Fix SSE architecture for reliable connections (#13)

features/c4game/handlers.go

@@ -1,47 +1,23 @@
 package c4game
 
 import (
-	"fmt"
 	"net/http"
 	"strconv"
 	"time"
 
 	"github.com/alexedwards/scs/v2"
 	"github.com/go-chi/chi/v5"
-	"github.com/nats-io/nats.go"
 	"github.com/starfederation/datastar-go/datastar"
 
 	"github.com/ryanhamamura/games/chat"
 	chatcomponents "github.com/ryanhamamura/games/chat/components"
 	"github.com/ryanhamamura/games/connect4"
-	"github.com/ryanhamamura/games/db/repository"
 	"github.com/ryanhamamura/games/features/c4game/pages"
-	sharedcomponents "github.com/ryanhamamura/games/features/common/components"
+	"github.com/ryanhamamura/games/features/c4game/services"
 	"github.com/ryanhamamura/games/sessions"
 )
 
-// c4ChatColors maps player color (1=Red, 2=Yellow) to CSS background colors.
-var c4ChatColors = map[int]string{
-	0: "#4a2a3a", // color 1 stored as slot 0
-	1: "#2a4545", // color 2 stored as slot 1
-}
-
-func c4ChatColor(slot int) string {
-	if c, ok := c4ChatColors[slot]; ok {
-		return c
-	}
-	return "#666"
-}
-
-func c4ChatConfig(gameID string) chatcomponents.Config {
-	return chatcomponents.Config{
-		CSSPrefix: "c4",
-		PostURL:   fmt.Sprintf("/games/%s/chat", gameID),
-		Color:     c4ChatColor,
-	}
-}
-
-func HandleGamePage(store *connect4.Store, sm *scs.SessionManager, queries *repository.Queries) http.HandlerFunc {
+func HandleGamePage(store *connect4.Store, svc *services.GameService, sm *scs.SessionManager) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		gameID := chi.URLParam(r, "id")
 
@@ -85,16 +61,17 @@ func HandleGamePage(store *connect4.Store, sm *scs.SessionManager, queries *repo
 		}
 
 		g := gi.GetGame()
-		room := chat.NewPersistentRoom(nil, "", queries, gameID)
+		room := svc.ChatRoom(gameID)
 
-		if err := pages.GamePage(g, myColor, room.Messages(), c4ChatConfig(gameID)).Render(r.Context(), w); err != nil {
+		if err := pages.GamePage(g, myColor, room.Messages(), svc.ChatConfig(gameID)).Render(r.Context(), w); err != nil {
 			http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
 		}
 	}
 }
 
-func HandleGameEvents(store *connect4.Store, nc *nats.Conn, sm *scs.SessionManager, queries *repository.Queries) http.HandlerFunc {
+func HandleGameEvents(store *connect4.Store, svc *services.GameService, sm *scs.SessionManager) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
+		ctx := r.Context()
 		gameID := chi.URLParam(r, "id")
 
 		gi, exists := store.Get(gameID)
@@ -104,68 +81,74 @@ func HandleGameEvents(store *connect4.Store, nc *nats.Conn, sm *scs.SessionManag
 		}
 
 		playerID := sessions.GetPlayerID(sm, r)
-		myColor := gi.GetPlayerColor(playerID)
 
