feat: casino framework and basic slot machine

1 files changed, 364 insertions, 0 deletions

diff --git a/internal/casino/machine.go b/internal/casino/machine.go
new file mode 100644
index 0000000..d9fa590
--- /dev/null
+++ b/internal/casino/machine.go
@@ -0,0 +1,364 @@
+package casino
+
+import (
+	"fmt"
+	"math/rand"
+	"sync"
+)
+
+type machinePhase string
+
+const (
+	machineReady    machinePhase = "ready"
+	machineSpinning machinePhase = "spinning"
+	machinePayout   machinePhase = "payout"
+	payoutDelay                  = 2
+)
+
+type Machine struct {
+	mu              sync.Mutex
+	RoomID          int
+	Config          MachineConfig
+	player          *Participant
+	bet             int
+	phase           machinePhase
+	spin            *SlotSpin
+	reel            int
+	clock           int
+	freeSpins       int
+	spinBet         int
+	payoutRemainder float64
+	profile         SlotProfile
+	rng             *rand.Rand
+	suspense        bool
+	autoBet         bool
+	autoCountdown   int
+}
+
+func newMachine(roomID int, cfg MachineConfig, rng *rand.Rand) *Machine {
+	profile := DefaultHuffAndPuffProfile()
+	if cfg.Payout > 0 {
+		profile = ScaleToRTP(profile, cfg.Payout)
+	}
+	return &Machine{RoomID: roomID, Config: cfg, phase: machineReady, profile: profile, rng: rng}
+}
+
+func (m *Machine) join(name string) []Event {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	if m.player != nil && m.player.Name != name {
+		return []Event{{RoomID: m.RoomID, TableID: m.Config.ID, Type: EventResult, PrivateTo: name, Message: "That slot machine is occupied."}}
+	}
+	if m.player == nil {
+		m.player = &Participant{Name: name, Connected: true}
+		events := []Event{{RoomID: m.RoomID, TableID: m.Config.ID, Type: EventJoined, Player: name,
+			Message:        fmt.Sprintf("%s sits down at the slots machine.", name),
+			PrivateMessage: "You sit down at the slot machine.", PrivateTo: name, Color: "casino_action", Public: true}}
+		return append(events, m.privateMenu("You sit down at the slot machine.")...)
+	}
+	m.player.Connected = true
+	if m.autoBet {
+		return m.private("Autobet is active. Type \"stop\" to stop playing.")
+	}
+	return m.menuEvents("You resume your place at the slot machine.")
+}
+
+func (m *Machine) setBet(name string, amount int) []Event {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	if !m.owns(name) {
+		return m.private("You aren't playing at a slot machine.")
+	}
+	if m.autoBet {
+		return m.private("Autobet is active. Type \"stop\" to stop playing.")
+	}
+	if m.phase != machineReady {
+		return m.private("You're in the middle of a spin!")
+	}
+	if amount < m.Config.MinBet || amount > m.Config.MaxBet {
+		return m.private(fmt.Sprintf("Slot machine bets must be between %d and %d.", m.Config.MinBet, m.Config.MaxBet))
+	}
+	m.bet = amount
+	return m.menuEvents(fmt.Sprintf("Your slot machine bet is set to %d.", amount))
+}
+
+func (m *Machine) start(name string, wallet Wallet) []Event {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	if !m.owns(name) {
+		return m.private("You aren't playing at a slot machine.")
+	}
+	if m.autoBet {
+		return m.private("Autobet is active. Type \"stop\" to stop playing.")
+	}
+	if m.phase != machineReady {
+		return m.private("You're in the middle of a spin!")
+	}
+	if m.bet <= 0 {
+		return m.private("Set a wager first with 'bet <amount>'.")
+	}
+	wager := m.bet
+	if m.freeSpins > 0 {
+		m.spinBet = wager
+	} else {
+		if _, ok := wallet.Wager(wager); !ok {
+			return m.private("You don't have enough chips and credits for that bet.")
+		}
+		m.spinBet = wager
+	}
+	m.player.Wallet = wallet
+	m.spin = generateSlotSpinWithProfile(m.rng, m.spinBet, m.profile)
+	m.reel, m.clock, m.suspense = 0, 0, false
+	m.phase = machineSpinning
+	if m.freeSpins > 0 {
+		m.freeSpins--
+		return m.playerAction(fmt.Sprintf("%s begins a free spin.", name), "You begin a free spin.")
