From b3e6b7e1b86b1258798aea10d8e23545376383c3 Mon Sep 17 00:00:00 2001
From: DjeAvd <djelal.avdil@master.hes-so.ch>
Date: Thu, 21 May 2026 16:56:24 +0200
Subject: [PATCH] feat(gateway): add battery level support (key 0x05)

- Add KEY_BATTERY constant (0x05)
- Update EXPECTED_PAYLOAD_SIZE from 12 to 14 bytes
- Decode battery level from payload
- Publish battery field in MQTT JSON payload
---
 gateway/gateway.py | 11 +++++++++--
 1 file changed, 9 insertions(+), 2 deletions(-)

diff --git a/gateway/gateway.py b/gateway/gateway.py
index 5258b95..4280de2 100644
--- a/gateway/gateway.py
+++ b/gateway/gateway.py
@@ -23,13 +23,14 @@ class Gateway:
     KEY_HUMIDITY = 0x02
     KEY_TEMP     = 0x03
     KEY_CO2      = 0x04
+    KEY_BATTERY  = 0x05  # Battery level (1 byte, integer %)
 
     # Sentinel value indicating sensor failure or not ready
     INVALID_VALUE = 0xFFFFFFFF
 
     # Expected payload size in bytes:
-    # 4 keys (1B each) + window(1B) + humidity(1B) + temp(2B) + co2(4B) = 12 bytes
-    EXPECTED_PAYLOAD_SIZE = 12
+    # 5 keys (1B each) + window(1B) + humidity(1B) + temp(2B) + co2(4B) + battery(1B) = 14 bytes
+    EXPECTED_PAYLOAD_SIZE = 14
 
     def __init__(self, config: dict):
         self.gateway_id  = config["gateway_id"]
@@ -88,6 +89,7 @@ class Gateway:
           0x02 : humidity (1 byte, integer %)
           0x03 : temperature (2 bytes big-endian, integer / 10 = degrees C)
           0x04 : CO2 ppm (4 bytes big-endian, integer)
+          0x05 : battery level (1 byte, integer %)
 
         Values equal to 0xFFFFFFFF indicate sensor failure or not ready
         and are discarded.
@@ -117,6 +119,9 @@ class Gateway:
                 else:
                     log.debug(f"CO2 sensor not ready — discarding value 0xFFFFFFFF")
                 i += 4
+            elif key == self.KEY_BATTERY and i < len(data):
+                result["battery"] = data[i]
+                i += 1
             else:
                 # Unknown key — likely a non-Thingy device, ignore silently
                 log.debug(f"Unknown key 0x{key:02x} at offset {i-1}")
@@ -139,6 +144,8 @@ class Gateway:
             payload["co2_ppm"] = data["co2_ppm"]
         if "window_open" in data:
             payload["window_open"] = data["window_open"]
+        if "battery" in data:
+            payload["battery"] = data["battery"]
 
         self.mqttc.publish(topic, json.dumps(payload))
         log.info(f"Published to {topic} : {payload}")