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//Revolving Games by Michelle Ma
//Revolving Games by Michelle Ma

#include 
#include 
#include "RTClib.h"
#include "Adafruit_LEDBackpack.h"
#include "Adafruit_GFX.h"
#include 
#include 

Adafruit_7segment matrix1 = Adafruit_7segment();
Adafruit_7segment matrix2 = Adafruit_7segment();
Adafruit_ADXL345 accel = Adafruit_ADXL345(12345);

RTC_DS1307 RTC; // Real Time Clock

const int chipSelect = 10; //for data logging
const int distancePin = 0; //A0 for IR sensor

const int threshold = 100; //collect data when someone near
const float radius = 0.65; //radius of door in meters
const float pi = 3.1415926;

File logfile;

int highScore;

void setup() {
  Serial.begin(9600);
  SD.begin(chipSelect);
  createFile();
  accel.begin();
  matrix1.begin(0x70);
  matrix2.begin(0x71);
  
  if (!RTC.isrunning()) {
    RTC.adjust(DateTime(__DATE__, __TIME__));
  }
  
  accel.setRange(ADXL345_RANGE_16_G);
  
  highScore = 0;
}

void createFile() {
  char filename[] = "LOGGER00.CSV";
  for (uint8_t i=0; i<100; i++) {
    filename[6] = i/10 + '0';
    filename[7] = i%10 + '0';
    if (!SD.exists(filename)) {
      logfile = SD.open(filename, FILE_WRITE);
      break;
    }
  }
  
  if (!logfile) {
    Serial.print("Couldn't create file");
    Serial.println();
    while(true);
  }
  Serial.print("Logging to: ");
  Serial.println(filename);
  
  Wire.begin();
  
  if (!RTC.begin()) {
    Serial.println("RTC error");
  }
  logfile.println("TimeStamp,IR Distance,Accel (m/s^2),RPM");
}

void loop() {
  
  DateTime now = RTC.now();
  sensors_event_t event; 
  accel.getEvent(&event);
  
  float distance = analogRead(distancePin);
  float acceleration = event.acceleration.z;
  float rpm;
  
  if (distance > threshold) {
    rpm = computeRpm();
  } else {
    rpm = 0;
  }
  
  if (rpm > highScore) {
    highScore = rpm;
  }
  
  logData(now, distance, acceleration, rpm);
  serialData(now, distance, acceleration, rpm);
  writeMatrices(int(rpm), int(highScore));
  
  Serial.println("Saved...");
  logfile.flush();
}

float computeRpm() {
  float velocity = computeVelocity();
  float result = abs(60.0*velocity)/(2.0*pi*radius);
  return result;
}

float computeVelocity() {
  float acceleration;
  float sum = 0;
  int samples = 100;
  int dt = 10; //millis
  for (int i=0; i