deskcontrol/src/main.cpp

/**
 * \brief Entry point
 * 
 * Deskcontrol is a simple on/off timer switch inteded for use with an ATX PSU.
 * The theory of operation is turning on and off power by pulling the control line low/high while 
 * running of the 5V standby line.
 * 
 * Additional features include support for a DHT11 to log the temperature.
 * \file
 */

#include "config.h"

#include <Homie.h>

#include <LoggerNode.h>
LoggerNode LN; ///<Instance of the LoggerNode library

#include "DHTesp.h"
DHTesp dht; ///< DHT instance 


#define OUTPUT_SET(x)  digitalWrite(CONFIG_IO_RELAY, x ? LOW : HIGH)
unsigned int timer = 0;
unsigned int next_timer_update = 0;
HomieNode powerNode("power", "Power", "switch");
HomieNode temperatureNode("temperature", "Temperature", "temperature");

/** Power state handler 
 * Handes event on the power state MQTT node
 */
bool powerStateHandler(const HomieRange& range, const String& value)
{
    if (value != "on" && value != "off") 
    {
      return false;
    }
    powerNode.setProperty("state").send(value);
    powerNode.setProperty("timer").send("0");
    timer = 0;

    if(value == "on")
    {
      OUTPUT_SET(true);
      LN.logf(__PRETTY_FUNCTION__, LoggerNode::INFO, "Power ON");
    }
    else
    {
      OUTPUT_SET(false); LN.logf(__PRETTY_FUNCTION__, LoggerNode::INFO, "Power OFF");
    }
    
    return true;
}

/**
 * Handler for events on the powerTimer node
 */
bool powerTimerHandler(const HomieRange& range, const String& value)
{
    int settimer = value.toInt();
    if(settimer == 0 || settimer > 120) 
         return false;

    timer = millis() + (settimer * 1000 * 60);
    next_timer_update = millis() + 60*1000;
    powerNode.setProperty("timer").send(String(settimer));
    powerNode.setProperty("state").send("on");
    LN.logf(__PRETTY_FUNCTION__, LoggerNode::INFO, "Power on for %d minutes", settimer);
    OUTPUT_SET(true);
    return true;
}


void setupHandler()
{

  pinMode(CONFIG_IO_RELAY, OUTPUT);
  OUTPUT_SET(false);
  powerNode.setProperty("state").send("off");
  powerNode.setProperty("timer").send("0");

  dht.setup(CONFIG_IO_DHT11, DHTesp::DHT11); // Connect DHT sensor to GPIO 17
}

void loopHandleTimer() 
{
  if(timer)
  {
    if(timer < millis()) 
    { //Timer has expired. (Ignore the wraparound...)
      timer = 0;
      OUTPUT_SET(false);
      powerNode.setProperty("timer").send("0");
      powerNode.setProperty("state").send("off");
    }

    if(next_timer_update && millis() > next_timer_update)
    {
      next_timer_update = millis() + 60*1000;
      unsigned int time_remaining = timer - millis();
      unsigned int min_left = time_remaining / (60*1000);
      powerNode.setProperty("timer").send(String(min_left));
    }
  }
}

void loopHandleTemperature() 
{
  static unsigned long lastTemperatureSent = 0;
  if (millis() - lastTemperatureSent >= CONFIG_TEMPERATURE_SEND_INTERVAL * 1000UL || lastTemperatureSent == 0)
  {
    float humidity = dht.getHumidity();
    float temperature = dht.getTemperature();
    LN.logf(__PRETTY_FUNCTION__, LoggerNode::DEBUG, "Temperature: %f C Humidity: %f", temperature, humidity);
    temperatureNode.setProperty("temperature").send(String(temperature));
    temperatureNode.setProperty("humidity").send(String(humidity));
    lastTemperatureSent = millis();
  }
}

/**
 * Main event loop
 * \callgraph
 */
void loopHandler()
{
  loopHandleTimer();
  loopHandleTemperature();
}

void setup()
{

    Homie_setFirmware("deskcontrol", VERSION);
    Homie.setLoggingPrinter(&Serial);
    Serial.begin(CONFIG_SERIAL_BAUDRATE);

    Homie.disableResetTrigger();

    //Power
    powerNode.advertise("state").settable(powerStateHandler);
    powerNode.advertise("timer").settable(powerTimerHandler);

    //Temperature
    temperatureNode.advertise("humidity");
    temperatureNode.advertise("temperature");

    Homie.setSetupFunction(setupHandler);
    Homie.setLoopFunction(loopHandler);

    Homie.setup();
}

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