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
	// Optional per-wallet persistence seam for fault-injection tests.
	saveCharacter func(*player.Player) error
}

// save treats a completed replacement as applied, even if its durability is
// uncertain. Reverting memory then would disagree with the visible file and
// could overwrite a paid win or resurrect a resolved stake on the next save.
// Report the storage fault, but do not tell the game to retry/refund an
// already-applied mutation. Only pre-replacement failures require rollback.
func (w casinoWallet) save(operation string) error {
	save := w.saveCharacter
	if save == nil {
		save = w.g.AccountStore.SaveCharacter
	}
	err := save(w.p)
	if errors.Is(err, persistence.ErrDurabilityUncertain) {
		fmt.Fprintf(os.Stderr, "casino %s: %s save durability uncertain: %v — keeping applied state\n", operation, w.p.Name, err)
		return nil
	}
	return err
}

// Wager debits the stake and records it in PendingWagers in the SAME atomic
// character save. The entry stays until the round resolves: a settlement
// removes the stakes it returns (PayCredits) or consumes them
// (ResolveStake/ResolveStakes), and startup refunds anything still listed
// (see recoverPendingWagers). A pre-replacement save failure reverts the
// debit and ledger entry; an uncertain replacement keeps both (see save).
func (w casinoWallet) Wager(amount int) (casino.Wager, error) {
	if amount <= 0 {
		return casino.Wager{}, casino.ErrInsufficientFunds
	}
	creditsBefore := w.p.Credits
	chips := countChips(w.p)
	if chips > amount {
		chips = amount
	}
	credits := amount - chips
	if creditsBefore < credits {
		return casino.Wager{}, casino.ErrInsufficientFunds
	}
	if chips > 0 {
		w.p.RemoveItem("chips", chips)
	}
	w.p.Credits -= credits
	pending := player.PendingWager{ID: newPendingWagerID(), Chips: chips, Credits: credits}
	w.p.PendingWagers = append(w.p.PendingWagers, pending)
	if err := w.save("wager"); err != 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 = creditsBefore
		removePendingWager(w.p, pending.ID)
		return casino.Wager{}, casino.ErrWalletPersistence
	}
	return casino.Wager{Total: amount, Chips: chips, Credits: credits, ID: pending.ID}, nil
}

// PayCredits banks a payout durably and, in the SAME save, resolves the
// listed stakes. stakeIDs may be empty for a payout that returns no stake (a
// free-spin bank already refunded by RefundOutstanding). A table settlement
// passes the hand's stake IDs so the credit and the stake return are one
// atomic step; a slot win passes its triggering stake for the same reason.
// Either way a crash can never pay the payout AND refund the same stake. A
// pre-replacement failure reverts both the credit and the ledger and reports
// failure. An uncertain replacement is applied and logged (see save).
func (w casinoWallet) PayCredits(amount int, stakeIDs ...string) error {
	return w.payCredits(amount, stakeIDs)
}

// payCredits credits the payout and, when stakeIDs is non-empty, removes
// those stakes from the pending ledger in the same atomic save. On a
// pre-replacement failure the credit and the ledger are reverted together.
func (w casinoWallet) payCredits(amount int, stakeIDs []string) error {
	if amount <= 0 && len(stakeIDs) == 0 {
		return nil
	}
	creditsBefore := w.p.Credits
	sum, capErr := addCreditsChecked(creditsBefore, amount)
	if capErr != nil {
		return capErr
	}
	var removed []player.PendingWager
	if len(stakeIDs) > 0 {
		removed = takePendingWagers(w.p, stakeIDs)
	}
	w.p.Credits = sum
	if err := w.save("payout"); err != nil {
		w.p.Credits = creditsBefore
		w.p.PendingWagers = append(w.p.PendingWagers, removed...)
		return casino.ErrWalletPersistence
	}
	return nil
}

