, String moveStr, String playerAction, int remainingTime, int nag,
String preComment, String postComment) {
this.moveStr = moveStr;
this.move = null;
this.ui = null;
this.playerAction = playerAction;
this.remainingTime = remainingTime;
this.parent = parent;
this.children = new ArrayList<>();
this.defaultChild = 0;
this.nag = nag;
this.preComment = preComment;
this.postComment = postComment;
}
public Node getParent() {
return parent;
}
/** nodePos must represent the same position as this Node object. */
private boolean verifyChildren(Position nodePos) {
return verifyChildren(nodePos, null);
}
private boolean verifyChildren(Position nodePos, ArrayList<Move> moves) {
boolean anyToRemove = false;
for (Node child : children) {
if (child.move == null) {
if (moves == null)
moves = MoveGen.instance.legalMoves(nodePos);
Move move = TextIO.stringToMove(nodePos, child.moveStr, moves);
if (move != null) {
child.moveStr = TextIO.moveToString(nodePos, move, false, moves);
child.move = move;
child.ui = new UndoInfo();
} else {
anyToRemove = true;
}
}
}
if (anyToRemove) {
ArrayList<Node> validChildren = new ArrayList<>();
for (Node child : children)
if (child.move != null)
validChildren.add(child);
children = validChildren;
}
return anyToRemove;
}
final ArrayList<Integer> getPathFromRoot() {
ArrayList<Integer> ret = new ArrayList<>(64);
Node node = this;
while (node.parent != null) {
ret.add(node.getChildNo());
node = node.parent;
}
Collections.reverse(ret);
return ret;
}
/** Return this node's position in the parent node child list. */
public final int getChildNo() {
Node p = parent;
for (int i = 0; i < p.children.size(); i++)
if (p.children.get(i) == this)
return i;
throw new RuntimeException();
}
static void writeToStream(DataOutputStream dos, Node node) throws IOException {
while (true) {
dos.writeUTF(node.moveStr);
if (node.move != null) {
dos.writeByte(node.move.from);
dos.writeByte(node.move.to);
dos.writeByte(node.move.promoteTo);
} else {
dos.writeByte(-1);
}
dos.writeUTF(node.playerAction);
dos.writeInt(node.remainingTime);
dos.writeInt(node.nag);
dos.writeUTF(node.preComment);
dos.writeUTF(node.postComment);
dos.writeInt(node.defaultChild);
int nChildren = node.children.size();
dos.writeInt(nChildren);
if (nChildren == 0)
break;
for (int i = 1; i < nChildren; i++) {
writeToStream(dos, node.children.get(i));
}
node = node.children.get(0);
}
}
static void readFromStream(DataInputStream dis, Node node) throws IOException {
while (true) {
node.moveStr = dis.readUTF();
int from = dis.readByte();
if (from >= 0) {
int to = dis.readByte();
int prom = dis.readByte();
node.move = new Move(from, to, prom);
node.ui = new UndoInfo();
}
node.playerAction = dis.readUTF();
node.remainingTime = dis.readInt();
node.nag = dis.readInt();
node.preComment = dis.readUTF();
node.postComment = dis.readUTF();
node.defaultChild = dis.readInt();
int nChildren = dis.readInt();
if (nChildren == 0)
break;
for (int i = 1; i < nChildren; i++) {
Node child = new Node();
child.parent = node;
readFromStream(dis, child);
node.children.add(child);
}
Node child = new Node();
child.parent = node;
node.children.add(0, child);
node = child;
}
}
/** Export whole tree rooted at "node" in PGN format. */
public static void addPgnData(PgnToken.PgnTokenReceiver out, Node node,
MoveNumber moveNum, PGNOptions options) {
boolean needMoveNr = node.addPgnDataOneNode(out, moveNum, true, options);
while (true) {
int nChild = node.children.size();
if (nChild == 0)
break;
MoveNumber nextMN = moveNum.next();
