public function ValidateFENStringStructureAndValues($FEN, &$errors)
{
$fields;
// Stores each field (space delimited item).
$row;
// Stores each row of the FEN.
$nWKingCount = 0;
$nBKingCount = 0;
// The number of kings found.
$errors = "";
if ($FEN == null) {
return false;
}
// Makes sure all groups and board ranks are available.
$fields = preg_split('/ /', $FEN);
if (count($fields) != 6) {
$errors = "The number of fields in the FEN is not 6.";
return false;
}
// If the board setup field ends with a "/" (PHPChess returned fen) then remove it.
if (STRING_UTILS::last_char($fields[0]) == "/") {
$fields[0] = substr($fields[0], 0, count($fields[0]) - 2);
}
$row = preg_split('/\\//', $fields[0]);
if (count($row) != 8) {
$errors = "The number of ranks in the board setup field is not 8.";
return false;
}
// Now check the values for each group are acceptable.
// First check that the board characters are acceptable.
for ($i = 0; $i < strlen($fields[0]); $i++) {
if (!($fields[0][$i] == 'K' || $fields[0][$i] == 'Q' || $fields[0][$i] == 'R' || $fields[0][$i] == 'B' || $fields[0][$i] == 'N' || $fields[0][$i] == 'P' || $fields[0][$i] == 'k' || $fields[0][$i] == 'q' || $fields[0][$i] == 'r' || $fields[0][$i] == 'b' || $fields[0][$i] == 'n' || $fields[0][$i] == 'p' || $fields[0][$i] == '/' || $fields[0][$i] == '1' || $fields[0][$i] == '2' || $fields[0][$i] == '3' || $fields[0][$i] == '4' || $fields[0][$i] == '5' || $fields[0][$i] == '6' || $fields[0][$i] == '7' || $fields[0][$i] == '8')) {
$errors = "The FEN string contains an invalid character: \n" + $fields[0][$i];
return false;
}
if ($fields[0][$i] == 'K') {
$nWKingCount++;
}
if ($fields[0][$i] == 'k') {
$nBKingCount++;
}
}
// Make sure there is one white and one black king
if ($nWKingCount == 0) {
$errors .= "No White king.\n";
}
if ($nBKingCount == 0) {
$errors .= "No Black king.\n";
}
if ($nWKingCount > 1) {
$errors .= "There can only be one king for black.\n";
}
if ($nBKingCount > 1) {
$errors .= "There can only be one king for black.\n";
}
// Check if the player turn is either w or b.
if (!($fields[1] == "w" || $fields[1] == "b")) {
$errors .= "Player turn must be either 'w' or 'b'.\n";
}
// Check the castling characters are valid. There must be 1 to 4 characters.
// If a '-' then no other character should be there. If no '-' then only k,K,q and Q allowed.
if (strlen($fields[2]) < 1 || strlen($fields[2]) > 4) {
$errors .= "The castling field of the FEN is invalid.\n";
}
if (strstr($fields[2], "-") && strlen($fields[2]) != 1) {
$errors .= "Cannot have a '-' in the castling field with other characters.\n";
}
if (strlen($fields[2]) > 1) {
for ($i = 0; $i < strlen($fields[2]); $i++) {
if (!($fields[2][$i] == 'k' || $fields[2][$i] == 'K' || $fields[2][$i] == 'Q' || $fields[2][$i] == 'q')) {
$errors .= "The castling field contained an invalid character.\n";
}
}
}
// The en-passant field can only be '-' or a valid tile (a1 through to h8)
if ($fields[3] != "-") {
if ($this->ConvertAlgebraicNotationTileToInteger($fields[3]) == -1) {
$errors .= "The en passant field must contain a valid tile reference.\n";
}
}
// The 50 move field must be non negative.
if ($this->IsStringNonNegativeNumber($fields[4]) == false) {
$errors .= "The 50 move (half move count) field must be non negative.\n";
}
// The full move number must be non negative.
