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

#define OLED_SDA 21
#define OLED_SCL 19
#define OLED_RESET -1  // Reset pin not used in this example

Adafruit_SSD1306 display(128, 64, &Wire, OLED_RESET); // Create display object

#define ECHO_PIN1 15
#define TRIG_PIN1 2

#define ECHO_PIN2 5
#define TRIG_PIN2 18

#define ECHO_PIN3 26
#define TRIG_PIN3 27

int LEDPIN1 = 13;
int LEDPIN2 = 12;
int LEDPIN3 = 14;

void setup() {
  Serial.begin(115200);

  if (!display.begin(0x3C, OLED_SDA, OLED_SCL)) 
 {

    Serial.println(F("SSD1306 allocation failed"));
    for (;;);
  }

  display.display(); // Show initialization message

  delay(2000);  // Pause for 2 seconds

  display.clearDisplay();
  display.display();

  pinMode(LEDPIN1, OUTPUT);
  pinMode(TRIG_PIN1, OUTPUT);
  pinMode(ECHO_PIN1, INPUT);

  pinMode(LEDPIN2, OUTPUT);
  pinMode(TRIG_PIN2, OUTPUT);
  pinMode(ECHO_PIN2, INPUT);

  pinMode(LEDPIN3, OUTPUT);
  pinMode(TRIG_PIN3, OUTPUT);
  pinMode(ECHO_PIN3, INPUT);
}

float readDistance1CM() {
  digitalWrite(TRIG_PIN1, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN1, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN1, LOW);
  int duration = pulseIn(ECHO_PIN1, HIGH);
  display.setCursor(0, 20);
  display.print("Parking Spot 1: ");
  display.println(duration * 0.034 / 2 < 200 ? "Free" : "Occupied");
  display.display();
  return duration * 0.034 / 2;
}

float readDistance2CM() {
  digitalWrite(TRIG_PIN2, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN2, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN2, LOW);
  int duration = pulseIn(ECHO_PIN2, HIGH);
  display.setCursor(0, 30);
  display.print("Parking Spot 2: ");
  display.println(duration * 0.034 / 2 < 200 ? "Free" : "Occupied");
  display.display();
  return duration * 0.034 / 2;
}

float readDistance3CM() {
  digitalWrite(TRIG_PIN3, LOW);
  delayMicroseconds(2);
  digitalWrite(TRIG_PIN3, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN3, LOW);
  int duration = pulseIn(ECHO_PIN3, HIGH);
  display.setCursor(0, 40);
  display.print("Parking Spot 3: ");
  display.println(duration * 0.034 / 2 < 200 ? "Free" : "Occupied");
  display.display();
  return duration * 0.034 / 2;
}

void loop() {
  float distance1 = readDistance1CM();
  float distance2 = readDistance2CM();
  float distance3 = readDistance3CM();

  // Check the status of parking spots and display the information
  bool isOccupied1 = distance1 < 200;
  bool isOccupied2 = distance2 < 200;
  bool isOccupied3 = distance3 < 200;

  digitalWrite(LEDPIN1, isOccupied1 ? HIGH : LOW);
  digitalWrite(LEDPIN2, isOccupied2 ? HIGH : LOW);
  digitalWrite(LEDPIN3, isOccupied3 ? HIGH : LOW);

  // Display the status of each parking spot on the OLED screen
  display.clearDisplay();
  display.setCursor(0, 0);
  display.setTextSize(1);
  display.setTextColor(SSD1306_WHITE);
  display.print("Parking Spot 1: ");
  display.println(isOccupied1 ? "Occupied" : "Free");
  display.print("Parking Spot 2: ");
  display.println(isOccupied2 ? "Occupied" : "Free");
  display.print("Parking Spot 3: ");
  display.println(isOccupied3 ? "Occupied" : "Free");
  display.display();

  // You can add additional logic here to trigger alerts or notifications as needed.

  delay(1000); // Adjust the delay interval as needed.
}