// ResolveStake consumes ONE pending stake by wallet handle: its hand lost or
// was paid by a cover, so it must never be refunded. A settlement that
// already removed it (PayCredits) makes this a no-op, so no redundant
// save is paid.
func (w casinoWallet) ResolveStake(stakeID string) {
	if stakeID == "" {
		return
	}
	removed := takePendingWagers(w.p, []string{stakeID})
	if len(removed) == 0 {
		return
	}
	if err := w.save("resolve stake"); err != nil {
		// The durable file still lists the stake, so restore it in memory to
		// keep the two records consistent for a later retry/recovery.
		w.p.PendingWagers = append(w.p.PendingWagers, removed...)
		fmt.Fprintf(os.Stderr, "casino resolve stake: save for %s: %v (ledger restored in memory)\n", w.p.Name, err)
	}
}

// ResolveStakesByIDs consumes the listed pending stakes in one durable save.
// A losing split/doubled hand used to call ResolveStake once per handle, each
// with its own full character save; batching removes that repeated fsync and
// the crash window between saves.
func (w casinoWallet) ResolveStakesByIDs(stakeIDs ...string) {
	if len(stakeIDs) == 0 {
		return
	}
	removed := takePendingWagers(w.p, stakeIDs)
	if len(removed) == 0 {
		return
	}
	if err := w.save("resolve stakes"); err != nil {
		// The durable file still lists the stakes, so restore them in memory to
		// keep the two records consistent for a later retry/recovery.
		w.p.PendingWagers = append(w.p.PendingWagers, removed...)
		fmt.Fprintf(os.Stderr, "casino resolve stakes: save for %s: %v (ledger restored in memory)\n", w.p.Name, err)
	}
}

// RefundOutstanding returns every pending stake to the player — chips in
// kind, credits as credits — and clears the ledger in one save. It is used
// by graceful shutdown/eviction and by a pre-deal disconnect. A pre-replacement
// failure reverts the return and ledger for retry; an uncertain replacement
// keeps both applied (see save).
func (w casinoWallet) RefundOutstanding() (chips, credits int, err error) {
	before := append([]player.PendingWager(nil), w.p.PendingWagers...)
	for _, pending := range before {
		chips += pending.Chips
		credits += pending.Credits
	}
	if chips == 0 && credits == 0 {
		return 0, 0, nil
	}
	creditsBefore := w.p.Credits
	w.p.PendingWagers = nil
	if chips > 0 {
		if !w.g.giveChips(w.p, chips) {
			w.p.PendingWagers = before
			return 0, 0, casino.ErrWalletPersistence
		}
	}
	sum, capErr := addCreditsChecked(creditsBefore, credits)
	if capErr != nil {
		if chips > 0 {
			w.p.RemoveItem("chips", chips)
		}
		w.p.PendingWagers = before
		return 0, 0, casino.ErrWalletPersistence
	}
	w.p.Credits = sum
	if err := w.save("refund"); err != nil {
		w.p.Credits = creditsBefore
		if chips > 0 {
			w.p.RemoveItem("chips", chips)
		}
		w.p.PendingWagers = before
		return 0, 0, casino.ErrWalletPersistence
	}
	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 (cfg.Game == casino.GameVideoPoker && strings.EqualFold(cfg.ID, gameName)) || (cfg.Game != casino.GameVideoPoker && 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
	}
	// An explicit machine id is the most specific address, so match it first:
	// the shipped room's machine `huff_puff_01` must be reachable by name even
	// though it also declares a variant.
	for _, cfg := range room.CasinoMachines {
		if strings.EqualFold(cfg.ID, gameName) {
			machine := g.Casino.EnsureMachine(roomID, cfg)
			return machine, machine != nil
		}
	}
	// Prefer an exact variant match first: a room may host several variants of
	// one game, where a bare game name is ambiguous.
	for _, cfg := range room.CasinoMachines {
		if cfg.Variant != "" && strings.EqualFold(cfg.Variant, gameName) {
			machine := g.Casino.EnsureMachine(roomID, cfg)
			return machine, machine != nil
		}
	}
	// Then a bare game name: prefer a variant-less machine so a machine that
	// declares its own variant is reached by that variant, and a sole machine
	// of a game is still reachable by the game name.
	for _, cfg := range room.CasinoMachines {
		if cfg.Variant == "" && strings.EqualFold(string(cfg.Game), gameName) {
			machine := g.Casino.EnsureMachine(roomID, cfg)
			return machine, machine != nil
		}
	}
	for _, cfg := range room.CasinoMachines {
		if strings.EqualFold(string(cfg.Game), gameName) {
			machine := g.Casino.EnsureMachine(roomID, 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 {
		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
	}
	choices := g.casinoChoices(p.RoomID)
	input := ""
	if len(args) > 0 {
		input = args[0]
	}
	choice, ok := resolveCasinoChoice(choices, input)
	if !ok {
		g.showCasinoChoices(sess, choices)
		return
	}
	if len(args) > 1 {
		amount, err := strconv.Atoi(args[1])
		if !choice.table || len(args) > 3 || (args[1] != "min" && args[1] != "max" && (err != nil || amount <= 0)) {
			sess.WriteLine("Use play GAME [N|min|max] [on BET]. No wager was placed.")
			return
		}
	}
	g.startCasinoGame(sess, p, choice.address)
	if len(args) > 1 {
		if t, joined := g.Casino.Participation(p.Name); joined && t != nil {
			g.executeBet(sess, args[1:], rawInput)
		}
	}
}

