From fb21dec0ed0bff50db7248be626e38e819967ecf Mon Sep 17 00:00:00 2001
From: Jan Svabenik <jan@svabi.ch>
Date: Sun, 5 Apr 2026 18:00:59 +0200
Subject: [PATCH] Expose queue stats via status endpoint

---
 docs/API.md                             | 12 +++++++--
 docs/pro-runtime-hardening-workboard.md |  2 ++
 internal/control/control.go             |  3 +++
 internal/control/control_test.go        | 36 +++++++++++++++++++++++++
 4 files changed, 51 insertions(+), 2 deletions(-)

diff --git a/docs/API.md b/docs/API.md
index 78e0122..bd51eb2 100644
--- a/docs/API.md
+++ b/docs/API.md
@@ -19,7 +19,7 @@ Health check.
 
 ### `GET /status`
 
-Current transmitter status (read-only snapshot).
+Current transmitter status (read-only snapshot). Runtime indicator, alert, and queue stats from the running TX controller are mirrored here for quick health checks.
 
 **Response:**
 ```json
@@ -31,7 +31,15 @@ Current transmitter status (read-only snapshot).
   "rdsEnabled": true,
   "preEmphasisTauUS": 50,
   "limiterEnabled": true,
-  "fmModulationEnabled": true
+  "fmModulationEnabled": true,
+  "runtimeIndicator": "normal",
+  "runtimeAlert": "",
+  "queue": {
+    "capacity": 3,
+    "depth": 1,
+    "fillLevel": 0.33,
+    "health": "low"
+  }
 }
 ```
 
diff --git a/docs/pro-runtime-hardening-workboard.md b/docs/pro-runtime-hardening-workboard.md
index 6854400..e2cd6af 100644
--- a/docs/pro-runtime-hardening-workboard.md
+++ b/docs/pro-runtime-hardening-workboard.md
@@ -250,6 +250,7 @@ Generator/Upsampler und Hardwarewriter werden als getrennte Stufen mit kleinem,
 | 2026-04-05 | Queue-Health-Indikator | `QueueStats.Health` gibt `critical`/`low`/`normal` zurück und `txBridge` leitet `EngineStats.Queue` ins `/runtime`-JSON. |
 | 2026-04-05 | Runtime-Indikator | `EngineStats.RuntimeIndicator` kombiniert `queue.health` + `lateBuffers`, `/runtime` zeigt `engine.runtimeIndicator`. |
 | 2026-04-05 | /status runtime indicator | `/status` reuses `txBridge.TXStats()` and now reports `runtimeIndicator` alongside the config snapshot for quick ops. |
+| 2026-04-05 | /status queue stats | `/status` spiegelt das `queue`-Objekt aus `txBridge.TXStats()` für schnelle Queue-Checks, API-Doku und `TestStatusReportsQueueStats` fangen den neuen Key ab. |
 
 ## WS-01 Verifikation
 | Datum | Fokus | Ergebnis |
@@ -259,6 +260,7 @@ Generator/Upsampler und Hardwarewriter werden als getrennte Stufen mit kleinem,
 | 2026-04-05 | Runtime-Indikator | OK `go test ./...` deckt `runtimeIndicator` sowie `/runtime`-Exposition von `engine.runtimeIndicator`. |
 | 2026-04-05 | Runtime API queue health | ✅ `/runtime` liefert jetzt `engine.queue.health` dank `txBridge.TXStats`. |
 | 2026-04-05 | /status runtime indicator | ✅ `/status` gibt jetzt `runtimeIndicator` aus (`control_test` deckt den neuen Key). |
+| 2026-04-05 | /status queue stats | ✅ `TestStatusReportsQueueStats` plus `docs/API.md` zeigen, dass `queue` korrekt durchgereicht wird. |
 
 ---
 
diff --git a/internal/control/control.go b/internal/control/control.go
index 278ec6a..823a8af 100644
--- a/internal/control/control.go
+++ b/internal/control/control.go
@@ -140,6 +140,9 @@ func (s *Server) handleStatus(w http.ResponseWriter, _ *http.Request) {
 			if alert, ok := stats["runtimeAlert"]; ok {
 				status["runtimeAlert"] = alert
 			}
+			if queue, ok := stats["queue"]; ok {
+				status["queue"] = queue
+			}
 		}
 	}
 
diff --git a/internal/control/control_test.go b/internal/control/control_test.go
index 1a70684..93fc508 100644
--- a/internal/control/control_test.go
+++ b/internal/control/control_test.go
@@ -9,6 +9,7 @@ import (
 	"testing"
 
 	cfgpkg "github.com/jan/fm-rds-tx/internal/config"
+	"github.com/jan/fm-rds-tx/internal/output"
 )
 
 func TestHealthz(t *testing.T) {
@@ -55,6 +56,41 @@ func TestStatusReportsRuntimeIndicator(t *testing.T) {
 	}
 }
 
+func TestStatusReportsQueueStats(t *testing.T) {
+	cfg := cfgpkg.Default()
+	queueStats := output.QueueStats{
+		Capacity:  cfg.Runtime.FrameQueueCapacity,
+		Depth:     1,
+		FillLevel: 0.25,
+		Health:    output.QueueHealthLow,
+	}
+	srv := NewServer(cfg)
+	srv.SetTXController(&fakeTXController{stats: map[string]any{"queue": queueStats}})
+	rec := httptest.NewRecorder()
+	srv.Handler().ServeHTTP(rec, httptest.NewRequest(http.MethodGet, "/status", nil))
+	if rec.Code != 200 {
+		t.Fatalf("status: %d", rec.Code)
+	}
+	var body map[string]any
+	if err := json.Unmarshal(rec.Body.Bytes(), &body); err != nil {
+		t.Fatalf("unmarshal queue stats: %v", err)
+	}
+	queueRaw, ok := body["queue"]
+	if !ok {
+		t.Fatalf("missing queue in status")
+	}
+	queueMap, ok := queueRaw.(map[string]any)
+	if !ok {
+		t.Fatalf("queue stats type mismatch: %T", queueRaw)
+	}
+	if queueMap["capacity"] != float64(queueStats.Capacity) {
+		t.Fatalf("queue capacity mismatch: want %v got %v", queueStats.Capacity, queueMap["capacity"])
+	}
+	if queueMap["health"] != string(queueStats.Health) {
+		t.Fatalf("queue health mismatch: want %s got %v", queueStats.Health, queueMap["health"])
+	}
+}
+
 func TestDryRunEndpoint(t *testing.T) {
 	srv := NewServer(cfgpkg.Default())
 	rec := httptest.NewRecorder()