Merge pull request wled#5489 from wled/copilot/fix-wled-discovery-issues

Fix Alexa/Hue discovery by correcting SSDP response to match UPnP spec

Author: netmindz

wled00/src/dependencies/espalexa/Espalexa.h

@@ -85,6 +85,7 @@ class Espalexa {
   IPAddress ipMulti;
   uint32_t mac24; //bottom 24 bits of mac
   String escapedMac=""; //lowercase mac address
+  String bridgeId="";   //uppercase EUI-64 bridge ID (16 hex chars)
 
   //private member functions
   const char* modeString(EspalexaColorMode m)
@@ -297,13 +298,13 @@ class Espalexa {
 
     snprintf_P(buf, sizeof(buf), PSTR("HTTP/1.1 200 OK\r\n"
       "EXT:\r\n"
-      "CACHE-CONTROL: max-age=100\r\n" // SSDP_INTERVAL
+      "CACHE-CONTROL: max-age=86400\r\n" // SSDP_INTERVAL
       "LOCATION: http://%s:80/description.xml\r\n"
       "SERVER: FreeRTOS/6.0.5, UPnP/1.0, IpBridge/1.17.0\r\n" // _modelName, _modelNumber
       "hue-bridgeid: %s\r\n"
-      "ST: urn:schemas-upnp-org:device:basic:1\r\n"  // _deviceType
-      "USN: uuid:2f402f80-da50-11e1-9b23-%s::upnp:rootdevice\r\n" // _uuid::_deviceType
-      "\r\n"),s,escapedMac.c_str(),escapedMac.c_str());
+      "ST: urn:schemas-upnp-org:device:Basic:1\r\n"  // _deviceType
+      "USN: uuid:2f402f80-da50-11e1-9b23-%s::urn:schemas-upnp-org:device:Basic:1\r\n" // _uuid::_deviceType
+      "\r\n"),s,bridgeId.c_str(),escapedMac.c_str());
 
     espalexaUdp.beginPacket(espalexaUdp.remoteIP(), espalexaUdp.remotePort());
     #ifdef ARDUINO_ARCH_ESP32
@@ -333,6 +334,11 @@ class Espalexa {
     escapedMac.replace(":", "");
     escapedMac.toLowerCase();
 
+    // Compute EUI-64 bridge ID from MAC-48: insert standard "FFFE" padding between
+    // the first 6 hex chars (OUI/manufacturer) and last 6 hex chars (device), then uppercase
+    bridgeId = escapedMac.substring(0, 6) + "fffe" + escapedMac.substring(6);
+    bridgeId.toUpperCase();
+
     String macSubStr = escapedMac.substring(6, 12);
     mac24 = strtol(macSubStr.c_str(), 0, 16);