if ($this->IsStringNonNegativeNumber($fields[5]) == false) {
$errors .= "The full move field must be non negative\n";
}
if ($errors == "") {
return true;
} else {
return false;
}
}
private function ConvertSANtoCoordinates($szMove, &$nStartTile, &$nEndTile, &$promotionType)
{
$nTmp;
if (strlen($szMove) < 2) {
return false;
}
//promotionType = PIECE_TYPE::UNDEFINED;
// If there is a p in the text then remove it since we don't need to be told the move was en passant
$nTmp = strpos($szMove, 'ep');
if ($nTmp !== FALSE) {
$szMove = substr($szMove, 0, $nTmp) . substr($szMove, $nTmp, strlen($szMove) - $nTmp - 2);
}
// Check if the move was check or checkmate and remove the last character
if (STRING_UTILS::last_char($szMove) == "+") {
//$szMove.Replace("+", "");
$szMove = substr($szMove, 0, strlen($szMove) - 1);
}
$nTmp = strpos($szMove, '#');
if ($nTmp !== FALSE) {
// Extract the move made which caused the checkmate. Note that crafty sends 0-1 {black mates} after the #.
//$szMove = $szMove.Substring(0, $szMove.Length - 1);
$szMove = substr($szMove, 0, $nTmp);
}
// Determine the type of the move (castle-, check+, mate#, promotion=)
if ($szMove == "O-O") {
if ($this->PlayerTurn == 0) {
$nStartTile = 4;
$nEndTile = 6;
} else {
$nStartTile = 60;
$nEndTile = 62;
}
return true;
} else {
if ($szMove == "O-O-O") {
if ($this->PlayerTurn == 0) {
$nStartTile = 4;
$nEndTile = 2;
} else {
$nStartTile = 60;
$nEndTile = 58;
}
return true;
} else {
if (strpos($szMove, '=') !== FALSE) {
// Get type to promote to
if (STRING_UTILS::last_char($szMove) == "N") {
$promotionType = PIECE_TYPE::KNIGHT;
} else {
if (STRING_UTILS::last_char($szMove) == "B") {
$promotionType = PIECE_TYPE::BISHOP;
} else {
if (STRING_UTILS::last_char($szMove) == "R") {
$promotionType = PIECE_TYPE::ROOK;
} else {
if (STRING_UTILS::last_char($szMove) == "Q") {
$promotionType = PIECE_TYPE::QUEEN;
}
}
}
}
// Get tiles
$szMove = substr($szMove, 0, strlen($szMove) - 2);
// Check if there is an x to indicate a piece was taken.
if ($szMove . Contains("x")) {
$nEndTile = $this->ChessUtils->ConvertAlgebraicNotationTileToInteger($szMove . Substring(2));
if ($this->PlayerTurn == 0) {
$nStartTile = $this->ChessUtils->ConvertAlgebraicNotationTileToInteger($szMove . Substring(0, 1) + "7");
} else {
$nStartTile = $this->ChessUtils->ConvertAlgebraicNotationTileToInteger($szMove . Substring(0, 1) + "2");
}
} else {
$nEndTile = $this->ChessUtils->ConvertAlgebraicNotationTileToInteger($szMove);
if ($this->PlayerTurn == 0) {
$nStartTile = $nEndTile - 8;
} else {
$nStartTile = $nEndTile + 8;
}
}
if ($nStartTile == -1 || $nEndTile == -1) {
return false;
}
return true;
} else {
if ($szMove[strlen($szMove) - 1] == 'Q' || $szMove[strlen($szMove) - 1] == 'B' || $szMove[strlen($szMove) - 1] == 'N' || $szMove[strlen($szMove) - 1] == 'R') {
// Get type to promote to
if ($szMove[strlen($szMove) - 1] == 'N') {
$promotionType = PIECE_TYPE::KNIGHT;
} else {
if ($szMove[strlen($szMove) - 1] == 'B') {
$promotionType = PIECE_TYPE::BISHOP;
} else {
if ($szMove[strlen($szMove) - 1] == 'R') {
$promotionType = PIECE_TYPE::ROOK;
} else {
if ($szMove[strlen($szMove) - 1] == 'Q') {
$promotionType = PIECE_TYPE::QUEEN;
}
}
}
}
// Remove the last char and then continue on finding the start and end tiles for this move.