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
	}
	events := g.Casino.Join(table.RoomID, table.Config, p.Name)
	if table.Config.Game == casino.GameVideoPoker {
		if joined, playing := g.Casino.Participation(p.Name); playing && joined == table {
			events = g.Casino.Bet(table.RoomID, table.Config.ID, p.Name, "view", 0, casinoWallet{g: g, p: p})
		}
	}
	g.emitCasinoEvents(events)
}

// Keep slots' spin-as-bet behavior, while Big 6 spins already committed wagers.
func (g *Game) executeSpin(sess *net.Session, args []string, rawInput string) {
	if sess.Player != nil {
		if table, playing := g.Casino.Participation(sess.Player.Name); playing && table != nil && table.Config.Game == casino.GameBigSix {
			if len(args) != 0 {
				sess.WriteLine("Use spin after placing your bets.")
				return
			}
			g.executeTableAction(sess, "spin")
			return
		}
	}
	g.executeBet(sess, args, rawInput)
}

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 N, or bet max.")
		return
	}
	table, playing := g.Casino.Participation(p.Name)
	if !playing || table == nil {
		sess.WriteLine("You're not playing a game.")
		return
	}
	if table.Config.Game == casino.GameVideoPoker {
		g.emitCasinoEvents(g.Casino.Action(table.RoomID, table.Config.ID, p.Name, strings.TrimSpace("coins "+strings.Join(args, " "))))
		return
	}
	// Baccarat repeats every remembered side bet and the main bet on a bare
	// "bet"; games with one wager keep the generic single-rebet path below.
	if table.Config.Game == casino.GameBaccarat && len(args) == 0 {
		g.emitCasinoEvents(g.Casino.RebetAll(table.RoomID, table.Config.ID, p.Name, casinoWallet{g: g, p: p}))
		return
	}
	// Table bet syntax: bet | bet N [on BET] | bet min|max [on BET].
	// 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.
	// Roulette combinations and craps bets need multi-token targets. Once
	// an amount and target keyword exist, subsequent numbers belong to the
	// target even without "on" (bet 10 split 1 2 / bet 10 buy 4).
	// Other games keep the stricter one-token target.
	joinTarget := table.Config.Game == casino.GameRoulette || table.Config.Game == casino.GameCraps
	amount, spot, hasAmount, sawOn := 0, "", false, false
	for i, arg := range args {
		if strings.EqualFold(arg, "on") {
			if sawOn || spot != "" || i == len(args)-1 {
				sess.WriteLine("Use bet N on BET. No wager was placed.")
				return
			}
			sawOn = true
			continue
		}
		// Once an amount is set, every remaining token belongs to the target
		// ("bet 2 2" and "bet 2 on 2" are identical). Before that, a numeric
		// token sets the amount and anything else starts the target.
		if !sawOn && !hasAmount {
			if strings.EqualFold(arg, "min") {
				amount, hasAmount = table.Config.MinBet, true
				continue
			}
			if strings.EqualFold(arg, "max") {
				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 {
				amount, hasAmount = value, true
				continue
			}
		}
		if spot == "" {
			spot = strings.ToLower(arg)
			continue
		}
		if joinTarget {
			spot += " " + strings.ToLower(arg)
			continue
		}
		sess.WriteLine("Use bet, bet N [on BET], bet min, or bet max.")
		return
	}
	if table.Config.Game == casino.GameBaccarat {
		switch spot {
		case "b":
			spot = "banker"
		case "p":
			spot = "player"
		case "t":
			spot = "tie"
		}
	}
	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
	}
	if table.Config.Game == casino.GameVideoPoker && action == "deal" {
		g.emitCasinoEvents(g.Casino.Bet(table.RoomID, table.Config.ID, p.Name, "deal", 0, casinoWallet{g: g, p: p}))
		return
	}
	g.emitCasinoEvents(g.Casino.Action(table.RoomID, table.Config.ID, p.Name, action))
}

