first commit

ws/hub.go

@@ -0,0 +1,66 @@
+package ws
+
+import "sync"
+
+// Client represents a single WebSocket connection.
+// The handler owns the actual *websocket.Conn; the hub only needs the send channel.
+type Client struct {
+	Send chan []byte
+}
+
+// Hub manages all active clients and routes broadcast messages to them.
+type Hub struct {
+	mu         sync.Mutex
+	clients    map[*Client]struct{}
+	Register   chan *Client
+	Unregister chan *Client
+	broadcast  chan []byte
+}
+
+func NewHub() *Hub {
+	return &Hub{
+		clients:    make(map[*Client]struct{}),
+		Register:   make(chan *Client, 8),
+		Unregister: make(chan *Client, 8),
+		broadcast:  make(chan []byte, 512),
+	}
+}
+
+func (h *Hub) Run() {
+	for {
+		select {
+		case c := <-h.Register:
+			h.mu.Lock()
+			h.clients[c] = struct{}{}
+			h.mu.Unlock()
+
+		case c := <-h.Unregister:
+			h.mu.Lock()
+			if _, ok := h.clients[c]; ok {
+				delete(h.clients, c)
+				close(c.Send)
+			}
+			h.mu.Unlock()
+
+		case msg := <-h.broadcast:
+			h.mu.Lock()
+			for c := range h.clients {
+				select {
+				case c.Send <- msg:
+				default:
+					delete(h.clients, c)
+					close(c.Send)
+				}
+			}
+			h.mu.Unlock()
+		}
+	}
+}
+
+// Broadcast sends msg to every connected client (non-blocking).
+func (h *Hub) Broadcast(msg []byte) {
+	select {
+	case h.broadcast <- msg:
+	default:
+	}
+}