#include <ESP8266WiFi.h>
#include <FirebaseArduino.h>

// Set these to run example.
#define FIREBASE_HOST "realtime-distance-sensor.firebaseio.com"
#define FIREBASE_AUTH "O5IKDBWKoCCPDYGeqxmLhM3Hn5maQZ4Yj3puRSSF"

#define WIFI_SSID  "AndroidHotspot8432" //"o2-WLAN93" 
#define WIFI_PASSWORD "5ea71cf6ed4c"  //"9592132995009940" 

#define echoPin  D7 // Echo Pin
#define trigPin D6 // Trigger Pin
long duration, distance; // Duration used to calculate distance

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

  pinMode(trigPin, OUTPUT);
  pinMode(echoPin, INPUT);

  // connect to wifi.
  WiFi.begin(WIFI_SSID, WIFI_PASSWORD);
  Serial.print("connecting");
  while (WiFi.status() != WL_CONNECTED) {
    Serial.print(".");
    delay(500);
  }

  Serial.println();
  Serial.print("connected: ");
  Serial.println(WiFi.localIP());
  Firebase.begin(FIREBASE_HOST, FIREBASE_AUTH);
}

void loop() {
  
digitalWrite(trigPin, LOW);
delayMicroseconds(2);
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);
duration = pulseIn(echoPin, HIGH);
//Calculate the distance (in cm) based on the speed of sound.
float distance = duration*0.0343/2;
Serial.println(distance);
Serial.println ( " cm");
delay (200);

digitalWrite(echoPin, HIGH);

//send data to firebase
Firebase.setFloat("dist", distance);

  digitalWrite(echoPin, LOW);
  delay(1000);
}