backend for twitch chat widgets

twitch/twitch.go

@@ -38,6 +38,26 @@ type (
 		LatestSubscriber	*twitchLabel
 		LatestCheer			*twitchLabel
 	}
+	
+	ChatMessageModifier string
+	chatMessage struct {
+		ID string `json:"id"`
+		Username string `json:"username,omitempty"`
+		Colour string `json:"colour,omitempty"`
+		Text string `json:"text,omitempty"`
+		Fragments []api.ChatMessageFragment `json:"fragments,omitempty"`
+		Modifier ChatMessageModifier `json:"modifier,omitempty"`
+		AnnouncementColour string `json:"announcement_colour,omitempty"`
+	}
+	SystemChatMessageType string
+	systemChatMessage struct {
+		Text string `json:"text,omitempty"`
+		Type SystemChatMessageType `json:"type,omitempty"`
+	}
+	deleteChatMessage struct {
+		Username string `json:"username,omitempty"`
+		MessageID string `json:"message_id,omitempty"`
+	}
 
 	ServiceOptions struct {
 		Host string
@@ -63,6 +83,13 @@ type (
 
 		eventSubSession *api.EventSubSession
 		labels	*twitchLabels
+
+		ChatC chan *chatMessage
+		ChatBroadcast	broadcast.BroadcastChannel[*chatMessage]
+		SystemChatC chan *systemChatMessage
+		SystemChatBroadcast	broadcast.BroadcastChannel[*systemChatMessage]
+		DeleteChatC chan *deleteChatMessage
+		DeleteChatBroadcast	broadcast.BroadcastChannel[*deleteChatMessage]
 	}
 )
 
@@ -70,6 +97,20 @@ const (
 	LABEL_LATEST_FOLLOWER string	= "latest-follower"
 	LABEL_LATEST_SUBSCRIBER string	= "latest-subscriber"
 	LABEL_LATEST_CHEER string		= "latest-cheer"
+
+	CHAT_MODIFIER_NONE ChatMessageModifier = ""
+	CHAT_MODIFIER_SUBSCRIBE ChatMessageModifier = "subscribe"
+	CHAT_MODIFIER_CHEER ChatMessageModifier = "cheer"
+	CHAT_MODIFIER_HIGHLIGHT ChatMessageModifier = "highlight"
+	CHAT_MODIFIER_ANNOUNCEMENT ChatMessageModifier = "announcement"
+
+	SYSTEM_CHAT_FOLLOW SystemChatMessageType = "follow"
+	SYSTEM_CHAT_SUBSCRIBE SystemChatMessageType = "subscribe"
+	SYSTEM_CHAT_CHEER SystemChatMessageType = "cheer"
+	SYSTEM_CHAT_RAID SystemChatMessageType = "raid"
+	SYSTEM_CHAT_POLL SystemChatMessageType = "poll"
+	SYSTEM_CHAT_SHOUTOUT SystemChatMessageType = "shoutout"
+	SYSTEM_CHAT_POINT_REDEEM SystemChatMessageType = "point-redeem"
 )
 
 var DATA_PATH string = path.Join(config.CONFIG_DIR, "twitch")
@@ -98,6 +139,16 @@ func New(ctx context.Context, opts ServiceOptions) (*Service, error) {
 	latestCheerC := make(chan string)
 	latestCheerBroadcast := broadcast.NewBroadcastChannel(
 		ctx, latestCheerC)
+		
+	chatC := make(chan *chatMessage)
+	chatBroadcast := broadcast.NewBroadcastChannel(
+		ctx, chatC)
+	systemChatC := make(chan *systemChatMessage)
+	systemChatBroadcast := broadcast.NewBroadcastChannel(
+		ctx, systemChatC)
+	deleteChatC := make(chan *deleteChatMessage)
+	deleteChatBroadcast := broadcast.NewBroadcastChannel(
+		ctx, deleteChatC)
 
 	srv := &Service{
 		host: opts.Host,
@@ -138,6 +189,13 @@ func New(ctx context.Context, opts ServiceOptions) (*Service, error) {
 			},
 			RedirectURL: fmt.Sprintf("http://%s:%d/twitch/auth", opts.Host, opts.Port),
 		},
+
+		ChatC: chatC,
+		ChatBroadcast: chatBroadcast,
+		SystemChatC: systemChatC,
+		SystemChatBroadcast: systemChatBroadcast,
+		DeleteChatC: deleteChatC,
+		DeleteChatBroadcast: deleteChatBroadcast,
 	}
 
 	if authFile, err := os.OpenFile(AUTH_FILEPATH, os.O_RDONLY, 0600); err != nil {
@@ -203,7 +261,7 @@ func (srv *Service) BindRoutes(group *gin.RouterGroup) {
 		go srv.start(ctx)
 	})
 
-	group.GET("/sse/:label", func(ctx *gin.Context) {
+	group.GET("/sse/label/:label", func(ctx *gin.Context) {
 		ctx.Header("connection", "keep-alive")
 
 		labelParam := ctx.Param("label")
@@ -250,6 +308,35 @@ func (srv *Service) BindRoutes(group *gin.RouterGroup) {
 
 		http.ServeFileFS(ctx.Writer, ctx.Request, pagesFS, "pages/labels.html")
 	})
+	
+	group.GET("/sse/chat", func(ctx *gin.Context) {
+		ctx.Header("connection", "keep-alive")
+
+		chatUpdate := srv.ChatBroadcast.Subscribe()
+		defer srv.ChatBroadcast.Cancel(chatUpdate)
+		systemChatUpdate := srv.SystemChatBroadcast.Subscribe()
+		defer srv.SystemChatBroadcast.Cancel(systemChatUpdate)
+		deleteChatUpdate := srv.DeleteChatBroadcast.Subscribe()
+		defer srv.DeleteChatBroadcast.Cancel(deleteChatUpdate)
+
+		ticker := time.NewTicker(10 * time.Millisecond)
+		ctx.Stream(func(w io.Writer) bool {
+			select {
+			case update := <-chatUpdate:
+				ctx.SSEvent("chat", update)
+			case update := <-systemChatUpdate:
+				ctx.SSEvent("system", update)
+			case update := <-deleteChatUpdate:
+				ctx.SSEvent("delete", update)
+			case <-ticker.C:
+			}
+			return true
+		})
+	})
+
+	group.GET("/chat", func(ctx *gin.Context) {
+		http.ServeFileFS(ctx.Writer, ctx.Request, pagesFS, "pages/chat.html")
+	})
 }
 
 func (srv *Service) Run(ctx context.Context) {