feat: cryptocurrency exchange added to casino

11 files changed, 1324 insertions, 6 deletions

diff --git a/internal/game/cmd_bank.go b/internal/game/cmd_bank.go
index deddf0b..15ce85f 100644
--- a/internal/game/cmd_bank.go
+++ b/internal/game/cmd_bank.go
@@ -102,6 +102,9 @@ func (g *Game) showBankBrowse(sess *net.Session) {
 		entries = append(entries, bankEntry{slot: i, pos: len(entries) + 1, name: itemName, id: slot.ItemID, qty: slot.Quantity})
 	}
 
+	if p.Crypto.Balance < 0 {
+		sess.WriteLine(g.colorize(sess, "casino_result_loss", fmt.Sprintf("Crypto Exchange debt: %d credits. Future credit deposits repay this first.", -p.Crypto.Balance)))
+	}
 	if len(entries) == 0 && p.BankedCredits <= 0 {
 		sess.WriteLine("Your bank is empty.")
 		return
@@ -372,13 +375,26 @@ func (g *Game) doBankDepositCredits(sess *net.Session, parts []string) {
 		sess.WriteLine("You don't have that many credits.")
 		return
 	}
-	creditsBefore, bankedBefore := p.Credits, p.BankedCredits
-	p.Credits -= amount
-	p.BankedCredits += amount
-	if !g.persistBankCredits(p, creditsBefore, bankedBefore) {
+	var seized int64
+	if err := g.cryptoTransaction(p, func() error {
+		// Seize from the incoming deposit before the bank cap check. This also
+		// permits repayment when the bank itself is already at the balance cap.
+		seized = min(int64(amount), max(int64(0), -p.Crypto.Balance))
+		bank, err := addCreditsChecked(p.BankedCredits, amount-int(seized))
+		if err != nil {
+			return err
+		}
+		p.Credits -= amount
+		p.BankedCredits = bank
+		p.Crypto.Balance += seized
+		return nil
+	}); err != nil {
 		sess.WriteLine("The bank terminal could not record the transfer; nothing was moved.")
 		return
 	}
+	if seized > 0 {
+		sess.WriteLine(fmt.Sprintf("The Crypto Exchange seized %d deposited credits to repay debt.", seized))
+	}
 	sess.WriteLine(g.colorize(sess, "currency_pickup", fmt.Sprintf("You deposit %s credits. (Banked: %s)", formatInt(amount), formatInt(p.BankedCredits))))
 	g.showBankBrowse(sess)
 }
@@ -394,6 +410,10 @@ func (g *Game) doBankWithdrawCredits(sess *net.Session, parts []string) {
 		sess.WriteLine("Invalid amount.")
 		return
 	}
+	if p.Crypto.Balance < 0 {
+		sess.WriteLine("Your bank credits are subject to Crypto Exchange debt. Repay the debt before withdrawing.")
+		return
+	}
 	if p.BankedCredits < amount {
 		sess.WriteLine("You don't have that many banked credits.")
 		return
@@ -421,7 +441,7 @@ func (g *Game) doBankWithdrawCredits(sess *net.Session, parts []string) {
 // a wager taken from that phantom balance would be charged against money the
 // player does not durably have. Reports whether the move may be announced.
 func (g *Game) persistBankCredits(p *player.Player, creditsBefore, bankedBefore int) bool {
-	if err := g.AccountStore.SaveCharacter(p); err != nil {
+	if err := (casinoWallet{g: g, p: p}).save("bank credit transfer"); err != nil {
 		log.Printf("bank credit transfer %s: %v", p.Name, err)
 		p.Credits = creditsBefore
 		p.BankedCredits = bankedBefore
diff --git a/internal/game/cmd_look.go b/internal/game/cmd_look.go
index ab01c4c..92aeea6 100644
--- a/internal/game/cmd_look.go
+++ b/internal/game/cmd_look.go
@@ -65,6 +65,15 @@ func (g *Game) doLook(sess *net.Session) {
 	// Seated at a table: look keeps its room-first order, then appends the
 	// live game state and the current hint menu.
 	g.showCasinoGameLook(sess, p, room)
+	if sess.CryptoActive && room.CryptoExchange {
+		sess.CryptoShowHints = true
+		if sess.CryptoBusy {
+			sess.WriteLine("Updating crypto quotes...")
+			g.cryptoHints(sess)
+		} else {
+			g.executeCrypto(sess, "refresh", nil)
+		}
+	}
 	if sess.PredictionActive && room.PredictionExchange {
 		sess.WriteLine("")
 		if sess.PredictionBusy {
diff --git a/internal/game/cmd_registry.go b/internal/game/cmd_registry.go
index abc1539..d10ba0e 100644
--- a/internal/game/cmd_registry.go
+++ b/internal/game/cmd_registry.go
@@ -398,6 +398,9 @@ func (g *Game) executeCommand(sess *net.Session, cmd string, args []string, rawI
 		}
 	}
 
+	if g.handleCryptoInput(sess, cmd, args) {
+		return
+	}
 	if g.handlePredictionInput(sess, cmd, args) {
 		return
 	}
diff --git a/internal/game/cmd_use.go b/internal/game/cmd_use.go
index 54a36f5..af60204 100644
--- a/internal/game/cmd_use.go
+++ b/internal/game/cmd_use.go
@@ -31,6 +31,10 @@ func (g *Game) doUse(sess *net.Session, input string) {
 
 	lower := strings.ToLower(strings.TrimSpace(input))
 
+	if cryptoUseTarget(lower) && g.atCryptoCounter(p) {
+		g.openCryptoCounter(sess)
+		return
+	}
 	if predictionUseTarget(lower) && g.atPredictionCounter(p) {
 		g.openPredictionCounter(sess)
 		return
diff --git a/internal/game/cmd_verbs.go b/internal/game/cmd_verbs.go
index 87e8ee0..b5b0c3d 100644
--- a/internal/game/cmd_verbs.go
+++ b/internal/game/cmd_verbs.go
@@ -191,6 +191,10 @@ func (g *Game) collectRoomCommands(sess *net.Session) roomCommandSections {
 
 func (g *Game) executeVerbs(sess *net.Session, args []string, rawInput string) {
 	p := sess.Player
+	if sess.CryptoActive && g.atCryptoCounter(p) {
+		g.showCasinoHints(sess, g.cryptoCommands(sess))
+		return
+	}
 	if sess.PredictionActive && g.atPredictionCounter(p) {
 		g.showCasinoHints(sess, g.predictionCommands(sess))
 		return
diff --git a/internal/game/crypto.go b/internal/game/crypto.go
new file mode 100644
index 0000000..08a6b64
--- /dev/null
+++ b/internal/game/crypto.go
@@ -0,0 +1,681 @@
+package game
+
+import (
+	"context"
+	"fmt"
+	"sort"
+	"strconv"
+	"strings"
+	"time"
+
+	"thehouseoficarus/internal/cryptomarket"
+	"thehouseoficarus/internal/net"
+	"thehouseoficarus/internal/player"
+)
+
+func cryptoUseTarget(s string) bool {
+	switch s {
+	case "crypto", "cryptocurrency", "crypto exchange":
+		return true
+	}
+	return false
+}
+func (g *Game) atCryptoCounter(p *player.Player) bool {
+	if p == nil || g.World == nil {
+		return false
+	}
+	r, e := g.World.LoadRoom(p.RoomID)
+	return e == nil && r.CryptoExchange
+}
+func (g *Game) openCryptoCounter(s *net.Session) {
+	if !g.atCryptoCounter(s.Player) {
+		s.WriteLine("There is no Crypto Exchange here.")
+		return
+	}
+	if s.CryptoActive {
+		s.CryptoShowHints = true
+		g.executeCrypto(s, "refresh", nil)
+		return
+	}
+	if !g.leaveCasinoGames(s.Player) {
+		s.WriteLine("Finish your casino round first.")
