path: root/internal/game/casino.go

package game

import (
	"errors"
	"fmt"
	"os"
	"strconv"
	"strings"
	"unicode/utf8"

	"thehouseoficarus/internal/cardart"
	"thehouseoficarus/internal/casino"
	"thehouseoficarus/internal/color"
	"thehouseoficarus/internal/net"
	"thehouseoficarus/internal/persistence"
	"thehouseoficarus/internal/player"
)

type casinoWallet struct {
	g *Game
	p *player.Player
}

// Wager debits the stake durably. Order of operations: durable journal
// record FIRST (with balance checkpoints), then the in-memory mutation,
// then the character save, then the record is registered as an OUTSTANDING
// STAKE. It is NOT settled here: it stays open until the round resolves
// (casino.Wallet.ResolveStakes) or is refunded (RefundOutstanding). An open
// record at startup recovery means the round state was lost in a crash and
// the stake is refunded — the documented refund-on-crash policy.
//
// A failed save reverts the in-memory mutation and voids the record: no
// charge is kept in memory, and the error distinguishes persistence failure
// from insufficient funds.
func (w casinoWallet) Wager(amount int) (casino.Wager, error) {
	if amount <= 0 {
		return casino.Wager{}, casino.ErrInsufficientFunds
	}
	creditsBefore := w.p.Credits
	chipsBefore := countChips(w.p)
	chips := chipsBefore
	if chips > amount {
		chips = amount
	}
	credits := amount - chips
	if creditsBefore < credits {
		return casino.Wager{}, casino.ErrInsufficientFunds
	}
	rec, err := w.g.Economy.start("wager", w.p, chips, credits,
		creditsBefore, creditsBefore-credits, chipsBefore, chipsBefore-chips)
	if err != nil {
		return casino.Wager{}, casino.ErrWalletPersistence
	}
	if chips > 0 {
		w.p.RemoveItem("chips", chips)
	}
	w.p.Credits -= credits
	if err := w.g.AccountStore.SaveCharacter(w.p); err != nil {
		if errors.Is(err, persistence.ErrDurabilityUncertain) {
			// The character file was replaced but the directory sync failed:
			// the debit may be durable. Keep the in-memory debit and the
			// journal record OPEN instead of voiding it, so recovery compares
			// checkpoints against whatever file survived and either voids or
			// refunds consistently. Proceeding is safe: the record stays open
			// (refundable) until the round resolves.
			fmt.Fprintf(os.Stderr, "casino wager: %s save durability uncertain: %v — record kept open\n", w.p.Name, err)
			w.g.Economy.registerStake(rec)
			return casino.Wager{Total: amount, Chips: chips, Credits: credits, ID: rec.ID}, nil
		}
		// Revert the in-memory mutation: the play must not proceed on a
		// stake that could not be made durable.
		if chips > 0 {
			if !w.g.giveChips(w.p, chips) {
				// Cannot happen (the debit just freed or reduced the chips
				// stack), but surface it instead of silently losing chips.
				fmt.Fprintf(os.Stderr, "casino wager revert: no inventory room for %d chips\n", chips)
			}
		}
		w.p.Credits += credits
		w.g.Economy.void(rec)
		return casino.Wager{}, casino.ErrWalletPersistence
	}
	// The record stays open as an outstanding stake until the round
	// resolves; recovery refunds open stakes after a crash.
	w.g.Economy.registerStake(rec)
	return casino.Wager{Total: amount, Chips: chips, Credits: credits, ID: rec.ID}, nil
}

// PayCredits applies a payout durably. The journal record is written first;
// if the save fails, the record stays open and startup recovery re-pays it
// (the player is owed the settlement).
func (w casinoWallet) PayCredits(amount int) error {
	return w.payCreditsFlagged(amount, false, nil)
}

// PayStakeCover applies a settlement that INCLUDES the return of the listed
// stake wager IDs (a table hand pays its stake back inside the payout). The
// record is journaled with that linkage, so a shutdown refund never returns
// those stakes a second time; recovery re-applies the owed payout instead.
func (w casinoWallet) PayStakeCover(amount int, stakeIDs []string) error {
	return w.payCreditsFlagged(amount, false, stakeIDs)
}

