Can now move pieces

Sources/Engine/Board.swift

@@ -4,7 +4,7 @@ enum Event {
 }
 protocol EventDelegate {
 	func notify(_ event: Event)
-	func movePiece(_ piece: Piece, to dst: Square.Position)
+	func movePiece(_ piece: Piece, to dst: Square.Position) throws
 }
 public class Board: CustomStringConvertible, EventDelegate {
 	public typealias Grid = [[Square]]
@@ -24,8 +24,87 @@ public class Board: CustomStringConvertible, EventDelegate {
 
 	}
 
-	func movePiece(_ piece: Piece, to dst: Square.Position) {
+	func movePiece(_ piece: Piece, to dst: Square.Position) throws {
+		let from = piece.position
+		piece.position = dst
+		squares[dst.index!].piece = piece
+		squares[from.index!].piece = nil
+		fen.set(from: board, castling: .All, enPassant: fen.enPassant)
+	}
 
+	public enum MoveFailure: Error, CustomStringConvertible {
+		case sourceSquareUnreachable(pos: Square.Position)
+		case destinationSquareUnreachable(pos: Square.Position)
+		case squareHasNoPiece(pos: Square.Position)
+		case destinationIsIllegal(pos: Square.Position)
+		case squareANIsTooLong(an: String)
+		case squareANIsTooShort(an: String)
+
+		public var description: String {
+			return switch self {
+			case .sourceSquareUnreachable(let pos):
+				"The source square given \(pos.rank) \(pos.file) is unreachable."
+			case .destinationSquareUnreachable(let pos):
+				"The destination square given \(pos.rank) \(pos.file) is unreachable."
+			case .squareHasNoPiece(let pos):
+				"The square \(pos.rank) \(pos.file) doesn't have any piece to be moved."
+			case .destinationIsIllegal(let pos):
+				"The destination square given \(pos.rank) \(pos.file) is illegal to be moved to."
+			case .squareANIsTooLong(let an):
+				"The algebraic notation \(an) is too long. (Needs to be 2 characters)"
+			case .squareANIsTooShort(let an):
+				"The algebraic notation \(an) is too short. (Needs to be 2 characters)"
+			}
+		}
+	}
+
+	public func move(src: String, dst: String) throws {
+		guard src.count < 3 else {
+			throw MoveFailure.squareANIsTooLong(an: src)
+		}
+		guard src.count > 1 else {
+			throw MoveFailure.squareANIsTooShort(an: src)
+		}
+		guard dst.count < 3 else {
+			throw MoveFailure.squareANIsTooLong(an: dst)
+		}
+		guard dst.count > 1 else {
+			throw MoveFailure.squareANIsTooShort(an: dst)
+		}
+		guard let f1 = src.first, let r1 = src.last, r1.isWholeNumber else {
+			return
+		}
+		guard let f2 = dst.first, let r2 = src.last, r2.isWholeNumber else {
+			return
+		}
+		guard
+			let srcFile = Square.Position.File.init(rawValue: String(f1))?.value
+		else {
+			return
+		}
+		guard
+			let dstFile = Square.Position.File.init(rawValue: String(f2))?.value
+		else {
+			return
+		}
+
+		try move(
+			src: Square.Position(rank: Int8(String(r1))!, file: srcFile),
+			dst: Square.Position(rank: Int8(String(r2))!, file: dstFile))
+	}
+
+	public func move(src: Square.Position, dst: Square.Position) throws {
+		guard let srcSquare = self[src] else {
+			throw MoveFailure.sourceSquareUnreachable(pos: src)
+		}
+		guard self[dst] != nil else {
+			throw MoveFailure.destinationSquareUnreachable(pos: src)
+		}
+		guard let piece = srcSquare.piece else {
+			throw MoveFailure.squareHasNoPiece(pos: src)
+		}
+
+		try piece.move(to: dst)
 	}
 
 	public func getSquareInfo(on pos: Square.Position) -> Square? {

Sources/Engine/FEN.swift

@@ -64,7 +64,7 @@ public struct Fen: CustomStringConvertible {
 	}
 
 	internal mutating func set(
-		from board: Board.Grid, castiling ca: CastlingAvailibility,
+		from board: Board.Grid, castling ca: CastlingAvailibility,
 		enPassant: String
 	) {
 		#warning(

Sources/Engine/Pieces/Bishop.swift

@@ -12,20 +12,8 @@ final class Bishop: Piece, DiagonalMoves {
 		return pseudoLegalPositions.filter { isLegal(on: $0) }
 	}
 
-	override func move(to dst: Square.Position) {
-	}
-
 	override func isLegal(on pos: Square.Position) -> Bool {
-		if let board = board, let s = board[pos] {
+		super.isLegal(on: pos)
-			if let p = s.piece {
-				if p.color == color { return false }
-				if p.kind == .King {
-					delegate?.notify(.kingInCheck(self))
-					return false
-				}
-			}
-		}
-		return true
 	}
 
 	init(with color: Color, on position: Square.Position) {

Sources/Engine/Pieces/King.swift

@@ -21,21 +21,8 @@ final class King: Piece {
 		return pseudoLegalPositions.filter { isLegal(on: $0) }
 	}
 