+		return
+	}
+	g.closePredictionCounter(s)
+	g.closeCryptoCounter(s)
+	s.CryptoActive = true
+	s.CryptoShowHints = true
+	g.executeCrypto(s, "markets", nil)
+}
+func (g *Game) closeCryptoCounter(s *net.Session) {
+	if s.CryptoCancel != nil {
+		s.CryptoCancel()
+		s.CryptoCancel = nil
+	}
+	s.CryptoActive = false
+	s.CryptoBusy = false
+	s.CryptoEpoch++
+	s.CryptoSelected = ""
+	s.CryptoScreen = "markets"
+	s.CryptoShowHints = false
+	s.CryptoUnavailable = false
+}
+
+// cryptoVerbs is the counter's own vocabulary. Exact matches win, and unique
+// prefixes are accepted just like every other casino and counter interface.
+// Real world commands keep their meaning unless the counter explicitly owns
+// them (buy, sell, option, close, rules and help are claimed on the counter).
+var cryptoVerbs = []string{
+	"markets", "view", "buy", "sell", "short", "cover", "option", "write",
+	"quote", "contracts", "close", "active", "portfolio", "closed", "fund",
+	"withdraw", "repay", "refresh", "back", "help", "rules", "stop", "leave", "exit",
+}
+
+func cryptoVerb(cmd string) (string, bool) {
+	for _, v := range cryptoVerbs {
+		if cmd == v {
+			return v, true
+		}
+	}
+	if _, exists := commandRegistry[cmd]; exists {
+		return "", false
+	}
+	found := ""
+	for _, v := range cryptoVerbs {
+		if strings.HasPrefix(v, cmd) {
+			if found != "" {
+				return "", true
+			}
+			found = v
+		}
+	}
+	return found, found != ""
+}
+func (g *Game) cryptoInputOwned(s *net.Session, cmd string) bool {
+	if !s.CryptoActive || !g.atCryptoCounter(s.Player) {
+		return false
+	}
+	_, ok := cryptoVerb(cmd)
+	return ok
+}
+func (g *Game) handleCryptoInput(s *net.Session, cmd string, args []string) bool {
+	if !s.CryptoActive {
+		return false
+	}
+	if !g.atCryptoCounter(s.Player) {
+		g.closeCryptoCounter(s)
+		return false
+	}
+	if cmd == "help" && len(args) > 0 {
+		return false
+	}
+	verb, owned := cryptoVerb(cmd)
+	if !owned {
+		if cmd == "use" && cryptoUseTarget(strings.ToLower(strings.Join(args, " "))) {
+			return false
+		}
+		switch cmd {
+		case "use", "play", "bank", "quit", "logout":
+			g.closeCryptoCounter(s)
+		}
+		return false
+	}
+	if verb == "" {
+		s.WriteLine("That shortcut is ambiguous. Choose a command below.")
+		g.cryptoHints(s)
+		return true
+	}
+	// Keep the global option/options settings command reachable: only a
+	// real option trade (option call|put ...) belongs to the counter. The
+	// plural options command is the player's settings command, not ours.
+	if verb == "option" && !(len(args) > 0 && (args[0] == "call" || args[0] == "put")) {
+		return false
+	}
+	switch verb {
+	case "stop", "leave", "exit":
+		g.closeCryptoCounter(s)
+		s.WriteLine("You step away from the Crypto Exchange. Your positions stay open.")
+	case "help", "rules":
+		g.cryptoHelp(s)
+	default:
+		g.executeCrypto(s, verb, args)
+	}
+	return true
+}
+func (g *Game) cryptoHelp(s *net.Session) {
+	g.predictionFrame(s, "HOW TO TRADE", []string{
+		"Fund your account, choose a currency, then buy coins or back a falling price with a short.",
+		"Try: fund 1000, view BTC, buy BTC 0.001. Sell a position with close ID.",
+		"Options let you bet on a price by a future date. Use quote to check the price first.",
+		"Shorts and written options can leave debts. The exchange collects these from your bank and future deposits.",
+		"Your positions are checked when you return, not while you are away. See help crypto for details.",
+	})
+	g.cryptoHints(s, true)
+}
+
+// A transaction snapshots only the fields it owns. Money and ledger always
+// share one atomic save, including bank garnishment; uncertain renames remain
+// applied using the existing casino persistence contract.
+func (g *Game) cryptoTransaction(p *player.Player, mutate func() error) error {
+	before := p.Crypto.Clone()
+	credits, bank := p.Credits, p.BankedCredits
+	rollback := func() { p.Crypto = before; p.Credits = credits; p.BankedCredits = bank }
+	if e := p.Crypto.Validate(); e != nil {
+		return e
+	}
+	if e := mutate(); e != nil {
+		rollback()
+		return e
+	}
+	p.Crypto.SweepBank(&p.BankedCredits)
+	if e := p.Crypto.Validate(); e != nil {
+		rollback()
+		return e
+	}
+	if e := (casinoWallet{g: g, p: p}).save("crypto exchange"); e != nil {
+		rollback()
+		return fmt.Errorf("exchange could not save; balances unchanged: %w", e)
+	}
+	return nil
+}
+func (g *Game) reconcileCrypto(p *player.Player, snap cryptomarket.Snapshot, now time.Time) ([]string, error) {
+	work := p.Crypto.Clone()
+	messages, e := work.Reconcile(snap, now)
+	if e != nil {
+		return nil, e
+	}
+	bank := p.BankedCredits
+	paid := work.SweepBank(&bank)
+	if len(messages) == 0 && paid == 0 {
+		return nil, nil
+	}
+	e = g.cryptoTransaction(p, func() error { p.Crypto = work; p.BankedCredits = bank; return nil })
+	if e != nil {
+		return nil, e
+	}
+	if paid > 0 {
+		messages = append(messages, fmt.Sprintf("The Crypto Exchange collected %d bank credits against debt.", paid))
+	}
+	return messages, nil
+}
+func (g *Game) cryptoFunds(s *net.Session, action string, args []string, verified ...cryptomarket.Snapshot) {
+	if len(args) != 1 {
+		s.WriteLine(action + " CREDITS")
+		return
+	}
+	n, e := strconv.ParseInt(args[0], 10, 64)
+	if e != nil || n <= 0 || n > cryptomarket.MaxMoney {
+		s.WriteLine("Enter a positive whole-credit amount within the economy limit.")
+		return
+	}
+	p := s.Player
+	e = g.cryptoTransaction(p, func() error {
+		p.Crypto.SweepBank(&p.BankedCredits)
+		switch action {
+		case "fund", "repay":
+			if action == "repay" && (p.Crypto.Balance >= 0 || n > -p.Crypto.Balance) {
+				return fmt.Errorf("repay at most the outstanding exchange debt")
+			}
+			if int64(p.Credits) < n {
+				return fmt.Errorf("not enough carried credits")
+			}
+			balance, err := cryptomarket.Sum(p.Crypto.Balance, n)
+			if err != nil {
+				return err
+			}
+			p.Credits -= int(n)
+			p.Crypto.Balance = balance
+		case "withdraw":
+			if p.Crypto.Balance < n {
+				return fmt.Errorf("not enough available exchange cash")
+			}
+			// Only withdraw free cash, never collateral. Derivatives must have
+			// verified nonnegative close equity, even when a positive settlement
+			// is waiting for balance-cap room. Missing data cannot release cash.
