#include <WiFi.h>
#include "ThingSpeak.h"
#define SOUND_SPEED 0.034
#define CM_TO_INCH 0.393701

const char* WIFI_NAME = "Wokwi-GUEST";
const char* WIFI_PASSWORRD ="";
const int myChannelNumber =2316429 ;
const char* myApiKey = "5N2SPHOB5AEX1IKU";
const char* server = "api.thingspeak.com";
const int trigPin = 5;
const int echoPin = 18;

//define sound speed in cm/uS


long duration;
float distanceCm;
float distanceInch;
WiFiClient client;

void setup() {
  Serial.begin(115200); // Starts the serial communication
  pinMode(trigPin, OUTPUT); // Sets the trigPin as an Output
  pinMode(echoPin, INPUT); // Sets the echoPin as an Input
  WiFi.begin(WIFI_NAME, WIFI_PASSWORRD);
  while (WiFi.status() != WL_CONNECTED){
    delay(100);
    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
  ThingSpeak.setField(5,distanceCm);
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  // Sets the trigPin on HIGH state for 10 micro seconds
  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
  distanceCm = duration * SOUND_SPEED/2;
  
  // Convert to inches
  distanceInch = distanceCm * CM_TO_INCH;
  
  // Prints the distance in the Serial Monitor
  Serial.print("Distance (cm): ");
  Serial.println(distanceCm);
  Serial.print("Distance (inch): ");
  Serial.println(distanceInch);
  
  int x = ThingSpeak.writeFields(myChannelNumber,myApiKey);
  
  delay(1000);
}