-		sse := datastar.NewSSE(w, r, datastar.WithCompression(
-			datastar.WithBrotli(datastar.WithBrotliLevel(5)),
-		))
-
-		chatCfg := c4ChatConfig(gameID)
-		room := chat.NewPersistentRoom(nc, connect4.ChatSubject(gameID), queries, gameID)
-
-		patchAll := func() error {
-			myColor = gi.GetPlayerColor(playerID)
-			g := gi.GetGame()
-			return sse.PatchElementTempl(pages.GameContent(g, myColor, room.Messages(), chatCfg))
-		}
-
-		sendPing := func() error {
-			return sse.PatchElementTempl(sharedcomponents.ConnectionIndicator(time.Now().UnixMilli()))
-		}
-
-		// Send initial render and ping
-		if err := sendPing(); err != nil {
-			return
-		}
-		if err := patchAll(); err != nil {
-			return
-		}
-
-		heartbeat := time.NewTicker(15 * time.Second)
-		defer heartbeat.Stop()
-
-		// Subscribe to game state updates
-		gameCh := make(chan *nats.Msg, 64)
-		gameSub, err := nc.ChanSubscribe(connect4.GameSubject(gameID), gameCh)
+		// Subscribe to game state updates BEFORE creating SSE
+		gameSub, gameCh, err := svc.SubscribeGameUpdates(gameID)
 		if err != nil {
+			http.Error(w, err.Error(), http.StatusInternalServerError)
 			return
 		}
 		defer gameSub.Unsubscribe() //nolint:errcheck
 
-		// Subscribe to chat messages
+		// Subscribe to chat messages BEFORE creating SSE
+		chatCfg := svc.ChatConfig(gameID)
+		room := svc.ChatRoom(gameID)
 		chatCh, cleanupChat := room.Subscribe()
 		defer cleanupChat()
 
-		ctx := r.Context()
+		// Setup heartbeat BEFORE creating SSE
+		heartbeat := time.NewTicker(1 * time.Second)
+		defer heartbeat.Stop()
+
+		// NOW create SSE
+		sse := datastar.NewSSE(w, r, datastar.WithCompression(
+			datastar.WithBrotli(datastar.WithBrotliLevel(5)),
+		))
+
+		// Define patch function
+		patchAll := func() error {
+			myColor := gi.GetPlayerColor(playerID)
+			g := gi.GetGame()
+			return sse.PatchElementTempl(pages.GameContent(g, myColor, room.Messages(), chatCfg))
+		}
+
+		// Send initial state
+		if err := patchAll(); err != nil {
+			return
+		}
+
+		// Event loop
 		for {
 			select {
 			case <-ctx.Done():
 				return
-			case <-heartbeat.C:
-				if err := sendPing(); err != nil {
-					return
-				}
+
 			case <-gameCh:
+				// Drain rapid-fire notifications
+			drainGame:
+				for {
+					select {
+					case <-gameCh:
+					default:
+						break drainGame
+					}
+				}
 				if err := patchAll(); err != nil {
 					return
 				}
+
 			case chatMsg := <-chatCh:
-				err := sse.PatchElementTempl(
+				if err := sse.PatchElementTempl(
 					chatcomponents.ChatMessage(chatMsg, chatCfg),
 					datastar.WithSelectorID("c4-chat-history"),
 					datastar.WithModeAppend(),
-				)
-				if err != nil {
+				); err != nil {
+					return
+				}
+
+			case <-heartbeat.C:
+				// Heartbeat refreshes game state to keep connection alive
+				if err := patchAll(); err != nil {
 					return
 				}
 			}
@@ -202,7 +185,7 @@ func HandleDropPiece(store *connect4.Store, sm *scs.SessionManager) http.Handler
 	}
 }
 
-func HandleSendChat(store *connect4.Store, nc *nats.Conn, sm *scs.SessionManager, queries *repository.Queries) http.HandlerFunc {
+func HandleSendChat(store *connect4.Store, svc *services.GameService, sm *scs.SessionManager) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		gameID := chi.URLParam(r, "id")
 
@@ -249,7 +232,7 @@ func HandleSendChat(store *connect4.Store, nc *nats.Conn, sm *scs.SessionManager
 			Message:  signals.ChatMsg,
 			Time:     time.Now().UnixMilli(),
 		}
-		room := chat.NewPersistentRoom(nc, connect4.ChatSubject(gameID), queries, gameID)
+		room := svc.ChatRoom(gameID)
 		room.Send(msg)
 
 		sse := datastar.NewSSE(w, r)