$szMove = substr($szMove, 0, strlen($szMove) - 1);
// Make sure the move is valid for further processing.
if (strlen($szMove) < 2) {
return false;
}
}
}
}
}
// Last two chars indicate the end tile. Remove them from the string.
$nEndTile = $this->ChessUtils->ConvertAlgebraicNotationTileToInteger(substr(strlen($szMove) - 2));
if ($nEndTile == -1) {
return false;
}
$szMove = substr($szMove, 0, strlen($szMove) - 2);
// Check if a piece was taken and remove the x character if so.
if ($szMove[strlen($szMove) - 1] == 'x') {
$szMove = substr($szMove, 0, strlen($szMove) - 1);
}
// Check the remaining length.
if (strlen($szMove) == 0) {
if ($this->PlayerTurn == 0) {
//if (rgBoard[nEndTile / 8 - 1, nEndTile % 8] > 0) nStartTile = nEndTile - 8;
//else nStartTile = nEndTile - 16;
//return true;
// If the end tile is not rank 4 that means a pawn couldn't have moved two tiles
// up the rank.
if ($nEndTile / 8 != 3) {
// Check for a single move forward.
if ($this->Board[$this->floor[$nEndTile] - 1][$nEndTile % 8] == PIECE_TYPE::PAWN) {
$nStartTile = $nEndTile - 8;
} else {
if ($this->nEnPassantSquare == nEndTile) {
// Check if there is a white pawn to the left/right one rank down from the end tile
if ($nEndTile % 8 == 0) {
if ($this->Board[$this->floor[$nEndTile] - 1][$nEndTile % 8 + 1] == PIECE_TYPE::PAWN) {
$nStartTile = $nEndTile - 7;
} else {
return false;
}
} else {
if ($nEndTile % 8 > 0 && $nEndTile % 8 < 7) {
if ($this->Board[$this->floor[$nEndTile] - 1][$nEndTile % 8 - 1] == PIECE_TYPE::PAWN) {
$nStartTile = $nEndTile - 9;
} else {
if ($this->Board[$this->floor[$nEndTile] - 1][$nEndTile % 8 + 1] == PIECE_TYPE::PAWN) {
$nStartTile = $nEndTile - 7;
} else {
return false;
}
}
} else {
if ($this->Board[$this->floor[$nEndTile] - 1][$nEndTile % 8 - 1] == PIECE_TYPE::PAWN) {
$nStartTile = $nEndTile - 9;
} else {
return false;
}
}
}
}
}
} else {
// Check for a single move forward.
if ($this->Board[$this->floor[$nEndTile] - 1][$nEndTile % 8] == PIECE_TYPE::PAWN) {
$nStartTile = $nEndTile - 8;
} else {
if ($this->Board[$this->floor[$nEndTile] - 2][$nEndTile % 8] == PIECE_TYPE::PAWN) {
$nStartTile = $nEndTile - 16;
} else {
// Check if there is a black pawn to the left/right one rank up from the end tile
if ($nEndTile % 8 == 0) {
if ($this->Board[$this->floor[$nEndTile] + 1][$nEndTile % 8 + 1] == PIECE_TYPE::PAWN + 6) {
$nStartTile = $nEndTile + 9;
} else {
return false;
}
} else {
if ($nEndTile % 8 > 0 && $nEndTile % 8 < 7) {
if ($this->Board[$this->floor[$nEndTile] + 1][$nEndTile % 8 - 1] == PIECE_TYPE::PAWN + 6) {
$nStartTile = $nEndTile + 7;
} else {
if ($this->Board[$this->floor[$nEndTile] + 1][$nEndTile % 8 + 1] == PIECE_TYPE::PAWN + 6) {
$nStartTile = $nEndTile + 9;
} else {
return false;
}
}
} else {
if ($this->Board[$this->floor[$nEndTile] + 1][$nEndTile % 8 - 1] == PIECE_TYPE::PAWN + 6) {
$nStartTile = $nEndTile + 7;
} else {
return false;
}
}
}
}
}
}
} else {
//if ($this->Board[nEndTile / 8 + 1, nEndTile % 8] > 0) nStartTile = nEndTile + 8;
//else nStartTile = nEndTile + 16;
//return true;
// If the end tile is not rank 5 that means a pawn couldn't have moved two tiles
// down the rank.
if ($this->floor[$nEndTile] != 4) {
if ($this->Board[$this->floor[$nEndTile] + 1][$nEndTile % 8] == PIECE_TYPE::PAWN + 6) {
$nStartTile = $nEndTile + 8;
} else {
if ($this->nEnPassantSquare == $nEndTile) {
$nStartTile = -1;
return false;
}
}
} else {
if ($this->Board[$this->floor[$nEndTile] + 1][$nEndTile % 8] == PIECE_TYPE::PAWN + 6) {
$nStartTile = $nEndTile + 8;
} else {
if ($this->Board[$this->floor[$nEndTile] + 2][$nEndTile % 8] == PIECE_TYPE::PAWN + 6) {
$nStartTile = $nEndTile + 16;
} else {
$nStartTile = -1;
return false;
}
}
}
}
return true;
}
if (strlen($szMove) == 1) {
if ($szMove == 'a' || $szMove == 'b' || $szMove == 'c' || $szMove == 'd' || $szMove == 'e' || $szMove == 'f' || $szMove == 'g' || $szMove == 'h') {
if ($this->PlayerTurn == 0) {
$nTmp = $nEndTile / 8;
} else {
$nTmp = $this->floor[$nEndTile] + 2;
}
$nStartTile = $this->ChessUtils->ConvertAlgebraicNotationTileToInteger(substr($szMove, 0, 1) . $nTmp);
} else {
if ($szMove == 'K') {
$nStartTile = $this->ObtainAttackingTileForPieceType(PIECE_TYPE::KING, $nEndTile);
} else {
if ($szMove == 'Q') {
$nStartTile = $this->ObtainAttackingTileForPieceType(PIECE_TYPE::QUEEN, $nEndTile);
} else {
if ($szMove == 'R') {
$nStartTile = $this->ObtainAttackingTileForPieceType(PIECE_TYPE::ROOK, $nEndTile);
} else {
if ($szMove == 'B') {
$nStartTile = $this->ObtainAttackingTileForPieceType(PIECE_TYPE::BISHOP, $nEndTile);
} else {
if ($szMove == 'N') {
$nStartTile = $this->ObtainAttackingTileForPieceType(PIECE_TYPE::KNIGHT, $nEndTile);
}
}
}
}
}
}
if ($nStartTile == -1) {
return false;
}
return true;
}
if (strlen($szMove) == 2) {
// Find the piece type for the given file or rank
if ($szMove[0] == 'K') {
$nStartTile = $this->FindPieceLocatedInFileOrRank(PIECE_TYPE::KING, $szMove[1]);
} else {
if ($szMove[0] == 'Q') {
$nStartTile = $this->FindPieceLocatedInFileOrRank(PIECE_TYPE::QUEEN, $szMove[1]);
} else {
if ($szMove[0] == 'R') {
$nStartTile = $this->FindPieceLocatedInFileOrRank(PIECE_TYPE::ROOK, $szMove[1]);
} else {
if ($szMove[0] == 'B') {
$nStartTile = $this->FindPieceLocatedInFileOrRank(PIECE_TYPE::BISHOP, $szMove[1]);
} else {
if ($szMove[0] == 'N') {
$nStartTile = $this->FindPieceLocatedInFileOrRank(PIECE_TYPE::KNIGHT, $szMove[1]);
} else {
}
}
}
}
}
if ($nStartTile == -1) {
return false;
}
return true;
}
if (strlen($szMove) == 3) {
$nStartTile = $this->ChessUtils->ConvertAlgebraicNotationTileToInteger(substr($szMove, 1));
if ($nStartTile == -1) {
return false;
}
return true;
}
return false;
}
