feat: casino framework and basic slot machine

1 files changed, 217 insertions, 0 deletions

diff --git a/internal/casino/table.go b/internal/casino/table.go
new file mode 100644
index 0000000..1b9d0b5
--- /dev/null
+++ b/internal/casino/table.go
@@ -0,0 +1,217 @@
+package casino
+
+import (
+	"fmt"
+	"math/rand"
+	"sync"
+)
+
+type tablePhase string
+
+const (
+	phaseWaiting tablePhase = "waiting"
+	phaseBetting tablePhase = "betting"
+)
+
+type Table struct {
+	mu     sync.Mutex
+	RoomID int
+	Config TableConfig
+
+	participants map[string]*Participant
+	order        []string
+	phase        tablePhase
+	deadline     int
+	clock        int
+	rng          *rand.Rand
+}
+
+func newTable(roomID int, cfg TableConfig, rng *rand.Rand) *Table {
+	return &Table{
+		RoomID:       roomID,
+		Config:       cfg,
+		phase:        phaseWaiting,
+		participants: make(map[string]*Participant),
+		rng:          rng,
+	}
+}
+
+func (t *Table) join(name string) []Event {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	if p := t.participants[name]; p != nil {
+		p.Connected = true
+		return []Event{{RoomID: t.RoomID, TableID: t.Config.ID, Type: EventJoined, Player: name, PrivateTo: name, Message: fmt.Sprintf("You resume your place at the %s table.", t.Config.ID)}}
+	}
+	if len(t.participants) >= t.Config.MaxPlayers {
+		return []Event{{RoomID: t.RoomID, TableID: t.Config.ID, Type: EventResult, Player: name, PrivateTo: name, Message: "That table is full."}}
+	}
+	t.participants[name] = &Participant{Name: name, Connected: true}
+	t.order = append(t.order, name)
+	return []Event{{RoomID: t.RoomID, TableID: t.Config.ID, Type: EventJoined, Player: name, Message: fmt.Sprintf("%s joins the %s table.", name, t.Config.ID), Public: true}}
+}
+
+func (t *Table) leave(name string) []Event {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	p := t.participants[name]
+	if p == nil {
+		return nil
+	}
+	if t.phase != phaseWaiting {
+		return []Event{{RoomID: t.RoomID, TableID: t.Config.ID, Type: EventResult, Player: name, PrivateTo: name, Message: "You're in the middle of a game!"}}
+	}
+	delete(t.participants, name)
+	for i, n := range t.order {
+		if n == name {
+			t.order = append(t.order[:i], t.order[i+1:]...)
+			break
+		}
+	}
+	events := []Event{{RoomID: t.RoomID, TableID: t.Config.ID, Type: EventLeft, Player: name, Message: fmt.Sprintf("%s stops playing at the %s table.", name, t.Config.ID), Public: true}}
+	if len(t.participants) == 0 {
+		events = append(events, Event{RoomID: t.RoomID, TableID: t.Config.ID, Type: EventClosed, Message: fmt.Sprintf("The %s table closes.", t.Config.ID), Public: true})
+	}
+	return events
+}
+
+func (t *Table) bet(name string, amount int, wallet Wallet) []Event {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	p := t.participants[name]
+	if p == nil {
+		return []Event{{RoomID: t.RoomID, TableID: t.Config.ID, Type: EventResult, Player: name, PrivateTo: name, Message: "You aren't playing at that table."}}
+	}
+	if t.phase != phaseWaiting && t.phase != phaseBetting {
+		return []Event{{RoomID: t.RoomID, TableID: t.Config.ID, Type: EventResult, Player: name, PrivateTo: name, Message: "That table isn't accepting bets."}}
+	}
+	if amount < t.Config.MinBet || amount > t.Config.MaxBet {
+		return []Event{{RoomID: t.RoomID, TableID: t.Config.ID, Type: EventResult, Player: name, PrivateTo: name, Message: fmt.Sprintf("Bets must be between %d and %d.", t.Config.MinBet, t.Config.MaxBet)}}
+	}
+	if p.HasBet {
