Update App version to 0.1.1

Signed-off-by: luckfox-eng29 <eng29@luckfox.com>

stream_broadcaster.go

@@ -0,0 +1,59 @@
+package kvm
+
+import (
+	"sync"
+
+	"github.com/google/uuid"
+)
+
+type VideoBroadcaster struct {
+	subscribers map[string]chan []byte
+	lock        sync.RWMutex
+	onFirstSubscribe func()
+	onLastUnsubscribe func()
+}
+
+var videoBroadcaster = &VideoBroadcaster{
+	subscribers: make(map[string]chan []byte),
+}
+
+func (b *VideoBroadcaster) Subscribe() (string, chan []byte) {
+	b.lock.Lock()
+	defer b.lock.Unlock()
+	id := uuid.New().String()
+	// Buffer a bit to avoid dropping frames too easily, 
+	// but not too much to avoid latency build-up
+	ch := make(chan []byte, 200) 
+	wasEmpty := len(b.subscribers) == 0
+	b.subscribers[id] = ch
+	if wasEmpty && b.onFirstSubscribe != nil {
+		b.onFirstSubscribe()
+	}
+	return id, ch
+}
+
+func (b *VideoBroadcaster) Unsubscribe(id string) {
+	b.lock.Lock()
+	defer b.lock.Unlock()
+	if ch, ok := b.subscribers[id]; ok {
+		close(ch)
+		delete(b.subscribers, id)
+		if len(b.subscribers) == 0 && b.onLastUnsubscribe != nil {
+			b.onLastUnsubscribe()
+		}
+	}
+}
+
+func (b *VideoBroadcaster) Broadcast(data []byte) {
+	b.lock.RLock()
+	defer b.lock.RUnlock()
+	for _, ch := range b.subscribers {
+		// Non-blocking send
+		select {
+		case ch <- data:
+		default:
+			// Drop frame if channel is full to avoid blocking other subscribers
+			// Ideally we should have a ring buffer or similar, but this is simple
+		}
+	}
+}