-	override func move(to dst: Square.Position) {
-	}
-
 	override func isLegal(on pos: Square.Position) -> Bool {
-		if let board = board, let s = board[pos] {
+		super.isLegal(on: pos)
-			if let p = s.piece {
-				if p.color == color { return false }
-				if p.kind == .King {
-					// TODO: Notify board of check
-					return false
-				}
-			}
-
-		}
-		return true
 	}
 
 	init(with color: Color, on position: Square.Position) {

Sources/Engine/Pieces/Knight.swift

@@ -20,22 +20,8 @@ final class Knight: Piece {
 		return pseudoLegalPositions.filter { isLegal(on: $0) }
 	}
 
-	override func move(to dst: Square.Position) {
-	}
-
 	override func isLegal(on pos: Square.Position) -> Bool {
-		if let board = board, let s = board[pos] {
+		super.isLegal(on: pos)
-			if let p = s.piece {
-				if p.color == color { return false }
-				if p.kind == .King {
-					// TODO: Notify board of check
-					delegate?.notify(.kingInCheck(self))
-					return false
-				}
-			}
-
-		}
-		return true
 	}
 
 	init(with color: Color, on position: Square.Position) {

Sources/Engine/Pieces/Pawn.swift

@@ -17,37 +17,8 @@ final class Pawn: Piece {
 		color == .Black ? "♟" : "♙"
 	}
 
-	override func move(to dst: Square.Position) {
-		if !(legalPositions.contains { $0 == dst }) {
-			return
-		}
-
-		delegate?.movePiece(self, to: dst)
-
-		// if let board = board, var s = board[position], var d = board[dst] {
-		// 	s.piece = self
-		// 	d.piece = nil
-		// }
-
-		// position = dst
-
-		// return true
-	}
-
 	override func isLegal(on pos: Square.Position) -> Bool {
-		// TODO: Handle "En-Passant"
+		super.isLegal(on: pos)
-		if let board = board, let s = board[pos] {
-			if let p = s.piece {
-				if p.color == color { return false }
-				if p.kind == .King {
-					// TODO: Notify board of check
-					delegate?.notify(.kingInCheck(self))
-					return false
-				}
-			}
-
-		}
-		return true
 	}
 
 	init(with color: Color, on position: Square.Position) {

Sources/Engine/Pieces/Piece.swift

@@ -69,8 +69,28 @@ public class Piece {
 		return []
 	}
 	internal var delegate: EventDelegate?
-	internal func move(to dst: Square.Position) {}
+	internal func move(to dst: Square.Position) throws {
-	internal func isLegal(on pos: Square.Position) -> Bool { false }
+		if !(legalPositions.contains { $0 == dst }) {
+			throw Board.MoveFailure.destinationIsIllegal(pos: dst)
+		}
+
+		try delegate?.movePiece(self, to: dst)
+	}
+	internal func isLegal(on pos: Square.Position) -> Bool {
+
+		if let board = board, let s = board[pos] {
+			if let p = s.piece {
+				if p.color == color { return false }
+				if p.kind == .King {
+					// TODO: Notify board of check
+					delegate?.notify(.kingInCheck(self))
+					return false
+				}
+			}
+
+		}
+		return true
+	}
 
 	internal init(kind: Kind, on pos: Square.Position, with col: Color) {
 		self.kind = kind

Sources/Engine/Pieces/Queen.swift

@@ -11,23 +11,8 @@ final class Queen: Piece, LinearMoves, DiagonalMoves {
 		return pseudoLegalPositions.filter { isLegal(on: $0) }
 	}
 
-	override func move(to dst: Square.Position) {
-
-	}
-
 	override func isLegal(on pos: Square.Position) -> Bool {
-		if let board = board, let s = board[pos] {
+		super.isLegal(on: pos)
-			if let p = s.piece {
-				if p.color == color { return false }
-				if p.kind == .King {
-					// TODO: Notify board of check
-					delegate?.notify(.kingInCheck(self))
-					return false
-				}
-			}
-
-		}
-		return true
 	}
 
 	init(with color: Color, on position: Square.Position) {

Sources/Engine/Pieces/Rook.swift

@@ -12,22 +12,8 @@ final class Rook: Piece, LinearMoves {
 		return pseudoLegalPositions.filter { isLegal(on: $0) }
 	}
 
-	override func move(to dst: Square.Position) {
-	}
-
 	override func isLegal(on pos: Square.Position) -> Bool {
-		if let board = board, let s = board[pos] {
+		super.isLegal(on: pos)
-			if let p = s.piece {
-				if p.color == color { return false }
-				if p.kind == .King {
-					// TODO: Notify board of check
-					delegate?.notify(.kingInCheck(self))
-					return false
-				}
-			}
-
-		}
-		return true
 	}
 
 	init(with color: Color, on position: Square.Position) {

Sources/exe/main.swift

@@ -11,4 +11,18 @@ print(board)
 
 // }
 
+do {
+	try board.move(src: "e4", dst: "f6")
+} catch {
+	print(error)
+}
+do {
+	try board.move(src: .init(rank: 2, file: 5), dst: .init(rank: 4, file: 5))
+} catch {
+	print(error)
+}
+
+print(board)
+print(board.fen)
+
 // let square = board.getSquareInfo(on: .init(rank: 2, file: 7))

Tests/EngineTests/EngineTests.swift

@@ -109,7 +109,7 @@ final class EngineTests: XCTestCase {
 		let board: Board = .init()
 		let fen = board.fen.value
 		board.fen.set(
-			from: board.board, castiling: board.fen.castlingAvailibility,
+			from: board.board, castling: board.fen.castlingAvailibility,
 			enPassant: board.fen.enPassant)
 		XCTAssertEqual(
 			fen, board.fen.value, "Expected \(fen) got \(board.fen.value)")