card-game.el/cg-bridge.el
Corwin Brust 09adcaa3ea Add Contract Bridge: auction, dummy play, and rubber scoring
New cg-bridge.el: a four-handed Bridge game (you are South, partnering
North against East and West) on the shared cg-game base.

* Auction: level/strain bids plus pass, double, and redouble, with the
  three-pass end rule, pass-outs, doubling state, and declarer
  determination (first of the side to name the strain).
* Play: follow-suit with the dummy exposed after the opening lead; the
  declarer plays both hands. Trick resolution honours trump and no-trump.
* Scoring: classic rubber -- trick points below the line toward game;
  overtricks, slam, insult, and undertrick penalties above; vulnerability
  and the rubber bonus. Verified against known results.
* A small natural bidding AI (openings, NT, raises with a fit, simple
  overcalls) that always terminates the auction, plus a greedy
  card-play AI.

Wire cg-bridge into the chooser, the Makefile, and the README, and add
two ERT tests (scoring math and a dozen full AI-driven deals). The suite
is now 109/109 and every file byte-compiles cleanly.
2026-06-25 06:53:51 -05:00

730 lines
31 KiB
EmacsLisp

;;; cg-bridge.el --- Contract Bridge with rubber scoring -*- lexical-binding: t; -*-
;; Copyright (C) 2026 Corwin Brust
;; Author: Corwin Brust <corwin@bru.st>
;; Maintainer: Corwin Brust <corwin@bru.st>
;; Version: 1.0.60
;; Package-Requires: ((emacs "26.1"))
;; Keywords: games
;; URL: https://code.bru.st/corwin/card-game.el
;; This program is free software; you can redistribute it and/or modify
;; it under the terms of the GNU General Public License as published by
;; the Free Software Foundation, either version 3 of the License, or
;; (at your option) any later version.
;; This program is distributed in the hope that it will be useful,
;; but WITHOUT ANY WARRANTY; without even the implied warranty of
;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
;; GNU General Public License for more details.
;; You should have received a copy of the GNU General Public License
;; along with this program. If not, see <https://www.gnu.org/licenses/>.
;;; Commentary:
;; Contract Bridge: you are South, partnered with North, against East and
;; West. Each deal has an auction -- bids of a level (1-7) and a strain
;; (clubs, diamonds, hearts, spades, or no-trump), plus Pass, Double, and
;; Redouble -- followed by the play of thirteen tricks with the dummy (the
;; declarer's partner) exposed. Scoring is the classic rubber game: trick
;; points below the line race toward game, and bonuses, overtricks, and
;; penalties go above; two games win the rubber.
;;
;; When you are declarer you play both your own hand and the dummy; when
;; you defend you play your own cards and the computer plays the rest.
;;
;; The bidding AI is a deliberately small natural system (it opens on
;; about twelve points, raises to game with a fit, and overcalls a good
;; long suit); it reaches sensible contracts but is no expert. Cards use
;; the package cons (SUIT . RANK), SUIT 0 spades, 1 clubs, 2 diamonds,
;; 3 hearts, RANK 0 (Two) .. 12 (Ace).
;;; Code:
(require 'cl-lib)
(require 'eieio)
(require 'cg-core)
(defconst cg-bridge-ranks
["2" "3" "4" "5" "6" "7" "8" "9" "10" "J" "Q" "K" "A"]
"Rank labels indexed 0 (Two) .. 12 (Ace).")
(defconst cg-bridge-strains ["" "" "" "" "NT"]
"Strain glyphs indexed 0 clubs, 1 diamonds, 2 hearts, 3 spades, 4 no-trump.")
(defconst cg-bridge--strain-suit [1 2 3 0 nil]
"Map a strain index to its trump suit index (nil for no-trump).")
(defconst cg-bridge--suit-strain [3 0 1 2]
"Map a suit index (0 S,1 C,2 D,3 H) to its strain index.")
(defconst cg-bridge-seat-names ["South" "West" "North" "East"]
"Seat names indexed 0..3 clockwise from the human.")
(defclass cg-bridge-game (cg-game)
((vname :initform "Bridge"))
"A game of contract Bridge.")
(defun cg-bridge-card-string (card)
"Return a short string for CARD."
(if (null card) "·"
(concat (aref cg-bridge-ranks (cdr card)) (cg-suit-glyph (car card)))))
(defun cg-bridge--sort (cards)
"Return CARDS sorted by suit then rank (high first) for display."
