Files
NowChessSystems/modules/rule/src/main/scala/de/nowchess/rules/RuleSet.scala
T
2026-04-04 17:11:11 +02:00

40 lines
1.5 KiB
Scala

package de.nowchess.rules
import de.nowchess.api.game.GameContext
import de.nowchess.api.board.Square
import de.nowchess.api.move.Move
/** Extension point for chess rule variants (standard, Chess960, etc.).
* All rule queries are stateless: given a GameContext, return the answer.
*/
trait RuleSet:
/** All pseudo-legal moves for the piece on `square` (ignores check). */
def candidateMoves(context: GameContext, square: Square): List[Move]
/** Legal moves for `square`: candidates that don't leave own king in check. */
def legalMoves(context: GameContext, square: Square): List[Move]
/** All legal moves for the side to move. */
def allLegalMoves(context: GameContext): List[Move]
/** True if the side to move's king is in check. */
def isCheck(context: GameContext): Boolean
/** True if the side to move is in check and has no legal moves. */
def isCheckmate(context: GameContext): Boolean
/** True if the side to move is not in check and has no legal moves. */
def isStalemate(context: GameContext): Boolean
/** True if neither side has enough material to checkmate. */
def isInsufficientMaterial(context: GameContext): Boolean
/** True if halfMoveClock >= 100 (50-move rule). */
def isFiftyMoveRule(context: GameContext): Boolean
/** Apply a legal move to produce the next game context.
* Handles all special move types: castling, en passant, promotion.
* Updates castling rights, en passant square, half-move clock, turn, and move history.
*/
def applyMove(context: GameContext, move: Move): GameContext