Crapette: add the foundation-priority stop rule and sequenced house moves

* cg-crapette.el (cg-crapette-stops): new defcustom.
(cg-crap--stop): call STOP (end your turn) or block, per the custom, when
you skip an available foundation play; wired into drop, draw, and end.
(cg-crap--builds-down-p, cg-crap--house-run, cg-crap--free-houses,
cg-crap--capacity, cg-crap--house-move, cg-crap--do-move): move a legal
sequence between houses, limited by the number of empty houses.
* test/card-games-tests.el: add cgt-crap-house-run, -sequence-move,
-sequence-space, -stop.
* NEWS: note the stop rule and sequenced moves.
This commit is contained in:
Corwin Brust 2026-07-01 03:25:50 -05:00
parent 0d8901041f
commit f7932047ce
3 changed files with 200 additions and 45 deletions

View file

@ -37,18 +37,28 @@
;;
;; On your turn you make as many legal moves as you like:
;; - move the top of your reserve, your waste, or any house onto a
;; foundation or a house, and
;; foundation or a house;
;; - move a whole SEQUENCE (a run built down in alternating colours)
;; from one house to another -- but only when there are enough empty
;; houses to have shifted it a card at a time; and
;; - LOAD a card from your reserve or waste onto the opponent's reserve
;; or waste when it is the same suit and one rank up or down.
;; A card that can go to a foundation MUST be played there before you turn
;; a card (foundation priority). When you can do no more, turn the top of
;; your hand: if it fits somewhere you keep going, otherwise it goes to
;; your waste and your turn ends.
;;
;; SIMPLIFICATIONS (documented; a faithful-but-streamlined first cut):
;; the adversarial "stop" call and its penalties are replaced by simply
;; enforcing foundation priority; sequenced group moves between houses are
;; done one card at a time; and the AI is a straightforward greedy player.
;; FOUNDATION PRIORITY and "STOP": a card that can go to a foundation must
;; be played there before anything else. If you build a house, load your
;; opponent, turn a card, or end your turn while a foundation play is
;; waiting, your opponent calls "STOP!" and your turn ends at once. The
;; piles that owe a foundation play are ringed in the hint colour. Set
;; `cg-crapette-stops' to nil for a gentler assist mode that blocks the
;; slip with a reminder instead of ending your turn.
;;
;; When you can do no more, turn the top of your hand: if it fits
;; somewhere you keep going, otherwise it goes to your waste and your turn
;; ends.
;;
;; SIMPLIFICATION (documented): the AI is a straightforward greedy player
;; and always observes foundation priority, so in practice only you can be
;; "stopped".
;;; Code:
@ -58,6 +68,14 @@
["A" "2" "3" "4" "5" "6" "7" "8" "9" "10" "J" "Q" "K"]
"Rank labels indexed 0 (Ace) .. 12 (King).")
(defcustom cg-crapette-stops t
"How Russian Bank enforces foundation priority on your turn.
When non-nil (the competitive rule), the opponent calls \"stop\" and you
forfeit the rest of your turn if you make any play other than an
available foundation move. When nil, such a slip is simply blocked with
a reminder and costs you nothing -- a gentler assist mode for learning."
:type 'boolean :group 'card-games)
(defclass cg-crapette-game (cg-game)
((vname :initform "Russian Bank"))
"Two-player Russian Bank (Crapette): you (South) versus one AI opponent.")
@ -126,7 +144,7 @@
(cg-put game :history nil)
(cg-put game :winner nil)
(cg-put game :message
"Your turn. Play to foundations first, then build the houses or load your opponent.")
"Your turn. Foundations first -- skip one and North calls STOP! Build the houses or load North.")
game))
@ -148,9 +166,13 @@
(let ((h (cg-crap--house game i)))
(if (null h)
t ; empty house takes anything
(let ((top (cg-crap--top h)))
(and (= (cdr card) (1- (cdr top)))
(not (eq (cg-crap--red-p card) (cg-crap--red-p top)))))))))
(cg-crap--builds-down-p (cg-crap--top h) card)))))
(defun cg-crap--builds-down-p (upper lower)
"Return non-nil when LOWER may sit on UPPER: one rank down, opposite colour."
(and upper lower
(= (cdr lower) (1- (cdr upper)))
(not (eq (cg-crap--red-p upper) (cg-crap--red-p lower)))))
(defun cg-crap--load-accepts (pile-top card)
"Return non-nil when CARD may be loaded onto a pile whose top is PILE-TOP.