+		return []Event{{RoomID: t.RoomID, TableID: t.Config.ID, Type: EventResult, Player: name, PrivateTo: name, Message: "You have already bet this round."}}
+	}
+	wager, ok := wallet.Wager(amount)
+	if !ok {
+		return []Event{{RoomID: t.RoomID, TableID: t.Config.ID, Type: EventResult, Player: name, PrivateTo: name, Message: "You don't have enough chips and credits for that bet."}}
+	}
+	p.HasBet = true
+	p.Wager = wager
+	p.Wallet = wallet
+	if t.phase == phaseWaiting && len(t.participants) > 1 {
+		t.phase = phaseBetting
+		t.clock = 0
+		t.deadline = t.Config.BettingTicks
+	}
+	events := []Event{{RoomID: t.RoomID, TableID: t.Config.ID, Type: EventBetPlaced, Player: name, Message: fmt.Sprintf("%s bets %d credits at the %s table.", name, amount, t.Config.ID), Public: true}}
+	if t.phase == phaseBetting && t.clock == 0 {
+		events = append(events, Event{RoomID: t.RoomID, TableID: t.Config.ID, Type: EventBetting, Message: fmt.Sprintf("Betting is open at the %s table for %d ticks.", t.Config.ID, t.deadline), Public: true})
+	}
+	if len(t.participants) == 1 || t.allBet() {
+		events = append(events, t.resolveRound()...)
+	}
+	return events
+}
+
+func (t *Table) tick() []Event {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	if t.phase != phaseBetting {
+		return nil
+	}
+	t.clock++
+	if t.allBet() {
+		return t.resolveRound()
+	}
+	if t.clock < t.deadline {
+		return nil
+	}
+	var events []Event
+	for _, name := range t.order {
+		p := t.participants[name]
+		if p != nil && !p.HasBet {
+			events = append(events, Event{RoomID: t.RoomID, TableID: t.Config.ID, Type: EventTimedOut, Player: name, Message: fmt.Sprintf("%s sits out this round.", name), Public: true})
+		}
+	}
+	if t.anyBet() {
+		events = append(events, t.resolveRound()...)
+	} else {
+		t.resetRound()
+	}
+	return events
+}
+
+func (t *Table) resolveRound() []Event {
+	var events []Event
+	for _, name := range t.order {
+		p := t.participants[name]
+		if p == nil || !p.HasBet {
+			continue
+		}
+		result := slotResult(t.rng, p.Wager.Total)
+		message := fmt.Sprintf("%s spins: %s", name, result.Display)
+		events = append(events, Event{RoomID: t.RoomID, TableID: t.Config.ID, Type: EventRoundStarted, Player: name, Message: message, Public: true})
+		if result.Payout > 0 {
+			if p.Wallet != nil {
+				p.Wallet.PayCredits(result.Payout)
+			}
+			events = append(events, Event{RoomID: t.RoomID, TableID: t.Config.ID, Type: EventPayout, Player: name, PrivateTo: name, Message: fmt.Sprintf("You win %d credits!", result.Payout)})
+		}
+	}
+	t.resetRound()
+	return events
+}
+
+func (t *Table) resetRound() {
+	t.phase = phaseWaiting
+	t.clock = 0
+	t.deadline = 0
+	for _, p := range t.participants {
+		p.HasBet = false
+		p.Wager = Wager{}
+	}
+}
+
+func (t *Table) allBet() bool {
+	if len(t.participants) == 0 {
+		return false
+	}
+	for _, p := range t.participants {
+		if !p.HasBet {
+			return false
+		}
+	}
+	return true
+}
+
+func (t *Table) anyBet() bool {
+	for _, p := range t.participants {
+		if p.HasBet {
+			return true
+		}
+	}
+	return false
+}
+
+func (t *Table) markDisconnected(name string) []Event {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	if p := t.participants[name]; p != nil {
+		p.Connected = false
+	}
+	return nil
+}
+
+func (t *Table) markConnected(name string) {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	if p := t.participants[name]; p != nil {
+		p.Connected = true
+	}
+}
+
+func (t *Table) hasParticipant(name string) bool {
+	t.mu.Lock()
+	defer t.mu.Unlock()
+	return t.participants[name] != nil
+}