// Keep the automatic post-command prompt out of a seated player's spin
// animation. Settlement menus resume prompting once the table leaves playing.
func (g *Game) rouletteSpinning(sess *net.Session) bool {
	if g.Casino == nil || sess == nil || sess.Player == nil {
		return false
	}
	table, playing := g.Casino.Participation(sess.Player.Name)
	if !playing || table == nil {
		return false
	}
	if table.Config.Game == casino.GameBigSix {
		return table.Busy(sess.Player.Name)
	}
	if table.Config.Game != casino.GameRoulette {
		return false
	}
	s, ok := table.Board(sess.Player.Name).(*casino.RouletteSnapshot)
	return ok && s.Phase == "playing"
}

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 && len(event.Settlement) == 0 {
			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
				}
				details := g.seesCasinoDetails(sess, event)
				if event.Detail && !details {
					continue
				}
				// Style prose before composing it with independently styled art.
				// Wrapping the finished message leaks casino_action into borders
				// and plain spaces between a snapshot's own color resets.
				message := g.casinoProse(sess, category, g.casinoTimeText(event.Message))
				if details {
					if rendered := g.renderCasinoSnapshot(sess, event.Snapshot); rendered != "" {
						if message != "" {
							message += "\n"
						}
						message += rendered
					}
				}
				if message != "" {
					sess.WriteLine(message)
				}
			}
		}
		if event.PrivateTo == "" {
			continue
		}
		text := event.PrivateMessage
		if text == "" {
			text = event.Message
		}
		if text == "" && event.Menu == nil && event.Snapshot == nil && len(event.Settlement) == 0 {
			continue
		}
		g.charsMu.Lock()
		sess := g.loggedInChars[event.PrivateTo]
		g.charsMu.Unlock()
		if sess == nil {
			continue
		}
		privateMessage := g.casinoPrivateMessage(sess, category, event.Menu, g.casinoTimeText(text))
		privateMessage = g.renderCasinoMessage(sess, category, event.Menu, privateMessage)
		rendered := g.renderCasinoSnapshot(sess, event.Snapshot)
		if len(event.Settlement) > 0 {
			receipt := renderCasinoSettlement(event.Settlement, sess.Player.OptionBool("unicode"), func(tag, text string) string { return g.colorize(sess, tag, text) })
			if event.SettlementNote != "" {
				receipt += "\n" + g.casinoProse(sess, "casino_warning", event.SettlementNote)
			}
			// Reveal first, then the receipt, then the next-action menu. A
			// settlement's legacy prose is only a non-UI fallback, not a second payout.
			rendered = composeTableThenReminder(rendered, receipt)
			if event.Menu == nil {
				privateMessage = ""
			}
		}
		if reminder, ok := g.casinoBoardReminder(sess, category, event.Menu, event.Snapshot, g.casinoTimeText(text)); ok {
			privateMessage = composeTableThenReminder(rendered, reminder)
		} else if rendered != "" {
			if privateMessage != "" {
				privateMessage += "\n"
			}
			privateMessage += rendered
		}
		if event.ShowBalance {
			privateMessage += "\n" + g.casinoBalance(sess)
		}
		sess.WriteLine(privateMessage)
		if category == "casino_menu" {
			g.writePrompt(sess)
		}
	}
}

