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

#define DHTPIN 7      
#define DHTTYPE DHT22  
DHT dht(DHTPIN, DHTTYPE); 
#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define OLED_RESET     -1
#define SSD1306_I2C_ADDRESS 0x3C 

Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);

float hum;  
float temp; 
const int HigherTemp = 27; 
const int LowerTemp = 15;  

enum State {
  Red,
  Green,
  Blue
};


State currentState ;
const int LED1_Red = 2;    
const int LED2_Blue = 4;   
const int LED3_Green = 3; 

void setup() {
  Serial.begin(9600);
  pinMode(LED1_Red, OUTPUT);
  pinMode(LED2_Blue, OUTPUT);
  pinMode(LED3_Green, OUTPUT);

  dht.begin();
    Wire.begin();
  if (!display.begin(SSD1306_SWITCHCAPVCC, SSD1306_I2C_ADDRESS)) {
    Serial.println(F("SSD1306 allocation failed"));
    for(;;); 
  }
  display.display();
}

void loop() {
  hum = dht.readHumidity();
  temp = dht.readTemperature();
  display.clearDisplay();
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.setCursor(0, 0);
  display.println(temp);
  display.display();

  if (temp >= LowerTemp && temp <= HigherTemp) {
    currentState = Green;
  } else if (temp < LowerTemp) {
    currentState = Blue;
  } else if (temp > HigherTemp) {
    currentState = Red;
  }

  switch (currentState) {
    case Green:
      digitalWrite(LED1_Red, LOW);
      digitalWrite(LED2_Blue, LOW);
      digitalWrite(LED3_Green, HIGH);
      delay (2000);
      break;

    case Blue:
      digitalWrite(LED1_Red, LOW);
      digitalWrite(LED2_Blue, HIGH);
      digitalWrite(LED3_Green, LOW);
      delay (2000);

      break;

    case Red:
      digitalWrite(LED1_Red, HIGH);
      digitalWrite(LED2_Blue, LOW);
      digitalWrite(LED3_Green, LOW);
      delay (2000);
      break;
    }
}