public function generatePreList()
{
$temp = new ChessBoard();
$aboard = new ChessBoard();
$moves = array();
$output = array();
$moves[] = array(1, -1);
$moves[] = array(1, 0);
$moves[] = array(1, 1);
$moves[] = array(-1, 1);
$moves[] = array(-1, -1);
$moves[] = array(-1, 0);
$moves[] = array(0, 1);
$moves[] = array(0, -1);
foreach ($moves as $move) {
$output = array_merge($output, $this->addBoard($this->x, $this->y, $move));
}
//the rest is castling conditions
if ($this->typecode == ChessBoard::$WHITEKING) {
//white king castling to the left
if ($this->x == 5 && $this->y == 1 && $this->board->get(4, 1) == -1 && $this->board->get(3, 1) == -1 && $this->board->get(2, 1) == -1 && $this->board->get(1, 1) == ChessBoard::$WHITEROOK && !($this->board->castleData() & 64) && !($this->board->castleData() & 32)) {
$aboard->copy($this->board);
$aboard->changeTurn();
if ($this->recurse && !kingKillable("k,1,1," + $aboard->toString()) && !leftCastleThroughCheck($this->board)) {
$temp->copy($this->board);
$temp->set(1, 1, -1);
$temp->set(3, 1, ChessBoard::$WHITEKING);
$temp->set(4, 1, ChessBoard::$WHITEROOK);
$temp->set(5, 1, -1);
$temp->setLastMove(5, 1, 3, 1);
$temp->changeTurn();
$temp->checkKingRookHome();
$output[] = $temp->toString();
}
}
// white king castling to the right
if ($this->x == 5 && $this->y == 1 && $this->board->get(6, 1) == -1 && $this->board->get(7, 1) == -1 && $this->board->get(8, 1) == ChessBoard::$WHITEROOK && !($this->board->castleData() & 64) && !($this->board->castleData() & 16)) {
$aboard->copy($this->board);
$aboard->changeTurn();
if ($this->recurse && !kingKillable("k,1,1," + $aboard->toString()) && !rightCastleThroughCheck($this->board)) {
$temp->copy($this->board);
$temp->set(8, 1, -1);
$temp->set(7, 1, ChessBoard::$WHITEKING);
$temp->set(6, 1, ChessBoard::$WHITEROOK);
$temp->set(5, 1, -1);
$temp->setLastMove(5, 1, 7, 1);
$temp->changeTurn();
$temp->checkKingRookHome();
$output[] = $temp->toString();
}
}
}
if ($this->typecode == ChessBoard::$BLACKKING) {
// black king castling to the left
if ($this->x == 5 && $this->y == 8 && $this->board->get(4, 8) == -1 && $this->board->get(3, 8) == -1 && $this->board->get(2, 8) == -1 && $this->board->get(1, 8) == ChessBoard::$BLACKROOK && !($this->board->castleData() & 4) && !($this->board->castleData() & 2)) {
$aboard->copy($this->board);
$aboard->changeTurn();
if ($this->recurse && !kingKillable("k,1,1," + $aboard->toString()) && !leftCastleThroughCheck($this->board)) {
$temp->copy($this->board);
$temp->set(1, 8, -1);
$temp->set(3, 8, ChessBoard::$BLACKKING);
$temp->set(4, 8, ChessBoard::$BLACKROOK);
$temp->set(5, 8, -1);
$temp->setLastMove(5, 8, 3, 8);
$temp->changeTurn();
$temp->checkKingRookHome();
$output[] = $temp->toString();
}
}
// black king castling to the right
if ($this->x == 5 && $this->y == 8 && $this->board->get(6, 8) == -1 && $this->board->get(7, 8) == -1 && $this->board->get(8, 8) == ChessBoard::$BLACKROOK && !($this->board->castleData() & 4) && !($this->board->castleData() & 1)) {
$aboard->copy($this->board);
$aboard->changeTurn();
if ($this->recurse && !kingKillable("k,1,1," + $aboard->toString()) && !rightCastleThroughCheck($this->board)) {
$temp->copy($this->board);
$temp->set(8, 8, -1);
$temp->set(7, 8, ChessBoard::$BLACKKING);
$temp->set(6, 8, ChessBoard::$BLACKROOK);
$temp->set(5, 8, -1);
$temp->setLastMove(5, 8, 7, 8);
$temp->changeTurn();
$temp->checkKingRookHome();
$output[] = $temp->toString();
}
}
}
return $output;
}
public static function rightCastleThroughCheck($input)
{
$alter = new ChessBoard();
$alter->copy($input);
$alter->changeTurn();
if ($input->whiteTurn()) {
$alter->set(5, 1, -1);
$alter->set(6, 1, ChessBoard::$WHITEKING);
} else {
$alter->set(5, 8, -1);
$alter->set(6, 8, ChessBoard::$BLACKKING);
}
return self::kingKillable("K,1,1," + $alter->toString());
}