+			for _, v := range p.Crypto.Positions {
+				if v.Status != "open" || (!v.Risky() && !v.Option()) {
+					continue
+				}
+				if len(verified) != 1 {
+					return fmt.Errorf("derivatives need current quotes before withdrawing")
+				}
+				expiry, _ := verified[0].Expiry(v.Symbol, v.Expiry)
+				value, err := cryptomarket.Value(v, verified[0].Quotes[v.Symbol], time.Now().UTC(), expiry)
+				if err != nil || value < 0 {
+					return fmt.Errorf("settle derivative liabilities before withdrawing; quote or expiry data may be unavailable")
+				}
+			}
+			v, err := addCreditsChecked(p.Credits, int(n))
+			if err != nil {
+				return err
+			}
+			p.Credits = v
+			p.Crypto.Balance -= n
+		}
+		return nil
+	})
+	if e != nil {
+		s.WriteLine(e.Error())
+		return
+	}
+	g.cryptoBalance(s)
+}
+func (g *Game) cryptoBalance(s *net.Session) {
+	s.WriteLine(g.colorize(s, "casino_credits", fmt.Sprintf("Exchange cash: %d credits | Bank: %d | Carried: %d", s.Player.Crypto.Balance, s.Player.BankedCredits, s.Player.Credits)))
+	if s.Player.Crypto.Balance < 0 {
+		s.WriteLine(g.colorize(s, "casino_result_loss", "DEBT: future bank deposits will be seized until paid. Use repay CREDITS."))
+	}
+}
+
+func (g *Game) executeCrypto(s *net.Session, action string, args []string) {
+	if s.CryptoBusy {
+		s.WriteLine("Crypto quotes are updating; wait or stop.")
+		g.cryptoHints(s)
+		return
+	}
+	hintsHandled := false
+	defer func() {
+		if !hintsHandled {
+			g.cryptoHints(s)
+		}
+	}()
+	if action == "back" {
+		action = "markets"
+		args = nil
+	}
+	if action == "refresh" {
+		action = s.CryptoScreen
+		if action == "" {
+			action = "markets"
+		}
+		if action == "view" {
+			args = []string{s.CryptoSelected}
+		}
+	}
+	switch action {
+	case "fund", "repay":
+		g.cryptoFunds(s, action, args)
+		return
+	case "closed":
+		g.cryptoPortfolio(s, cryptomarket.Snapshot{}, true)
+		return
+	case "contracts":
+		g.cryptoOptions(s)
+		return
+	}
+	// Parse and reject malformed commands BEFORE making any HTTP requests.
+	symbol, kind, quantity, strike := "", "", "", ""
+	days := 0
+	id := int64(0)
+	switch action {
+	case "withdraw":
+		if len(args) != 1 {
+			s.WriteLine("withdraw CREDITS")
+			return
+		}
+		n, err := strconv.ParseInt(args[0], 10, 64)
+		if err != nil || n <= 0 || n > cryptomarket.MaxMoney {
+			s.WriteLine("Enter a positive whole-credit amount within the economy limit.")
+			return
+		}
+	case "markets", "active", "portfolio":
+		if len(args) != 0 {
+			s.WriteLine("This command takes no arguments.")
+			return
+		}
+	case "view":
+		if len(args) != 1 {
+			s.WriteLine("view SYMBOL")
+			return
+		}
+		symbol = strings.ToUpper(args[0])
+	case "buy", "short":
+		if len(args) != 2 {
+			s.WriteLine(action + " SYMBOL QUANTITY")
+			return
+		}
+		symbol = strings.ToUpper(args[0])
+		quantity = args[1]
+		kind = "spot"
+		if action == "short" {
+			kind = "short"
+		}
+	case "option", "write", "quote":
+		validKind := len(args) > 0 && (args[0] == "call" || args[0] == "put" || (action == "quote" && (args[0] == "write-call" || args[0] == "write-put")))
+		if len(args) != 5 || !validKind {
+			s.WriteLine(action + " call|put SYMBOL QUANTITY STRIKE DAYS")
+			return
+		}
+		kind = args[0]
+		if action == "write" {
+			kind = "write-" + kind
+		}
+		symbol = strings.ToUpper(args[1])
+		quantity = args[2]
+		strike = args[3]
+		days, _ = strconv.Atoi(args[4])
+		if days != 1 && days != 7 && days != 30 {
+			s.WriteLine("DAYS must be 1, 7 or 30.")
+			return
+		}
+		if _, e := cryptomarket.Decimal(strike); e != nil {
+			s.WriteLine(e.Error())
+			return
+		}
+	case "sell", "cover", "close":
+		if len(args) != 1 {
+			s.WriteLine(action + " POSITION_ID")
+			return
+		}
+		id, _ = strconv.ParseInt(args[0], 10, 64)
+		found := false
+		for _, p := range s.Player.Crypto.Positions {
+			if p.ID == id && p.Status == "open" {
+				symbol = p.Symbol
+				found = true
+				if action == "cover" && p.Kind != "short" {
+					s.WriteLine("cover is for shorts; use close ID.")
+					return
+				}
+			}
+		}
+		if !found {
+			s.WriteLine("Choose an open position ID from active.")
+			return
+		}
+	default:
+		hintsHandled = true
+		g.cryptoHelp(s)
+		return
+	}
+	if symbol != "" {
+		if _, ok := cryptomarket.Find(symbol); !ok {
+			s.WriteLine("Supported currencies: BTC ETH SOL DOGE SHIB.")
+			return
+		}
+	}
+	if quantity != "" {
+		if _, e := cryptomarket.Decimal(quantity); e != nil {
+			s.WriteLine(e.Error())
+			return
+		}
+	}
+	symbols := map[string]bool{}
+	for _, sym := range cryptomarket.Symbols(s.Player.Crypto) {
+		symbols[sym] = true
+	}
+	if symbol != "" {
+		symbols[symbol] = true
+	}
+	if action == "markets" {
+		for _, i := range cryptomarket.Instruments {
+			symbols[i.Symbol] = true
+		}
+	}
+	list := []string{}
+	for sym := range symbols {
+		list = append(list, sym)
+	}
+	sort.Strings(list)
+	if g.CryptoClient == nil {
+		g.CryptoClient = cryptomarket.NewClient()
+	}
+	client := g.CryptoClient
+	p, room, epoch := s.Player, s.Player.RoomID, s.CryptoEpoch
+	ctx, cancel := context.WithTimeout(context.Background(), 50*time.Second)
+	s.CryptoCancel = cancel
+	s.CryptoBusy = true
+	hintsHandled = true
+	s.WriteLine("Updating crypto quotes...")
+	work := func() {
+		defer cancel()
+		snap, fetchErr := client.Fetch(ctx, list)
+		if ctx.Err() != nil {
+			fetchErr = ctx.Err()
+		}
+		apply := func() {
+			if !s.CryptoActive || s.CryptoEpoch != epoch {
+				return
+			}
+			s.CryptoBusy = false
+			s.CryptoCancel = nil
+			if g.isShuttingDown() || s.Player != p || s.State() != net.StateGame || s.IsDisconnecting() || p.RoomID != room || !g.atCryptoCounter(p) {
+				return
+			}
+			if g.owner != nil && g.loggedInChars[p.Name] != s {
+				return
+			}
+			if g.owner != nil {
+				defer g.reprompt(s)
+			}
+			defer g.cryptoHints(s)
+			s.CryptoUnavailable = fetchErr != nil
+			if fetchErr != nil {
+				g.predictionFrame(s, "COUNTER CLOSED", []string{"Prices are unavailable. Try refresh in a moment.", "No trade was made. Your positions are unchanged."})
+				g.cryptoBalance(s)
+				return
+			}
+			now := time.Now().UTC()
+			messages, e := g.reconcileCrypto(p, snap, now)
+			if e != nil {
+				s.WriteLine(e.Error())
+				return
+			}
+			for _, m := range messages {
+				s.WriteLine(m)
+			}
+			switch action {
+			case "withdraw":
+				g.cryptoFunds(s, action, args, snap)
+			case "markets":
+				g.cryptoMarkets(s, snap)
+			case "view":
+				s.CryptoSelected = symbol
+				g.cryptoView(s, symbol, snap)
+			case "active", "portfolio":
+				g.cryptoPortfolio(s, snap, false)
+			case "quote":
+				preview := p.Crypto.Clone()
+				preview.Balance = cryptomarket.MaxMoney
+				receipt, err := preview.Open(symbol, kind, quantity, strike, days, snap.Quotes[symbol], now)
+				if err != nil {
+					s.WriteLine(err.Error())
+					return
+				}
+				lines := []string{
+					g.colorize(s, "casino_emphasis", fmt.Sprintf("%s %s x %s", kind, symbol, quantity)),
+					fmt.Sprintf("Debit %s | premium %s | collateral %s credits",
+						g.colorize(s, "casino_credits", strconv.FormatInt(receipt.Cost, 10)),
+						g.colorize(s, "casino_credits", strconv.FormatInt(receipt.Premium, 10)),
+						g.colorize(s, "casino_credits", strconv.FormatInt(receipt.Collateral, 10))),
+					fmt.Sprintf("Strike %s | expires %s UTC", strike, time.Unix(receipt.Expiry, 0).UTC().Format("2006-01-02")),
+					g.colorize(s, "casino_action", "No order placed. Actual execution reprices."),
+				}
+				g.predictionFrame(s, "INDICATIVE QUOTE", lines)
+			default:
+				var receipt cryptomarket.Position
+				e = g.cryptoTransaction(p, func() error {
+					if id > 0 {
+						var err error
+						receipt, err = p.Crypto.Close(id, snap, now, "closed")
+						return err
+					}
+					// No new risk while an expired contract lacks its settlement data.