// payCreditsFlagged journals and applies a credit payout; a settlement
// payout (refund=false) proves the round resolved during recovery, while a
// refund payout (refund=true) marks a stake RETURNED at shutdown/eviction
// (its chip part returns in chips, not through this credit payout).
// stakeIDs, when non-empty, records WHICH open stakes this settlement
// returns (table hands); empty means the payout resolves the round without
// a linked stake return (slots winnings).
func (w casinoWallet) payCreditsFlagged(amount int, refund bool, stakeIDs []string) error {
	if amount <= 0 {
		return nil
	}
	creditsBefore := w.p.Credits
	chipsBefore := countChips(w.p)
	creditsAfter, capErr := addCreditsChecked(creditsBefore, amount)
	// The journal record is written FIRST, even when the economy cap
	// blocks the payout: a won settlement must never be silently dropped.
	// With the cap blocking, the balance is unchanged and the open record
	// keeps the owed amount durable; startup recovery re-applies it once
	// the balance has room below the cap.
	rec, err := w.g.Economy.startKind("payout", refund, stakeIDs, w.p, 0, amount,
		creditsBefore, creditsAfter, chipsBefore, chipsBefore)
	if err != nil {
		// The journal is unavailable (persistent append failure). Last
		// resort: pay through the character file only. The save below is
		// the commit point — the money is durable even without a journal
		// record, so the settlement may be announced as paid. The stake
		// resolution evidence (recordStakeEvidence) recorded in that same
		// file keeps recovery from treating the round as unresolved;
		// without a payout record, an open wager can no longer be
		// distinguished from a lost one, so the balance itself is the only
		// record of what happened.
		if capErr != nil {
			return capErr
		}
		w.p.Credits = creditsAfter
		// The character file is the only durable record, so it must also
		// carry the resolution evidence for the stakes this settlement
		// resolves: a crash before the games' own ResolveStakes call would
		// otherwise leave the wager records open with checkpoint balances
		// that no longer match, and recovery would refund chip stakes the
		// paid settlement had already consumed. Only the settled stakes are
		// recorded (see recordStakeEvidence), so a sibling hand's stake stays
		// refundable. The single save below is the commit point for the
		// payout AND the resolution.
		resolved := w.recordStakeEvidence(stakeIDs)
		if serr := w.g.AccountStore.SaveCharacter(w.p); serr != nil {
			w.p.Credits = creditsBefore
			if resolved > 0 {
				w.p.ResolvedStakes = w.p.ResolvedStakes[:len(w.p.ResolvedStakes)-resolved]
			}
			return casino.ErrWalletPersistence
		}
		kind := "settlement"
		if refund {
			kind = "refund"
		}
		fmt.Fprintf(os.Stderr, "economy: %s payout of %d credits for %s could not be journaled; the character file is the only durable record\n", kind, amount, w.p.Name)
		return nil
	}
	if capErr != nil {
		return capErr
	}
	w.p.Credits = creditsAfter
	// Record the payout in the character's open-payout evidence list: the
	// save below is the commit point, and the file itself then proves the
	// amount is included in the balance. Recovery reads this list instead
	// of guessing from balance checkpoints, which unrelated credit changes
	// (a shop sale, a bank deposit) can replicate by coincidence.
	w.p.OpenPayouts = append(w.p.OpenPayouts, rec.ID)
	if err := w.g.AccountStore.SaveCharacter(w.p); err != nil {
		w.p.Credits = creditsBefore
		removeOpenPayout(w.p, rec.ID)
		// Keep the record open: recovery re-pays on next startup, since a
		// reported win must be durable.
		return casino.ErrWalletPersistence
	}
	// The evidence entry may only be dropped once the settled marker is
	// durable; while the marker is still open, the file's membership is
	// what proves durability to recovery.
	if w.g.Economy.settleDurable(rec) {
		removeOpenPayout(w.p, rec.ID)
	}
	return nil
}

// ResolveStakes marks every outstanding stake for the player settled: the
// round resolved (won, lost, pushed, or forfeited), so startup recovery
// must no longer refund it. When the journal cannot persist the settled
// markers, the record IDs are recorded in the character file as durable
// resolution evidence (player.Player.ResolvedStakes) so recovery still
// honors the resolution instead of refunding an already-resolved round.
func (w casinoWallet) ResolveStakes() {
	unresolved := w.g.Economy.ResolveStakes(economyKey(w.p))
	w.recordResolutionEvidence(unresolved)
}

// recordResolutionEvidence persists file-side resolution evidence for stake
// records whose settled markers could not be journaled. The character file
// then proves the round resolved even though the journal could not record
// its marker, so recovery still honors the resolution instead of refunding
// an already-resolved round.
func (w casinoWallet) recordResolutionEvidence(unresolved []*economyRecord) {
	if len(unresolved) == 0 {
		return
	}
	changed := false
	for _, rec := range unresolved {
		if !resolvedStakeRecorded(w.p, rec.ID) {
			w.p.ResolvedStakes = append(w.p.ResolvedStakes, rec.ID)
			changed = true
		}
	}
	if !changed {
		return
	}
	if err := w.g.AccountStore.SaveCharacter(w.p); err != nil {
		fmt.Fprintf(os.Stderr, "casino resolve stakes: evidence save for %s: %v\n", w.p.Name, err)
	}
}