needMoveNr = node.children.get(0).addPgnDataOneNode(out, nextMN, needMoveNr, options);
if (options.exp.variations) {
for (int i = 1; i < nChild; i++) {
out.processToken(node, PgnToken.LEFT_PAREN, null);
addPgnData(out, node.children.get(i), nextMN, options);
out.processToken(node, PgnToken.RIGHT_PAREN, null);
needMoveNr = true;
}
}
node = node.children.get(0);
moveNum = moveNum.next();
}
}
/** Export this node in PGN (or display text) format. */
private boolean addPgnDataOneNode(PgnToken.PgnTokenReceiver out, MoveNumber mn,
boolean needMoveNr, PGNOptions options) {
if ((preComment.length() > 0) && options.exp.comments) {
out.processToken(this, PgnToken.COMMENT, preComment);
needMoveNr = true;
}
if (moveStr.length() > 0) {
boolean nullSkip = moveStr.equals("--") && (playerAction.length() > 0) && !options.exp.playerAction;
if (!nullSkip) {
if (mn.wtm) {
out.processToken(this, PgnToken.INTEGER, Integer.valueOf(mn.moveNo).toString());
out.processToken(this, PgnToken.PERIOD, null);
} else {
if (needMoveNr) {
out.processToken(this, PgnToken.INTEGER, Integer.valueOf(mn.moveNo).toString());
for (int i = 0; i < 3; i++)
out.processToken(this, PgnToken.PERIOD, null);
}
}
String str = moveStr;
if (options.exp.pgnPromotions && (move != null) && (move.promoteTo != Piece.EMPTY))
str = TextIO.pgnPromotion(str);
out.processToken(this, PgnToken.SYMBOL, str);
needMoveNr = false;
}
}
if ((nag > 0) && options.exp.nag) {
out.processToken(this, PgnToken.NAG, Integer.valueOf(nag).toString());
if (options.exp.moveNrAfterNag)
needMoveNr = true;
}
if ((postComment.length() > 0) && options.exp.comments) {
out.processToken(this, PgnToken.COMMENT, postComment);
needMoveNr = true;
}
if ((playerAction.length() > 0) && options.exp.playerAction) {
addExtendedInfo(out, "playeraction", playerAction);
needMoveNr = true;
}
if ((remainingTime != Integer.MIN_VALUE) && options.exp.clockInfo) {
addExtendedInfo(out, "clk", getTimeStr(remainingTime));
needMoveNr = true;
}
return needMoveNr;
}
private void addExtendedInfo(PgnToken.PgnTokenReceiver out,
String extCmd, String extData) {
out.processToken(this, PgnToken.COMMENT, "[%" + extCmd + " " + extData + "]");
}
private static String getTimeStr(int remainingTime) {
int secs = (int)Math.floor((remainingTime + 999) / 1000.0);
boolean neg = false;
if (secs < 0) {
neg = true;
secs = -secs;
}
int mins = secs / 60;
secs -= mins * 60;
int hours = mins / 60;
mins -= hours * 60;
StringBuilder ret = new StringBuilder();
if (neg) ret.append('-');
if (hours < 10) ret.append('0');
ret.append(hours);
ret.append(':');
if (mins < 10) ret.append('0');
ret.append(mins);
ret.append(':');
if (secs < 10) ret.append('0');
ret.append(secs);
return ret.toString();
}
private Node addChild(Node child) {
child.parent = this;
children.add(child);
return child;
}
public static void parsePgn(PgnScanner scanner, Node node, PGNOptions options) {
Node nodeToAdd = new Node();
boolean moveAdded = false;
while (true) {
PgnToken tok = scanner.nextToken();
switch (tok.type) {
case PgnToken.INTEGER:
case PgnToken.PERIOD:
break;
case PgnToken.LEFT_PAREN:
if (moveAdded) {
node = node.addChild(nodeToAdd);
nodeToAdd = new Node();
moveAdded = false;
}
if ((node.parent != null) && options.imp.variations) {
parsePgn(scanner, node.parent, options);
} else {
int nestLevel = 1;
while (nestLevel > 0) {
switch (scanner.nextToken().type) {
case PgnToken.LEFT_PAREN: nestLevel++; break;
case PgnToken.RIGHT_PAREN: nestLevel--; break;
case PgnToken.EOF: return; // Broken PGN file. Just give up.