+	}
+	return m.playerAction(fmt.Sprintf("%s pulls the lever on the slots machine.", name), "You pull the lever on the slots machine.")
+}
+
+func (m *Machine) enableAutoBet(name string, wallet Wallet) []Event {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	if !m.owns(name) {
+		return m.private("You aren't playing at a slot machine.")
+	}
+	if m.autoBet {
+		return m.private("Autobet is already active.")
+	}
+	if m.phase != machineReady {
+		return m.private("You're in the middle of a spin!")
+	}
+	if m.bet <= 0 {
+		return m.private("Set a wager first with 'bet <amount>'.")
+	}
+	m.player.Wallet = wallet
+	m.autoBet = true
+	m.autoCountdown = 0
+	return nil
+}
+
+func (m *Machine) stopAutoBet(name string) ([]Event, bool) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	if !m.owns(name) || !m.autoBet {
+		return nil, false
+	}
+	m.autoBet = false
+	m.autoCountdown = 0
+	return m.private("Autobet stopped. You remain at the slot machine."), true
+}
+
+func (m *Machine) tick() []Event {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	if m.phase == machineReady && m.autoBet {
+		return m.autoBetTick()
+	}
+	if (m.phase != machineSpinning && m.phase != machinePayout) || m.spin == nil {
+		return nil
+	}
+	if m.phase == machinePayout {
+		m.clock++
+		if m.clock < payoutDelay {
+			return nil
+		}
+		m.clock = 0
+		m.phase = machineReady
+		return m.finishSpin()
+	}
+	m.clock++
+	delay := m.Config.SpinTicks
+	if m.suspense && delay < 4 {
+		delay = 4
+	}
+	if m.clock < delay {
+		return nil
+	}
+	m.clock = 0
+	m.reel++
+	message := fmt.Sprintf("Reel %d stops...", m.reel)
+	events := m.publicSlot(message, m.reel)
+	if m.reel < 5 && stoppedScatters(m.spin.Grid, m.reel) >= 2 && !m.suspense {
+		m.suspense = true
+		events = append(events, m.public("Two scatters! The remaining reels slow down...")...)
+	}
+	if m.reel < 5 {
+		return events
+	}
+	m.phase = machinePayout
+	m.clock = 0
+	return events
+}
+
+func (m *Machine) autoBetTick() []Event {
+	m.autoCountdown++
+	switch m.autoCountdown {
+	case 1:
+		return m.private("Autobet enabled!")
+	case 2:
+		return m.private(`Type "stop" to stop playing`)
+	case 3:
+		m.autoCountdown = 0
+		if m.bet <= 0 || m.player.Wallet == nil {
+			m.autoBet = false
+			return m.private("Autobet stopped: no wager is set.")
+		}
+		if _, ok := m.player.Wallet.Wager(m.bet); !ok {
+			m.autoBet = false
+			return m.private("Autobet stopped: you don't have enough chips and credits for that bet.")
+		}
+		m.spinBet = m.bet
+		m.spin = generateSlotSpinWithProfile(m.rng, m.spinBet, m.profile)
+		m.reel, m.clock, m.suspense = 0, 0, false
+		m.phase = machineSpinning
+		return m.playerAction(fmt.Sprintf("%s starts an automatic spin.", m.player.Name), fmt.Sprintf("Betting... %d credits.", m.bet))
+	default:
+		return nil
+	}
+}
+
+func (m *Machine) finishSpin() []Event {
+	events := []Event{}
+	result := m.spin.Payout + m.payoutRemainder
+	credits := int(result)
+	m.payoutRemainder = result - float64(credits)
+	if credits > 0 && m.player.Wallet != nil {
+		m.player.Wallet.PayCredits(credits)
+	}
+	if credits > 0 {
+		winEvents := m.private(fmt.Sprintf("\nYou win %d credits.", credits))
+		winEvents[0].Color = "casino_payout"
+		if credits > m.spinBet {
+			winEvents[0].Color = "casino_big_win"
+		}
+		if credits >= 2*m.spinBet {
+			winEvents[0].Color = "casino_jackpot_win"
+		}
+		events = append(events, winEvents...)
+	}
+	if len(m.spin.Wins) > 0 {
+		winEvents := m.private(formatWins(m.spin.Wins))
+		winEvents[0].Color = "casino_win"
+		events = append(events, winEvents...)
+	}
+	if m.spin.ScatterCount >= 3 && m.freeSpins == 0 {
+		m.freeSpins = 8
+		events = append(events, m.public("Three scatter symbols trigger 8 free spins!")...)
