#include <WiFi.h>
#include <U8g2lib.h>

#define SCREEN_WIDTH 128
#define SCREEN_HEIGHT 64
#define SCREEN_ADDRESS 0x3C

U8G2_SSD1306_128X64_NONAME_F_SW_I2C u8g2(U8G2_R0, /* clock=*/ 22, /* data=*/ 21, /* reset=*/ U8X8_PIN_NONE);

#define ECHO_PIN1 15 // Pins for Sensor 1
#define TRIG_PIN1 2  // Pins for Sensor 1

#define ECHO_PIN2 5   // Pins for Sensor 2
#define TRIG_PIN2 18  // Pins for Sensor 2

#define ECHO_PIN3 26  // Pins for Sensor 3
#define TRIG_PIN3 27  // Pins for Sensor 3

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

const char* ssid = "Wokwi-GUEST";
const char* password = "";
const char* apiKey = "WSJVHF5A15WWF3UQ";
const char* server = "api.thingspeak.com";

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

  u8g2.begin();

  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);

  connectToWiFi();
}

void connectToWiFi() {
  Serial.println("Connecting to WiFi");
  WiFi.begin(ssid, password);

  while (WiFi.status() != WL_CONNECTED) {
    delay(1000);
    Serial.println("Connecting to WiFi...");
  }

  Serial.println("Connected to WiFi");
}

float readDistance(int trigPin, int echoPin) {
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  int duration = pulseIn(echoPin, HIGH);
  return duration * 0.034 / 2;
}

void sendToThingSpeak(int field1, int field2, int field3) {
  WiFiClient client;
  if (client.connect(server, 80)) {
    String url = "/update?api_key=";
    url += apiKey;
    url += "&field1=";
    url += field1;
    url += "&field2=";
    url += field2;
    url += "&field3=";
    url += field3;

    Serial.println("Sending to ThingSpeak: " + url);

    client.print(String("GET ") + url + " HTTP/1.1\r\n" +
                 "Host: " + server + "\r\n" +
                 "Connection: close\r\n\r\n");
    delay(1000);

    Serial.println("Data sent to ThingSpeak");
  } else {
    Serial.println("Failed to connect to ThingSpeak");
  }

  client.stop();
}

void loop() {
  float distance1 = readDistance(TRIG_PIN1, ECHO_PIN1);
  float distance2 = readDistance(TRIG_PIN2, ECHO_PIN2);
  float distance3 = readDistance(TRIG_PIN3, ECHO_PIN3);

  bool isNearby1 = distance1 > 200;
  digitalWrite(LEDPIN1, isNearby1);

  bool isNearby2 = distance2 > 200;
  digitalWrite(LEDPIN2, isNearby2);

  bool isNearby3 = distance3 > 200;
  digitalWrite(LEDPIN3, isNearby3);

  sendToThingSpeak(isNearby1, isNearby2, isNearby3);

  Serial.print("Parking 1: ");
  Serial.println(isNearby1 ? "Available" : "Occupied");

  Serial.print("Parking 2: ");
  Serial.println(isNearby2 ? "Available" : "Occupied");

  Serial.print("Parking 3: ");
  Serial.println(isNearby3 ? "Available" : "Occupied");

  u8g2.clearBuffer();
  u8g2.setFont(u8g2_font_ncenB08_tr);
  u8g2.drawStr(0, 20, "SMART PARKING");

  // Display parking status
  u8g2.setFont(u8g2_font_ncenB08_tr);
  u8g2.setCursor(0, 40);
  u8g2.print("Parking 1: ");
  u8g2.print(isNearby1 ? "Available" : "Occupied");

  u8g2.setCursor(0, 50);
  u8g2.print("Parking 2: ");
  u8g2.print(isNearby2 ? "Available" : "Occupied");

  u8g2.setCursor(0, 60);
  u8g2.print("Parking 3: ");
  u8g2.print(isNearby3 ? "Available" : "Occupied");

  u8g2.sendBuffer();

delay(1500);
}