(sort (copy-sequence cards)
(lambda (a b) (if (= (car a) (car b)) (> (cdr a) (cdr b)) (< (car a) (car b))))))
(defun cg-bridge--deck ()
"Return a fresh shuffled 52-card deck."
(random t)
(cg-shuffle (cl-loop for s below 4 append
(cl-loop for r below 13 collect (cons s r)))))
;;;; Hand evaluation
(defun cg-bridge--hcp (hand)
"Return the high-card points of HAND (A=4 K=3 Q=2 J=1)."
(let ((p 0))
(dolist (c hand p)
(setq p (+ p (pcase (cdr c) (12 4) (11 3) (10 2) (9 1) (_ 0)))))))
(defun cg-bridge--suit-len (hand suit)
"Return how many cards of SUIT are in HAND."
(cl-count suit hand :key #'car))
(defun cg-bridge--longest (hand)
"Return the suit index HAND holds most of (ties prefer majors, then spades)."
(let ((best 0) (bestn -1))
;; check in order hearts, diamonds, clubs, spades so spades win ties last
(dolist (s '(3 2 1 0))
(let ((n (cg-bridge--suit-len hand s)))
(when (>= n bestn) (setq bestn n best s))))
best))
(defun cg-bridge--balanced-p (hand)
"Return non-nil when HAND has a balanced shape (no void/singleton)."
(let ((doubletons 0) (ok t))
(dotimes (s 4)
(let ((n (cg-bridge--suit-len hand s)))
(when (< n 2) (setq ok nil))
(when (= n 2) (setq doubletons (1+ doubletons)))))
(and ok (<= doubletons 1))))
;;;; Auction mechanics
(defsubst cg-bridge--hand (game s) (aref (cg-get game :hands) s))
(defsubst cg-bridge--set-hand (game s v) (aset (cg-get game :hands) s v))
(defsubst cg-bridge--side (s) (mod s 2))
(cl-defmethod cg-bridge--deal ((game cg-bridge-game))
"Deal a fresh Bridge hand into GAME, leaving it ready for the auction."
(let ((deck (cg-bridge--deck)) (hands (make-vector 4 nil)))
(dotimes (s 4)
(aset hands s (cg-bridge--sort (cl-loop repeat 13 collect (pop deck)))))
(cg-put game :hands hands)
(cg-put game :calls nil) ; list of (SEAT . CALL), newest first
(cg-put game :contract nil) ; (LEVEL . STRAIN)
(cg-put game :declarer nil)
(cg-put game :doubled 0)
(cg-put game :dealer (or (cg-get game :dealer) 0))
(cg-put game :bidder (cg-get game :dealer))
(cg-put game :phase 'auction)
(cg-put game :cursor 0)
(cg-put game :bid-level 1) ; UI: level being composed
(cg-put game :bid-strain 0)
(cg-put game :trick nil)
(cg-put game :tricks 0) ; declarer-side tricks won
(cg-put game :dummy nil)
(cg-put game :exposed nil)
(unless (cg-get game :below) (cg-put game :below (make-vector 2 0)))
(unless (cg-get game :above) (cg-put game :above (make-vector 2 0)))
(unless (cg-get game :games) (cg-put game :games (make-vector 2 0)))
(unless (cg-get game :vul) (cg-put game :vul (make-vector 2 nil)))
(cg-put game :message "Auction: compose a bid and press RET, or p/d to pass/double.")
game))
(defun cg-bridge--high-bid (game)
"Return the highest (LEVEL . STRAIN) bid so far, or nil."
(cl-loop for (_s . call) in (cg-get game :calls)
when (consp call) return call))
(defun cg-bridge--high-bidder (game)
"Return the seat that made the highest bid, or nil."
(cl-loop for (s . call) in (cg-get game :calls)
when (consp call) return s))
(defun cg-bridge--call> (a b)
"Return non-nil when bid A is higher than bid B (each (LEVEL . STRAIN))."
(or (null b)
(> (car a) (car b))
(and (= (car a) (car b)) (> (cdr a) (cdr b)))))
(defun cg-bridge--legal-call-p (game call)
"Return non-nil when CALL is legal now in GAME."