// ResolveStake settles ONE outstanding stake by wallet handle: the hand it
// belongs to was paid (its return is inside the settlement) or lost, so it
// must never be refunded. Unresolvable markers fall back to the same file-
// side evidence the bulk ResolveStakes uses.
func (w casinoWallet) ResolveStake(stakeID string) {
	if stakeID == "" {
		return
	}
	unresolved := w.g.Economy.ResolveStakeByID(economyKey(w.p), stakeID)
	w.recordResolutionEvidence(unresolved)
}

// recordStakeEvidence adds the stakes the current settlement resolves to the
// file-side resolution evidence list and returns how many IDs were newly
// recorded. Used when the economy journal is unavailable: the open wager
// record IDs in the character file prove the round resolved even though no
// settled marker (or payout record) could ever be journaled. The caller
// must persist the character file for the evidence to count.
//
// stakeIDs are the stakes the payout settles (a table hand lists its own
// hand's stakes). Only those are recorded: a sibling hand's stake is settled
// by its own payout, so marking it resolved here would suppress the refund a
// crash before that payout must still produce. An empty list (a slots payout
// links no stake) settles the round that consumed the stake, so every open
// stake of the player is evidence.
func (w casinoWallet) recordStakeEvidence(stakeIDs []string) int {
	added := 0
	for _, rec := range w.g.Economy.openStakes(economyKey(w.p)) {
		if len(stakeIDs) > 0 && !containsString(stakeIDs, rec.ID) {
			continue
		}
		if !resolvedStakeRecorded(w.p, rec.ID) {
			w.p.ResolvedStakes = append(w.p.ResolvedStakes, rec.ID)
			added++
		}
	}
	return added
}

// RefundOutstanding returns every outstanding stake to the player: chips
// come back as chips, credits through the durable payout path. The stakes
// are resolved only once the return is durable; on failure the chip return
// is rolled back out of memory and the open records drive recovery instead.
//
// Stakes already accounted for by an open settlement payout are NOT
// refunded: a journaled table settlement includes its hand's stake return
// and recovery re-applies that owed payout, so refunding the stake here
// would pay the round twice (the returned credits then arrive on top of
// the stake). The stakes are resolved; their money arrives with the
// re-applied settlement.
func (w casinoWallet) RefundOutstanding() (chips, credits int, err error) {
	for _, rec := range w.g.Economy.openStakes(economyKey(w.p)) {
		if resolvedStakeRecorded(w.p, rec.ID) {
			// Already resolved through file-side evidence: recovery
			// settles it, never refunds it.
			continue
		}
		if w.g.Economy.stakeCovered(rec) {
			// The covering settlement is journaled and owed: resolving
			// the stake defers its return to the payout re-application.
			continue
		}
		chips += rec.Chips
		credits += rec.Credit
	}
	if chips <= 0 && credits <= 0 {
		w.ResolveStakes()
		return 0, 0, nil
	}
	if chips > 0 {
		if !w.g.giveChips(w.p, chips) {
			// No inventory room for the chip return: nothing was refunded.
			// The stakes stay open so recovery (or a later attempt once the
			// player has inventory space) can complete the refund; callers
			// report the stake as recorded rather than refunded, never as
			// silently dropped.
			return 0, 0, casino.ErrWalletPersistence
		}
	}
	if credits > 0 {
		if err := w.payCreditsFlagged(credits, true, nil); err != nil {
			if chips > 0 {
				// Roll the chip return back out of memory: the durable
				// refund will re-apply both amounts from the open records.
				w.p.RemoveItem("chips", chips)
			}
			return chips, credits, err
		}
	} else if chips > 0 {
		// A chips-only refund needs its own durable save.
		if err := w.g.AccountStore.SaveCharacter(w.p); err != nil {
			w.p.RemoveItem("chips", chips)
			return chips, 0, casino.ErrWalletPersistence
		}
	}
	w.ResolveStakes()
	return chips, credits, nil
}

// casinoAffordable is the most a player can wager: chips are spent first,
// then credits.
func casinoAffordable(p *player.Player) int { return p.Credits + countChips(p) }

// leaveCasinoGames departs every casino game the player participates in
// using the graceful leave policy each game defines for player-initiated
// exits (the same path the "stop" command takes): a table with a wager
// committed to the round in flight refuses and emits its own refusal
// message, machines stop auto-bet or are left outright. It reports whether
// the player is now clear of all casino games; false means a departure is
// blocked mid-round and the caller (quit) must abort. Nil-safe for test
// scaffolding without a Casino manager.
func (g *Game) leaveCasinoGames(p *player.Player) bool {
	if g.Casino == nil {
		return true
	}
	if table, playing := g.Casino.Participation(p.Name); playing {
		if table != nil {
			g.emitCasinoEvents(g.Casino.Leave(table.RoomID, table.Config.ID, p.Name))
		} else if machine, ok := g.Casino.MachineFor(p.Name); ok {
			// Stop autobet first, then take the machine's own leave path: a
			// machine between spins has no committed stake, so one quit must
			// free it (and must not warn about a forfeit that cannot happen).
			// A machine mid-spin refuses the leave, the player stays seated,
			// and the caller warns about the stake that is really committed.
			if events, stopped := g.Casino.StopMachineAutoBet(machine.RoomID, machine.Config.ID, p.Name); stopped {
				g.emitCasinoEvents(events)
			}
			g.emitCasinoEvents(g.Casino.LeaveMachine(machine.RoomID, machine.Config.ID, p.Name))
		}
		_, stillPlaying := g.Casino.Participation(p.Name)
		return !stillPlaying
	}
	return true
}