+					for _, v := range p.Crypto.Positions {
+						if v.Status != "open" {
+							continue
+						}
+						if v.Option() && v.Expiry <= now.Unix() {
+							return fmt.Errorf("settlement data pending; new positions are paused")
+						}
+						if v.Risky() || v.Option() {
+							if _, err := cryptomarket.Value(v, snap.Quotes[v.Symbol], now, ""); err != nil {
+								return fmt.Errorf("existing derivative cannot be valued; new positions are paused")
+							}
+						}
+					}
+					var err error
+					receipt, err = p.Crypto.Open(symbol, kind, quantity, strike, days, snap.Quotes[symbol], now)
+					return err
+				})
+				if e != nil {
+					s.WriteLine(e.Error())
+					return
+				}
+				if id > 0 {
+					category, verb := "casino_result_push", "released"
+					if receipt.Proceeds > 0 {
+						category = "casino_result_win"
+					} else if receipt.Proceeds < 0 {
+						category, verb = "casino_result_loss", "charged"
+					}
+					s.WriteLine(g.colorize(s, category, fmt.Sprintf("Closed #%d: %+d credits %s to exchange cash.", receipt.ID, receipt.Proceeds, verb)))
+				} else {
+					s.WriteLine(fmt.Sprintf("Opened #%d %s %s %s; debited %d credits.", receipt.ID, receipt.Kind, g.colorize(s, "casino_emphasis", receipt.Symbol), receipt.Quantity, receipt.Cost))
+					if receipt.Option() {
+						s.WriteLine(fmt.Sprintf("Strike %s; premium %d; expires %s UTC.", receipt.Strike, receipt.Premium, time.Unix(receipt.Expiry, 0).UTC().Format("2006-01-02 15:04")))
+					}
+				}
+				g.cryptoBalance(s)
+			}
+		}
+		if g.owner == nil {
+			apply()
+		} else {
+			g.run(apply)
+		}
+	}
+	if g.owner == nil {
+		work()
+	} else {
+		go work()
+	}
+}
+
+func (g *Game) cryptoMarkets(s *net.Session, snap cryptomarket.Snapshot) {
+	s.CryptoSelected = ""
+	s.CryptoScreen = "markets"
+	rows := [][]string{}
+	for _, i := range cryptomarket.Instruments {
+		q, ok := snap.Quotes[i.Symbol]
+		if !ok || q.Validate(time.Now()) != nil {
+			rows = append(rows, []string{
+				g.colorize(s, "casino_emphasis", i.Symbol),
+				g.colorize(s, "casino_menu", "--"),
+				g.colorize(s, "casino_menu", "--"),
+			})
+			continue
+		}
+		rows = append(rows, []string{
+			g.colorize(s, "casino_emphasis", i.Symbol),
+			g.colorize(s, "casino_result_loss", q.Ask),
+			g.colorize(s, "casino_result_win", q.Bid),
+		})
+	}
+	headers := []string{
+		g.colorize(s, "casino_menu", "Currency"),
+		g.colorize(s, "casino_menu", "Buy"),
+		g.colorize(s, "casino_menu", "Sell"),
+	}
+	g.predictionTable(s, g.colorize(s, "casino_emphasis", "CRYPTO EXCHANGE"), headers, rows, 0)
+	g.cryptoBalance(s)
+}
+func (g *Game) cryptoView(s *net.Session, symbol string, snap cryptomarket.Snapshot) {
+	s.CryptoScreen = "view"
+	q, ok := snap.Quotes[symbol]
+	if ok {
+		s.WriteLine(fmt.Sprintf("%s / USD: bid %s | ask %s | fetched %s UTC",
+			g.colorize(s, "casino_emphasis", symbol),
+			g.colorize(s, "casino_result_win", q.Bid),
+			g.colorize(s, "casino_result_loss", q.Ask),
+			q.At.UTC().Format("15:04:05")))
+	} else {
+		s.WriteLine(g.colorize(s, "casino_result_loss", symbol+": current quote unavailable"))
+	}
+	lines := cryptomarket.Chart(snap.Candles[symbol], predictionWidth(s)-4, s.Player.OptionBool("unicode"), func(text string, up bool) string {
+		key := "casino_result_loss"
+		if up {
+			key = "casino_result_win"
+		}
+		return g.colorize(s, key, text)
+	})
+	g.predictionFrame(s, symbol+" DAILY CANDLES", lines)
+	g.cryptoBalance(s)
+}
+func (g *Game) cryptoPortfolio(s *net.Session, snap cryptomarket.Snapshot, closed bool) {
+	s.CryptoScreen = "active"
+	if closed {
+		s.CryptoScreen = "closed"
+	}
+	now := time.Now().UTC()
+	rows := [][]string{}
+	for _, p := range s.Player.Crypto.Positions {
+		if (p.Status != "open") != closed {
+			continue
+		}
+		desc := p.Kind + " " + p.Symbol
+		if p.Option() {
+			desc += " " + p.Strike + " " + time.Unix(p.Expiry, 0).UTC().Format("01-02")
+		}
+		if closed {
+			desc += " (" + p.Status + ")"
+		}
+		if p.Risky() {
+			desc += " [coll " + strconv.FormatInt(p.Collateral, 10) + "]"
+		}
+		value, valued := int64(0), false
+		if closed {
+			value, valued = p.Proceeds, true
+		} else {
+			expiry, _ := snap.Expiry(p.Symbol, p.Expiry)
+			if v, e := cryptomarket.Value(p, snap.Quotes[p.Symbol], now, expiry); e == nil {
+				value, valued = v, true
+			}
+		}
+		valueText, pnlText := g.colorize(s, "casino_menu", "n/a"), g.colorize(s, "casino_menu", "n/a")
+		if valued {
+			valueText = strconv.FormatInt(value, 10)
+			pl := value - p.Cost
+			category := "casino_result_push"
+			if pl > 0 {
+				category = "casino_result_win"
+			} else if pl < 0 {
+				category = "casino_result_loss"
+			}
+			pnlText = g.colorize(s, category, fmt.Sprintf("%+d", pl))
+		}
+		rows = append(rows, []string{
+			g.colorize(s, "casino_menu", strconv.FormatInt(p.ID, 10)),
+			g.colorize(s, "casino_emphasis", desc),
+			p.Quantity,
+			strconv.FormatInt(p.Cost, 10),
+			valueText,
+			pnlText,
+		})
+	}
+	if len(rows) == 0 {
+		message := "No open positions. Use view SYMBOL to trade."
+		if closed {
+			message = "No completed trades yet."
