From 52c36ef6a4fe1ceefeeab14ff1c86a7772c22460 Mon Sep 17 00:00:00 2001
From: Hermann Kraus <hermr2d2+git@gmail.com>
Date: Thu, 20 Jan 2022 00:26:07 +0100
Subject: [PATCH] Add Home Assisant MQTT autodiscovery for usermod multi_relay.

---
 usermods/multi_relay/readme.md             |  2 +-
 usermods/multi_relay/usermod_multi_relay.h | 53 ++++++++++++++++++++--
 2 files changed, 49 insertions(+), 6 deletions(-)

diff --git a/usermods/multi_relay/readme.md b/usermods/multi_relay/readme.md
index ebf2056a8..267bb54a8 100644
--- a/usermods/multi_relay/readme.md
+++ b/usermods/multi_relay/readme.md
@@ -36,7 +36,7 @@ wled/deviceMAC/relay/0 on|off
 
 1. Register the usermod by adding `#include "../usermods/multi_relay/usermod_multi_relay.h"` at the top and `usermods.add(new MultiRelay());` at the bottom of `usermods_list.cpp`.
 or
-2. Use `#define USERMOD_MULTI_RELAY` in wled.h or `-D USERMOD_MULTI_RELAY`in your platformio.ini
+2. Use `#define USERMOD_MULTI_RELAY` in wled.h or `-D USERMOD_MULTI_RELAY` in your platformio.ini
 
 You can override the default maximum number (4) of relays by defining MULTI_RELAY_MAX_RELAYS.
 
diff --git a/usermods/multi_relay/usermod_multi_relay.h b/usermods/multi_relay/usermod_multi_relay.h
index 9a92d4e22..9073051b0 100644
--- a/usermods/multi_relay/usermod_multi_relay.h
+++ b/usermods/multi_relay/usermod_multi_relay.h
@@ -55,12 +55,12 @@ class MultiRelay : public Usermod {
     static const char _button[];
 
 
-    void publishMqtt(const char* state, int relay) {
+    void publishMqtt(int relay) {
       //Check if MQTT Connected, otherwise it will crash the 8266
       if (WLED_MQTT_CONNECTED){
         char subuf[64];
         sprintf_P(subuf, PSTR("%s/relay/%d"), mqttDeviceTopic, relay);
-        mqtt->publish(subuf, 0, false, state);
+        mqtt->publish(subuf, 0, false, _relay[relay].state ? "on" : "off");
       }
     }
 
@@ -105,7 +105,7 @@ class MultiRelay : public Usermod {
             for (int i=0; i<MULTI_RELAY_MAX_RELAYS; i++) {
               int value = getValue(p->value(), ',', i);
               if (value==-1) {
-                error = F("There must be as much arugments as relays");
+                error = F("There must be as many arguments as relays");
               } else {
                 // Switch
                 if (_relay[i].external) switchRelay(i, (bool)value);
@@ -118,7 +118,7 @@ class MultiRelay : public Usermod {
             for (int i=0;i<MULTI_RELAY_MAX_RELAYS;i++) {
               int value = getValue(p->value(), ',', i);
               if (value==-1) {
-                error = F("There must be as mutch arugments as relays");
+                error = F("There must be as many arguments as relays");
               } else {
                 // Toggle
                 if (value && _relay[i].external) toggleRelay(i);
@@ -199,7 +199,7 @@ class MultiRelay : public Usermod {
       _relay[relay].state = mode;
       pinMode(_relay[relay].pin, OUTPUT);
       digitalWrite(_relay[relay].pin, mode ? !_relay[relay].mode : _relay[relay].mode);
-      publishMqtt(mode ? "on" : "off", relay);
+      publishMqtt(relay);
     }
 
     /**
@@ -252,6 +252,49 @@ class MultiRelay : public Usermod {
         strcpy(subuf, mqttDeviceTopic);
         strcat_P(subuf, PSTR("/relay/#"));
         mqtt->subscribe(subuf, 0);
+        publishHomeAssistantAutodiscovery();
+        for (uint8_t i=0; i<MULTI_RELAY_MAX_RELAYS; i++) {
+            publishMqtt(i); //publish current state
+        }
+      }
+    }
+
+    void publishHomeAssistantAutodiscovery() {
+      for (uint8_t i = 0; i < MULTI_RELAY_MAX_RELAYS; i++) {
+        char uid[16], json_str[1024], buf[128];
+        size_t payload_size;
+        sprintf(uid, "%s_sw%d", escapedMac.c_str(), i);
+
+        if (_relay[i].pin >= 0 && _relay[i].external) {
+          StaticJsonDocument<1024> json;
+          sprintf(buf, "%s Switch %d", serverDescription, i); //max length: 33 + 8 + 3 = 44
+          json[F("name")] = buf;
+
+          sprintf(buf, "%s/relay/%d", mqttDeviceTopic, i); //max length: 33 + 7 + 3 = 43
+          json["~"] = buf;
+          strcat(buf, "/command");
+          mqtt->subscribe(buf, 0);
+
+          json[F("stat_t")] = "~";
+          json[F("cmd_t")] = "~/command";
+          json[F("pl_off")] = F("off");
+          json[F("pl_on")] = F("on");
+          json[F("uniq_id")] = uid;
+
+          strcpy(buf, mqttDeviceTopic); //max length: 33 + 7 = 40
+          strcat(buf, "/status");
+          json[F("avty_t")] = buf;
+          json[F("pl_avail")] = F("online");
+          json[F("pl_not_avail")] = F("offline");
+          //TODO: dev
+          payload_size = serializeJson(json, json_str);
+        } else {
+          //Unpublish disabled or internal relays
+          json_str[0] = 0;
+          payload_size = 0;
+        }
+        sprintf(buf, "homeassistant/switch/%s/config", uid);
+        mqtt->publish(buf, 0, true, json_str, payload_size);
       }
     }