Things/things/things.ino

#include <Homie.h>  // https://github.com/marvinroger/homie-esp8266
#include <DHT.h>    // https://github.com/adafruit/DHT-sensor-library

#include "DeviceLed.h"
#include "DeviceLdr.h"

#define HAS_LDR
#define HAS_LED
#undef HAS_DHT

// HAS_LED
#define PIN_LED_RED D8
#define PIN_LED_GREEN D6
#define PIN_LED_BLUE D7
DeviceLed deviceLed(PIN_LED_RED, PIN_LED_GREEN, PIN_LED_BLUE);

// HAS_LDR
#define PIN_LDR A0
DeviceLdr deviceLdr(PIN_LDR);

// HAS_DHT
#define PIN_DHT D4
#define TYPE_DHT DHT22
HomieNode humidityNode("humidity", "humidity");
HomieNode temperatureNode("temperature", "temperature");
HomieNode heatindexNode("heatindex", "heatindex");
const int INTERVAL_DHT = 60;
unsigned long lastSentDHT = 0;
DHT dht(PIN_DHT, TYPE_DHT);
float humidity, temperature;  // raw values from the sensor
float heatindex;              // computed value from the sensor

void setupHandler() {
  #ifdef HAS_LDR
    deviceLdr.setup();
  #endif
  #ifdef HAS_LED
    deviceLed.setup();
  #endif
  #ifdef HAS_DHT
    dht.begin();
  #endif
}

// compare float values
bool isEqual(float a, float b, float epsilon=0.001) {
  return fabs(a - b) <= epsilon * fabs(a);
}

void loopHandlerDHT() {
  if (millis() - lastSentDHT >= INTERVAL_DHT * 1000UL || lastSentDHT == 0) {
    float previousHumidity = humidity;
    float previousTemperature = temperature;
    float previousHeatindex = heatindex;
    humidity = dht.readHumidity();        // read humidity as a percent
    temperature = dht.readTemperature();  // read temperature as Celsius
    heatindex = dht.computeHeatIndex(temperature, humidity, false);

    // check if any reads failed and exit early
    if (isnan(humidity) || isnan(temperature)) {
      Serial.println("Failed to read from DHT sensor!");
      return;
    }

    if (!isEqual(humidity, previousHumidity)) {
      Serial.print("humidity: ");
      Serial.println(humidity);
      if (!Homie.setNodeProperty(humidityNode, "value", String(humidity), true)) {
        Serial.println("Sending failed");
      }
    } else {
      Serial.println("humidity unchanged");
    }

    if (!isEqual(temperature, previousTemperature)) {
      Serial.print("temperature: ");
      Serial.println(temperature);
      if (!Homie.setNodeProperty(temperatureNode, "value", String(temperature), true)) {
        Serial.println("Sending failed");
      }
    } else {
      Serial.println("temperature unchanged");
    }

    if (!isEqual(heatindex, previousHeatindex)) {
      Serial.print("heatindex: ");
      Serial.println(heatindex);
      if (!Homie.setNodeProperty(heatindexNode, "value", String(heatindex), true)) {
        Serial.println("Sending failed");
      }
    } else {
      Serial.println("heatindex unchanged");
    }

    lastSentDHT = millis();
  }
}

void loopHandler() {
  #ifdef HAS_LDR
  deviceLdr.loop();
  #endif
  #ifdef HAS_LED
  deviceLed.loop();
  #endif
  #ifdef HAS_DHT
  loopHandlerDHT();
  #endif
}

void setup() {
  Homie.setFirmware("things", "1.0.0");
  #ifdef HAS_LDR
  deviceLdr.homieRegister();
  #endif
  #ifdef HAS_LED
  deviceLed.homieRegister();
  #endif
  #ifdef HAS_DHT
  Homie.registerNode(humidityNode);
  Homie.registerNode(temperatureNode);
  Homie.registerNode(heatindexNode);
  #endif
  Homie.setSetupFunction(setupHandler);
  Homie.setLoopFunction(loopHandler);
  Homie.setup();
}

void loop() {
  Homie.loop();
}