// inCasinoGame reports whether the player is currently seated at any casino
// table or machine. Nil-safe for test scaffolding without a Casino manager.
func (g *Game) inCasinoGame(name string) bool {
	if g.Casino == nil {
		return false
	}
	_, playing := g.Casino.Participation(name)
	return playing
}

// casinoTable returns the room's table for the named game. A room addresses
// at most one table (or machine) per game name — "play blackjack" carries no
// table id — so a second table for the same game would be unreachable
// content; ValidateRoomConfigs rejects that configuration instead of silently
// dropping it.
func (g *Game) casinoTable(roomID int, gameName string) (*casino.Table, bool) {
	room, err := g.World.LoadRoom(roomID)
	if err != nil {
		return nil, false
	}
	if casino.ValidateRoomConfigs(room.CasinoTables, room.CasinoMachines) != nil {
		return nil, false
	}
	for _, cfg := range room.CasinoTables {
		if strings.EqualFold(string(cfg.Game), gameName) {
			table := g.Casino.EnsureTable(roomID, cfg)
			if table == nil {
				return nil, false
			}
			return table, true
		}
	}
	return nil, false
}

// casinoMachine returns the room's machine for the named game or variant.
// Like casinoTable, only the first match is reachable, which is why
// ValidateRoomConfigs rejects a room with two entries addressing the same
// game name or variant.
func (g *Game) casinoMachine(roomID int, gameName string) (*casino.Machine, bool) {
	room, err := g.World.LoadRoom(roomID)
	if err != nil {
		return nil, false
	}
	if casino.ValidateRoomConfigs(room.CasinoTables, room.CasinoMachines) != nil {
		return nil, false
	}
	for _, cfg := range room.CasinoMachines {
		if strings.EqualFold(string(cfg.Game), gameName) || strings.EqualFold(cfg.Variant, gameName) {
			machine := g.Casino.EnsureMachine(roomID, cfg)
			return machine, machine != nil
		}
	}
	// Migrate older room definitions that declared slots under casino_tables;
	// slots are still always instantiated as one-player machines.
	if strings.EqualFold(gameName, "slots") {
		for _, cfg := range room.CasinoTables {
			if strings.EqualFold(string(cfg.Game), "slots") {
				machine := g.Casino.EnsureMachine(roomID, casino.LegacySlotMachine(cfg))
				return machine, machine != nil
			}
		}
	}
	return nil, false
}

func (g *Game) executePlay(sess *net.Session, args []string, rawInput string) {
	p := sess.Player
	if p == nil || len(args) == 0 {
		sess.WriteLine("Play what?")
		return
	}
	if _, playing := g.Casino.Participation(p.Name); playing {
		sess.WriteLine("You're already playing a game. Type \"stop\" between rounds to leave it.")
		return
	}
	g.startCasinoGame(sess, p, args[0])
}

func (g *Game) startCasinoGame(sess *net.Session, p *player.Player, gameName string) {
	if p == nil || sess == nil {
		return
	}
	if _, playing := g.Casino.Participation(p.Name); playing {
		sess.WriteLine("You're already playing a game. Type \"stop\" between rounds to leave it.")
		return
	}
	if machine, ok := g.casinoMachine(p.RoomID, gameName); ok {
		g.emitCasinoEvents(g.Casino.JoinMachine(machine.RoomID, machine.Config, p.Name))
		return
	}
	table, ok := g.casinoTable(p.RoomID, gameName)
	if !ok {
		sess.WriteLine(fmt.Sprintf("There is no %s table here.", gameName))
		return
	}
	g.emitCasinoEvents(g.Casino.Join(table.RoomID, table.Config, p.Name))
}