features/c4game/pages/game.templ

@@ -18,7 +18,6 @@ templ GamePage(g *connect4.Game, myColor int, messages []chat.Message, chatCfg c
 			data-signals="{chatMsg: ''}"
 			data-init={ fmt.Sprintf("@get('/games/%s/events',{requestCancellation:'disabled'})", g.ID) }
 		>
-			@sharedcomponents.ConnectionIndicator(0)
 			@GameContent(g, myColor, messages, chatCfg)
 		</main>
 	}
@@ -26,6 +25,7 @@ templ GamePage(g *connect4.Game, myColor int, messages []chat.Message, chatCfg c
 
 templ GameContent(g *connect4.Game, myColor int, messages []chat.Message, chatCfg chatcomponents.Config) {
 	<div id="game-content">
+		@sharedcomponents.LiveClock()
 		@sharedcomponents.BackToLobby()
 		@sharedcomponents.StealthTitle("text-3xl font-bold")
 		@components.PlayerInfo(g, myColor)

features/c4game/routes.go

@@ -4,24 +4,22 @@ package c4game
 import (
 	"github.com/alexedwards/scs/v2"
 	"github.com/go-chi/chi/v5"
-	"github.com/nats-io/nats.go"
 
 	"github.com/ryanhamamura/games/connect4"
-	"github.com/ryanhamamura/games/db/repository"
+	"github.com/ryanhamamura/games/features/c4game/services"
 )
 
 func SetupRoutes(
 	router chi.Router,
 	store *connect4.Store,
-	nc *nats.Conn,
+	svc *services.GameService,
 	sessions *scs.SessionManager,
-	queries *repository.Queries,
 ) {
 	router.Route("/games/{id}", func(r chi.Router) {
-		r.Get("/", HandleGamePage(store, sessions, queries))
-		r.Get("/events", HandleGameEvents(store, nc, sessions, queries))
+		r.Get("/", HandleGamePage(store, svc, sessions))
+		r.Get("/events", HandleGameEvents(store, svc, sessions))
 		r.Post("/drop", HandleDropPiece(store, sessions))
-		r.Post("/chat", HandleSendChat(store, nc, sessions, queries))
+		r.Post("/chat", HandleSendChat(store, svc, sessions))
 		r.Post("/join", HandleSetNickname(store, sessions))
 		r.Post("/rematch", HandleRematch(store, sessions))
 	})

features/c4game/services/game_service.go

@@ -0,0 +1,70 @@
+// Package services provides the game service layer for Connect 4,
+// handling NATS subscriptions and chat room management.
+package services
+
+import (
+	"fmt"
+
+	"github.com/nats-io/nats.go"
+
+	"github.com/ryanhamamura/games/chat"
+	chatcomponents "github.com/ryanhamamura/games/chat/components"
+	"github.com/ryanhamamura/games/connect4"
+	"github.com/ryanhamamura/games/db/repository"
+)
+
+// c4ChatColors maps player slot (0-indexed) to CSS background colors.
+var c4ChatColors = map[int]string{
+	0: "#4a2a3a", // Red player
+	1: "#2a4545", // Yellow player
+}
+
+func c4ChatColor(slot int) string {
+	if c, ok := c4ChatColors[slot]; ok {
+		return c
+	}
+	return "#666"
+}
+
+// GameService manages NATS subscriptions and chat for Connect 4 games.
+type GameService struct {
+	nc      *nats.Conn
+	queries *repository.Queries
+}
+
+// NewGameService creates a new game service.
+func NewGameService(nc *nats.Conn, queries *repository.Queries) *GameService {
+	return &GameService{
+		nc:      nc,
+		queries: queries,
+	}
+}
+
+// SubscribeGameUpdates returns a NATS subscription and channel for game state updates.
+func (s *GameService) SubscribeGameUpdates(gameID string) (*nats.Subscription, <-chan *nats.Msg, error) {
+	ch := make(chan *nats.Msg, 64)
+	sub, err := s.nc.ChanSubscribe(connect4.GameSubject(gameID), ch)
+	if err != nil {
+		return nil, nil, fmt.Errorf("subscribing to game updates: %w", err)
+	}
+	return sub, ch, nil
+}
+
+// ChatConfig returns the chat configuration for a game.
+func (s *GameService) ChatConfig(gameID string) chatcomponents.Config {
+	return chatcomponents.Config{
+		CSSPrefix: "c4",
+		PostURL:   fmt.Sprintf("/games/%s/chat", gameID),
+		Color:     c4ChatColor,
+	}
+}
+
+// ChatRoom returns a persistent chat room for a game.
+func (s *GameService) ChatRoom(gameID string) *chat.Room {
+	return chat.NewPersistentRoom(s.nc, connect4.ChatSubject(gameID), s.queries, gameID)
+}
+
+// PublishGameUpdate sends a notification that the game state has changed.
+func (s *GameService) PublishGameUpdate(gameID string) error {
+	return s.nc.Publish(connect4.GameSubject(gameID), nil)
+}

