Amazon DRS Promise: Never Miss Coffee Break Again! https://www.hackster.io/coffee-drinkers/amazon-drs-promise-never-miss-coffee-break-again-a88584

coffeeAmazonDRS2.ino

/*******************************************************************
 Arduino Sketch to reorder items via Amazon Dash Service
 Written by @RonDagDag and Johnathan Hottell
 
 Read more at https://www.hackster.io/coffee-drinkers/amazon-drs-promise-never-miss-coffee-break-again-a88584
 Licensed under the Apache License, Version 2.0 (the "License");
 http://www.apache.org/licenses/LICENSE-2.0

 Unless required by applicable law or agreed to in writing, software
 distributed under the License is distributed on an "AS IS" BASIS,
 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 See the License for the specific language governing permissions and
 limitations under the License.
 *******************************************************************/
 
#ifdef ESP8266 
#include <ESP8266WiFi.h>
#include <WiFiClientSecure.h>
#else
#include <WiFi101.h>
#endif

#include "AmazonDRS.h"

AmazonDRS DRS = AmazonDRS();

//WiFi creds ----------------------------------------------------------------------------------
char ssid[] = ""; //  your network SSID (name)
char pass[] = "";    // your network password (use for WPA, or use as key for WEP)
//------------------------------------------------------------------------------------------------------

#define slotNumber 1 //This will vary for multi slot devices - dash buttons typically only serve one product/slot

static String slotStatus = "true"; //boolean which depicts if slot is available for replenishment
static String slotId = "e2d8d2a3-ecf3-7609-bc02-a1bbb776bdf8";     //unique slot id ex: 0a5038b7-7609-0a5038b7-7609-4b81-b87e-3e291f386324-b87e-3e291f386324
int status = WL_IDLE_STATUS;

//Distance sensor defs
int orderThreshold = 10;  //the distance threshold in cm to place an order
const int trigPin = 2;
const int echoPin = 4;
long duration, inches, cm, cmAverage;
int distanceArray[11];
int averagingCounter = 0;
int placeOrderTrigger = 0;
int orderPlaced = 0;


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

  pinMode (12, INPUT_PULLUP);  //Set up digital pin for reset button
  pinMode (13, OUTPUT);        //LED used for when an order is placed

   #ifdef ESP8266 
   WiFiClientSecure client;
   #else
   WiFiSSLClient client;
   #endif
   //Start up DRS
   DRS.begin(&client);

  //connect to WiFi
  Serial.println("Initializing DRS... connecting to WiFi");
  while (status != WL_CONNECTED) {
    // Connect to WPA/WPA2 network. Change this line if using open or WEP network:
    status = WiFi.begin(ssid, pass);
    Serial.println(".");
    delay(3000);
    status = WiFi.status();
  }

  Serial.print("Connected to ");
  Serial.println(WiFi.SSID());

  //initialize slots
  DRS.retrieveSubscriptionInfo();  //check slot statuses

  slotStatus = DRS.getSlotStatus(slotNumber);
  slotId = DRS.getSlotId(slotNumber);
}


////////////////////////////////////////////////////
void loop() {

  sensorPing();  //take a distance reading
  // increment counter for averaging
  if (averagingCounter >= 11) {  
    averagingCounter = 0;
  }   
  else{
    averagingCounter ++;
  } 
  
  //put the distance reading into the array
  distanceArray[averagingCounter] = cm; 
  //calculate the average
  cmAverage = ((distanceArray[0] + distanceArray[1] + distanceArray[2] + distanceArray[3] + distanceArray[4] + distanceArray[5] + distanceArray[6] + distanceArray[7] + distanceArray[8] + distanceArray[9] + distanceArray[10] + distanceArray[11])/12);

  Serial.print("Average cm: ");
  Serial.println(cmAverage);

  if (cmAverage >= orderThreshold and orderPlaced == 0)
   {
   //Check if slot is available, if so replenish
   if(slotStatus == "true")   //if the product in slot are available
   {
     //we have a match! replenish the products associated with that slot!
     orderPlaced = 1;
     digitalWrite(13, HIGH);
     Serial.println("Placing Order");
     DRS.requestReplenishmentForSlot(slotId);
   }
   else
   {
    // Serial.print("Sorry, slot ");
     //Serial.print(slotId);
     //Serial.println(" is not available at this time");
     orderPlaced = 1;                                       //comment these out later, for testing
     digitalWrite(13, HIGH);                                //comment these out later, for testing
     Serial.println("Placing Order");
     //Serial.println("Order not placed, locking out");       //comment these out later, for testing
   }
  }
  else if (digitalRead(12) == LOW)
   {
    orderPlaced = 0;
    digitalWrite(13, LOW);
    Serial.println("Reseting Order");
   }

  delay(2000);

  
}


////////////////////////////////////////////////////
void sensorPing()
{
  // The sensor is triggered by a HIGH pulse of 10 or more microseconds.
  // Give a short LOW pulse beforehand to ensure a clean HIGH pulse:
  pinMode(trigPin, OUTPUT);
  digitalWrite(trigPin, LOW);
  delayMicroseconds(2);
  digitalWrite(trigPin, HIGH);
  delayMicroseconds(10);
  digitalWrite(trigPin, LOW);

  pinMode(echoPin, INPUT);
  duration = pulseIn(echoPin, HIGH);

  cm = microsecondsToCentimeters(duration);   // convert the time into a distance
  Serial.print("cm: ");
  Serial.println(cm);

}

/////////////////////////////////////////////////
long microsecondsToInches(long microseconds)
{
  return microseconds / 74 / 2;
}

//////////////////////////////////////////////////
long microsecondsToCentimeters(long microseconds)
{
  return microseconds / 29 / 2;
}