(let ((high (cg-bridge--high-bid game))
(hb (cg-bridge--high-bidder game)))
(pcase call
('pass t)
('double (and high (/= (cg-bridge--side hb) (cg-bridge--side (cg-get game :bidder)))
(= (cg-get game :doubled) 0)))
('redouble (and high (= (cg-bridge--side hb) (cg-bridge--side (cg-get game :bidder)))
(= (cg-get game :doubled) 1)))
(_ (and (consp call) (>= (car call) 1) (<= (car call) 7)
(cg-bridge--call> call high))))))
(defun cg-bridge--apply-call (game seat call)
"Record CALL by SEAT and update doubling state."
(cg-put game :calls (cons (cons seat call) (cg-get game :calls)))
(pcase call
('double (cg-put game :doubled 1))
('redouble (cg-put game :doubled 2))
((pred consp) (cg-put game :doubled 0)))
(cg-put game :bidder (mod (1+ seat) 4)))
(defun cg-bridge--auction-done-p (game)
"Return non-nil when the auction has ended.
Sets up the contract (or a pass-out) as a side effect."
(let* ((calls (cg-get game :calls)) (n (length calls)))
(cond
;; four passes with no bid: passed out
((and (= n 4) (cl-every (lambda (c) (eq (cdr c) 'pass)) calls))
(cg-put game :phase 'passed-out) t)
;; a bid then three passes
((and (cg-bridge--high-bid game)
(>= n 3)
(cl-every (lambda (c) (eq (cdr c) 'pass))
(cl-subseq calls 0 3)))
(cg-bridge--establish-contract game) t)
(t nil))))
(defun cg-bridge--establish-contract (game)
"Set the contract, declarer, and start of play from the finished auction."
(let* ((bid (cg-bridge--high-bid game))
(side (cg-bridge--side (cg-bridge--high-bidder game)))
(strain (cdr bid))
(declarer
;; first player of SIDE to have named STRAIN
(cl-loop for (s . call) in (reverse (cg-get game :calls))
when (and (consp call) (= (cdr call) strain)
(= (cg-bridge--side s) side))
return s)))
(cg-put game :contract bid)
(cg-put game :declarer declarer)
(cg-put game :dummy (mod (+ declarer 2) 4))
(cg-put game :phase 'play)
(cg-put game :leader (mod (1+ declarer) 4))
(cg-put game :turn (mod (1+ declarer) 4))
(cg-put game :trick nil)
(cg-put game :tricks 0)
(cg-put game :cursor 0)
(cg-put game :message
(format "Contract: %s by %s. %s leads."
(cg-bridge--contract-string game)
(aref cg-bridge-seat-names declarer)
(aref cg-bridge-seat-names (cg-get game :leader))))))
(defun cg-bridge--contract-string (game)
"Return a label for GAME's contract, e.g. \"4NT x\"."
(let ((c (cg-get game :contract)) (d (cg-get game :doubled)))
(if (null c) "passed out"
(format "%d%s%s" (car c) (aref cg-bridge-strains (cdr c))
(pcase d (1 " x") (2 " xx") (_ ""))))))
;;;; Play mechanics
(defun cg-bridge--trump (game)
"Return the trump suit index for GAME, or nil for no-trump."
(and (cg-get game :contract) (aref cg-bridge--strain-suit (cdr (cg-get game :contract)))))
(defun cg-bridge--led-suit (game)
"Return the suit led to the current trick, or nil."
(let ((tr (cg-get game :trick)))
(and tr (car (cdr (car (last tr)))))))
(defun cg-bridge--legal-play-p (game seat card)
"Return non-nil when SEAT may play CARD now (follow suit if able)."
(let ((hand (cg-bridge--hand game seat)) (led (cg-bridge--led-suit game)))
(and (member card hand)
(or (null led)
(= (car card) led)
(not (cl-some (lambda (c) (= (car c) led)) hand))))))
(defun cg-bridge--legal-plays (game seat)
"Return SEAT's legal cards now."
(cl-remove-if-not (lambda (c) (cg-bridge--legal-play-p game seat c))
(cg-bridge--hand game seat)))
(defun cg-bridge--trick-winner (plays trump)
"Return the winning seat of complete PLAYS ((SEAT . CARD), play order)."
(let ((best (car plays)))
(dolist (p (cdr plays))
(let ((bc (cdr best)) (pc (cdr p)))
(cond
((and trump (= (car pc) trump) (/= (car bc) trump)) (setq best p))
((and (= (car pc) (car bc)) (> (cdr pc) (cdr bc))) (setq best p)))))
(car best)))
(defun cg-bridge--play-card (game seat card)
"Have SEAT play CARD; resolve and score the trick when it completes."