// casinoMenuParts resolves a structured menu into the shared header/balance
// heading/commands used by both menu render paths: the balance line, the
// heading (falling back to the event message), and a copy of the commands
// annotated with an unavailability note for anything the player can't afford.
func (g *Game) casinoMenuParts(sess *net.Session, menu *casino.MenuView, message string) (balance, heading string, commands []casino.MenuCommand) {
	balance = ""
	if menu.ShowBalance {
		balance = g.casinoBalance(sess)
	}
	heading = g.casinoTimeText(menu.Heading)
	if heading == "" {
		heading = message
	}
	commands = append([]casino.MenuCommand(nil), menu.Commands...)
	if !g.casinoHintsVisible(sess, menu) {
		commands = nil
	}
	for i := range commands {
		if commands[i].Cost > casinoAffordable(sess.Player) {
			commands[i].Desc += " [unavailable: insufficient funds]"
		}
	}
	return balance, heading, commands
}

// casinoHintsVisible decides whether a menu's command list prints. "on"
// always shows hints (the historical behavior); "off" never does; the default
// "once" shows them only on the menu a player gets when sitting down. Players
// can always ask for the live list with "what" or "verbs".
func (g *Game) casinoHintsVisible(sess *net.Session, menu *casino.MenuView) bool {
	if sess == nil || sess.Player == nil || menu == nil {
		return true
	}
	switch sess.Player.OptionString("casino_hints") {
	case "off":
		return false
	case "once":
		return menu.ShowHints
	default:
		return true
	}
}

// casinoBoardReminder splits a persistent-board menu (craps, roulette, Big 6,
// video poker, Pai Gow) so its instructions print under the board they describe.
// Every other game, and compact displays, keep their menu in one block.
func (g *Game) casinoBoardReminder(sess *net.Session, category string, menu *casino.MenuView, snapshot casino.Snapshot, message string) (reminder string, ok bool) {
	if category != "casino_menu" || menu == nil || sess.Player == nil {
		return "", false
	}
	_, isCraps := snapshot.(*casino.CrapsSnapshot)
	_, isPoker := snapshot.(*casino.VideoPokerSnapshot)
	_, isPlinko := snapshot.(*casino.PlinkoSnapshot)
	_, isPaiGow := snapshot.(*casino.PaiGowSnapshot)
	b, isBigSix := snapshot.(*casino.BigSixSnapshot)
	isBigSix = isBigSix && b.Phase != "playing" && b.Phase != "result"
	s, isRoulette := snapshot.(*casino.RouletteSnapshot)
	if !isPlinko && !isPoker && !isCraps && !isPaiGow && !isBigSix && (!isRoulette || s.Phase == "playing" || s.Phase == "result") {
		return "", false
	}
	if !isPlinko && !isPoker && !isCraps && !isPaiGow && !isBigSix && sess.Player.OptionString("casino_display") == "compact" && (menu.Repeat || !menu.ShowBalance) {
		// The compact reminder is already a short block; leave it intact.
		return "", false
	}
	balance, heading, commands := g.casinoMenuParts(sess, menu, message)
	// The board replaces the game-name heading, and the balance sits with the
	// commands underneath it rather than above the graphic.
	return g.renderCasinoCommands(sess, balance, heading, commands), true
}

// composeTableThenReminder joins a board graphic and the wager reminder. The
// board snapshot already leads with a blank line, and the reminder keeps
// exactly one blank line below the board's last visible row.
func composeTableThenReminder(table, reminder string) string {
	out := strings.TrimRight(table, "\n")
	if reminder != "" {
		if out != "" {
			out += "\n\n"
		}
		out += reminder
	}
	return out
}

// 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 message == "" {
		return ""
	}
	if category == "casino_menu" && menu != nil {
		return message
	}
	return g.casinoProse(sess, category, message)
}

