Add EVS control portal, io_mode switching, and DAC-only speaker path

bridge/README.md

@@ -9,6 +9,7 @@ It provides:
 - Optional Home Assistant webhook callbacks (`connected`, `start`, `stop`, `disconnected`)
 - VAD auto-segmentation (`vad_segment`) with pre-roll/post-roll
 - Optional STT worker (`vad_segment` -> `transcript`) via MQTT
+- Optional 1:1 device pairing (`mic_device -> speaker_device`) for echo routing
 
 ## 1) Start the bridge
 
@@ -47,6 +48,11 @@ In `include/secrets.h`:
 - set bridge host
 - set WS port/path
 - set unique `EVS_DEVICE_ID`
+- set runtime IO mode:
+  - `EVS_DEFAULT_IO_MODE "mic"` for microphone device
+  - `EVS_DEFAULT_IO_MODE "spk"` for speaker device
+- set DAC output pin on speaker device:
+  - `EVS_SPK_DAC_PIN 25` or `26`
 
 Then upload firmware.
 
@@ -160,6 +166,7 @@ services:
       MQTT_BASE_TOPIC: "evs"
       MQTT_TTS_TOPIC: "evs/+/play_pcm16le"
       MQTT_STATUS_RETAIN: "true"
+      DEVICE_PAIR_MAP: '{"esp32-evs-1-mic":"esp32-evs-1-spk"}'
       HA_WEBHOOK_URL: ""
       SAVE_SESSIONS: "true"
       SESSIONS_DIR: "/data/sessions"

bridge/app.py

@@ -41,6 +41,7 @@ MQTT_PASSWORD = os.getenv("MQTT_PASSWORD", "")
 MQTT_BASE_TOPIC = os.getenv("MQTT_BASE_TOPIC", "evs")
 MQTT_TTS_TOPIC = os.getenv("MQTT_TTS_TOPIC", f"{MQTT_BASE_TOPIC}/+/play_pcm16le")
 MQTT_STATUS_RETAIN = getenv_bool("MQTT_STATUS_RETAIN", True)
+DEVICE_PAIR_MAP_JSON = os.getenv("DEVICE_PAIR_MAP", "").strip()
 
 HA_WEBHOOK_URL = os.getenv("HA_WEBHOOK_URL", "").strip()
 SAVE_SESSIONS = getenv_bool("SAVE_SESSIONS", True)
@@ -125,6 +126,21 @@ class BridgeState:
 
 
 state = BridgeState()
+DEVICE_PAIR_MAP: Dict[str, str] = {}
+if DEVICE_PAIR_MAP_JSON:
+    try:
+        raw = json.loads(DEVICE_PAIR_MAP_JSON)
+        if isinstance(raw, dict):
+            DEVICE_PAIR_MAP = {str(k): str(v) for k, v in raw.items() if str(k) and str(v)}
+            log.info("device pair map loaded: %s", DEVICE_PAIR_MAP)
+        else:
+            log.warning("DEVICE_PAIR_MAP must be a JSON object")
+    except Exception:
+        log.exception("failed to parse DEVICE_PAIR_MAP")
+
+
+def paired_output_device(device_id: str) -> str:
+    return DEVICE_PAIR_MAP.get(device_id, device_id)
 
 
 def build_metrics(device_id: str, session: DeviceSession) -> dict:
@@ -408,14 +424,16 @@ async def handle_text_message(device_id: str, session: DeviceSession, raw: str)
             "peak": msg.get("peak", 0),
             "avg_abs": msg.get("avg_abs", 0),
             "samples": msg.get("samples", 0),
+            "mic_gain": msg.get("mic_gain", 0),
         }
         state.publish_status(device_id, payload)
         log.info(
-            "mic_level: device=%s peak=%s avg_abs=%s samples=%s",
+            "mic_level: device=%s peak=%s avg_abs=%s samples=%s mic_gain=%s",
             device_id,
             payload["peak"],
             payload["avg_abs"],
             payload["samples"],
+            payload["mic_gain"],
         )
         return
 
@@ -437,7 +455,10 @@ async def handle_binary_message(device_id: str, session: DeviceSession, data: by
                 drop = len(session.pcm_bytes) - MAX_SESSION_BYTES
                 del session.pcm_bytes[:drop]
     if ECHO_ENABLED:
-        await session.ws.send(data)
+        target_device = paired_output_device(device_id)
+        ok = await state.send_binary_to_device(target_device, data)
+        if not ok and target_device != device_id:
+            log.debug("paired output device not connected: src=%s target=%s", device_id, target_device)
 
 
 def parse_device_id(path: str) -> str: