Pawn moves

Sources/Engine/Pieces/Bishop.swift

@@ -26,7 +26,13 @@ final class Bishop: Piece, DiagonalMoves {
 					let piece = square.piece
 				{
 					if piece.color != color {
-						delegate?.notify(.piecePinned(from: self, on: piece))
+						if let king = piece as? King {
+							delegate?.notify(.kingInCheck(self, on: king))
+							legalPositions.removeLast()
+						} else {
+							delegate?.notify(
+								.piecePinned(from: self, on: piece))
+						}
 						last = position
 					}
 				}
@@ -35,7 +41,12 @@ final class Bishop: Piece, DiagonalMoves {
 	}
 
 	override func isLegal(on pos: Square.Position) -> Bool {
-		super.isLegal(on: pos)
+		if let s = delegate?.getSquareInfo(on: pos), let p = s.piece,
+			p.color == color
+		{
+			return false
+		}
+		return true
 	}
 
 	init(with color: Color, on position: Square.Position) {

Sources/Engine/Pieces/Pawn.swift

@@ -1,6 +1,8 @@
 final class Pawn: Piece {
+	private var sign: Int8 {
+		color == .Black ? -1 : 1
+	}
 	override var pseudoLegalPositions: [Square.Position] {
-		let sign: Int8 = color == .Black ? -1 : 1
 		return [
 			position + (1 * sign, 0),
 			position + (2 * sign, 0),
@@ -14,7 +16,25 @@ final class Pawn: Piece {
 	}
 
 	override func isLegal(on pos: Square.Position) -> Bool {
-		super.isLegal(on: pos)
+		#warning("Handle en-passant")
+		if pos == position + (2 * sign, 0) && halfMoveCount > 0 {
+			return false
+		}
+		if (pos == position + (1 * sign, 0) || pos == position + (2 * sign, 0))
+			&& delegate?.getSquareInfo(on: pos)?.piece != nil
+		{
+			return false
+		}
+		guard super.isLegal(on: pos) else {
+			return false
+		}
+		if (pos == position + (1 * sign, 1) || pos == position + (1 * sign, -1))
+			&& delegate?.getSquareInfo(on: pos)?.piece == nil
+		{
+			return false
+		}
+
+		return true
 	}
 
 	init(with color: Color, on position: Square.Position) {

Sources/Engine/Pieces/Piece.swift

@@ -85,7 +85,6 @@ public class Piece: Hashable {
 			if let p = s.piece {
 				if p.color == color { return false }
 				if let king = p as? King {
-					#warning("It could be in check or behind another piece.")
 					delegate?.notify(.kingInCheck(self, on: king))
 					return false
 				}

Sources/Engine/Pieces/Queen.swift

@@ -28,7 +28,13 @@ final class Queen: Piece, LinearMoves, DiagonalMoves {
 					let piece = square.piece
 				{
 					if piece.color != color {
-						delegate?.notify(.piecePinned(from: self, on: piece))
+						if let king = piece as? King {
+							delegate?.notify(.kingInCheck(self, on: king))
+							legalPositions.removeLast()
+						} else {
+							delegate?.notify(
+								.piecePinned(from: self, on: piece))
+						}
 						last = position
 					}
 				}
@@ -37,7 +43,12 @@ final class Queen: Piece, LinearMoves, DiagonalMoves {
 	}
 
 	override func isLegal(on pos: Square.Position) -> Bool {
-		super.isLegal(on: pos)
+		if let s = delegate?.getSquareInfo(on: pos), let p = s.piece,
+			p.color == color
+		{
+			return false
+		}
+		return true
 	}
 
 	init(with color: Color, on position: Square.Position) {

Sources/Engine/Pieces/Rook.swift

@@ -26,7 +26,13 @@ final class Rook: Piece, LinearMoves {
 					let piece = square.piece
 				{
 					if piece.color != color {
-						delegate?.notify(.piecePinned(from: self, on: piece))
+						if let king = piece as? King {
+							delegate?.notify(.kingInCheck(self, on: king))
+							legalPositions.removeLast()
+						} else {
+							delegate?.notify(
+								.piecePinned(from: self, on: piece))
+						}
 						last = position
 					}
 				}
@@ -35,7 +41,12 @@ final class Rook: Piece, LinearMoves {
 	}
 
 	override func isLegal(on pos: Square.Position) -> Bool {
-		super.isLegal(on: pos)
+		if let s = delegate?.getSquareInfo(on: pos), let p = s.piece,
+			p.color == color
+		{
+			return false
+		}
+		return true
 	}
 
 	init(with color: Color, on position: Square.Position) {