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

// WiFi credentials for Wokwi
char ssid[] = "Wokwi-GUEST";
char pass[] = "";
String UID = "U71463b22a98d92c20fd04052510e6e89";

// Google Form endpoint
const String FORM_ENDPOINT = "https://docs.google.com/forms/d/e/"
                             "1FAIpQLSdfGlCv0nPVg1fvyQi177cgja9mgNdhMRqnH9Bm8hVGUwWvhA/"
                             "formResponse?usp=pp_url&"
                             "entry.683095985={UID}&"
                             "entry.1513483625={distance}&"
                             "entry.1153056995={water_level}&"
                             "submit=Submit";

WiFiClient client;

unsigned long myChannelNumber = 2254066;
const char * myWriteAPIKey = "DTV09I0TYO6QGNGZ";
int statusCode;

// Setup the sensor pins
const int trigPin = 26;  // Trigger pin
const int echoPin = 27;  // Echo pin

void setup() {
  // Start Serial Monitor
  Serial.begin(115200);
  
  // WiFi setup
  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, pass);

  // Wait until connected to Wi-Fi
  Serial.print("Connecting to WiFi...");
  while (WiFi.status() != WL_CONNECTED) {
    delay(500);
    Serial.print(".");
  }
  Serial.println("\nConnected to WiFi!");
  
  // Setup sensor pins
  pinMode(trigPin, OUTPUT);  // Trigger pin
  pinMode(echoPin, INPUT);   // Echo pin
}

long getDistance() {
  // Send a pulse to trigger the sensor
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  
  // Measure the duration of the pulse on the Echo pin
  long duration = pulseIn(echoPin, HIGH);
  
  // Calculate distance in cm (speed of sound is 0.034 cm/us)
  long distance = (duration * 0.034) / 2;
  return distance;
}

void loop() {
  // Get the measured distance from the sensor
  long distance = getDistance();
  
  // Simulate the water level (random between 0 and 20 cm)
  float simulated_water_level = 15; // Simulated water level between 0 and 20 cm
  
  // Calculate the distance between the sensor and water surface
  float water_distance = 25 - simulated_water_level; // The distance is the height of the pipe minus the water level
  
  // Prepare the URL with formatted parameters
  String url = FORM_ENDPOINT;
  url.replace("{UID}", UID);
  url.replace("{distance}", String(water_distance));
  url.replace("{water_level}", String(simulated_water_level));

  // Send data to Google Form using HTTP GET request
  if (WiFi.status() == WL_CONNECTED) {
    HTTPClient http;
    http.begin(url);  // Specify the URL
    int httpResponseCode = http.GET();  // Send GET request

    // Print response
    if (httpResponseCode == 200) {
      Serial.println("Data sent successfully!");
    } else {
      Serial.print("Error sending data. HTTP code: ");
      Serial.println(httpResponseCode);
    }
    http.end();  // Free resources
  }

  // Toggle LED to indicate action
  digitalWrite(32, HIGH);
  delay(1000);
  digitalWrite(32, LOW);

  // Delay for 10 seconds
  delay(10000);
}