@ -164,6 +186,66 @@ Loading needs the same suit and a rank one step up or down."
(cl-loop for i below 8 when (cg-crap--found-accepts game i card) return i))
;;;; Sequenced house moves
(defun cg-crap--house-run (game i)
"Return the movable top run of house I as a list, bottom-to-top.
The run is the longest sequence of cards at the top of the house that is
built down in alternating colours."
(let ((rev (reverse (cg-crap--house game i)))) ; top-first
(if (null rev) nil
(let ((run (list (car rev))) (prev (car rev)))
(catch 'done
(dolist (c (cdr rev)) ; each C sits below PREV
(if (cg-crap--builds-down-p c prev)
(progn (push c run) (setq prev c)) ; PREV builds down on C
(throw 'done nil))))
run))))
(defun cg-crap--free-houses (game)
"Return the number of empty houses in GAME."
(cl-count-if #'null (append (cg-get game :houses) nil)))
(defun cg-crap--capacity (game dest-i)
"Return how many cards may be moved as a group onto house DEST-I.
With F empty houses you may relay F+1 cards onto a non-empty house, or
F onto an empty house (the destination itself cannot serve as a relay)."
(let ((free (cg-crap--free-houses game)))
(if (cg-crap--house game dest-i) (1+ free) free)))
(defun cg-crap--house-move (game i j)
"Move a legal sequence from house I onto house J in GAME.
Return non-nil on success, the symbol `space' when the sequence is legal
but there are too few empty houses, and nil when nothing fits."
(if (= i j)
nil
(let* ((run (cg-crap--house-run game i))
(rlen (length run))
(dst (cg-crap--house game j))
(dsttop (cg-crap--top dst))
(cap (cg-crap--capacity game j))
(n nil))
(when (> rlen 0)
(if (null dsttop)
(setq n (min rlen (max cap 0))) ; empty house: as many as fit
(cl-loop for k from 0 below rlen ; RUN is bottom-to-top
for card = (nth k run)
when (cg-crap--builds-down-p dsttop card)
do (setq n (- rlen k)) (cl-return)))
(cond
((or (null n) (< n 1)) nil)
((> n cap) 'space)
(t
(cg-crap--snapshot game)
(let* ((pile (cg-crap--house game i))
(keep (butlast pile n))
(moved (last pile n)))
(aset (cg-get game :houses) i keep)
(aset (cg-get game :houses) j (append dst moved)))
(cg-put game :moves (1+ (cg-get game :moves)))
t))))))
;;;; Spots (the cursor visits piles)
(defun cg-crap--spots (_game)
@ -256,6 +338,16 @@ Return non-nil when the move was legal and performed."
(cg-put game :moves (1+ (cg-get game :moves)))
t)))
(defun cg-crap--do-move (game from to p)
"Perform player P's move from FROM to TO in GAME.
A house-to-house move may carry a legal sequence of cards (see
`cg-crap--house-move'); every other move carries a single card. Returns
the same values as those functions (non-nil on success, `space' when a
sequence is too long for the empty houses)."
(if (and (eq (car from) 'house) (eq (car to) 'house))
(cg-crap--house-move game (cdr from) (cdr to))
(cg-crap--move game from to p)))
;;;; Turn logic
@ -305,6 +397,19 @@ Return non-nil when the move was legal and performed."
(cg-put game :turn 0)
(cg-put game :history nil))))
(defun cg-crap--stop (game)
"Enforce foundation priority: call \"stop\" or block, per `cg-crapette-stops'.
Return non-nil when the offending action must be abandoned by its caller."
(when (cg-crap--forced game 0)
(if cg-crapette-stops
(let ((note "North calls STOP -- you must play to a foundation first!"))
(message "%s" note)
(cg-put game :sel nil)
(cg-crap--end-turn game)
(cg-put game :message (concat note " " (cg-get game :message))))
(cg-crap--msg game "Play to a foundation first (press f on a highlighted pile)."))
t))
;;;; The AI opponent (player 1)
@ -416,7 +521,7 @@ is guaranteed to end."
(erase-buffer)
(insert (cg-crap--render g))
(cg-insert-legend
"arrows move · RET pick up/drop · f foundation · SPC turn a card · e end turn · u undo · n new · q menu")
"arrows move · RET pick up/drop (runs move house→house) · f foundation · SPC turn a card · e end · u undo · n new · q menu")
(goto-char (point-min))))
@ -448,13 +553,24 @@ is guaranteed to end."