+		}
+		g.predictionFrame(s, "CRYPTO PORTFOLIO", []string{message})
+		g.cryptoBalance(s)
+		return
+	}
+	headers := []string{"#", "Position", "Qty", "Cost"}
+	title := "CRYPTO POSITIONS"
+	last := "P/L"
+	if closed {
+		headers = append(headers, "Released")
+		title, last = "CRYPTO TRADE HISTORY", "Net"
+	} else {
+		headers = append(headers, "Value")
+	}
+	headers = append(headers, last)
+	colored := make([]string, len(headers))
+	for i, h := range headers {
+		colored[i] = g.colorize(s, "casino_menu", h)
+	}
+	g.predictionTable(s, g.colorize(s, "casino_emphasis", fmt.Sprintf("%s (%d)", title, len(rows))), colored, rows, 1)
+	g.cryptoBalance(s)
+}
diff --git a/internal/game/crypto_test.go b/internal/game/crypto_test.go
new file mode 100644
index 0000000..0ad5786
--- /dev/null
+++ b/internal/game/crypto_test.go
@@ -0,0 +1,384 @@
+package game
+
+import (
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"reflect"
+	"strings"
+	"testing"
+	"time"
+
+	"thehouseoficarus/internal/cryptomarket"
+	"thehouseoficarus/internal/net"
+	"thehouseoficarus/internal/player"
+	"thehouseoficarus/internal/world"
+)
+
+func cryptoFixture(t *testing.T) (*Game, *net.Session, *casinoTestConn) {
+	t.Helper()
+	g, s, c, _ := predictionFixture(t)
+	dir := t.TempDir()
+	if e := os.MkdirAll(filepath.Join(dir, "rooms"), 0755); e != nil {
+		t.Fatal(e)
+	}
+	if e := os.WriteFile(filepath.Join(dir, "rooms", "1.yaml"), []byte("name: Crypto\ncrypto_exchange: true\n"), 0644); e != nil {
+		t.Fatal(e)
+	}
+	g.World = world.New(dir)
+	s.CryptoActive = true
+	s.Player.Crypto.Balance = 1000
+	return g, s, c
+}
+func gameCryptoSnapshot(price string) cryptomarket.Snapshot {
+	return cryptomarket.Snapshot{Quotes: map[string]cryptomarket.Quote{"BTC": {Bid: price, Ask: price, At: time.Now().UTC()}}, Candles: map[string][]cryptomarket.Candle{}}
+}
+func TestCryptoFundsSaveAndDebtDepositRecovery(t *testing.T) {
+	g, s, c := cryptoFixture(t)
+	p := s.Player
+	g.cryptoFunds(s, "fund", []string{"100"})
+	if p.Credits != 9900 || p.Crypto.Balance != 1100 {
+		t.Fatal(p.Credits, p.Crypto)
+	}
+	g.cryptoFunds(s, "withdraw", []string{"50"})
+	if p.Credits != 9950 || p.Crypto.Balance != 1050 {
+		t.Fatal(p.Credits, p.Crypto)
+	}
+	p.Crypto.Balance = -150
+	p.BankedCredits = 0
+	g.doBankDepositCredits(s, []string{"deposit", "credits", "100"})
+	if p.Credits != 9850 || p.Crypto.Balance != -50 || p.BankedCredits != 0 {
+		t.Fatal(p.Credits, p.Crypto, p.BankedCredits)
+	}
+	if !strings.Contains(string(c.data), "seized 100") {
+		t.Fatal(c.data)
+	}
+	g.doBankDepositCredits(s, []string{"deposit", "credits", "100"})
+	if p.Credits != 9750 || p.Crypto.Balance != 0 || p.BankedCredits != 50 {
+		t.Fatal(p.Credits, p.Crypto, p.BankedCredits)
+	}
+	loaded, e := g.AccountStore.LoadCharacter(p.Name)
+	if e != nil || loaded.Crypto.Balance != 0 || loaded.BankedCredits != 50 || loaded.Credits != 9750 {
+		t.Fatal(loaded, e)
+	}
+}
+func TestCryptoLiquidationBankAndPersistentNegativeBalance(t *testing.T) {
+	g, s, _ := cryptoFixture(t)
+	p := s.Player
+	p.Crypto.Balance = 100
+	p.BankedCredits = 50
+	q := gameCryptoSnapshot("100").Quotes["BTC"]
+	if _, e := p.Crypto.Open("BTC", "short", "1", "", 0, q, time.Now().UTC()); e != nil {
+		t.Fatal(e)
+	}
+	messages, e := g.reconcileCrypto(p, gameCryptoSnapshot("300"), time.Now().UTC())
+	if e != nil || len(messages) != 2 {
+		t.Fatal(messages, e)
+	}
+	if p.Crypto.Balance != -50 || p.BankedCredits != 0 || p.Credits != 10000 {
+		t.Fatal(p.Crypto, p.BankedCredits, p.Credits)
+	}
+	loaded, e := g.AccountStore.LoadCharacter(p.Name)
+	if e != nil || loaded.Crypto.Balance != -50 || loaded.Crypto.Positions[0].Status != "liquidated" {
+		t.Fatal(loaded, e)
+	}
+	s.Player = loaded
+	g.cryptoFunds(s, "repay", []string{"50"})
+	if loaded.Crypto.Balance != 0 || loaded.Credits != 9950 {
+		t.Fatal(loaded.Crypto, loaded.Credits)
+	}
+}
+func TestCryptoAtomicRollbackIncludingBankGarnishment(t *testing.T) {
+	g, s, _ := cryptoFixture(t)
+	p := s.Player
+	p.Crypto.Balance = 100
+	p.BankedCredits = 50
+	q := gameCryptoSnapshot("100").Quotes["BTC"]
+	if _, e := p.Crypto.Open("BTC", "short", "1", "", 0, q, time.Now().UTC()); e != nil {
+		t.Fatal(e)
+	}
+	before := p.Crypto.Clone()
+	bank, credits := p.BankedCredits, p.Credits
+	// Force failure before rename by putting a directory at the target path.