(cg-bridge--set-hand game seat (remove card (cg-bridge--hand game seat)))
(cg-put game :trick (cons (cons seat card) (cg-get game :trick)))
;; expose the dummy after the opening lead
(unless (cg-get game :exposed)
(cg-put game :exposed t))
(if (= 4 (length (cg-get game :trick)))
(let ((w (cg-bridge--trick-winner (reverse (cg-get game :trick))
(cg-bridge--trump game))))
(when (= (cg-bridge--side w) (cg-bridge--side (cg-get game :declarer)))
(cg-put game :tricks (1+ (cg-get game :tricks))))
(cg-put game :trick nil)
(cg-put game :leader w)
(cg-put game :turn w)
(cg-put game :last-winner w)
(when (cl-every #'null (append (cg-get game :hands) nil))
(cg-bridge--score-deal game))
w)
(cg-put game :turn (mod (1+ seat) 4))
nil))
;;;; Scoring (rubber)
(defun cg-bridge--undertrick-points (n doubled vul)
"Return defender points for N undertricks at DOUBLED level and VUL state."
(cond
((= doubled 0) (* n (if vul 100 50)))
(t (let ((mult (if (= doubled 2) 2 1)) (sum 0))
(dotimes (i n)
(setq sum (+ sum (* mult (if vul (if (= i 0) 200 300)
(cond ((= i 0) 100) ((< i 3) 200) (t 300)))))))
sum))))
(defun cg-bridge--deal-score (level strain doubled vul tricks)
"Return a plist scoring a contract result.
LEVEL/STRAIN/DOUBLED describe the contract, VUL the declarer's
vulnerability, and TRICKS the declarer side's trick count. Keys:
:below contracted points, :datk declarer bonus points above the line,
:defend defender points, :result tricks over/under the contract."
(let* ((need (+ 6 level)) (result (- tricks need))
(mult (pcase doubled (0 1) (1 2) (2 4)))
(below 0) (datk 0) (defend 0))
(if (>= result 0)
(progn
(setq below (* mult (if (= strain 4) (+ 40 (* 30 (1- level)))
(* (if (<= strain 1) 20 30) level))))
(when (> result 0)
(setq datk (+ datk (if (= doubled 0)
(* result (if (= strain 4) 30 (if (<= strain 1) 20 30)))
(* result (* (if (= doubled 2) 2 1) (if vul 200 100)))))))
(when (> doubled 0) (setq datk (+ datk (if (= doubled 2) 100 50))))
(cond ((= level 6) (setq datk (+ datk (if vul 750 500))))
((= level 7) (setq datk (+ datk (if vul 1500 1000))))))
(setq defend (cg-bridge--undertrick-points (- result) doubled vul)))
(list :below below :datk datk :defend defend :result result)))
(defun cg-bridge--score-deal (game)
"Score the finished deal into GAME's rubber state."
(let* ((c (cg-get game :contract)) (level (car c)) (strain (cdr c))
(decl (cg-get game :declarer)) (side (cg-bridge--side decl))
(opp (- 1 side)) (doubled (cg-get game :doubled))
(vul (aref (cg-get game :vul) side))
(sc (cg-bridge--deal-score level strain doubled vul (cg-get game :tricks)))
(below (cg-get game :below)) (above (cg-get game :above)))
(aset below side (+ (aref below side) (plist-get sc :below)))
(aset above side (+ (aref above side) (plist-get sc :datk)))
(aset above opp (+ (aref above opp) (plist-get sc :defend)))
(cg-put game :deal-result sc)
;; game / rubber bookkeeping
(when (>= (aref below side) 100)
(let ((games (cg-get game :games)))
(aset games side (1+ (aref games side)))
(aset (cg-get game :vul) side t)
(aset below 0 0) (aset below 1 0)
(when (>= (aref games side) 2)
(aset above side (+ (aref above side)
(if (>= (aref games opp) 1) 500 700)))
(cg-put game :rubber-winner side))))
(cg-put game :phase 'scored)
(cg-put game :message
(format "%s: %s. %s"
(cg-bridge--contract-string game)
(let ((r (plist-get sc :result)))
(cond ((>= r 0) (format "made +%d" r))
(t (format "down %d" (- r)))))
(if (cg-get game :rubber-winner)
(format "%s win the rubber! (n: new rubber)"
(if (= side 0) "You and North" "East and West"))
"(n: next deal)")))))
;;;; AI -- bidding
(cl-defmethod cg-bridge--ai-call ((game cg-bridge-game) seat)
"Return a call for AI SEAT from a small natural system."