func (g *Game) executeBet(sess *net.Session, args []string, rawInput string) {
	p := sess.Player
	if p == nil {
		sess.WriteLine("Bet how much?")
		return
	}
	if machine, ok := g.Casino.MachineFor(p.Name); ok {
		if len(args) == 0 {
			g.emitCasinoEvents(g.Casino.StartMachine(machine.RoomID, machine.Config.ID, p.Name, casinoWallet{g: g, p: p}))
			return
		}
		if len(args) == 1 {
			if args[0] == "max" {
				amount := min(machine.Config.MaxBet, casinoAffordable(p))
				if amount < 1 {
					sess.WriteLine("You don't have any chips or credits to bet.")
					return
				}
				g.emitCasinoEvents(g.Casino.SetMachineBet(machine.RoomID, machine.Config.ID, p.Name, amount, casinoWallet{g: g, p: p}))
				return
			}
			if amount, err := strconv.Atoi(args[0]); err == nil && amount > 0 {
				g.emitCasinoEvents(g.Casino.SetMachineBet(machine.RoomID, machine.Config.ID, p.Name, amount, casinoWallet{g: g, p: p}))
				return
			}
		}
		sess.WriteLine("Use bet, bet <amount>, or bet max.")
		return
	}
	table, playing := g.Casino.Participation(p.Name)
	if !playing || table == nil {
		sess.WriteLine("You're not playing a game.")
		return
	}
	// Table bet syntax: bet | bet <amount> [on] <target> | bet min|max [on] <target>.
	// BEFORE an "on" keyword, a token that parses as an amount (or min/max)
	// sets the wager and any other token is the bet target; AFTER "on", the
	// next token is always the target. That makes numeric targets reachable
	// ("bet 5 on 17"), which roulette, craps, and keno need.
	amount, spot, hasAmount, sawOn := 0, "", false, false
	for _, arg := range args {
		if strings.EqualFold(arg, "on") {
			sawOn = true
			continue
		}
		if !sawOn {
			if strings.EqualFold(arg, "min") {
				if hasAmount {
					sess.WriteLine("Use bet, bet <amount> [on <target>], bet min, or bet max.")
					return
				}
				amount, hasAmount = table.Config.MinBet, true
				continue
			}
			if strings.EqualFold(arg, "max") {
				if hasAmount {
					sess.WriteLine("Use bet, bet <amount> [on <target>], bet min, or bet max.")
					return
				}
				amount = min(table.Config.MaxBet, casinoAffordable(p))
				if amount < 1 {
					sess.WriteLine("You don't have any chips or credits to bet.")
					return
				}
				hasAmount = true
				continue
			}
			if value, err := strconv.Atoi(arg); err == nil && value > 0 {
				if hasAmount {
					sess.WriteLine("Use bet, bet <amount> [on <target>], bet min, or bet max.")
					return
				}
				amount, hasAmount = value, true
				continue
			}
		}
		if spot != "" {
			sess.WriteLine("Use bet, bet <amount> [on <target>], bet min, or bet max.")
			return
		}
		spot = strings.ToLower(arg)
	}
	if !hasAmount {
		var lastSpot string
		lastSpot, amount = g.Casino.Rebet(table.RoomID, table.Config.ID, p.Name)
		if spot == "" {
			spot = lastSpot
		}
		if amount <= 0 {
			sess.WriteLine("Bet how much?")
			return
		}
	}
	g.emitCasinoEvents(g.Casino.Bet(table.RoomID, table.Config.ID, p.Name, spot, amount, casinoWallet{g: g, p: p}))
}

func (g *Game) executeAutoBet(sess *net.Session, args []string, rawInput string) {
	p := sess.Player
	if p == nil {
		return
	}
	if machine, ok := g.Casino.MachineFor(p.Name); ok {
		g.emitCasinoEvents(g.Casino.EnableMachineAutoBet(machine.RoomID, machine.Config.ID, p.Name, casinoWallet{g: g, p: p}))
		return
	}
	sess.WriteLine("Autobet is only available at games without player choices.")
}

func (g *Game) executeTableAction(sess *net.Session, action string) {
	p := sess.Player
	if p == nil {
		return
	}
	table, playing := g.Casino.Participation(p.Name)
	if !playing || table == nil {
		sess.WriteLine("You're not playing a multiplayer casino game.")
		return
	}
	g.emitCasinoEvents(g.Casino.Action(table.RoomID, table.Config.ID, p.Name, action))
}

func (g *Game) CasinoTick() {
	if g.Casino != nil {
		g.emitCasinoEvents(g.Casino.Tick())
	}
}