// casinoProse colorizes casino event text, expanding inline color tags such as
// {casino_result_win}WIN{/} against the session's palette. The event's color
// category is the default for untagged text.
func (g *Game) casinoProse(sess *net.Session, category, text string) string {
	return g.expandTagsDefault(sess, g.resolveColor(sess, category), text)
}

func (g *Game) casinoPrivateMessage(sess *net.Session, category string, menu *casino.MenuView, message string) string {
	if category != "casino_menu" || menu == nil {
		return message
	}
	balance, heading, commands := g.casinoMenuParts(sess, menu, message)
	if sess.Player.OptionString("casino_display") == "compact" && !menu.ShowBalance {
		var hints []casino.MenuCommand
		for _, c := range commands {
			label := c.Command
			switch c.Command {
			case "hit":
				label = "h:hit"
			case "stand":
				label = "st:stand"
			case "double":
				label = "dd:double"
			case "split":
				label = "sp:split"
			}
			if c.Cost > 0 {
				label += fmt.Sprintf(" (+%d)", c.Cost)
			}
			hints = append(hints, casino.MenuCommand{Command: label, Cost: c.Cost})
		}
		return g.renderCasinoCommands(sess, balance, heading, hints)
	}
	return g.renderCasinoCommands(sess, balance, heading, 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")
	// Card art is governed by card_size alone; casino_display only controls
	// how verbose the command menus are.
	size := sess.Player.OptionInt("card_size")
	switch s := snapshot.(type) {
	case *casino.PlinkoSnapshot:
		return renderPlinko(s, mode, unicode)
	case *casino.PaiGowSnapshot:
		return renderPaiGow(s, mode, unicode, size, sess.Player.OptionString("card_style"), g.CardArt)
	case *casino.VideoPokerSnapshot:
		return renderVideoPoker(s, mode, unicode, size, sess.Player.OptionString("card_style"), g.CardArt)
	case *casino.CrapsSnapshot:
		return renderCrapsSnapshot(s, mode, unicode, sess.Player.OptionString("card_style"))
	case *casino.BigSixSnapshot:
		return renderBigSixSnapshot(s, mode, unicode)
	case *casino.RouletteSnapshot:
		return renderRouletteSnapshot(s, mode, unicode, size)
	case *casino.SlotSnapshot:
		return renderSlotSnapshot(s, mode, unicode)
	case *casino.BlackjackSnapshot:
		return renderBlackjackSnapshotFor(s, mode, unicode, size, sess.Player.OptionString("card_style"), g.CardArt, sess.Player.Name)
	case *casino.BlackjackRulesView:
		return renderBlackjackRulesFelt(s.Config, mode, unicode)
	case *casino.BaccaratRulesView:
		return renderBaccaratRulesFelt(s.Config, mode, unicode)
	case *casino.BaccaratSnapshot:
		return renderBaccaratSnapshot(s, mode, unicode, 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 {
	head := g.casinoMenuHeader(sess, balance, heading)
	body := g.casinoMenuCommands(sess, commands)
	switch {
	case head == "":
		return body
	case body == "":
		return head
	default:
		return head + "\n\n" + body
	}
}

// casinoMenuHeader formats the balance and heading that introduce a casino
// menu. The heading (if any) comes first so the balance always sits directly
// above the command list. It is split from the command list so the roulette
// board can be drawn between them.
func (g *Game) casinoMenuHeader(sess *net.Session, balance, heading string) string {
	var sb strings.Builder
	if heading != "" {
		sb.WriteString(g.colorize(sess, "casino_action", heading))
		sb.WriteString("\n\n")
	}
	if balance != "" {
		sb.WriteString(balance)
		sb.WriteString("\n\n")
	}
	return strings.TrimRight(sb.String(), "\n")
}

// casinoMenuCommands formats an aligned, colored command list.
func (g *Game) casinoMenuCommands(sess *net.Session, commands []casino.MenuCommand) string {
	return g.casinoCommandColumns(sess, commands)
}

