//DHT22 library "DHT sensor library"
#include "DHT.h"
#define DHTPIN 2 // what pin we’re connected to
#define DHTTYPE DHT22 // DHT 22 (AM2302)
DHT dht(DHTPIN, DHTTYPE, 6);

//OLED library "Adafruit SSD1306"
#include <SPI.h>
#include <Wire.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels

// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
#define OLED_RESET     4 // Reset pin # (or -1 if sharing Arduino reset pin)
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, OLED_RESET);


void setup() 
{
  Serial.begin(9600);
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) 
  { // สั่งให้จอ OLED เริ่มทำงานที่ Address 0x3C
    Serial.println("SSD1306 allocation failed");
  } 
  else 
  {
    Serial.println("ArdinoAll OLED Start Work !!!");
  }

  Serial.println("DHTxx test!");

  dht.begin();
}

void loop() 
{
  // Wait a few seconds between measurements.
  delay(2000);

  // Reading temperature or humidity takes about 250 milliseconds!
  // Sensor readings may also be up to 2 seconds ‘old’ (its a very slow sensor)
  float h = dht.readHumidity();         // Read Humidity
  float t = dht.readTemperature();      // Read temperature as Celsius
  float f = dht.readTemperature(true);  // Read temperature as Fahrenheit

  // Check if any reads failed and exit early (to try again).
  if (isnan(h) || isnan(t) || isnan(f)) 
  {
    Serial.println("Failed to read from DHT sensor!");
    return;
  }

  // Compute heat index
  // Must send in temp in Fahrenheit!
  float hi = dht.computeHeatIndex(f, h);

  //Print reading value on screen
  Serial.print("Humidity: ");
  Serial.print(h);
  Serial.print(" %\t");
  Serial.print("Temperature: ");
  Serial.print(t);
  Serial.println(" *C ");

  //Send reading value to OLED
  //OLED initialize
  display.clearDisplay(); // ลบภาพในหน้าจอทั้งหมด
  display.setTextColor(WHITE, BLACK);  //กำหนดข้อความสีขาว ฉากหลังสีดำ
  
  //display humidity
  display.setCursor(0, 10); // กำหนดตำแหน่ง x,y ที่จะแสดงผล
  display.setTextSize(2); // กำหนดขนาดตัวอักษร
  display.print("H: "); // แสดงผลข้อความ

  display.setCursor(35, 10);
  display.setTextSize(2);
  display.println(h,2);

  display.setCursor(110, 10);
  display.setTextSize(2);
  display.println("%");

  //display temperature
  display.setCursor(0, 40);
  display.setTextSize(2);
  display.println("T: ");
  
  display.setCursor(35, 40);
  display.setTextSize(2);
  display.println(t, 2);

  display.setCursor(110, 40);
  display.setTextSize(2);
  display.println("C");

  display.display(); // สั่งให้จอแสดงผล
  
}