// Mostra alternativamente Temperatura e Umidità

#include <dht.h>
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 32 // OLED display height, in pixels
//#define SCREEN_HEIGHT 64

#define DHT_PIN A0

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

dht DHT;
float getTemperature() {
  return DHT.temperature;
}
float getHumidity() {
  return DHT.humidity;
}

bool displayT=true;

void setup() {
  pinMode(DHT_PIN, INPUT);

  if(!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) { 
    Serial.println(F("SSD1306 allocation failed"));
    for(;;); // Don't proceed, loop forever
  }
  // Show initial display buffer contents on the screen --
  // the library initializes this with an Adafruit splash screen.
  display.display();
  // Clear the buffer
  display.clearDisplay();  
}

void loop() {
  static long startTime = 0;
  long currentTime;
 
  DHT.read22(DHT_PIN);
 
  // Get current time
  currentTime = millis();
 
  // Checks 1 second passed
  if ((currentTime - startTime) > 3000) {
    startTime = currentTime;
    // Update temperature
    float temperature = getTemperature();
    int v=temperature;
    // Normalizzo temperatura
    if (v<15) {
      v=15;
    }
    if (v>35) {
      v=35;
    }
    v = map (v, 15, 35, 0, 102);
    display.clearDisplay();
    display.setTextSize(1);             
    display.setCursor(0,2);         
    display.print("15");
    
    display.setCursor(115,2);             // Start at top-left corner
    display.print("35");
    display.drawRect(0, 0, 128, 11, INVERSE);
    display.fillRect(13, 2, v, 7, INVERSE);
    display.setTextColor(WHITE);        // Draw white text
    
    if (displayT) {
       display.setTextSize(2);
       display.setCursor(5,16);          
        display.print("Temp ");
        display.print(temperature, 1);
        display.print("C");
    } else {
        // Update humidity
        float humidity = getHumidity();
        display.setTextSize(2);
        display.setCursor(20,16);          
        display.print("Hum ");
        display.print(humidity, 0);
        display.print("%");
    }
    
    displayT=!displayT;
    display.display();
  }
}