}
}
}
break;
case PgnToken.NAG:
if (moveAdded && options.imp.nag) { // NAG must be after move
try {
nodeToAdd.nag = Integer.parseInt(tok.token);
} catch (NumberFormatException e) {
nodeToAdd.nag = 0;
}
}
break;
case PgnToken.SYMBOL:
if (tok.token.equals("1-0") || tok.token.equals("0-1") || tok.token.equals("1/2-1/2")) {
if (moveAdded) node.addChild(nodeToAdd);
return;
}
char lastChar = tok.token.charAt(tok.token.length() - 1);
if (lastChar == '+')
tok.token = tok.token.substring(0, tok.token.length() - 1);
if ((lastChar == '!') || (lastChar == '?')) {
int movLen = tok.token.length() - 1;
while (movLen > 0) {
char c = tok.token.charAt(movLen - 1);
if ((c == '!') || (c == '?'))
movLen--;
else
break;
}
String ann = tok.token.substring(movLen);
tok.token = tok.token.substring(0, movLen);
int nag = 0;
if (ann.equals("!")) nag = 1;
else if (ann.equals("?")) nag = 2;
else if (ann.equals("!!")) nag = 3;
else if (ann.equals("??")) nag = 4;
else if (ann.equals("!?")) nag = 5;
else if (ann.equals("?!")) nag = 6;
if (nag > 0)
scanner.putBack(new PgnToken(PgnToken.NAG, Integer.valueOf(nag).toString()));
}
if (tok.token.length() > 0) {
if (moveAdded) {
node = node.addChild(nodeToAdd);
nodeToAdd = new Node();
moveAdded = false;
}
nodeToAdd.moveStr = tok.token;
moveAdded = true;
}
break;
case PgnToken.COMMENT:
try {
while (true) {
Pair<String,String> ret = extractExtInfo(tok.token, "clk");
tok.token = ret.first;
String cmdPars = ret.second;
if (cmdPars == null)
break;
nodeToAdd.remainingTime = parseTimeString(cmdPars);
}
while (true) {
Pair<String,String> ret = extractExtInfo(tok.token, "playeraction");
tok.token = ret.first;
String cmdPars = ret.second;
if (cmdPars == null)
break;
nodeToAdd.playerAction = cmdPars;
}
} catch (IndexOutOfBoundsException e) {
}
if (options.imp.comments) {
if (moveAdded)
nodeToAdd.postComment += tok.token;
else
nodeToAdd.preComment += tok.token;
}
break;
case PgnToken.ASTERISK:
case PgnToken.LEFT_BRACKET:
case PgnToken.RIGHT_BRACKET:
case PgnToken.STRING:
case PgnToken.RIGHT_PAREN:
case PgnToken.EOF:
if (moveAdded) node.addChild(nodeToAdd);
return;
}
}
}
private static Pair<String, String> extractExtInfo(String comment, String cmd) {
comment = comment.replaceAll("\n|\r|\t", " ");
String remaining = comment;
String param = null;
String match = "[%" + cmd + " ";
int start = comment.indexOf(match);
if (start >= 0) {
int end = comment.indexOf("]", start);
if (end >= 0) {
remaining = comment.substring(0, start) + comment.substring(end + 1);
param = comment.substring(start + match.length(), end);
}
}
return new Pair<>(remaining, param);
}
/** Convert hh:mm:ss to milliseconds */
private static int parseTimeString(String str) {
str = str.trim();
int ret = 0;
boolean neg = false;
int i = 0;
if (str.charAt(0) == '-') {
neg = true;
i++;
}
int num = 0;
final int len = str.length();
for ( ; i < len; i++) {
char c = str.charAt(i);
if ((c >= '0') && (c <= '9')) {
num = num * 10 + c - '0';
} else if (c == ':') {
ret += num;
num = 0;
ret *= 60;
}
}
ret += num;
ret *= 1000;
if (neg)
ret = -ret;
return ret;
}
public static String nagStr(int nag) {
switch (nag) {
case 1: return "!";
case 2: return "?";
case 3: return "!!";
