#include "DHT.h"
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define OLED_RESET -1
#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels
#define DHTPIN 2 // what pin we're connected to
//#define DHTTYPE DHT11 // DHT 11
#define DHTTYPE DHT22 // DHT 22 (AM2302)
//#define DHTTYPE DHT21 // DHT 21 (AM2301)

int greenPin = 6;
int yellowPin = 7;
int redPin = 8;
DHT dht(DHTPIN, DHTTYPE);
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

void setup() {
  Serial.begin(9600);
  Serial.println("DHTxx test!");
  dht.begin();
  pinMode(greenPin, OUTPUT);
  pinMode(yellowPin, OUTPUT);
  pinMode(redPin, OUTPUT);
  display.begin(SSD1306_SWITCHCAPVCC, 0x3c); //initialize I2C addr 0x3c
}
void loop() {
  float h = dht.readHumidity();
  float t = dht.readTemperature();
  // check if returns are valid, if they are NaN (not a number) then something went wrong!
  if (isnan(t) || isnan(h)) {
    Serial.println("Failed to read from DHT");
  } else {
    Serial.print("Humidity: ");
    Serial.print(h);
    Serial.print(" %\t");
    Serial.print("Temperature: ");
    Serial.print(t);
    Serial.println(" *C");
    digitalWrite(greenPin, LOW);
    digitalWrite(yellowPin, LOW);
    digitalWrite(redPin, LOW);
    
    if (t < 25) {
      digitalWrite(greenPin, HIGH);
    }
    else if (t <= 30) {
      digitalWrite(yellowPin, HIGH);
    }
    else {
      digitalWrite(redPin, HIGH);
    }

    display.clearDisplay();
    display.setCursor(0, 0);
    display.setTextSize(1);
    display.setTextColor(WHITE);
    display.print("Humidity: ");
    display.println(h);
    display.print("Temperature: ");
    display.println(t);
    display.display();
  }
  delay(500);
}