(let* ((hand (cg-bridge--hand game seat)) (hcp (cg-bridge--hcp hand))
(high (cg-bridge--high-bid game)) (hb (cg-bridge--high-bidder game))
(ours (and high (= (cg-bridge--side hb) (cg-bridge--side seat)))))
(cond
((null high) ; opening
(cond ((and (cg-bridge--balanced-p hand) (>= hcp 15) (<= hcp 17)) (cons 1 4))
((and (cg-bridge--balanced-p hand) (>= hcp 20) (<= hcp 21)) (cons 2 4))
((>= hcp 12)
(let ((suit (cg-bridge--longest hand)))
(cons 1 (aref cg-bridge--suit-strain suit))))
(t 'pass)))
(ours ; partner has the contract
(let* ((est (+ hcp 13)) (hl (car high)) (hs (cdr high))
(fit (or (= hs 4)
(>= (cg-bridge--suit-len
hand (aref cg-bridge--strain-suit hs)) 3))))
(if (and fit (>= est 26) (< hl 4)
(cg-bridge--legal-call-p
game (cond ((= hs 4) (cons 3 4))
((>= hs 2) (cons 4 hs))
(t (cons 5 hs)))))
(cond ((= hs 4) (cons 3 4)) ((>= hs 2) (cons 4 hs)) (t (cons 5 hs)))
'pass)))
(t ; opponents have the contract
(let* ((suit (cg-bridge--longest hand))
(len (cg-bridge--suit-len hand suit))
(st (aref cg-bridge--suit-strain suit))
(cand (if (> st (cdr high)) (cons (car high) st)
(cons (1+ (car high)) st))))
(if (and (>= hcp 11) (>= len 5) (<= (car cand) 3)
(cg-bridge--legal-call-p game cand))
cand 'pass))))))
;;;; AI -- play
(cl-defmethod cg-bridge--ai-play ((game cg-bridge-game) seat)
"Return a card for AI SEAT: win cheaply or shed low."
(let* ((legal (cg-bridge--legal-plays game seat))
(trump (cg-bridge--trump game)) (trick (cg-get game :trick)))
(if (null trick)
;; leading: low from the longest non-trump suit, else lowest
(car (sort (copy-sequence legal)
(lambda (a b) (< (cdr a) (cdr b)))))
(let* ((order (reverse trick))
(cur (cg-bridge--trick-winner order trump))
(partner (= (cg-bridge--side cur) (cg-bridge--side seat)))
(winners (cl-remove-if-not
(lambda (c) (= seat (cg-bridge--trick-winner
(append order (list (cons seat c))) trump)))
legal)))
(cond
;; partner already winning: throw the lowest card
((and partner (>= (length trick) 1))
(car (sort (copy-sequence legal) (lambda (a b) (< (cdr a) (cdr b))))))
;; can win: take it with the cheapest winner
(winners (car (sort winners (lambda (a b) (< (cdr a) (cdr b))))))
;; cannot win: discard lowest
(t (car (sort (copy-sequence legal) (lambda (a b) (< (cdr a) (cdr b)))))))))))
(defun cg-bridge--controls (game)
"Return the list of seats the human controls during play."
(let ((decl (cg-get game :declarer)))
(cond ((null decl) nil)
((= decl 0) '(0 2)) ; South declares: play hand + dummy
((= decl 2) nil) ; North declares: AI plays both
(t '(0))))) ; South defends
(defun cg-bridge--auto-seat-p (game seat)
"Return non-nil when SEAT is played automatically (by AI) in GAME."
(not (memq seat (cg-bridge--controls game))))
(defun cg-bridge--run-play (game)
"Advance AI plays until a human-controlled seat must act or the deal ends."
(let ((guard 0))
(while (and (eq (cg-get game :phase) 'play)
(cg-bridge--auto-seat-p game (cg-get game :turn))
(< guard 60))
(setq guard (1+ guard))
(cg-bridge--play-card game (cg-get game :turn)
(cg-bridge--ai-play game (cg-get game :turn))))))
(defun cg-bridge--run-auction (game)
"Advance the auction through AI seats until South must call or it ends."