func (g *Game) emitCasinoEvents(events []casino.Event) {
	for _, event := range events {
		if event.Message == "" && event.PrivateMessage == "" && event.Menu == nil && event.Snapshot == nil {
			continue
		}
		category := event.Color
		if category == "" {
			category = "casino_action"
		}
		if event.Public && g.Hub != nil {
			for _, sess := range g.Hub.PlayersInRoom(event.RoomID) {
				if event.PrivateTo != "" && sess.Player != nil && sess.Player.Name == event.PrivateTo {
					continue
				}
				message := event.Message
				if rendered := g.renderCasinoSnapshot(sess, event.Snapshot); rendered != "" {
					message += "\n" + rendered
				}
				sess.WriteLine(g.colorize(sess, category, message))
			}
		}
		if event.PrivateTo == "" {
			continue
		}
		text := event.PrivateMessage
		if text == "" {
			text = event.Message
		}
		if text == "" && event.Menu == nil {
			continue
		}
		g.charsMu.Lock()
		sess := g.loggedInChars[event.PrivateTo]
		g.charsMu.Unlock()
		if sess == nil {
			continue
		}
		privateMessage := g.casinoPrivateMessage(sess, category, event.Menu, text)
		if rendered := g.renderCasinoSnapshot(sess, event.Snapshot); rendered != "" {
			privateMessage += "\n" + rendered
		}
		sess.WriteLine(g.renderCasinoMessage(sess, category, event.Menu, privateMessage))
		if category == "casino_menu" {
			g.writePrompt(sess)
		}
	}
}

// renderCasinoMessage colorizes a casino message unless it is an
// already-composed structured menu.
func (g *Game) renderCasinoMessage(sess *net.Session, category string, menu *casino.MenuView, message string) string {
	if category == "casino_menu" && menu != nil {
		return message
	}
	return g.colorize(sess, category, message)
}

func (g *Game) casinoPrivateMessage(sess *net.Session, category string, menu *casino.MenuView, message string) string {
	if category != "casino_menu" || menu == nil {
		return message
	}
	balance := ""
	if menu.ShowBalance {
		chips := g.colorize(sess, "casino_chips", fmt.Sprintf("%d", countChips(sess.Player)))
		credits := g.colorize(sess, "casino_credits", fmt.Sprintf("%d", sess.Player.Credits))
		balance = fmt.Sprintf("You have %s chips and %s credits.", chips, credits)
	}
	heading := menu.Heading
	if heading == "" {
		heading = message
	}
	return g.renderCasinoCommands(sess, balance, heading, menu.Commands)
}

// renderCasinoSnapshot renders a game's structured view for one session. It is
// the only per-game switch in the presentation layer: adding a game means
// adding its snapshot type here, and the Snapshot interface guarantees the
// event carries it rather than being silently dropped by a field filter.
func (g *Game) renderCasinoSnapshot(sess *net.Session, snapshot casino.Snapshot) string {
	if snapshot == nil || sess.Player == nil {
		return ""
	}
	mode := g.colorMode(sess)
	unicode := sess.Player.OptionBool("unicode")
	switch s := snapshot.(type) {
	case *casino.SlotSnapshot:
		return renderSlotSnapshot(s, mode, unicode)
	case *casino.BlackjackSnapshot:
		return renderBlackjackSnapshot(s, mode, unicode, sess.Player.OptionInt("card_size"), sess.Player.OptionString("card_style"), g.CardArt)
	case *casino.BaccaratSnapshot:
		return renderBaccaratSnapshot(s, mode, unicode, sess.Player.OptionInt("card_size"), sess.Player.OptionString("card_style"), g.CardArt)
	}
	return ""
}

// renderCasinoCommands lays every casino menu out in the same style: an
// optional balance line, a heading, and an aligned command list with each
// command in the "command" color and its description in plain text.
func (g *Game) renderCasinoCommands(sess *net.Session, balance, heading string, commands []casino.MenuCommand) string {
	var sb strings.Builder
	if balance != "" {
		sb.WriteString(balance)
		sb.WriteString("\n\n")
	}
	if heading != "" {
		sb.WriteString(heading)
		sb.WriteString("\n\n")
	}
	width := 0
	for _, c := range commands {
		if n := utf8.RuneCountInString(c.Command); n > width {
			width = n
		}
	}
	for _, c := range commands {
		padded := c.Command + strings.Repeat(" ", width-utf8.RuneCountInString(c.Command))
		cmd := g.colorize(sess, "command", padded)
		if c.Desc != "" {
			fmt.Fprintf(&sb, "  %s  %s\n", cmd, c.Desc)
		} else {
			fmt.Fprintf(&sb, "  %s\n", cmd)
		}
	}
	return strings.TrimRight(sb.String(), "\n")
}

func renderBlackjackSnapshot(snapshot *casino.BlackjackSnapshot, mode string, unicode bool, size int, style string, art *cardart.Store) string {
	if snapshot == nil {
		return ""
	}
	size = cardRenderSize(unicode, size)
	var lines []string
	dealerTitle := "Dealer:"
	if snapshot.DealerRevealed {
		dealerTitle = "Dealer (" + snapshot.DealerScore + "):"
	} else if snapshot.DealerShownScore != "" {
		dealerTitle = "Dealer (" + snapshot.DealerShownScore + "):"
	}
	lines = append(lines, cardLine(mode, dealerTitle))
	lines = append(lines, cardsLine(mode, snapshot.Dealer, size, unicode, style, art)...)
	for _, player := range snapshot.Players {
		lines = append(lines, cardLine(mode, fmt.Sprintf("%s (%s):", player.Name, player.Score)))
		lines = append(lines, cardsLine(mode, player.Cards, size, unicode, style, art)...)
	}
	return strings.Join(lines, "\n")
}