features/common/components/shared.templ

@@ -1,7 +1,7 @@
 package components
 
 import (
-	"fmt"
+	"time"
 
 	"github.com/starfederation/datastar-go/datastar"
 )
@@ -48,60 +48,13 @@ templ NicknamePrompt(returnPath string) {
 	</main>
 }
 
-func isStale(lastPing int64) bool {
-	return lastPing == 0
-}
-
-var connectionWatcherHandle = templ.NewOnceHandle()
-
-// ConnectionIndicator shows a small dot indicating SSE connection status.
-// Server patches this with a timestamp; client JS detects staleness.
-templ ConnectionIndicator(lastPing int64) {
-	<div
-		id="connection-indicator"
-		class="fixed top-2 right-2"
-		data-last-ping={ fmt.Sprintf("%d", lastPing) }
-	>
-		<div class="inline-grid *:[grid-area:1/1]">
-			<div
-				id="connection-ping"
-				class={
-					"status status-sm",
-					templ.KV("status-success animate-ping", !isStale(lastPing)),
-					templ.KV("status-error", isStale(lastPing)),
-				}
-			></div>
-			<div
-				id="connection-dot"
-				class={
-					"status status-sm",
-					templ.KV("status-success", !isStale(lastPing)),
-					templ.KV("status-error", isStale(lastPing)),
-				}
-			></div>
-		</div>
+// LiveClock shows the current server time, updated every second via SSE.
+// If the clock stops updating, users know the connection is stale.
+templ LiveClock() {
+	<div class="fixed top-2 right-2 flex items-center gap-1.5 text-xs opacity-60 font-mono">
+		<div style="width: 6px; height: 6px; border-radius: 50%; background-color: #22c55e;"></div>
+		{ time.Now().Format("15:04:05") }
 	</div>
-	@connectionWatcherHandle.Once() {
-		@connectionWatcher()
-	}
-}
-
-script connectionWatcher() {
-	setInterval(function() {
-		var el = document.getElementById('connection-indicator');
-		var dot = document.getElementById('connection-dot');
-		var ping = document.getElementById('connection-ping');
-		if (!el || !dot || !ping) return;
-		
-		var lastPing = parseInt(el.dataset.lastPing, 10) || 0;
-		var stale = Date.now() - lastPing > 20000;
-		
-		dot.classList.toggle('status-success', !stale);
-		dot.classList.toggle('status-error', stale);
-		ping.classList.toggle('status-success', !stale);
-		ping.classList.toggle('status-error', stale);
-		ping.classList.toggle('animate-ping', !stale);
-	}, 1000);
 }
 
 templ GameJoinPrompt(loginURL string, registerURL string, gamePath string) {

features/common/layouts/base.templ

@@ -1,6 +1,7 @@
 package layouts
 
 import (
+	"github.com/ryanhamamura/games/assets"
 	"github.com/ryanhamamura/games/config"
 	"github.com/ryanhamamura/games/version"
 )
@@ -11,8 +12,8 @@ templ Base(title string) {
 		<head>
 			<title>{ title }</title>
 			<meta name="viewport" content="width=device-width, initial-scale=1, maximum-scale=1, user-scalable=0"/>
-			<script defer type="module" src="/assets/js/datastar.js"></script>
-			<link href="/assets/css/output.css" rel="stylesheet" type="text/css"/>
+			<script defer type="module" src={ assets.StaticPath("js/datastar.js") }></script>
+			<link href={ assets.StaticPath("css/output.css") } rel="stylesheet" type="text/css"/>
 		</head>
 		<body class="flex flex-col h-screen">
 			if config.Global.Environment == config.Dev {

features/snakegame/handlers.go

@@ -1,41 +1,24 @@
 package snakegame
 
 import (
-	"fmt"
+	"errors"
 	"net/http"
 	"strconv"
 	"time"
 
