#include <WiFi.h>
#include "ThingSpeak.h"

const char* WIFI_NAME = "Wokwi-GUEST";
const char* WIFI_PASSWORD = "";  // Replace with your actual WiFi password
const int myChannelNumber = 2324330;
const char* myApiKey = "JKEPA4O0D6CEC55U";
const char* server = "api.thingspeak.com";

WiFiClient client;

const int trigPin = 5;
const int echoPin = 18;

// Define sound speed in cm/uS
#define SOUND_SPEED 0.034
#define CM_TO_INCH 0.393701

long duration;
float distanceCm;
float distanceInch;

void setup() {
  Serial.begin(9600); // Starts the serial communication
  pinMode(trigPin, OUTPUT); // Sets the trigPin as an Output
  pinMode(echoPin, INPUT); // Sets the echoPin as an Input

  // Connect to WiFi
  WiFi.begin(WIFI_NAME, WIFI_PASSWORD);
  while (WiFi.status() != WL_CONNECTED){
    delay(1000);
    Serial.println("WiFi not connected");
  }
  Serial.println("WiFi connected!");
  Serial.println("Local IP: " + String(WiFi.localIP()));
  WiFi.mode(WIFI_STA);
  ThingSpeak.begin(client);
}

void loop() {
  // Clears the trigPin
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  // Sets the trigPin on HIGH state for 10 microseconds
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);
  
  // Reads the echoPin, returns the sound wave travel time in microseconds
  duration = pulseIn(echoPin, HIGH);
  
  // Calculate the distance in centimeters
  distanceCm = duration * SOUND_SPEED / 2;
  
  // Send distance data to ThingSpeak
  ThingSpeak.setField(1, distanceCm);

  int x = ThingSpeak.writeFields(myChannelNumber, myApiKey);

  // Convert to inches
  distanceInch = distanceCm * CM_TO_INCH;
  
  // Print the distance in the Serial Monitor
  Serial.println("Distance (cm): " + String(distanceCm));

  // Check if data was sent to ThingSpeak successfully
  if(x == 200){
    Serial.println("Data pushed successfully");
  } else {
    Serial.println("Push error " + String(x));
  }
  Serial.println("---");

  delay(10000); // Delay for 10 seconds before the next measurement
}