func renderBlackjackSnapshotFor(snapshot *casino.BlackjackSnapshot, mode string, unicode bool, size int, style string, art *cardart.Store, viewer string) 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 + "):"
	}
	if size == 1 {
		lines = append(lines, cardLine(mode, dealerTitle)+"  "+strings.Join(cardsLine(mode, snapshot.Dealer, size, unicode, style, art), " "))
	} else {
		lines = append(lines, cardLine(mode, dealerTitle))
		lines = append(lines, cardsLine(mode, snapshot.Dealer, size, unicode, style, art)...)
	}
	for _, player := range snapshot.Players {
		name := player.Name
		if name == viewer {
			name = "You"
		}
		marker := "  "
		if player.Active {
			marker = "> "
		}
		detail := ""
		if player.Hand > 0 {
			detail = fmt.Sprintf(" | Hand %d/%d | Wager %d | %s", player.Hand, player.Hands, player.Bet, player.Status)
		}
		if player.Active && player.Name != viewer {
			detail = strings.ReplaceAll(detail, "Your turn", "Playing")
		}
		title := fmt.Sprintf("%s%s (%s)%s:", marker, name, player.Score, detail)
		if size == 1 {
			lines = append(lines, cardLine(mode, title)+"  "+strings.Join(cardsLine(mode, player.Cards, size, unicode, style, art), " "))
		} else {
			lines = append(lines, cardLine(mode, title))
			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
	if size == 1 {
		lines = append(lines, cardLine(mode, "Player ("+snapshot.PlayerScore+"):")+"  "+strings.Join(cardsLine(mode, snapshot.Player, size, unicode, style, art), " "), cardLine(mode, "Banker ("+snapshot.BankerScore+"):")+"  "+strings.Join(cardsLine(mode, snapshot.Banker, size, unicode, style, art), " "))
	} else {
		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 {
			if !unicode {
				if card.Hidden {
					parts[i] = "[??]"
				} else {
					suit := map[string]string{"hearts": "H", "diamonds": "D", "spades": "S", "clubs": "C"}[card.Suit]
					parts[i] = card.Rank + suit
				}
			} else {
				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
}

// renderCardRow lays cards side by side, each column padded to its own art
// or label width, and appends an optional centered label row. minWidth lets
// the caller force a floor (video poker's HELD labels need it) while Pai Gow
// passes 0. It is the shared "cards with numbers underneath" presentation.
func renderCardRow(cards []casino.CardView, labels []string, minWidth int, mode string, unicode bool, size int, style string, art *cardart.Store) []string {
	if len(cards) == 0 {
		return nil
	}
	artLines := make([][]string, len(cards))
	widths := make([]int, len(cards))
	height := 0
	for i, card := range cards {
		artLines[i] = cardsLine(mode, []casino.CardView{card}, size, unicode, style, art)
		height = max(height, len(artLines[i]))
		widths[i] = minWidth
		for _, line := range artLines[i] {
			widths[i] = max(widths[i], color.VisibleLen(line))
		}
		if i < len(labels) {
			widths[i] = max(widths[i], color.VisibleLen(labels[i]))
		}
	}
	lines := make([]string, 0, height+1)
	for row := 0; row < height; row++ {
		parts := make([]string, len(cards))
		for i := range cards {
			text := ""
			if row < len(artLines[i]) {
				text = artLines[i][row]
			}
			parts[i] = rouletteCenter(text, widths[i])
		}
		lines = append(lines, strings.Join(parts, " "))
	}
	if len(labels) > 0 {
		parts := make([]string, len(cards))
		for i := range cards {
			text := ""
			if i < len(labels) {
				text = labels[i]
			}
			parts[i] = rouletteCenter(text, widths[i])
		}
		lines = append(lines, strings.Join(parts, " "))
	}
	return lines
}

func cardRenderSize(unicode bool, size int) int {
	if size == 1 {
		return 1
	}
	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": "♣", "joker": "★"}

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
	if card.Rank == "JK" {
		return jokerCardArt(size, unicode, style, art)
	}
	if card.Suit != "" {
		key += strings.ToUpper(card.Suit[:1])
	}
	if configured := art.Art(key, size); len(configured) == size {
		if unicode && style == "light" {
			// The shared pip art draws a dark box frame, which leaves the top
			// and bottom rows looking like the dark style. Replace only those
			// two rows with the half-block edges the white body meets.
			configured = append([]string(nil), configured...)
			configured[0] = strings.Repeat("▄", utf8.RuneCountInString(configured[0]))
			configured[size-1] = strings.Repeat("▀", utf8.RuneCountInString(configured[size-1]))
		}
		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)
}