// renderBaccaratSnapshot draws the player and banker hands followed by the
// list of wagers riding on the round.
func renderBaccaratSnapshot(snapshot *casino.BaccaratSnapshot, mode string, unicode bool, size int, style string, art *cardart.Store) string {
	if snapshot == nil {
		return ""
	}
	size = cardRenderSize(unicode, size)
	var lines []string
	lines = append(lines, cardLine(mode, "Player ("+snapshot.PlayerScore+"):"))
	lines = append(lines, cardsLine(mode, snapshot.Player, size, unicode, style, art)...)
	lines = append(lines, cardLine(mode, "Banker ("+snapshot.BankerScore+"):"))
	lines = append(lines, cardsLine(mode, snapshot.Banker, size, unicode, style, art)...)
	for _, bet := range snapshot.Bets {
		lines = append(lines, cardLine(mode, fmt.Sprintf("%s bets %d on %s.", bet.Name, bet.Amount, bet.Spot)))
	}
	return strings.Join(lines, "\n")
}

func cardLine(mode, text string) string {
	spec := color.NoColor()
	spec.Fg = 39
	return color.Render(mode, spec, text)
}

func cardsLine(mode string, cards []casino.CardView, size int, unicode bool, style string, art *cardart.Store) []string {
	if len(cards) == 0 {
		return nil
	}
	if size == 1 {
		parts := make([]string, len(cards))
		for i, card := range cards {
			parts[i] = colorizeCardSymbol(mode, card)
		}
		return []string{strings.Join(parts, " ")}
	}
	artLines := make([][]string, len(cards))
	for i, card := range cards {
		artLines[i] = cardArtLines(card, size, unicode, style, art)
	}
	lines := make([]string, size)
	for row := 0; row < size; row++ {
		var lineParts []string
		for i, card := range artLines {
			lineParts = append(lineParts, colorizeCardLine(mode, card[row], cards[i], row, size, style))
		}
		lines[row] = strings.Join(lineParts, " ")
	}
	return lines
}

func cardRenderSize(unicode bool, size int) int {
	if !unicode {
		return 5
	}
	if size == 1 || size == 5 || size == 7 || size == 9 {
		return size
	}
	return 7
}

var suitSymbols = map[string]string{"hearts": "♥", "spades": "♠", "diamonds": "♦", "clubs": "♣"}

func cardSymbol(card casino.CardView) string {
	if card.Hidden {
		return "?"
	}
	return card.Rank + suitSymbols[card.Suit]
}

func cardArtLines(card casino.CardView, size int, unicode bool, style string, art *cardart.Store) []string {
	if card.Hidden {
		return generatedCardArt("?", "", size, unicode, style)
	}
	key := card.Rank + strings.ToUpper(card.Suit[:1])
	if configured := art.Art(key, size); len(configured) == size {
		return configured
	}
	return generatedCardArt(card.Rank, card.Suit, size, unicode, style)
}

func generatedCardArt(rank, suit string, size int, unicode bool, style string) []string {
	if size < 5 {
		size = 5
	}
	border := "-"
	left, right := "+", "+"
	if unicode {
		border, left, right = "─", "┌", "┐"
	}
	bottomLeft, bottomRight := left, right
	if unicode {
		bottomLeft, bottomRight = "└", "┘"
	}
	vertical := "|"
	if unicode {
		vertical = "│"
	}
	if unicode && style == "light" {
		lines := []string{strings.Repeat("▄", size)}
		lines = append(lines, generatedCardBody(rank, suit, size, unicode, vertical)...)
		return append(lines, strings.Repeat("▀", size))
	}
	lines := []string{left + strings.Repeat(border, size-2) + right}
	lines = append(lines, generatedCardBody(rank, suit, size, unicode, vertical)...)
	lines = append(lines, bottomLeft+strings.Repeat(border, size-2)+bottomRight)
	return lines
}

func generatedCardBody(rank, suit string, size int, unicode bool, vertical string) []string {
	inner := size - 2
	lines := make([]string, 0, size-2)
	for row := 1; row < size-1; row++ {
		content := strings.Repeat(" ", inner)
		if row == 1 {
			content = rank + strings.Repeat(" ", inner-len(rank))
		}
		if row == (size-1)/2 {
			suitText := ""
			if suit != "" {
				suitText = suitLetter(suit, unicode)
			}
			suitWidth := utf8.RuneCountInString(suitText)
			leftPadding := (inner - suitWidth) / 2
			content = strings.Repeat(" ", leftPadding) + suitText + strings.Repeat(" ", inner-leftPadding-suitWidth)
		}
		if row == size-2 {
			content = strings.Repeat(" ", inner-len(rank)) + rank
		}
		lines = append(lines, vertical+content+vertical)
	}
	return lines
}

