add video lifecycle controls

cmd/mxl-player/main.go

@@ -385,6 +385,7 @@ func main() {
 		audioStr  string = args.AudioFlowId
 		showStats bool   = true
 	)
+	videoActive := useVideoSlot
 
 	ctx, cancel := context.WithCancel(context.Background())
 	defer cancel()
@@ -481,22 +482,32 @@ func main() {
 		return fmt.Errorf("reopen: no flow specified")
 	}
 
-	doReconnect := func() {
-		if useVideoSlot {
-			config := playback.FeedConfig{
-				Domain: domainStr,
-				UUID:   videoStr,
-				Active: videoStr != "",
-			}
-			// GUI is the only sender. Replace an older pending command
+	enqueueVideoConfig := func(config playback.FeedConfig) {
 		select {
 		case <-videoCommands:
 		default:
 		}
+
 		select {
 		case videoCommands <- config:
 		default:
 		}
+	}
+
+	doReconnect := func() {
+		if useVideoSlot {
+			videoActive = videoStr != ""
+
+			config := playback.FeedConfig{}
+			if videoStr != "" {
+				config = playback.FeedConfig{
+					Domain: domainStr,
+					UUID:   videoStr,
+					Active: true,
+				}
+			}
+
+			enqueueVideoConfig(config)
 			return
 		}
 		select {
@@ -848,6 +859,45 @@ func main() {
 			if cimgui.Button("Connect") {
 				doReconnect()
 			}
+			if useVideoSlot && videoActive {
+				cimgui.SameLine()
+				if cimgui.Button("Stop video") {
+					videoActive = false
+					enqueueVideoConfig(
+						playback.FeedConfig{
+							Domain: domainStr,
+							UUID:   videoStr,
+							Active: false,
+						})
+				}
+			}
+			if useVideoSlot && !videoActive && videoStr != "" {
+				cimgui.SameLine()
+				if cimgui.Button("Resume video") {
+					videoActive = true
+					enqueueVideoConfig(playback.FeedConfig{
+						Domain: domainStr,
+						UUID:   videoStr,
+						Active: true,
+					})
+				}
+			}
+			if useVideoSlot && videoStr != "" {
+				if cimgui.Button("Remove video") {
+					videoActive = false
+					videoStr = ""
+					enqueueVideoConfig(playback.FeedConfig{})
+				}
+			}
+			if useVideoSlot {
+				if videoActive {
+					cimgui.Text("Video state: active")
+				} else if videoStr != "" {
+					cimgui.Text("Video state: stopped")
+				} else {
+					cimgui.Text("Video state: not configured")
+				}
+			}
 			cimgui.End()
 			gui.EndFrame()
 			lastFrame = time.Now()

imgui.ini

@@ -14,7 +14,7 @@ Size=200,200
 Collapsed=0
 
 [Window][Connection]
-Pos=388,158
-Size=523,141
+Pos=421,219
+Size=518,191
 Collapsed=0