+	if e := os.Mkdir(g.AccountStore.CharPath(p.Name), 0700); e != nil {
+		t.Fatal(e)
+	}
+	if _, e := g.reconcileCrypto(p, gameCryptoSnapshot("300"), time.Now().UTC()); e == nil {
+		t.Fatal("save succeeded")
+	}
+	if !reflect.DeepEqual(before, p.Crypto) || bank != p.BankedCredits || credits != p.Credits {
+		t.Fatal("partial rollback")
+	}
+	p.Crypto = cryptomarket.Account{Balance: -100}
+	before = p.Crypto.Clone()
+	g.doBankDepositCredits(s, []string{"deposit", "credits", "100"})
+	if !reflect.DeepEqual(before, p.Crypto) || p.Credits != credits || p.BankedCredits != bank {
+		t.Fatal("deposit rollback lost debt")
+	}
+}
+func TestCryptoWithdrawLocksAndBankCap(t *testing.T) {
+	g, s, c := cryptoFixture(t)
+	p := s.Player
+	q := gameCryptoSnapshot("100").Quotes["BTC"]
+	if _, e := p.Crypto.Open("BTC", "short", "1", "", 0, q, time.Now().UTC()); e != nil {
+		t.Fatal(e)
+	}
+	balance := p.Crypto.Balance
+	g.cryptoFunds(s, "withdraw", []string{"1"})
+	if p.Crypto.Balance != balance || !strings.Contains(string(c.data), "derivatives") {
+		t.Fatal(c.data)
+	}
+	p.Crypto = cryptomarket.Account{Balance: -10}
+	p.BankedCredits = int(cryptomarket.MaxMoney)
+	before := p.Credits
+	g.doBankDepositCredits(s, []string{"deposit", "credits", "10"})
+	if p.Crypto.Balance != 0 || p.BankedCredits != int(cryptomarket.MaxMoney) || p.Credits != before-10 {
+		t.Fatal("repayment at cap")
+	}
+	before = p.Credits
+	g.doBankDepositCredits(s, []string{"deposit", "credits", "1"})
+	if p.Credits != before || p.BankedCredits != int(cryptomarket.MaxMoney) {
+		t.Fatal("bank overflow")
+	}
+}
+func TestCryptoInterfaceIsolationAndMovement(t *testing.T) {
+	g, s, c := cryptoFixture(t)
+	if !g.cryptoInputOwned(s, "short") || g.cryptoInputOwned(s, "north") || g.cryptoInputOwned(s, "look") {
+		t.Fatal("ownership")
+	}
+	g.handleCryptoInput(s, "buy", []string{"BTC", "NaN"})
+	if !strings.Contains(string(c.data), "decimal") {
+		t.Fatal(c.data)
+	}
+	g.handleCryptoInput(s, "stop", nil)
+	if s.CryptoActive || g.cryptoInputOwned(s, "short") {
+		t.Fatal("stop")
+	}
+	s.CryptoActive = true
+	cancelled := false
+	s.CryptoCancel = func() { cancelled = true }
+	epoch := s.CryptoEpoch
+	h := net.NewHub()
+	h.EnterRoom(s, 2)
+	if s.CryptoActive || !cancelled || s.CryptoEpoch <= epoch {
+		t.Fatal("room change did not cancel")
+	}
+}
+func cryptoMockClient(t *testing.T, price string) *cryptomarket.Client {
+	t.Helper()
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		result := any(nil)
+		switch r.URL.Path {
+		case "/SystemStatus":
+			result = map[string]string{"status": "online"}
+		case "/AssetPairs":
+			m := map[string]any{}
+			for _, i := range cryptomarket.Instruments {
+				m[i.Key] = map[string]string{"status": "online"}
+			}
+			result = m
+		case "/Ticker":
+			m := map[string]any{}
+			for _, i := range cryptomarket.Instruments {
+				m[i.Key] = map[string]any{"a": []string{price}, "b": []string{price}}
+			}
+			result = m
+		case "/OHLC":
+			key := ""
+			for _, i := range cryptomarket.Instruments {
+				if i.Pair == r.URL.Query().Get("pair") {
+					key = i.Key
+				}
+			}
+			now := time.Now().UTC().Truncate(24 * time.Hour).Unix()
+			result = map[string]any{key: [][]any{{now - 172800, price, price, price, price, price, "1", 1}, {now - 86400, price, price, price, price, price, "1", 1}}}
+		default:
+			t.Errorf("unknown path %s", r.URL)
+		}
+		json.NewEncoder(w).Encode(map[string]any{"error": []string{}, "result": result})
+	}))
+	t.Cleanup(srv.Close)
+	c := cryptomarket.NewClient()
+	c.Base = srv.URL
+	return c
+}
+func TestCryptoRevisitSettlesOnlyVisitorAndNoRepeatedDebt(t *testing.T) {
+	g, s, _ := cryptoFixture(t)
+	p := s.Player
+	p.Crypto.Balance = 100
+	p.BankedCredits = 50
+	q := gameCryptoSnapshot("100").Quotes["BTC"]
+	if _, e := p.Crypto.Open("BTC", "short", "1", "", 0, q, time.Now().UTC()); e != nil {
+		t.Fatal(e)
+	}
+	if e := g.AccountStore.SaveCharacter(p); e != nil {
+		t.Fatal(e)
+	}
+	// Another character's position is untouched when this player visits.
+	offline := player.New("bob")
+	offline.Crypto = p.Crypto.Clone()
+	if e := g.AccountStore.SaveCharacter(offline); e != nil {
+		t.Fatal(e)
+	}
+	g.CryptoClient = cryptoMockClient(t, "300")
+	g.doUse(s, "crypto")
+	loaded, e := g.AccountStore.LoadCharacter(p.Name)
+	if e != nil || loaded.Crypto.Balance != -50 || loaded.BankedCredits != 0 {
+		t.Fatal(loaded, e)
+	}
+	saved, e := g.AccountStore.LoadCharacter("bob")
+	if e != nil || !reflect.DeepEqual(saved.Crypto, offline.Crypto) {
+		t.Fatal("offline position changed", saved, e)
+	}
+	for _, system := range TickSystemOrder() {
+		if strings.Contains(strings.ToLower(system.Name), "crypto") {
+			t.Fatal("crypto background tick registered")
+		}
+	}
+	before := loaded.Crypto.Clone()
+	g.executeCrypto(s, "active", nil)
+	loaded, e = g.AccountStore.LoadCharacter(p.Name)
+	if e != nil || !reflect.DeepEqual(before, loaded.Crypto) {
+		t.Fatal("repeat debt", loaded, e)
+	}
+}
+func TestCryptoCommandsTradeAndRender(t *testing.T) {
+	g, s, c := cryptoFixture(t)
+	g.CryptoClient = cryptoMockClient(t, "100")
+	g.doUse(s, "crypto")
+	if !s.CryptoActive {
+		t.Fatal("use crypto did not open counter")
+	}
+	before := s.Player.Crypto.Clone()
+	g.executeCrypto(s, "quote", []string{"write-call", "BTC", "10", "100", "7"})
+	if !reflect.DeepEqual(before, s.Player.Crypto) || !strings.Contains(string(c.data), "No order placed") {
+		t.Fatal("quote mutated ledger", string(c.data))
+	}
+	g.executeCrypto(s, "buy", []string{"BTC", "1.005"})
+	if len(s.Player.Crypto.Positions) != 1 || s.Player.Crypto.Balance != 899 {
+		t.Fatal(s.Player.Crypto, c.data)
+	}
+	g.executeCrypto(s, "view", []string{"BTC"})
+	if !strings.Contains(string(c.data), "DAILY CANDLES") {
+		t.Fatal(c.data)
+	}
+	g.executeCrypto(s, "sell", []string{"1"})
+	if s.Player.Crypto.Positions[0].Status != "closed" {
+		t.Fatal(c.data)
+	}
+	if s.Player.Crypto.Balance != 1000 {
+		t.Fatal(s.Player.Crypto)
+	}
+}
+func TestCryptoInteractionUsesLivePlayerNotOldFile(t *testing.T) {
+	g, s, _ := cryptoFixture(t)
+	p := s.Player
+	p.Crypto.Balance = 100
+	q := gameCryptoSnapshot("100").Quotes["BTC"]
+	if _, e := p.Crypto.Open("BTC", "short", "1", "", 0, q, time.Now().UTC()); e != nil {
+		t.Fatal(e)
+	}
+	if e := g.AccountStore.SaveCharacter(p); e != nil {
+		t.Fatal(e)
+	}
+	p.Credits = 1234
+	g.loggedInChars = map[string]*net.Session{p.Name: s}
+	g.CryptoClient = cryptoMockClient(t, "300")
+	g.executeCrypto(s, "active", nil)
+	loaded, e := g.AccountStore.LoadCharacter(p.Name)
+	if e != nil || loaded.Credits != 1234 || loaded.Crypto.Balance != -100 {
+		t.Fatal(loaded, e)
+	}
+}
+func TestCryptoAsyncMovementCancelsWithoutBlockingOwner(t *testing.T) {
+	g, s, _ := cryptoFixture(t)
+	started, release := make(chan struct{}), make(chan struct{})
+	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		if r.URL.Path == "/SystemStatus" {
+			close(started)
+			<-release
+			json.NewEncoder(w).Encode(map[string]any{"error": []string{}, "result": map[string]string{"status": "online"}})
+			return
+		}
+		w.WriteHeader(503)
+	}))
+	defer srv.Close()
+	g.CryptoClient = cryptomarket.NewClient()
+	g.CryptoClient.Base = srv.URL
+	g.owner = newOwner()
+	defer g.owner.stop()
+	g.loggedInChars = map[string]*net.Session{s.Player.Name: s}
+	g.run(func() { g.executeCrypto(s, "buy", []string{"BTC", "1"}) })
+	select {
+	case <-started:
+	case <-time.After(time.Second):
+		close(release)
+		t.Fatal("fetch not started")
+	}
+	moved := make(chan struct{})
+	go func() { g.run(func() { s.Player.RoomID = 2 }); close(moved) }()
+	select {
+	case <-moved:
+	case <-time.After(time.Second):
+		close(release)
+		t.Fatal("HTTP blocked owner")
+	}
+	close(release)
+	deadline := time.Now().Add(2 * time.Second)
+	for {
+		busy := true
+		g.run(func() { busy = s.CryptoBusy })
+		if !busy {
+			break
+		}
+		if time.Now().After(deadline) {
+			t.Fatal("callback stalled")
+		}
+		time.Sleep(time.Millisecond)
+	}
+	g.run(func() {
+		if s.Player.Crypto.Balance != 1000 || len(s.Player.Crypto.Positions) != 0 {
+			t.Error("trade after movement")
+		}
+	})
+}
+func TestCryptoVerifiedWithdrawDoesNotReleaseCollateral(t *testing.T) {
+	g, s, _ := cryptoFixture(t)
+	p := s.Player
+	snap := gameCryptoSnapshot("100")
+	if _, e := p.Crypto.Open("BTC", "short", "1", "", 0, snap.Quotes["BTC"], time.Now().UTC()); e != nil {
+		t.Fatal(e)
+	}
+	g.cryptoFunds(s, "withdraw", []string{"900"}, snap)
+	if p.Crypto.Balance != 0 || p.Crypto.Positions[0].Collateral != 100 || p.Credits != 10900 {
+		t.Fatal(p.Crypto, p.Credits)
+	}
+	g.cryptoFunds(s, "withdraw", []string{"1"}, snap)
+	if p.Crypto.Balance != 0 {
+		t.Fatal("withdrew collateral")
+	}
+}
+func TestCryptoSaveRoundTrip(t *testing.T) {
+	g, s, _ := cryptoFixture(t)
+	p := s.Player
+	p.Crypto.Balance = 100
+	now := time.Now().UTC()
+	q := cryptomarket.Quote{Bid: "0.000006", Ask: "0.000006", At: now}
+	if _, e := p.Crypto.Open("SHIB", "spot", "10000000.123456789012345678", "", 0, q, now); e != nil {
+		t.Fatal(e)
+	}
+	if e := g.AccountStore.SaveCharacter(p); e != nil {
+		t.Fatal(e)
+	}
+	loaded, e := g.AccountStore.LoadCharacter(p.Name)
+	if e != nil || !reflect.DeepEqual(p.Crypto, loaded.Crypto) {
+		t.Fatal(loaded, e)
+	}
+	// Old characters without any crypto fields still have valid empty accounts.