 	"github.com/alexedwards/scs/v2"
 	"github.com/go-chi/chi/v5"
-	"github.com/nats-io/nats.go"
 	"github.com/starfederation/datastar-go/datastar"
 
 	"github.com/ryanhamamura/games/chat"
 	chatcomponents "github.com/ryanhamamura/games/chat/components"
-	sharedcomponents "github.com/ryanhamamura/games/features/common/components"
 	"github.com/ryanhamamura/games/features/snakegame/pages"
+	"github.com/ryanhamamura/games/features/snakegame/services"
 	"github.com/ryanhamamura/games/sessions"
 	"github.com/ryanhamamura/games/snake"
 )
 
-func snakeChatColor(slot int) string {
-	if slot >= 0 && slot < len(snake.SnakeColors) {
-		return snake.SnakeColors[slot]
-	}
-	return "#666"
-}
-
-func snakeChatConfig(gameID string) chatcomponents.Config {
-	return chatcomponents.Config{
-		CSSPrefix:          "snake",
-		PostURL:            fmt.Sprintf("/snake/%s/chat", gameID),
-		Color:              snakeChatColor,
-		StopKeyPropagation: true,
-	}
-}
-
-func HandleSnakePage(snakeStore *snake.SnakeStore, sm *scs.SessionManager) http.HandlerFunc {
+func HandleSnakePage(snakeStore *snake.SnakeStore, svc *services.GameService, sm *scs.SessionManager) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		gameID := chi.URLParam(r, "id")
 		si, ok := snakeStore.Get(gameID)
@@ -77,13 +60,14 @@ func HandleSnakePage(snakeStore *snake.SnakeStore, sm *scs.SessionManager) http.
 		}
 
 		sg := si.GetGame()
-		if err := pages.GamePage(sg, mySlot, nil, snakeChatConfig(gameID), gameID).Render(r.Context(), w); err != nil {
+		chatCfg := svc.ChatConfig(gameID)
+		if err := pages.GamePage(sg, mySlot, nil, chatCfg, gameID).Render(r.Context(), w); err != nil {
 			http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
 		}
 	}
 }
 
-func HandleSnakeEvents(snakeStore *snake.SnakeStore, nc *nats.Conn, sm *scs.SessionManager) http.HandlerFunc {
+func HandleSnakeEvents(snakeStore *snake.SnakeStore, svc *services.GameService, sm *scs.SessionManager) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		gameID := chi.URLParam(r, "id")
 		si, ok := snakeStore.Get(gameID)
@@ -95,17 +79,25 @@ func HandleSnakeEvents(snakeStore *snake.SnakeStore, nc *nats.Conn, sm *scs.Sess
 		playerID := sessions.GetPlayerID(sm, r)
 		mySlot := si.GetPlayerSlot(playerID)
 
+		// Subscribe to game updates BEFORE creating SSE (following portigo pattern)
+		gameSub, gameCh, err := svc.SubscribeGameUpdates(gameID)
+		if err != nil {
+			http.Error(w, http.StatusText(http.StatusInternalServerError), http.StatusInternalServerError)
+			return
+		}
+		defer gameSub.Unsubscribe() //nolint:errcheck
+
 		sse := datastar.NewSSE(w, r, datastar.WithCompression(
 			datastar.WithBrotli(datastar.WithBrotliLevel(5)),
 		))
 
-		chatCfg := snakeChatConfig(gameID)
+		chatCfg := svc.ChatConfig(gameID)
 