func suitLetter(suit string, unicode bool) string {
	if !unicode {
		return strings.ToUpper(suit[:1])
	}
	return suitSymbols[suit]
}

func colorizeCardLine(mode, line string, card casino.CardView, row, size int, style string) string {
	red := card.Suit == "hearts" || card.Suit == "diamonds"
	rankColor := 27
	if red {
		rankColor = 196
	}
	suitColor := 27
	if red {
		suitColor = 196
	}
	rankLine := row == 1 || row == size-2
	light := style == "light"
	bodyBackground := light && row > 0 && row < size-1
	var builder strings.Builder
	for _, r := range line {
		if strings.ContainsRune("┌─┐└┘│┬┴├┤┼╔╗╚╝═║╦╩╠╣╬▀▄+|-", r) {
			spec := color.ColorSpec{Fg: 15}
			if bodyBackground {
				spec.Bg = 15
			}
			builder.WriteString(color.Render(mode, spec, string(r)))
		} else if r == ' ' {
			if bodyBackground {
				builder.WriteString(color.Render(mode, color.ColorSpec{Fg: 15, Bg: 15}, " "))
			} else {
				builder.WriteRune(r)
			}
		} else {
			value := suitColor
			if rankLine {
				value = rankColor
			}
			spec := color.ColorSpec{Fg: value}
			if bodyBackground {
				spec.Bg = 15
			}
			builder.WriteString(color.Render(mode, spec, string(r)))
		}
	}
	return builder.String()
}

func colorizeCardSymbol(mode string, card casino.CardView) string {
	if card.Hidden {
		return color.Render(mode, color.ColorSpec{Fg: 15}, "?")
	}
	rankColor, suitColor := 27, 27
	if card.Suit == "hearts" || card.Suit == "diamonds" {
		rankColor, suitColor = 196, 196
	}
	runes := []rune(cardSymbol(card))
	rankLength := len([]rune(card.Rank))
	return color.Render(mode, color.ColorSpec{Fg: rankColor}, string(runes[:rankLength])) +
		color.Render(mode, color.ColorSpec{Fg: suitColor}, string(runes[rankLength:]))
}

func renderSlotSnapshot(snapshot *casino.SlotSnapshot, mode string, unicode bool) string {
	if snapshot == nil {
		return ""
	}
	left, junction, right, horizontal, vertical := '+', '+', '+', '-', '|'
	bottomLeft, bottomJunction, bottomRight := '+', '+', '+'
	if unicode {
		left, junction, right, horizontal, vertical = '\u250c', '\u252c', '\u2510', '\u2500', '\u2502'
		bottomLeft, bottomJunction, bottomRight = '\u2514', '\u2534', '\u2518'
	}
	separator := string(left)
	for reel := 0; reel < 5; reel++ {
		if reel > 0 {
			separator += string(junction)
		}
		separator += strings.Repeat(string(horizontal), 9)
	}
	separator += string(right)
	lines := []string{casinoFrame(mode, separator)}
	frameVertical := casinoFrame(mode, string(vertical))
	for row := 0; row < 3; row++ {
		line := frameVertical
		for reel := 0; reel < 5; reel++ {
			value := "..."
			if reel < snapshot.StoppedReels {
				value = snapshot.Grid[row][reel]
			}
			// Pad to the fixed 7-cell reel width; a malformed profile could
			// otherwise make this negative and panic. Validation caps the id
			// length, so this is a defence-in-depth backstop.
			pad := 7 - len(value)
			if pad < 0 {
				pad = 0
			}
			line += " " + colorSlotSymbol(mode, value) + strings.Repeat(" ", pad) + " " + frameVertical
		}
		lines = append(lines, line)
	}
	bottom := string(bottomLeft)
	for reel := 0; reel < 5; reel++ {
		if reel > 0 {
			bottom += string(bottomJunction)
		}
		bottom += strings.Repeat(string(horizontal), 9)
	}
	bottom += string(bottomRight)
	lines = append(lines, casinoFrame(mode, bottom))
	return strings.Join(lines, "\n")
}

func casinoFrame(mode, text string) string {
	spec := color.NoColor()
	spec.Fg = 244
	return color.Render(mode, spec, text)
}

func colorSlotSymbol(mode, symbol string) string {
	spec := color.NoColor()
	spec.Fg = 250
	switch symbol {
	case "straw":
		spec.Fg = 220
	case "stick":
		spec.Fg = 46
	case "brick":
		spec.Fg = 196
	case "hat":
		spec.Fg = 201
	case "wolf":
		spec.Fg = 39
	case "scatter":
		spec.Fg = 226
	default:
		spec.Dim = true
	}
	return color.Render(mode, spec, symbol)
}