//SD
#include "SD.h"
#define SD_ChipSelectPin 10
#include "TMRpcm.h"
#include "SPI.h"

// constants (staan vast)
const int TRIG_PIN = 6; // Arduino pin connected to Ultrasonic Sensor's TRIG pin
const int ECHO_PIN = 7; // Arduino pin connected to Ultrasonic Sensor's ECHO pin
const int SPEAKER_PIN  = 9; // Arduino pin connected to speaker pin
const int DISTANCE_THRESHOLD = 50; // centimeters (de afstand waarop de afstandssensor geactiveerd wordt)

// variables (veranderen)
float duration_us, distance_cm;

TMRpcm tmrpcm; //arduino library voor het lezen van de SD  kaart

void setup()
{
tmrpcm.speakerPin=9;//pin waar de speaker aan geconnect is
Serial.begin(9600);
  //Sonar Sensor
  pinMode(TRIG_PIN, OUTPUT); // set arduino pin to output mode
  pinMode(ECHO_PIN, INPUT);  // set arduino pin to input mode
  pinMode(SPEAKER_PIN, OUTPUT);  // set arduino pin to output mode

if(!SD.begin(SD_ChipSelectPin))
{
  Serial.println("SD fail");
  return;
}

}

void loop() {
// generate 10-microsecond pulse to TRIG pin
  digitalWrite(TRIG_PIN, HIGH);
  delayMicroseconds(10);
  digitalWrite(TRIG_PIN, LOW);

  // measure duration of pulse from ECHO pin
  duration_us = pulseIn(ECHO_PIN, HIGH);
  // calculate the distance
  distance_cm = 0.017 * duration_us;

  if(distance_cm < DISTANCE_THRESHOLD){
    tmrpcm.setVolume(6);
    tmrpcm.play("Track01.wav"); //ALS de afstand tot de afstandssensor lager is dan de treshhold -> play audio
  }

  // print the value to Serial Monitor
  Serial.print("distance: ");
  Serial.print(distance_cm);
  Serial.println(" cm");

  delay(5000);
}