(spot (nth (cg-get g :cursor) spots)) (sel (cg-get g :sel)))
(when (cg-crap--your-turn-p g)
(if sel
(if (cg-crap--move g sel spot 0)
(progn (cg-put g :sel nil) (cg-crap--after-human-move g))
(cg-crap--msg g "That card can't go there."))
(unless (and (not (eq (car spot) 'found)) (cg-crap--stop g))
(let ((res (cg-crap--do-move g sel spot 0)))
(cond
((eq res 'space)
(cg-crap--msg g "Not enough empty houses to move that whole sequence."))
(res (cg-put g :sel nil) (cg-crap--after-human-move g))
(t (cg-crap--msg g "That card can't go there.")))))
(if (and (cg-crap--source-p spot 0) (cg-crap--spot-top g spot))
(progn (cg-put g :sel spot)
(cg-crap--msg g (format "Picked up %s -- choose where to drop it."
(cg-crap--card-string (cg-crap--spot-top g spot)))))
(let* ((top (cg-crap--spot-top g spot))
(run (and (eq (car spot) 'house) (cg-crap--house-run g (cdr spot))))
(n (length run)))
(cg-put g :sel spot)
(cg-crap--msg g
(if (> n 1)
(format "Picked up a run of %d (%s on top) -- drop it on a house."
n (cg-crap--card-string top))
(format "Picked up %s -- choose where to drop it."
(cg-crap--card-string top)))))
(cg-crap--msg g "Nothing of yours to pick up there."))))
(cg-crap--redisplay)))
@ -478,24 +594,21 @@ If it fits nowhere your turn ends."
(interactive)
(let ((g cg-crap--game))
(when (cg-crap--your-turn-p g)
(cond
((cg-crap--forced g 0)
(cg-crap--msg g "Play to a foundation first (press f on a highlighted pile)."))
((null (cg-crap--hand g 0))
(cg-crap--msg g "Your hand is empty -- press e to end your turn."))
(t
(cg-crap--snapshot g)
(let* ((hand (cg-crap--hand g 0)) (card (cg-crap--top hand)))
(aset (cg-get g :hand) 0 (butlast hand 1))
(aset (cg-get g :waste) 0 (append (cg-crap--waste g 0) (list card)))
(cg-put g :sel nil)
(if (cg-crap--card-playable g 0 card)
(cg-crap--msg g (format "Turned %s onto your waste -- play on."
(cg-crap--card-string card)))
(progn
(cg-crap--msg g (format "Turned %s -- nothing to do, your turn ends."
(cg-crap--card-string card)))
(cg-crap--end-turn g)))))))
(unless (cg-crap--stop g)
(if (null (cg-crap--hand g 0))
(cg-crap--msg g "Your hand is empty -- press e to end your turn.")
(cg-crap--snapshot g)
(let* ((hand (cg-crap--hand g 0)) (card (cg-crap--top hand)))
(aset (cg-get g :hand) 0 (butlast hand 1))
(aset (cg-get g :waste) 0 (append (cg-crap--waste g 0) (list card)))
(cg-put g :sel nil)
(if (cg-crap--card-playable g 0 card)
(cg-crap--msg g (format "Turned %s onto your waste -- play on."
(cg-crap--card-string card)))
(progn
(cg-crap--msg g (format "Turned %s -- nothing to do, your turn ends."
(cg-crap--card-string card)))
(cg-crap--end-turn g)))))))
(cg-crap--redisplay)))
(defun cg-crap-end ()
@ -503,10 +616,9 @@ If it fits nowhere your turn ends."
(interactive)
(let ((g cg-crap--game))
(when (cg-crap--your-turn-p g)
(if (cg-crap--forced g 0)
(cg-crap--msg g "Play to a foundation first (press f on a highlighted pile).")
(progn (cg-crap--msg g "You end your turn.")
(cg-crap--end-turn g))))
(unless (cg-crap--stop g)
(cg-crap--msg g "You end your turn.")
(cg-crap--end-turn g)))
(cg-crap--redisplay)))
(defun cg-crap-undo ()
@ -535,7 +647,7 @@ If it fits nowhere your turn ends."
"Describe the controls."
(interactive)
(message
"Arrows: move RET: pick up/drop f: to foundation SPC: turn a card e: end turn u: undo n: new q: menu"))
"Arrows: move RET: pick up/drop (runs move house->house) f: to foundation SPC: turn a card e: end turn u: undo n: new q: menu"))
(defvar cg-crapette-mode-map
(let ((map (make-sparse-keymap)))