#define TEMP_SENSOR_PIN 14
#define HUMIDITY_SENSOR_PIN 14
#define FAN_PIN 15
#define CO2_PIN 16
#define ULTRASONIC_PIN 17

#define CHECK_FREQUENCY 1      // check sensors every second
#define HUMIDITY_DESIRED 75
#define HUMIDITY_VARIATION 3   // ultrasonic turns on at (75 - 3 = 72) and off
                               // at (75 + 3 = 78)


// Tempature + Humidity Sensor
#include <Adafruit_Sensor.h>
#include <DHT.h>
#include <DHT_U.h>
#define DHTTYPE DHT11
#define DHTPIN TEMP_SENSOR_PIN
DHT_Unified dht(DHTPIN, DHTTYPE);

int get_humidity () {
  // Get temperature event and print its value.
  sensors_event_t event;
  dht.temperature().getEvent(&event);
  if (isnan(event.temperature)) {
    Serial.println(F("Error reading temperature!"));
  }
  else {
    return event.temperature;
    /* Serial.print(F("Temperature: ")); */
    /* Serial.print(event.temperature); */
    /* Serial.println(F("°C")); */
  }
}

int get_tempature () {
  sensors_event_t event;
  // Get humidity event and print its value.
  dht.humidity().getEvent(&event);
  if (isnan(event.relative_humidity)) {
    Serial.println(F("Error reading humidity!"));
  }
  else {
    return event.relative_humidity;
    /* Serial.print(F("Humidity: ")); */
    /* Serial.print(event.relative_humidity); */
    /* Serial.println(F("%")); */
  }
}

int get_co2 () { ; }
bool start_ultrasonic () { ; }
bool stop_ultrasonic () { ; }
bool start_fan () { ; }
bool stop_fan () { ; }


bool log ( int humidity, int temp, int co2 ) {
  Serial.printf("Tempature: %d\tHumidity: %d\tCO2: %d\n",
                humidity, temp, co2);
}

void setup () {
  Serial.begin(115200);
  dht.begin();                  /* temp/humidity sensor */
}

void loop() {
  delay(CHECK_FREQUENCY * 1000);
  int humidity = get_humidity();
  int temp = get_tempature();
  int co2 = get_co2();

  if ( humidity < (HUMIDITY_DESIRED - HUMIDITY_VARIATION) ) {
    start_ultrasonic();
    stop_fan();
  } else if ( humidity > (HUMIDITY_DESIRED + HUMIDITY_VARIATION) ) {
    start_fan();
    stop_ultrasonic();
  } else {
    ; // keep doing the same
  }

  log(humidity, temp, co2);
}