Files
swift-chess/Sources/Engine/Pieces/CommonMoves.swift

119 lines
2.3 KiB
Swift

private func getDirectionalMoves(
from pos: Square.Position, with dir: [(Int8, Int8)]
) -> [Square.Position] {
var squares = [Square.Position]()
for i: (Int8, Int8) in dir {
var currentSquare = pos + i
while currentSquare.index != nil {
squares.append(currentSquare)
currentSquare += i
}
}
return squares
}
protocol DiagonalMoves {
func getDiagonalMoves(from pos: Square.Position) -> [Square.Position]
}
protocol Direction: CaseIterable {
var values: (Int8, Int8) { get }
static func isLegal(
last: inout Square.Position?,
current: Square.Position
) -> Bool
}
public enum DiagonalDirection: Direction {
case northWest
case northEast
case southEast
case southWest
public var values: (Int8, Int8) {
return switch self {
case .northWest: (1, -1)
case .northEast: (1, 1)
case .southEast: (-1, 1)
case .southWest: (-1, -1)
}
}
public static func isLegal(
last: inout Square.Position?,
current:
Square.Position
) -> Bool {
var isPred = false
for dir in DiagonalDirection.allCases {
isPred = last == current - dir.values
if isPred {
last = current
break
}
}
return isPred
}
}
extension DiagonalMoves {
func getDiagonalMoves(from pos: Square.Position) -> [Square.Position] {
getDirectionalMoves(
from: pos,
with: [
DiagonalDirection.northWest.values,
DiagonalDirection.northEast.values,
DiagonalDirection.southEast.values,
DiagonalDirection.southWest.values,
])
}
}
protocol LinearMoves {
func getLinearMoves(from pos: Square.Position) -> [Square.Position]
}
public enum LinearDirection: Direction {
case north
case south
case east
case west
public var values: (Int8, Int8) {
return switch self {
case .north: (1, 0)
case .south: (-1, 0)
case .east: (0, 1)
case .west: (0, -1)
}
}
public static func isLegal(
last: inout Square.Position?, current: Square.Position
) -> Bool {
var isPred = false
for dir in LinearDirection.allCases {
isPred = last == current - dir.values
if isPred {
last = current
break
}
}
return isPred
}
}
extension LinearMoves {
func getLinearMoves(from pos: Square.Position) -> [Square.Position] {
getDirectionalMoves(
from: pos,
with: [
LinearDirection.north.values,
LinearDirection.east.values,
LinearDirection.south.values,
LinearDirection.west.values,
])
}
}