case 4: return "??";
case 5: return "!?";
case 6: return "?!";
case 11: return " =";
case 13: return " ∞";
case 14: return " +/=";
case 15: return " =/+";
case 16: return " +/-";
case 17: return " -/+";
case 18: return " +-";
case 19: return " -+";
default: return "";
}
}
public static int strToNag(String str) {
if (str.equals("!")) return 1;
else if (str.equals("?")) return 2;
else if (str.equals("!!")) return 3;
else if (str.equals("??")) return 4;
else if (str.equals("!?")) return 5;
else if (str.equals("?!")) return 6;
else if (str.equals("=")) return 11;
else if (str.equals("∞")) return 13;
else if (str.equals("+/=")) return 14;
else if (str.equals("=/+")) return 15;
else if (str.equals("+/-")) return 16;
else if (str.equals("-/+")) return 17;
else if (str.equals("+-")) return 18;
else if (str.equals("-+")) return 19;
else {
try {
str = str.replace("$", "");
int nag = Integer.parseInt(str);
return nag;
} catch (NumberFormatException nfe) {
}
return 0;
}
}
}
/** Set PGN header tags and values. Setting a non-required
* tag to null causes it to be removed.
* @return True if game result changes, false otherwise. */
boolean setHeaders(Map<String,String> headers) {
boolean resultChanged = false;
for (Entry<String, String> entry : headers.entrySet()) {
String tag = entry.getKey();
String val = entry.getValue();
if (tag.equals("Event")) event = val;
else if (tag.equals("Site")) site = val;
else if (tag.equals("Date")) date = val;
else if (tag.equals("Round")) round = val;
else if (tag.equals("White")) white = val;
else if (tag.equals("Black")) black = val;
else if (tag.equals("Result")) {
List<Integer> currPath = new ArrayList<>();
while (currentNode != rootNode) {
Node child = currentNode;
goBack();
int childNum = currentNode.children.indexOf(child);
currPath.add(childNum);
}
while (variations().size() > 0)
goForward(0, false);
if (!val.equals(getPGNResultString())) {
resultChanged = true;
GameState state = getGameState();
switch (state) {
case ALIVE:
case DRAW_50:
case DRAW_AGREE:
case DRAW_REP:
case RESIGN_BLACK:
case RESIGN_WHITE:
currentNode.playerAction = "";
if ("--".equals(currentNode.moveStr)) {
Node child = currentNode;
goBack();
int childNum = currentNode.children.indexOf(child);
deleteVariation(childNum);
}
addResult(val);
break;
default:
break;
}
}
while (currentNode != rootNode)
goBack();
for (int i = currPath.size() - 1; i >= 0; i--)
goForward(currPath.get(i), false);
} else {
if (val != null) {
boolean found = false;
for (TagPair t : tagPairs) {
if (t.tagName.equals(tag)) {
t.tagValue = val;
found = true;
break;
}
}
if (!found) {
TagPair tp = new TagPair();
tp.tagName = tag;
tp.tagValue = val;
tagPairs.add(tp);
}
} else {
for (int i = 0; i < tagPairs.size(); i++) {
if (tagPairs.get(i).tagName.equals(tag)) {
tagPairs.remove(i);
break;
}
}
}
}
}
return resultChanged;
}
/** Get PGN header tags and values. */
public void getHeaders(Map<String,String> headers) {
headers.put("Event", event);
headers.put("Site", site);
headers.put("Date", date);
headers.put("Round", round);
headers.put("White", white);
headers.put("Black", black);
headers.put("Result", getPGNResultStringMainLine());
if (!timeControl.equals("?"))