+	old := player.New("old")
+	if e := old.Crypto.Validate(); e != nil {
+		t.Fatal(e)
+	}
+}
diff --git a/internal/game/crypto_ux_test.go b/internal/game/crypto_ux_test.go
new file mode 100644
index 0000000..6ac4a57
--- /dev/null
+++ b/internal/game/crypto_ux_test.go
@@ -0,0 +1,147 @@
+package game
+
+import (
+	"strings"
+	"testing"
+
+	"thehouseoficarus/internal/casino"
+	"thehouseoficarus/internal/color"
+)
+
+func TestCryptoEntryIsBoardAndSharedHintsNotRules(t *testing.T) {
+	g, s, conn := cryptoFixture(t)
+	g.CryptoClient = cryptoMockClient(t, "100")
+	g.doUse(s, "crypto")
+	out := string(conn.data)
+	for _, wanted := range []string{"CRYPTO EXCHANGE", "Currency", "Buy", "Sell", "BTC", "view SYMBOL", "fund CREDITS", "stop"} {
+		if !strings.Contains(out, wanted) {
+			t.Fatalf("missing %q: %s", wanted, out)
+		}
+	}
+	for _, unwanted := range []string{"HOW TO TRADE", "Paper trading only", "HOUSE-MODEL", "volatility", "collateral", "Black-Scholes", "0.5%", "10-credit", "1,000,000"} {
+		if strings.Contains(out, unwanted) {
+			t.Fatalf("entry dumped rules %q: %s", unwanted, out)
+		}
+	}
+	for _, line := range strings.Split(out, "\n") {
+		if color.VisibleLen(strings.TrimSuffix(line, "\r")) > 80 {
+			t.Fatalf("wide entry line: %q", line)
+		}
+	}
+}
+func TestCryptoHintPreferencesAndExplicitWhat(t *testing.T) {
+	for _, mode := range []string{"off", "once", "on"} {
+		t.Run(mode, func(t *testing.T) {
+			g, s, conn := cryptoFixture(t)
+			g.CryptoClient = cryptoMockClient(t, "100")
+			s.Player.Options["casino_hints"] = mode
+			g.doUse(s, "crypto")
+			if got := strings.Contains(string(conn.data), "view SYMBOL"); got != (mode != "off") {
+				t.Fatalf("entry hints %s: %s", mode, conn.data)
+			}
+			conn.data = nil
+			g.executeCrypto(s, "refresh", nil)
+			if got := strings.Contains(string(conn.data), "view SYMBOL"); got != (mode == "on") {
+				t.Fatalf("repeat hints %s: %s", mode, conn.data)
+			}
+			conn.data = nil
+			// Look marks the same ShowHints flag the prediction counter uses.
+			s.CryptoShowHints = true
+			g.executeCrypto(s, "refresh", nil)
+			if got := strings.Contains(string(conn.data), "view SYMBOL"); got != (mode != "off") {
+				t.Fatalf("look hints %s: %s", mode, conn.data)
+			}
+			conn.data = nil
+			g.handleGameCommand(s, "what")
+			if !strings.Contains(string(conn.data), "view SYMBOL") || strings.Contains(string(conn.data), "HOW TO TRADE") {
+				t.Fatalf("what did not show command menu: %s", conn.data)
+			}
+			if g.cryptoInputOwned(s, "what") || g.cryptoInputOwned(s, "verbs") || g.cryptoInputOwned(s, "north") {
+				t.Fatal("counter stole a world command")
+			}
+		})
+	}
+}
+func TestCryptoContextMenusAndRefresh(t *testing.T) {
+	g, s, conn := cryptoFixture(t)
+	g.CryptoClient = cryptoMockClient(t, "100")
+	s.Player.Options["casino_hints"] = "on"
+	g.executeCrypto(s, "view", []string{"BTC"})
+	if !strings.Contains(string(conn.data), "buy BTC AMOUNT") || !strings.Contains(string(conn.data), "contracts") {
+		t.Fatalf("missing currency hints: %s", conn.data)
+	}
+	conn.data = nil
+	g.executeCrypto(s, "contracts", nil)
+	if !strings.Contains(string(conn.data), "option TYPE BTC") || !strings.Contains(string(conn.data), "quote TYPE BTC") {
+		t.Fatalf("missing option hints: %s", conn.data)
+	}
+	conn.data = nil
+	g.executeCrypto(s, "active", nil)
+	g.executeCrypto(s, "refresh", nil)
+	if s.CryptoScreen != "active" || strings.Contains(string(conn.data), "DAILY CANDLES") || !strings.Contains(string(conn.data), "close ID") {
+		t.Fatalf("refresh left portfolio: %s", conn.data)
+	}
+	conn.data = nil
+	g.executeCrypto(s, "closed", nil)
+	g.executeCrypto(s, "refresh", nil)
+	if s.CryptoScreen != "closed" || strings.Contains(string(conn.data), "close ID") {
+		t.Fatalf("closed hints or refresh wrong: %s", conn.data)
+	}
+	conn.data = nil
+	g.executeCrypto(s, "back", nil)
+	if s.CryptoScreen != "markets" || !strings.Contains(string(conn.data), "view SYMBOL") {
+		t.Fatalf("back failed: %s", conn.data)
+	}
+	s.CryptoBusy = true
+	commands := g.cryptoCommands(s)
+	if len(commands) != 1 || commands[0] != (casino.MenuCommand{Command: "stop", Desc: "Leave and cancel the update"}) {
+		t.Fatal(commands)
+	}
+}
+func TestCryptoGlobalOptionCommandsStayReachable(t *testing.T) {
+	g, s, _ := cryptoFixture(t)
+	g.CryptoClient = cryptoMockClient(t, "100")
+	// The settings command is not claimed by the counter...