(let ((guard 0))
(while (and (eq (cg-get game :phase) 'auction) (/= (cg-get game :bidder) 0)
(< guard 40))
(setq guard (1+ guard))
(let* ((s (cg-get game :bidder)) (call (cg-bridge--ai-call game s)))
(unless (cg-bridge--legal-call-p game call) (setq call 'pass))
(cg-bridge--apply-call game s call)
(cg-bridge--auction-done-p game)))
(when (eq (cg-get game :phase) 'play) (cg-bridge--run-play game))))
;;;; UI
(defvar-local cg-bridge--game nil "The Bridge game in the current buffer.")
(defun cg-bridge--hand-by-suit (cards)
"Return CARDS grouped into four lines by suit, as a string."
(let ((out '()))
(dolist (s '(0 3 2 1)) ; S H D C
(let ((in (cg-bridge--sort (cl-remove-if-not (lambda (c) (= (car c) s)) cards))))
(push (format " %s %s\n" (cg-suit-glyph s)
(if in (mapconcat (lambda (c) (aref cg-bridge-ranks (cdr c))) in " ")
"--"))
out)))
(apply #'concat (nreverse out))))
(defun cg-bridge--auction-string (game)
"Return a compact record of the auction so far."
(let ((calls (reverse (cg-get game :calls))) (out '()))
(dolist (sc calls)
(push (format "%s:%s" (aref cg-bridge-seat-names (car sc))
(pcase (cdr sc)
('pass "pass") ('double "X") ('redouble "XX")
(c (format "%d%s" (car c) (aref cg-bridge-strains (cdr c))))))
out))
(if out (mapconcat #'identity (nreverse out) " ") "(no calls yet)")))
(cl-defmethod cg-render ((game cg-bridge-game))
"Return a propertized depiction of the Bridge GAME."
(let* ((out '()) (phase (cg-get game :phase)) (cursor (cg-get game :cursor)))
(push " Bridge\n" out)
(push (format " Rubber: You/North games %d East/West games %d%s\n"
(aref (cg-get game :games) 0) (aref (cg-get game :games) 1)
(let ((v (cg-get game :vul)))
(format " (vul: %s)"
(cond ((and (aref v 0) (aref v 1)) "both")
((aref v 0) "N-S") ((aref v 1) "E-W") (t "none")))))
out)
(push (format " Below: You/N %d E/W %d Above: You/N %d E/W %d\n\n"
(aref (cg-get game :below) 0) (aref (cg-get game :below) 1)
(aref (cg-get game :above) 0) (aref (cg-get game :above) 1))
out)
(pcase phase
('auction
(push (format " Auction so far: %s\n\n" (cg-bridge--auction-string game)) out)
(push (format " Compose: %d %s (Up/Down level, Left/Right strain)\n\n"
(cg-get game :bid-level)
(aref cg-bridge-strains (cg-get game :bid-strain)))
out))
((or 'play 'scored 'passed-out)
(push (format " Contract: %s by %s Declarer tricks: %d\n"
(cg-bridge--contract-string game)
(if (cg-get game :declarer)
(aref cg-bridge-seat-names (cg-get game :declarer)) "--")
(cg-get game :tricks))
out)
(when (and (cg-get game :exposed) (cg-get game :dummy))
(push (format "\n Dummy (%s):\n%s"
(aref cg-bridge-seat-names (cg-get game :dummy))
(cg-bridge--hand-by-suit (cg-bridge--hand game (cg-get game :dummy))))
out))
(push "\n Trick: " out)
(if (cg-get game :trick)
(dolist (p (reverse (cg-get game :trick)))
(push (format "%s:%s " (aref cg-bridge-seat-names (car p))
(cg-bridge-card-string (cdr p))) out))
(push "(empty)" out))
(push "\n" out)))
;; the human's hand (South), or the seat being played from when it is dummy
(let* ((act (if (and (eq phase 'play) (memq (cg-get game :turn)
(cg-bridge--controls game)))
(cg-get game :turn) 0))
(hand (cg-bridge--sort (cg-bridge--hand game act))))
(push (format "\n %s%s:\n "
(aref cg-bridge-seat-names act)
(cond ((eq phase 'auction) " (you)")
((= act 0) " (you)")
(t " (dummy, you play)")))
out)
(if (eq phase 'play)
(let ((i 0))
(dolist (c hand)
(let ((cs (cg-bridge-card-string c)) (faces nil))
(when (cg-red-suit-p (car c)) (push 'cg-red-suit faces))
(when (and (= (cg-get game :turn) act)
(cg-bridge--legal-play-p game act c)) (push 'cg-hint faces))
(when (= i cursor) (push 'cg-cursor faces))
(push (propertize (format "%4s" cs) 'face (or faces 'default)) out))
(setq i (1+ i))))
(push (cg-bridge--hand-by-suit hand) out)))
(push (format "\n\n %s\n" (cg-get game :message)) out)
(apply #'concat (nreverse out))))
(defun cg-bridge--redisplay ()
(let ((game cg-bridge--game) (inhibit-read-only t))
(setq-local mode-line-process (format " [%s]" (cg-get game :phase)))
(erase-buffer) (insert (cg-render game)) (goto-char (point-min))))
;;;; Auction commands
(defun cg-bridge-bid-level-up ()
"Raise the level being composed."