 		// Chat room (multiplayer only)
 		var room *chat.Room
 		sg := si.GetGame()
 		if sg.Mode == snake.ModeMultiplayer {
-			room = chat.NewRoom(nc, snake.ChatSubject(gameID))
+			room = svc.ChatRoom(gameID)
 		}
 
 		chatMessages := func() []chat.Message {
@@ -118,36 +110,21 @@ func HandleSnakeEvents(snakeStore *snake.SnakeStore, nc *nats.Conn, sm *scs.Sess
 		patchAll := func() error {
 			si, ok = snakeStore.Get(gameID)
 			if !ok {
-				return fmt.Errorf("game not found")
+				return errors.New("game not found")
 			}
 			mySlot = si.GetPlayerSlot(playerID)
 			sg = si.GetGame()
 			return sse.PatchElementTempl(pages.GameContent(sg, mySlot, chatMessages(), chatCfg, gameID))
 		}
 
-		sendPing := func() error {
-			return sse.PatchElementTempl(sharedcomponents.ConnectionIndicator(time.Now().UnixMilli()))
-		}
-
-		// Send initial render and ping
-		if err := sendPing(); err != nil {
-			return
-		}
+		// Send initial render
 		if err := patchAll(); err != nil {
 			return
 		}
 
-		heartbeat := time.NewTicker(15 * time.Second)
+		heartbeat := time.NewTicker(1 * time.Second)
 		defer heartbeat.Stop()
 
-		// Subscribe to game updates via NATS
-		gameCh := make(chan *nats.Msg, 64)
-		gameSub, err := nc.ChanSubscribe(snake.GameSubject(gameID), gameCh)
-		if err != nil {
-			return
-		}
-		defer gameSub.Unsubscribe() //nolint:errcheck
-
 		// Chat subscription (multiplayer only)
 		var chatCh <-chan chat.Message
 		var cleanupChat func()
@@ -164,7 +141,8 @@ func HandleSnakeEvents(snakeStore *snake.SnakeStore, nc *nats.Conn, sm *scs.Sess
 				return
 
 			case <-heartbeat.C:
-				if err := sendPing(); err != nil {
+				// Heartbeat refreshes game state to keep connection alive
+				if err := patchAll(); err != nil {
 					return
 				}
 
@@ -231,7 +209,7 @@ type chatSignals struct {
 	ChatMsg string `json:"chatMsg"`
 }
 
-func HandleSendChat(snakeStore *snake.SnakeStore, nc *nats.Conn, sm *scs.SessionManager) http.HandlerFunc {
+func HandleSendChat(snakeStore *snake.SnakeStore, svc *services.GameService, sm *scs.SessionManager) http.HandlerFunc {
 	return func(w http.ResponseWriter, r *http.Request) {
 		gameID := chi.URLParam(r, "id")
 		si, ok := snakeStore.Get(gameID)
@@ -264,7 +242,7 @@ func HandleSendChat(snakeStore *snake.SnakeStore, nc *nats.Conn, sm *scs.Session
 			Message:  signals.ChatMsg,
 		}
 
-		room := chat.NewRoom(nc, snake.ChatSubject(gameID))
+		room := svc.ChatRoom(gameID)
 		room.Send(msg)
 
 		sse := datastar.NewSSE(w, r)

features/snakegame/pages/game.templ

@@ -37,7 +37,6 @@ templ GamePage(sg *snake.SnakeGame, mySlot int, messages []chat.Message, chatCfg
 			data-on:keydown__throttle.100ms={ keydownScript(gameID) }
 			tabindex="0"
 		>
-			@components.ConnectionIndicator(0)
 			@GameContent(sg, mySlot, messages, chatCfg, gameID)
 		</main>
 	}
@@ -45,6 +44,7 @@ templ GamePage(sg *snake.SnakeGame, mySlot int, messages []chat.Message, chatCfg
 
 templ GameContent(sg *snake.SnakeGame, mySlot int, messages []chat.Message, chatCfg chatcomponents.Config, gameID string) {
 	<div id="game-content">
+		@components.LiveClock()
 		@components.BackToLobby()
 		<h1 class="text-3xl font-bold">~~~~</h1>
 		@snakecomponents.PlayerList(sg, mySlot)

features/snakegame/routes.go

@@ -4,17 +4,17 @@ package snakegame
 import (
 	"github.com/alexedwards/scs/v2"
 	"github.com/go-chi/chi/v5"
-	"github.com/nats-io/nats.go"
 