+	if g.cryptoInputOwned(s, "options") {
+		t.Fatal("counter stole the options settings command")
+	}
+	if g.handleCryptoInput(s, "option", nil) {
+		t.Fatal("bare option should fall through to settings")
+	}
+	// ...but a real option trade is claimed.
+	if !g.cryptoInputOwned(s, "option") {
+		t.Fatal("option trade should be owned")
+	}
+	if !g.handleCryptoInput(s, "option", []string{"call", "BTC", "0.01", "100", "7"}) {
+		t.Fatal("option trade was not handled")
+	}
+}
+
+func TestCryptoCommandAbbreviations(t *testing.T) {
+	g, s, conn := cryptoFixture(t)
+	g.CryptoClient = cryptoMockClient(t, "100")
+	// Unique prefixes resolve like every other counter command.
+	if got, ok := cryptoVerb("mar"); !ok || got != "markets" {
+		t.Fatalf("mar -> %q, %v", got, ok)
+	}
+	if got, ok := cryptoVerb("opt"); !ok || got != "option" {
+		t.Fatalf("opt -> %q, %v", got, ok)
+	}
+	if !g.cryptoInputOwned(s, "mar") {
+		t.Fatal("mar should be owned")
+	}
+	// Ambiguous shortcuts are claimed and explained instead of running.
+	if got, ok := cryptoVerb("b"); !ok || got != "" {
+		t.Fatalf("b -> %q, %v", got, ok)
+	}
+	conn.data = nil
+	if !g.handleCryptoInput(s, "b", nil) || !strings.Contains(string(conn.data), "ambiguous") {
+		t.Fatalf("ambiguous shortcut: %s", conn.data)
+	}
+	// Real world commands still win over counter prefixes.
+	for _, cmd := range []string{"look", "north", "score", "inventory"} {
+		if got, ok := cryptoVerb(cmd); ok {
+			t.Fatalf("%s was claimed as %q", cmd, got)
+		}
+	}
+}
diff --git a/internal/game/game.go b/internal/game/game.go
index 1ce89e5..0c550ae 100644
--- a/internal/game/game.go
+++ b/internal/game/game.go
@@ -15,6 +15,7 @@ import (
 	"thehouseoficarus/internal/casino"
 	"thehouseoficarus/internal/combat"
 	"thehouseoficarus/internal/config"
+	"thehouseoficarus/internal/cryptomarket"
 	"thehouseoficarus/internal/engine"
 	"thehouseoficarus/internal/game/hacking"
 	"thehouseoficarus/internal/item"
@@ -62,6 +63,7 @@ type Game struct {
 	GlobalFlags      *GlobalFlagStore
 	Combat           *combat.Tracker
 	PredictionClient *prediction.Client
+	CryptoClient     *cryptomarket.Client
 	Casino           *casino.Manager
 	flagIndex        *flagTriggerIndex
 	queue            *CommandQueue
@@ -632,7 +634,7 @@ func (g *Game) handleGameCommand(sess *net.Session, input string) {
 	cmd := parts[0]
 
 	// Counter commands exist only while using the counter, before global prefixes.
-	if g.predictionInputOwned(sess, cmd) {
+	if g.cryptoInputOwned(sess, cmd) || g.predictionInputOwned(sess, cmd) {
 		g.executeCommand(sess, cmd, parts[1:], input)
 		g.writePrompt(sess)
 		return
diff --git a/internal/game/prediction_interface.go b/internal/game/prediction_interface.go
index 2e37145..3281f2d 100644
--- a/internal/game/prediction_interface.go
+++ b/internal/game/prediction_interface.go
@@ -29,6 +29,7 @@ func (g *Game) openPredictionCounter(s *net.Session) {
 		g.executePredictions(s, []string{"refresh"}, "")
 		return
 	}
+	g.closeCryptoCounter(s)
 	s.PredictionActive = true
 	s.PredictionEpoch++
 	s.PredictionBusy = false
diff --git a/internal/game/render_crypto.go b/internal/game/render_crypto.go
new file mode 100644
index 0000000..899f83b
--- /dev/null
+++ b/internal/game/render_crypto.go
@@ -0,0 +1,63 @@
+package game
+
+import (
+	"thehouseoficarus/internal/casino"
+	"thehouseoficarus/internal/net"
+)
+
+// Use the same contextual command columns and casino_hints policy as the
+// prediction counter and casino tables. Rules are opt-in, never an entry screen.
+func (g *Game) cryptoCommands(s *net.Session) []casino.MenuCommand {
+	if s.CryptoBusy {
+		return []casino.MenuCommand{{Command: "stop", Desc: "Leave and cancel the update"}}
+	}
+	commands := []casino.MenuCommand{}
+	if !s.CryptoUnavailable {
+		symbol := s.CryptoSelected
+		if symbol == "" {
+			symbol = "SYMBOL"
+		}
+		switch s.CryptoScreen {
+		case "view":
+			commands = append(commands,
+				casino.MenuCommand{Command: "buy " + symbol + " AMOUNT", Desc: "Buy coins"},
+				casino.MenuCommand{Command: "short " + symbol + " AMOUNT", Desc: "Back a falling price"},
+				casino.MenuCommand{Command: "contracts", Desc: "Trade calls and puts"},
+				casino.MenuCommand{Command: "back", Desc: "Return to the currencies"})
+		case "contracts":
+			commands = append(commands,
+				casino.MenuCommand{Command: "quote TYPE " + symbol + " AMOUNT PRICE DAYS", Desc: "Preview a call, put, write-call or write-put"},
+				casino.MenuCommand{Command: "option TYPE " + symbol + " AMOUNT PRICE DAYS", Desc: "Buy a call or put"},
+				casino.MenuCommand{Command: "write TYPE " + symbol + " AMOUNT PRICE DAYS", Desc: "Write a call or put; risk of debt"},
+				casino.MenuCommand{Command: "back", Desc: "Return to the currencies"})
+		case "active":
+			commands = append(commands, casino.MenuCommand{Command: "close ID", Desc: "Close a whole position"}, casino.MenuCommand{Command: "view SYMBOL", Desc: "View a currency's chart"})
+		default:
+			commands = append(commands, casino.MenuCommand{Command: "view SYMBOL", Desc: "Choose a currency"})
+		}
+		commands = append(commands, casino.MenuCommand{Command: "active", Desc: "Your open positions"}, casino.MenuCommand{Command: "closed", Desc: "Your completed trades"})
+	}
+	if s.Player.Crypto.Balance < 0 {
+		commands = append(commands, casino.MenuCommand{Command: "repay CREDITS", Desc: "Pay your exchange debt"})
+	} else {
+		commands = append(commands, casino.MenuCommand{Command: "fund CREDITS", Desc: "Add trading funds"}, casino.MenuCommand{Command: "withdraw CREDITS", Desc: "Take out available credits"})
+	}
+	return append(commands, casino.MenuCommand{Command: "rules", Desc: "How to trade"}, casino.MenuCommand{Command: "refresh", Desc: "Update this screen"}, casino.MenuCommand{Command: "stop", Desc: "Leave the counter"})
+}
+func (g *Game) cryptoHints(s *net.Session, force ...bool) {
+	forced := len(force) > 0 && force[0]
+	show := g.casinoHintsVisible(s, &casino.MenuView{ShowHints: s.CryptoShowHints})
+	s.CryptoShowHints = false
+	if !forced && !show {
+		return
+	}
+	s.WriteLine("")
+	s.WriteLine(g.renderCasinoCommands(s, "", "", g.cryptoCommands(s)))
+}
+func (g *Game) cryptoOptions(s *net.Session) {
+	s.CryptoScreen = "contracts"
+	g.predictionFrame(s, "OPTIONS", []string{
+		"Choose a call for a rising price, or a put for a falling price. Preview with quote before buying or writing.",
+		"AMOUNT is coins, PRICE is your target, and DAYS is 1, 7 or 30. Writing options can leave you owing credits.",
+	})
+}