private static function doRank(MoveInterface $move, GameInterface $game, MoveCalculatorInterface $moveCalculator, &$score = 1)
{
MoveHelper::enrich($move, $game);
switch ($move->getType()) {
case MoveInterface::TYPE_CAPTURE:
case MoveInterface::TYPE_CAPTURE_EN_PASSANT:
$score = 50;
break;
}
$board = $game->getBoard();
if ($moveCalculator->controlsCenter($move, $board)) {
$score += 15;
}
if ($moveCalculator->avoidsCapture($move, $board)) {
$score += 25;
} elseif ($moveCalculator->causesCapture($move, $board)) {
$score -= 25;
}
$opposingColor = $move->getPiece()->getColor() === Color::WHITE ? Color::BLACK : Color::WHITE;
$mockedBoard = $moveCalculator->mockMove($move, $board);
if ($moveCalculator->isChecked($opposingColor, $mockedBoard)) {
if ($moveCalculator->isCheckmated($opposingColor, $mockedBoard)) {
return 100;
}
return 99;
}
if ($score < 1) {
return 1;
}
return $score;
}
/**
* @param string $notation
* @param GameInterface $game
* @param array $parsed
*
* @return int
*
* @throws InvalidNotationException
*/
private function parseFrom($notation, GameInterface $game, array $parsed)
{
$enPassant = false;
$capture = false;
switch ($parsed['piece_type']) {
case PieceInterface::TYPE_PAWN:
if (substr($notation, -4) === 'e.p.') {
$enPassant = true;
} elseif (substr($notation, 1, 1) === 'x') {
// calculate 'from' for capture by pawn (diagonally)
$capture = true;
} else {
// calculate 'from' for forward move by pawn
}
break;
default:
// non-pawn calculation, depends on type
break;
}
$finalMove = null;
$criteria = ['piece_color' => $parsed['color'], 'piece_type' => $parsed['piece_type']];
if (strlen($notation) > 3 && in_array(substr($notation, 1, 1), ['a', 'b', 'c', 'd', 'e', 'f', 'g', 'h'])) {
$criteria['column'] = BoardHelper::columnLetterToNumber(substr($notation, 1, 1));
}
$possiblePieceMoves = $this->moveCalculator->possibleMovesTo($parsed['to'], $game->getBoard(), $criteria);
foreach ($possiblePieceMoves as $move) {
MoveHelper::enrich($move, $game);
if ($enPassant === true && $move->getType() !== MoveInterface::TYPE_CAPTURE_EN_PASSANT) {
continue;
} elseif ($capture === true && $move->getType() !== MoveInterface::TYPE_CAPTURE) {
continue;
}
if ($finalMove !== null) {
throw new InvalidNotationException(sprintf('Multiple moves found starting from %s and ending on %s, you should make your notation more specific (criteria: %s)', $finalMove->getFromLabel(), $finalMove->getToLabel(), json_encode($criteria)));
}
$finalMove = $move;
}
if ($finalMove === null) {
throw new InvalidNotationException(sprintf('There are no moves to make to this position: %s (criteria: %s)', $parsed['to'], json_encode($criteria, true)));
}
return $finalMove->getFrom();
}
/**
* {@inheritdoc}
*/
public function doEngineMove(MoveCalculator $moveCalculator)
{
$currentPlayer = $this->getCurrentPlayer();
if ($currentPlayer->isHuman()) {
throw new \LogicException('Can\\t make an engine-move with a human player');
}
$possibleMoves = $moveCalculator->possibleMovesBy($currentPlayer->getColor(), $this->getBoard());
if (empty($possibleMoves)) {
throw new \RuntimeException('Failed to find a move for the engine... probably because this scenario wasn\'t worked out yet');
}
$highestRankingMove = MoveRanker::best($possibleMoves, $this, $moveCalculator);
MoveHelper::apply($highestRankingMove, $this);
$this->addState($this->createStateFromMove($highestRankingMove));
return $highestRankingMove;
}