(interactive)
(let ((g cg-bridge--game))
(cg-put g :bid-level (min 7 (1+ (cg-get g :bid-level))))
(cg-bridge--redisplay)))
(defun cg-bridge-bid-level-down ()
"Lower the level being composed."
(interactive)
(let ((g cg-bridge--game))
(cg-put g :bid-level (max 1 (1- (cg-get g :bid-level))))
(cg-bridge--redisplay)))
(defun cg-bridge-bid-strain-left ()
"Move the composed strain down (toward clubs)."
(interactive)
(let ((g cg-bridge--game))
(cg-put g :bid-strain (max 0 (1- (cg-get g :bid-strain))))
(cg-bridge--redisplay)))
(defun cg-bridge-bid-strain-right ()
"Move the composed strain up (toward no-trump)."
(interactive)
(let ((g cg-bridge--game))
(cg-put g :bid-strain (min 4 (1+ (cg-get g :bid-strain))))
(cg-bridge--redisplay)))
(defun cg-bridge--after-call (g)
"Resolve end-of-auction and run AI after South calls in G."
(unless (cg-bridge--auction-done-p g)
(cg-bridge--run-auction g))
(when (eq (cg-get g :phase) 'play) (cg-bridge--run-play g))
(cg-bridge--redisplay))
(defun cg-bridge-bid ()
"Make the composed bid."
(interactive)
(let* ((g cg-bridge--game)
(call (cons (cg-get g :bid-level) (cg-get g :bid-strain))))
(cond
((not (eq (cg-get g :phase) 'auction)) (cg-put g :message "Not bidding now."))
((/= (cg-get g :bidder) 0) (cg-put g :message "Not your turn."))
((not (cg-bridge--legal-call-p g call))
(cg-put g :message "That bid is too low."))
(t (cg-bridge--apply-call g 0 call) (cg-bridge--after-call g)))
(cg-bridge--redisplay)))
(defun cg-bridge-pass ()
"Pass in the auction."
(interactive)
(let ((g cg-bridge--game))
(if (and (eq (cg-get g :phase) 'auction) (= (cg-get g :bidder) 0))
(progn (cg-bridge--apply-call g 0 'pass) (cg-bridge--after-call g))
(cg-put g :message "Nothing to pass on."))
(cg-bridge--redisplay)))
(defun cg-bridge-double ()
"Double (or redouble) in the auction."
(interactive)
(let* ((g cg-bridge--game)
(call (if (= (cg-get g :doubled) 1) 'redouble 'double)))
(if (and (eq (cg-get g :phase) 'auction) (= (cg-get g :bidder) 0)
(cg-bridge--legal-call-p g call))
(progn (cg-bridge--apply-call g 0 call) (cg-bridge--after-call g))
(cg-put g :message "You cannot double now."))
(cg-bridge--redisplay)))
;;;; Play commands
(defun cg-bridge--act-hand (g)
"Return the hand the cursor currently indexes (the seat to act)."
(let ((act (if (memq (cg-get g :turn) (cg-bridge--controls g)) (cg-get g :turn) 0)))
(cg-bridge--sort (cg-bridge--hand g act))))
(defun cg-bridge-left ()
"Move the cursor left."
