public struct History {
	public typealias Array = [(
		SANMoveDescriptor.Value?, SANMoveDescriptor.Value?
	)]

	public enum SANMoveDescriptor {
		public typealias Value = String
		case pieceMove(from: Square, to: Square)
		case pawnPush(to: Square, promotion: Piece?)

		public var value: Value {
			return switch self {
			case .pieceMove(let from, let to):
				{
					guard let piece = from.piece else {
						return ""
					}
					#warning("Ugly ass code 🤢")
					var result =
						piece.kind == .Pawn
						? ""
						: "\(piece.kind.fenRepresentation(with: piece.color))"
					if let ambiguity = (to.targetted.first { $0 ~= piece }) {
						let file =
							ambiguity.position.file != from.position.file
							? Square.Position.File[from.position.file] : nil
						var rank: Int8? {
							if file == nil {
								return ambiguity.position.rank
									!= from.position.rank
									? from.position.rank : nil
							}
							return nil
						}
						if let f = file {
							result += f.rawValue
						} else if let r = rank {
							result += String(r)
						} else {
							result +=
								Square.Position.File[from.position.file]!
								.rawValue
								+ String(from.position.rank)
						}
					}
					if to.piece != nil {
						result += "x"
					}
					result +=
						"\(Square.Position.File[to.position.file]!.rawValue)\(String(to.position.rank))"
					return result
				}()
			case .pawnPush(let to, let promotion):
				""
			}
		}
	}

	public private(set) var values: Array = []

	internal mutating func add(_ san: SANMoveDescriptor) {
		#warning("To be tested")
		if let last = values.last {
			if last.1 == nil {
				values[values.count - 1].1 = san.value
				return
			}
		}
		values.append((san.value, nil))
	}
}