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

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

const int voltpin = A0;
const int PCrelay = 2;
const int fanrelay = 3;
const int temppin = A1;
float voltmeasure;
float tempmeasure; 
bool sleep;

// create an OLED display object connected to I2C
Adafruit_SSD1306 display(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

void setup() {
  Serial.begin(9600);

  // initialize OLED display with I2C address 0x3C
  if (!display.begin(SSD1306_SWITCHCAPVCC, 0x3C)) {
    Serial.println(F("failed to start SSD1306 OLED"));
    while (1);
  }

  delay(500);         // wait two seconds for initializing
  display.clearDisplay(); // clear display

  display.setTextSize(2);         // set text size
  display.setTextColor(WHITE); // set text color
  display.setCursor(0, 2);       // set position to display (x,y)
  display.println("Battery");
  display.println("Status");
  display.setTextSize(1); 
  display.println("Initialising....");
  display.display();
}
void loop() {
  delay(1000);
  
  tempmeasure = analogRead(temppin);
  voltmeasure = analogRead(voltpin)*5.00/1023*5.00;
  if (tempmeasure >500) {
    digitalWrite(fanrelay, HIGH);
    }
    else digitalWrite(temppin, LOW);
  if (voltmeasure >21 ) {
    sleep = true; 
    }
  if  (voltmeasure <21 && sleep) {
    while (sleep)
    sleep = false;
    digitalWrite(PCrelay, HIGH);
    }
    else  digitalWrite(PCrelay, LOW);

    Serial.print("Volt \ttemperature \n");
Serial.print(voltmeasure);
Serial.print("\t");
Serial.print(tempmeasure);
Serial.print("\t");
Serial.println(sleep);

display.clearDisplay();

  // display Voltage
  display.setTextSize(1);
  display.setCursor(0,2);
  display.print("Voltage: ");
  display.setTextSize(2);
  display.setCursor(0,15);
  display.print(voltmeasure);
  display.print(" ");
  display.setTextSize(1);
   display.write(167);
  display.setTextSize(2);
  display.print("V");
// Display Temperature
   display.setTextSize(1);
  display.setCursor(0, 35);
  display.print("Temperature: ");
  display.setTextSize(2);
  display.setCursor(0, 45);
  display.print(tempmeasure);
  display.print(" C"); 

display.display();



}