headers.put("TimeControl", timeControl);
if (!whiteTimeControl.equals("?"))
headers.put("WhiteTimeControl", whiteTimeControl);
if (!blackTimeControl.equals("?"))
headers.put("BlackTimeControl", blackTimeControl);
for (int i = 0; i < tagPairs.size(); i++) {
TagPair tp = tagPairs.get(i);
headers.put(tp.tagName, tp.tagValue);
}
}
private ArrayList<TimeControlField> stringToTCFields(String tcStr) {
String[] fields = tcStr.split(":");
int nf = fields.length;
ArrayList<TimeControlField> ret = new ArrayList<>(nf);
for (int i = 0; i < nf; i++) {
String f = fields[i].trim();
if (f.equals("?") || f.equals("-") || f.contains("*")) {
// Not supported
} else {
try {
int moves = 0;
int time = 0;
int inc = 0;
int idx = f.indexOf('/');
if (idx > 0)
moves = Integer.parseInt(f.substring(0, idx).trim());
if (idx >= 0)
f = f.substring(idx+1);
idx = f.indexOf('+');
if (idx >= 0) {
if (idx > 0)
time = (int)(Double.parseDouble(f.substring(0, idx).trim())*1e3);
if (idx >= 0)
f = f.substring(idx+1);
inc = (int)(Double.parseDouble(f.trim())*1e3);
} else {
time = (int)(Double.parseDouble(f.trim())*1e3);
}
ret.add(new TimeControlField(time, moves, inc));
} catch (NumberFormatException ex) {
// Invalid syntax, ignore
}
}
}
return ret;
}
private String tcFieldsToString(ArrayList<TimeControlField> tcFields) {
StringBuilder sb = new StringBuilder();
int nf = tcFields.size();
for (int i = 0; i < nf; i++) {
if (i > 0)
sb.append(':');
TimeControlField t = tcFields.get(i);
if (t.movesPerSession > 0) {
sb.append(t.movesPerSession);
sb.append('/');
}
sb.append(t.timeControl / 1000);
int ms = t.timeControl % 1000;
if (ms > 0) {
sb.append('.');
sb.append(String.format(Locale.US, "%03d", ms));
}
if (t.increment > 0) {
sb.append('+');
sb.append(t.increment / 1000);
ms = t.increment % 1000;
if (ms > 0) {
sb.append('.');
sb.append(String.format(Locale.US, "%03d", ms));
}
}
}
return sb.toString();
}
/** Get time control data, or null if not present. */
public TimeControlData getTimeControlData() {
if (!whiteTimeControl.equals("?") && !blackTimeControl.equals("?")) {
ArrayList<TimeControlField> tcW = stringToTCFields(whiteTimeControl);
ArrayList<TimeControlField> tcB = stringToTCFields(blackTimeControl);
if (!tcW.isEmpty() && !tcB.isEmpty()) {
TimeControlData tcData = new TimeControlData();
tcData.tcW = tcW;
tcData.tcB = tcB;
return tcData;
}
}
if (!timeControl.equals("?")) {
ArrayList<TimeControlField> tc = stringToTCFields(timeControl);
if (!tc.isEmpty()) {
TimeControlData tcData = new TimeControlData();
tcData.tcW = tc;
tcData.tcB = tc;
return tcData;
}
}
return null;
}
public void setTimeControlData(TimeControlData tcData) {
if (tcData.isSymmetric()) {
timeControl = tcFieldsToString(tcData.tcW);
whiteTimeControl = "?";
blackTimeControl = "?";
} else {
whiteTimeControl = tcFieldsToString(tcData.tcW);
blackTimeControl = tcFieldsToString(tcData.tcB);
timeControl = "?";
}
}
}