#include <WiFi.h>
#include <HTTPClient.h>
#include <ArduinoJson.h>

// WiFi credentials
const char* ssid = "Wokwi-GUEST";
const char* password = "";

// Google Script deployment URL
const char* googleScriptURL = "https://script.google.com/macros/s/AKfycbzShXXqf3RYHLsb4NM2NHX2cSkD1JOYYzTa9LhxWsGA-Ob9SgMRWVqY9ViNhbu5bh0H/exec";

// Sensor pins
const int trigPin = 5;
const int echoPin = 18;
const int buzzerPin = 15;

// Variables
long duration;
float distance;

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

  // Initialize pins
  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);
  pinMode(buzzerPin, OUTPUT);

  // Initialize Wi-Fi
  WiFi.mode(WIFI_STA);
  WiFi.begin("Wokwi-GUEST", "");

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

void loop() {
  // Read distance from ultrasonic sensor
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  duration = pulseIn(echoPin, HIGH);
  distance = (duration * 0.034) / 2;
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");

  // Trigger buzzer if distance is below threshold
  if (distance < 10.0) {
    digitalWrite(buzzerPin, HIGH);
  } else {
    digitalWrite(buzzerPin, LOW);
  }

  // Prepare data to send to Google Sheets
  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;
    http.begin(googleScriptURL);
    http.addHeader("Content-Type", "application/json");

    // Create JSON payload
    StaticJsonDocument<200> doc;
    doc["distance"] = distance;

    String json;
    serializeJson(doc, json);

    int httpResponseCode = http.POST(json);

    if (httpResponseCode > 0) {
      String response = http.getString();
      Serial.println(httpResponseCode);
      Serial.println(response);
    } else {
      Serial.print("Error on sending POST: ");
      Serial.println(httpResponseCode);
    }

    http.end();
  } else {
    Serial.println("WiFi not connected");
  }

  delay(5000); // Delay 5 seconds before next read
}