+	}
+	if m.freeSpins > 0 {
+		m.freeSpins--
+		m.phase = machineSpinning
+		m.spin = generateSlotSpinWithProfile(m.rng, m.spinBet, m.profile)
+		m.reel, m.clock, m.suspense = 0, 0, false
+		events = append(events, m.public(fmt.Sprintf("%d free spins remain.", m.freeSpins))...)
+	} else if !m.autoBet {
+		events = append(events, m.menuEvents("")...)
+	}
+	return events
+}
+
+func (m *Machine) leave(name string) []Event {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	if !m.owns(name) {
+		return nil
+	}
+	if m.phase != machineReady {
+		return m.private("You're in the middle of a spin!")
+	}
+	m.player = nil
+	m.bet = 0
+	return []Event{{RoomID: m.RoomID, TableID: m.Config.ID, Type: EventLeft, Player: name,
+		Message: fmt.Sprintf("%s stands up from the slots machine.", name), PrivateMessage: "You stand up from the slot machine.", PrivateTo: name, Color: "casino_action", Public: true}}
+}
+
+func (m *Machine) markDisconnected(name string) []Event {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	if m.owns(name) {
+		m.player.Connected = false
+	}
+	return nil
+}
+
+func (m *Machine) markConnected(name string) {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	if m.owns(name) {
+		m.player.Connected = true
+	}
+}
+
+func (m *Machine) hasParticipant(name string) bool {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	return m.owns(name)
+}
+
+func (m *Machine) isBusy(name string) bool {
+	m.mu.Lock()
+	defer m.mu.Unlock()
+	return m.owns(name) && (m.autoBet || m.phase == machineSpinning || m.phase == machinePayout)
+}
+
+func (m *Machine) owns(name string) bool { return m.player != nil && m.player.Name == name }
+
+func (m *Machine) private(message string) []Event {
+	return []Event{{RoomID: m.RoomID, TableID: m.Config.ID, Type: EventResult, PrivateTo: m.player.Name, Message: message, Color: "casino_action"}}
+}
+
+func (m *Machine) public(message string) []Event {
+	return []Event{{RoomID: m.RoomID, TableID: m.Config.ID, Type: EventResult, Player: m.player.Name, Message: message, Color: "casino_action", Public: true}}
+}
+
+func (m *Machine) playerAction(publicMessage, privateMessage string) []Event {
+	return []Event{{RoomID: m.RoomID, TableID: m.Config.ID, Type: EventResult, Player: m.player.Name,
+		Message: publicMessage, PrivateMessage: privateMessage, PrivateTo: m.player.Name, Color: "casino_action", Public: true}}
+}
+
+func (m *Machine) publicSlot(message string, stopped int) []Event {
+	return []Event{{RoomID: m.RoomID, TableID: m.Config.ID, Type: EventResult, Player: m.player.Name,
+		Message: message, Color: "casino_action", Public: true, Slot: &SlotSnapshot{Grid: m.spin.Grid, StoppedReels: stopped}}}
+}
+
+func stoppedScatters(grid [3][5]string, reels int) int {
+	count := 0
+	for row := 0; row < 3; row++ {
+		for reel := 0; reel < reels && reel < 5; reel++ {
+			if grid[row][reel] == "scatter" {
+				count++
+			}
+		}
+	}
+	return count
+}
+
+func formatWins(wins []SlotWin) string {
+	message := "Winning lines/ways (243-way evaluation):\n"
+	for _, win := range wins {
+		message += fmt.Sprintf("  %s x%d: %d ways x %.4gx bet / 243 = %.4f credits\n", win.Symbol, win.Length, win.Ways, win.Multiplier, win.Payout)
+	}
+	return message[:len(message)-1]
+}
+
+func (m *Machine) privateMenu(prefix string) []Event {
+	if m.phase != machineReady {
+		events := m.private(prefix)
+		events[0].Color = "casino_menu"
+		return events
+	}
+	menu := "Slot machine commands:\n  bet <amount>  Set your wager\n  bet max       Set the maximum wager\n  spin          Spin using your current wager\n  autospin      Start automatic betting\n  stop          Leave the slot machine"
+	if prefix == "" {
+		prefix = "\n" + menu
+	} else {
+		prefix += "\n\n" + menu
+	}
+	events := m.private(prefix)
+	events[0].Color = "casino_menu"
+	return events
+}
+
+func (m *Machine) menuEvents(prefix string) []Event {
+	return m.privateMenu(prefix)
+}