(interactive)
(let* ((g cg-bridge--game) (n (length (cg-bridge--act-hand g))))
(cond ((eq (cg-get g :phase) 'auction) (cg-bridge-bid-strain-left))
(t (when (> n 0) (cg-put g :cursor (mod (1- (cg-get g :cursor)) n)))
(cg-bridge--redisplay)))))
(defun cg-bridge-right ()
"Move the cursor right."
(interactive)
(let* ((g cg-bridge--game) (n (length (cg-bridge--act-hand g))))
(cond ((eq (cg-get g :phase) 'auction) (cg-bridge-bid-strain-right))
(t (when (> n 0) (cg-put g :cursor (mod (1+ (cg-get g :cursor)) n)))
(cg-bridge--redisplay)))))
(defun cg-bridge-up ()
"Raise the bid level (auction only)."
(interactive)
(if (eq (cg-get cg-bridge--game :phase) 'auction) (cg-bridge-bid-level-up)
(cg-bridge--redisplay)))
(defun cg-bridge-down ()
"Lower the bid level (auction only)."
(interactive)
(if (eq (cg-get cg-bridge--game :phase) 'auction) (cg-bridge-bid-level-down)
(cg-bridge--redisplay)))
(defun cg-bridge-play ()
"Play the cursor card, or make the composed bid during the auction."
(interactive)
(let ((g cg-bridge--game))
(if (eq (cg-get g :phase) 'auction)
(cg-bridge-bid)
(let* ((turn (cg-get g :turn)))
(cond
((not (eq (cg-get g :phase) 'play)) (cg-put g :message "Press n to continue."))
((not (memq turn (cg-bridge--controls g)))
(cg-put g :message "Wait for your turn."))
(t (let ((card (nth (cg-get g :cursor) (cg-bridge--sort (cg-bridge--hand g turn)))))
(if (or (null card) (not (cg-bridge--legal-play-p g turn card)))
(cg-put g :message "You must follow suit.")
(cg-bridge--play-card g turn card)
(cg-put g :cursor 0)
(when (eq (cg-get g :phase) 'play) (cg-bridge--run-play g))))))
(cg-bridge--redisplay)))))
(defun cg-bridge-new ()
"Deal the next hand, or a fresh rubber when one is over."
(interactive)
(let ((g cg-bridge--game))
(when (or (cg-get g :rubber-winner))
(cg-put g :below (make-vector 2 0)) (cg-put g :above (make-vector 2 0))
(cg-put g :games (make-vector 2 0)) (cg-put g :vul (make-vector 2 nil))
(cg-put g :rubber-winner nil))
(cg-put g :dealer (mod (1+ (or (cg-get g :dealer) 0)) 4))
(cg-bridge--deal g)
(cg-bridge--run-auction g)
(cg-bridge--redisplay)))
(defun cg-bridge-redraw () "Redraw." (interactive) (cg-bridge--redisplay))
(defun cg-bridge-help () "Describe the controls." (interactive)
(message "Auction: Up/Down level, Left/Right strain, RET bid, p pass, d double. Play: arrows + RET. n: next"))
(defvar cg-bridge-mode-map
(let ((map (make-sparse-keymap)))
(define-key map (kbd "<left>") #'cg-bridge-left)
(define-key map (kbd "<right>") #'cg-bridge-right)
(define-key map (kbd "<up>") #'cg-bridge-up)
(define-key map (kbd "<down>") #'cg-bridge-down)
(define-key map (kbd "RET") #'cg-bridge-play)
(define-key map "p" #'cg-bridge-pass)
(define-key map "d" #'cg-bridge-double)
(define-key map "n" #'cg-bridge-new)
(define-key map "g" #'cg-bridge-redraw)
(define-key map "?" #'cg-bridge-help)
map)
"Keymap for `cg-bridge-mode'.")
(define-derived-mode cg-bridge-mode special-mode "Bridge"
"Major mode for contract Bridge."
(setq-local truncate-lines t))
;;;###autoload
(defun cg-bridge ()
"Play contract Bridge against the computer."
(interactive)
(let ((buf (get-buffer-create "*Bridge*")))
(with-current-buffer buf
(cg-bridge-mode)
(setq cg-bridge--game (cg-bridge-game))
(cg-put cg-bridge--game :dealer 0)
(cg-bridge--deal cg-bridge--game)
(cg-bridge--run-auction cg-bridge--game)
(cg-bridge--redisplay))
(switch-to-buffer buf)))
(provide 'cg-bridge)
;;; cg-bridge.el ends here