fix(app): event ordering

Use a single channel per consumer, instead of one channel per
consumer/event tuple. This ensures that overall ordering of events
remains consistent, and avoids introducing subtle race conditions.

internal/app/integration_helpers_test.go

@@ -9,7 +9,6 @@ import (
 	"log/slog"
 	"net/http"
 	"os"
-	"strconv"
 	"strings"
 	"sync"
 	"testing"
@@ -158,7 +157,6 @@ func sendKey(t *testing.T, screen tcell.SimulationScreen, key tcell.Key, ch rune
 
 	for i := 0; i < maxTries; i++ {
 		if err := screen.PostEvent(tcell.NewEventKey(key, ch, tcell.ModNone)); err != nil {
-			fmt.Printf("Error injecting rune %s, will retry in %s: %s\n", strconv.QuoteRune(ch), waitTime, err)
 			time.Sleep(waitTime)
 		} else {
 			return

internal/event/bus.go

@@ -9,7 +9,7 @@ const defaultChannelSize = 64
 
 // Bus is an event bus.
 type Bus struct {
-	consumers map[Name][]chan Event
+	consumers []chan Event
 	mu        sync.Mutex
 	logger    *slog.Logger
 }
@@ -17,18 +17,17 @@ type Bus struct {
 // NewBus returns a new event bus.
 func NewBus(logger *slog.Logger) *Bus {
 	return &Bus{
-		consumers: make(map[Name][]chan Event),
 		logger: logger,
 	}
 }
 
-// Register registers a consumer for a given event.
+// Register registers a consumer for all events.
-func (b *Bus) Register(name Name) <-chan Event {
+func (b *Bus) Register() <-chan Event {
 	b.mu.Lock()
 	defer b.mu.Unlock()
 
 	ch := make(chan Event, defaultChannelSize)
-	b.consumers[name] = append(b.consumers[name], ch)
+	b.consumers = append(b.consumers, ch)
 	return ch
 }
 
@@ -40,7 +39,7 @@ func (b *Bus) Send(evt Event) {
 	b.mu.Lock()
 	defer b.mu.Unlock()
 
-	for _, ch := range b.consumers[evt.name()] {
+	for _, ch := range b.consumers {
 		select {
 		case ch <- evt:
 		default:

internal/event/bus_test.go

@@ -11,8 +11,8 @@ import (
 func TestBus(t *testing.T) {
 	bus := event.NewBus(testhelpers.NewTestLogger(t))
 
-	ch1 := bus.Register(event.EventNameMediaServerStarted)
+	ch1 := bus.Register()
-	ch2 := bus.Register(event.EventNameMediaServerStarted)
+	ch2 := bus.Register()
 
 	evt := event.MediaServerStartedEvent{
 		RTMPURL:  "rtmp://rtmp.example.com/live",

internal/terminal/terminal.go

@@ -279,15 +279,7 @@ func (ui *UI) C() <-chan domain.Command {
 func (ui *UI) run(ctx context.Context) {
 	defer close(ui.commandC)
 
-	appStateChangedC := ui.eventBus.Register(event.EventNameAppStateChanged)
+	eventC := ui.eventBus.Register()
-	destinationAddedC := ui.eventBus.Register(event.EventNameDestinationAdded)
-	addDestinationFailedC := ui.eventBus.Register(event.EventNameAddDestinationFailed)
-	startDestinationFailedC := ui.eventBus.Register(event.EventNameStartDestinationFailed)
-	destinationRemovedC := ui.eventBus.Register(event.EventNameDestinationRemoved)
-	removeDestinationFailedC := ui.eventBus.Register(event.EventNameRemoveDestinationFailed)
-	existingAppDetectedC := ui.eventBus.Register(event.EventNameOtherInstanceDetected)
-	mediaServerStartedC := ui.eventBus.Register(event.EventNameMediaServerStarted)
-	fatalErrorOccurredC := ui.eventBus.Register(event.EventNameFatalErrorOccurred)
 
 	uiDone := make(chan struct{})
 	go func() {
@@ -302,41 +294,31 @@ func (ui *UI) run(ctx context.Context) {
 
 	for {
 		select {
-		case evt := <-appStateChangedC:
+		case evt := <-eventC:
 			ui.app.QueueUpdateDraw(func() {
-				ui.handleAppStateChanged(evt.(event.AppStateChangedEvent))
+				switch evt := evt.(type) {
-			})
+				case event.AppStateChangedEvent:
-		case evt := <-destinationAddedC:
+					ui.handleAppStateChanged(evt)
-			ui.app.QueueUpdateDraw(func() {
+				case event.DestinationAddedEvent:
-				ui.handleDestinationAdded(evt.(event.DestinationAddedEvent))
+					ui.handleDestinationAdded(evt)
-			})
+				case event.StartDestinationFailedEvent:
-		case evt := <-startDestinationFailedC:
+					ui.handleStartDestinationFailed(evt)
-			ui.app.QueueUpdateDraw(func() {
+				case event.AddDestinationFailedEvent:
-				ui.handleStartDestinationFailed(evt.(event.StartDestinationFailedEvent))
+					ui.handleDestinationEventError(evt.Err)
-			})
+				case event.DestinationRemovedEvent:
-		case evt := <-addDestinationFailedC:
+					ui.handleDestinationRemoved(evt)
-			ui.app.QueueUpdateDraw(func() {
+				case event.RemoveDestinationFailedEvent:
-				ui.handleDestinationEventError(evt.(event.AddDestinationFailedEvent).Err)
+					ui.handleDestinationEventError(evt.Err)
-			})
+				case event.OtherInstanceDetectedEvent:
-		case evt := <-destinationRemovedC:
+					ui.handleOtherInstanceDetected(evt)
-			ui.app.QueueUpdateDraw(func() {
+				case event.MediaServerStartedEvent:
-				ui.handleDestinationRemoved(evt.(event.DestinationRemovedEvent))
+					ui.handleMediaServerStarted(evt)
-			})
+				case event.FatalErrorOccurredEvent:
-		case evt := <-removeDestinationFailedC:
+					ui.handleFatalErrorOccurred(evt)
-			ui.app.QueueUpdateDraw(func() {
+				default:
-				ui.handleDestinationEventError(evt.(event.RemoveDestinationFailedEvent).Err)
+					ui.logger.Warn("unhandled event", "event", evt)
-			})
+				}
-		case evt := <-existingAppDetectedC:
+
-			ui.app.QueueUpdateDraw(func() {
-				ui.handleOtherInstanceDetected(evt.(event.OtherInstanceDetectedEvent))
-			})
-		case evt := <-mediaServerStartedC:
-			ui.app.QueueUpdateDraw(func() {
-				ui.handleMediaServerStarted(evt.(event.MediaServerStartedEvent))
-			})
-		case evt := <-fatalErrorOccurredC:
-			ui.app.QueueUpdateDraw(func() {
-				ui.handleFatalErrorOccurred(evt.(event.FatalErrorOccurredEvent))
 			})
 		case <-ctx.Done():
 			return