+	"github.com/ryanhamamura/games/features/snakegame/services"
 	"github.com/ryanhamamura/games/snake"
 )
 
-func SetupRoutes(router chi.Router, snakeStore *snake.SnakeStore, nc *nats.Conn, sessions *scs.SessionManager) {
+func SetupRoutes(router chi.Router, snakeStore *snake.SnakeStore, svc *services.GameService, sessions *scs.SessionManager) {
 	router.Route("/snake/{id}", func(r chi.Router) {
-		r.Get("/", HandleSnakePage(snakeStore, sessions))
-		r.Get("/events", HandleSnakeEvents(snakeStore, nc, sessions))
+		r.Get("/", HandleSnakePage(snakeStore, svc, sessions))
+		r.Get("/events", HandleSnakeEvents(snakeStore, svc, sessions))
 		r.Post("/dir", HandleSetDirection(snakeStore, sessions))
-		r.Post("/chat", HandleSendChat(snakeStore, nc, sessions))
+		r.Post("/chat", HandleSendChat(snakeStore, svc, sessions))
 		r.Post("/join", HandleSetNickname(snakeStore, sessions))
 		r.Post("/rematch", HandleRematch(snakeStore, sessions))
 	})

features/snakegame/services/game_service.go

@@ -0,0 +1,62 @@
+// Package services provides the game service layer for Snake,
+// handling NATS subscriptions and chat room management.
+package services
+
+import (
+	"fmt"
+
+	"github.com/nats-io/nats.go"
+
+	"github.com/ryanhamamura/games/chat"
+	chatcomponents "github.com/ryanhamamura/games/chat/components"
+	"github.com/ryanhamamura/games/snake"
+)
+
+func snakeChatColor(slot int) string {
+	if slot >= 0 && slot < len(snake.SnakeColors) {
+		return snake.SnakeColors[slot]
+	}
+	return "#666"
+}
+
+// GameService manages NATS subscriptions and chat for Snake games.
+type GameService struct {
+	nc *nats.Conn
+}
+
+// NewGameService creates a new game service.
+func NewGameService(nc *nats.Conn) *GameService {
+	return &GameService{
+		nc: nc,
+	}
+}
+
+// SubscribeGameUpdates returns a NATS subscription and channel for game state updates.
+func (s *GameService) SubscribeGameUpdates(gameID string) (*nats.Subscription, <-chan *nats.Msg, error) {
+	ch := make(chan *nats.Msg, 64)
+	sub, err := s.nc.ChanSubscribe(snake.GameSubject(gameID), ch)
+	if err != nil {
+		return nil, nil, fmt.Errorf("subscribing to game updates: %w", err)
+	}
+	return sub, ch, nil
+}
+
+// ChatConfig returns the chat configuration for a game.
+func (s *GameService) ChatConfig(gameID string) chatcomponents.Config {
+	return chatcomponents.Config{
+		CSSPrefix:          "snake",
+		PostURL:            fmt.Sprintf("/snake/%s/chat", gameID),
+		Color:              snakeChatColor,
+		StopKeyPropagation: true,
+	}
+}
+
+// ChatRoom returns a chat room for a game (ephemeral, not persisted).
+func (s *GameService) ChatRoom(gameID string) *chat.Room {
+	return chat.NewRoom(s.nc, snake.ChatSubject(gameID))
+}
+
+// PublishGameUpdate sends a notification that the game state has changed.
+func (s *GameService) PublishGameUpdate(gameID string) error {
+	return s.nc.Publish(snake.GameSubject(gameID), nil)
+}