#include <WiFi.h>
#include <PubSubClient.h>
void callback(char* subscribetopic, byte* payload, unsigned int payloadLength);

#define ORG "ltibku";
#include "ultrasonic.h"
#define DEVICE_TYPE"ESP32_controller"
#define DEVICE_ID"Assignment_4"
#define TOKEN"&S?LQdLRzh3n2gkyDt"

char server[]=ORG".meassaging.internertofthings.ibmcloud.com";
char publishTopic1[]="iot-2/evt/status1/fmt/json";
char subscribetpic[] ="iot-2/cmd/test/fmt/String";
char authMethod[]="use-token-auth";
char token[] = TOKEN;
char clientId[] = "d:" ORG ":" DEVICE_TYPE ":" DEVICE_ID;
long now;

WiFiClient wificlient;
PubSubClient client(server, 1883, callback, wificlient);

#define echoPin 12 // attach pin D2 Arduino to pin Echo of HC-SR04
#define trigPin 13 //attach pin D3 Arduino to pin Trig of HC-SR04

// defines variables
long duration; // variable for the duration of sound wave travel
int distance; // variable for the distance measurement

void setup() {
    ultrasonic.begin();
  pinMode(trigPin, OUTPUT); // Sets the trigPin as an OUTPUT
  pinMode(echoPin, INPUT); // Sets the echoPin as an INPUT
  Serial.begin(9600); // // Serial Communication is starting with 9600 of baudrate speed
  Serial.println("Ultrasonic Sensor HC-SR04 Test"); // print some text in Serial Monitor
  Serial.println("with Arduino UNO R3");
  wificonnect();
  mqttconnect();
}
void loop() {
  // Clears the trigPin condition
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  // Sets the trigPin HIGH (ACTIVE) 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);
  // Calculating the distance
  distance = duration * 0.034 / 2; // Speed of sound wave divided by 2 (go and back)
  // Displays the distance on the Serial Monitor
  Serial.print("Distance: ");
  Serial.print(distance);
  Serial.println(" cm");
  delay(500);
  publishData(distance );
  delay(1000);
  if(!client.loop())
  {
      mqttconnect();
  }
void PublishData(int distance)
{
    mqttconnect();
   String payload ="{\"d\":{\"distance\":";
    payload += distance;
    payload += "," "\"Distance\":";
   payload += "}}";
    
    Serial.print("sending payload: ");
    Seerial.println(payload);
    if (client.publish(publishTopic, (char*) payload.c_str()))
    {
        Serial.println("publish ok");
    }
else{
     Serial.println("publish failed");

}
}
void mqttconnect(){
    if(!client.connected()){
       Serial.println("Reconnecting client to");
        Serial.println(server);
        while (!!!client.connect(clientId, authMethod,token)){
             Serial.print(".");
             delay(500);        }  
    }
    initManagedDevice();
     Serial.println();
}
}
void wificonnect()
{
     Serial.println();
     Serial.print("connecting to");
      Serial.println("Wokwi-GUEST","",6);
      while (WiFi.status() != WL_CONNECTED){
          delay(500);
           Serial.println(".");
      }
       Serial.println("");
        Serial.println("wifi connected");
         Serial.println("IP address:");
          Serial.println(WiFi.localIP());

}
void  initManagedDevice(){
    if(client.subscribe(subscribetopic)){
     Serial.println("subscribe to cmd ok");   
    }
    else{
        Serial.println("subscribe to cmd failed");
    }
}