Unicorn Finder (Kid Tracker for Techie Parents)

// ADAFRUIT NEOPIXEL GLOBALS ------------------------------------------
#include <Adafruit_NeoPixel.h>
#define PIN 6
Adafruit_NeoPixel strip = Adafruit_NeoPixel(8, PIN, NEO_GRB + NEO_KHZ800);

// ADAFRUIT ULTIMATE GPS GLOBALS -------------------------------------
#include <Adafruit_GPS_Alt.h>
#include <AltSoftSerial.h>
AltSoftSerial mySerial(8, 7);
Adafruit_GPS_Alt GPS(&mySerial);
#define GPSECHO false
boolean usingInterrupt = false;
void useInterrupt(boolean);
uint32_t timer = millis();
String lastCoor = "\"coords\": [0,0]";

// ARDUINO GSM GLOBALS ------------------------------------------------
#include <GSM.h>
#define PINNUMBER ""
#define GPRS_APN "hologram"
#define GPRS_LOGIN ""
#define GPRS_PASSWORD ""
GSMClient client;
GPRS gprs;
GSM gsmAccess; // pass (true) for debugger

// HOLOGRAM CLOUD GLOBALS ---------------------------------------------
char server[] = "23.253.146.203"; // the base URL or IP
int port = 9999; // 80 for HTTP, 443 for HTTPS, 999 for TCP
const char HOLOGRAMID[] = "xxxx"; //replace with 4 digit shared id from device details on dashboard
const char HOLOGRAMKEY[] = "xxxx"; //replace with 4 digit shared key from device details on dashboard

void setup() {
  Serial.begin(115200);
  
  // ADAFRUIT NEOPIXEL SETUP ------------------------------------------  
  Serial.println(F("Initializing Adafruit NeoPixels..."));
  strip.begin();
  strip.setBrightness(100); //adjust brightness here
  strip.show(); // Initialize all pixels to 'off'

  // ADAFRUIT GPS SETUP -----------------------------------------------
  Serial.println(F("Initializing Adafruit GPS..."));
  GPS.begin(9600);
  // Setup GPS to report the data we need
  GPS.sendCommand(PMTK_SET_NMEA_OUTPUT_RMCGGA);
  GPS.sendCommand(PMTK_SET_NMEA_UPDATE_1HZ);
  GPS.sendCommand(PGCMD_ANTENNA);
  useInterrupt(true);
  delay(1000);
  mySerial.println(F(PMTK_Q_RELEASE));

  // ARDUINO GSM SETUP ------------------------------------------------
  Serial.println(F("Initializing Arduino GSM..."));
  boolean notConnected = true;
  while(notConnected){
    if((gsmAccess.begin(PINNUMBER)==GSM_READY) & (gprs.attachGPRS(GPRS_APN, GPRS_LOGIN, GPRS_PASSWORD)==GPRS_READY)) {
      notConnected = false;
      Serial.println(F("Cellular Network Connected"));
    } else {
      Serial.println(F("Not Connected to Cellular Network"));
      delay(1000);
    }
  }

  Serial.print(F("Arduino UNO Free RAM: ")); Serial.println(freeRam());
  delay(1000);
}

 
void loop() {
  // ADAFRUIT NEOPIXEL LOOP ------------------------------------------ 
  Serial.println(F("Rainbow Cycling...")); 
  rainbowCycle(10);

  // ADAFRUIT GPS LOOP -----------------------------------------------
  if (GPS.newNMEAreceived()) {
    if (!GPS.parse(GPS.lastNMEA()))
      return;
  }
  
  String message;
  String newCoor = lastCoor;
  Serial.print(F("GPS Fixed: ")); Serial.println((int)GPS.fix);
  Serial.print(F("GPS Satellites: ")); Serial.println((int)GPS.satellites);
  if (GPS.fix + GPS.satellites > 1) {
    newCoor = "";
    newCoor.concat(F("\"gps\":"));
    newCoor.concat(GPS.latitude);
    newCoor.concat(F(", "));
    newCoor.concat(GPS.longitude);
    
    message.concat(F("{"));
    message.concat(newCoor);
    message.concat(F("}")); 

    Serial.print(F("Arduino UNO Free RAM: ")); Serial.println(freeRam());
  }

  // ARDUINO GSM / HOLOGRAM CLOUD LOOP -------------------------------
  Serial.print(F("Last Coordinates: ")); Serial.println(lastCoor);
  Serial.print(F("New Coordinates: ")); Serial.println(newCoor);
  if (lastCoor != newCoor) {
    char msgbuf[38];
    Serial.print(F("message: ")); Serial.println(message);
    message.toCharArray(msgbuf, 38);
    modemCloudWrite(msgbuf);
    lastCoor = newCoor;
  }

  Serial.println(F("Loop Finished"));
  Serial.println();
}


int freeRam () 
{
  extern int __heap_start, *__brkval; 
  int v; 
  return (int) &v - (__brkval == 0 ? (int) &__heap_start : (int) __brkval); 
}


// ADAFRUIT NEOPIXEL FUNTIONS ------------------------------------------
 
// Slightly different, this makes the rainbow equally distributed throughout
void rainbowCycle(uint8_t wait) {
  uint16_t i, j;
  for(j=0; j<256*10; j++) { // 10 cycles of all colors on wheel
    for(i=0; i< strip.numPixels(); i++) {
      strip.setPixelColor(i, Wheel(((i * 256 / strip.numPixels()) + j) & 255));
    }
    strip.show();
    delay(wait);
  }
}
 
// Input a value 0 to 255 to get a color value.
// The colours are a transition r - g - b - back to r.
uint32_t Wheel(byte WheelPos) {
  if(WheelPos < 85) {
   return strip.Color(WheelPos * 3, 255 - WheelPos * 3, 0);
  } else if(WheelPos < 170) {
   WheelPos -= 85;
   return strip.Color(255 - WheelPos * 3, 0, WheelPos * 3);
  } else {
   WheelPos -= 170;
   return strip.Color(0, WheelPos * 3, 255 - WheelPos * 3);
  }
}

// ARDUINO GSM / HOLOGRAM CLOUD FUNCTIONS -----------------------------

// Make a TCP write
bool modemCloudWrite(char * msg) {
  // if you get a connection send message then disconnect
  if (client.connect(server, port)) {
    Serial.println(F("Connected to Hologram"));
    client.beginWrite();
    client.print(F("A"));
    client.print((char*)HOLOGRAMID);
    client.print((char*)HOLOGRAMKEY);
    client.print(F(" "));
    client.print(F("S"));
    client.print(msg);
    client.println(F("\n\n"));
    client.endWrite();
  
    Serial.print(F("Message sent: "));
    Serial.println(msg);
    client.stop();
    Serial.println(F("Disconnecting Cellular"));
    Serial.println();
  }
}


// ADAFRUIT GPS FUNCTIONS -----------------------------
// Interrupt is called once a millisecond, looks for any new GPS data, and stores it
SIGNAL(TIMER0_COMPA_vect) {
  char c = GPS.read();
  // if you want to debug, this is a good time to do it!
#ifdef UDR0
  if (GPSECHO)
    if (c) UDR0 = c;  
    // writing direct to UDR0 is much much faster than Serial.print 
    // but only one character can be written at a time. 
#endif
}

void useInterrupt(boolean v) {
  if (v) {
    // Timer0 is already used for millis() - we'll just interrupt somewhere
    // in the middle and call the "Compare A" function above
    OCR0A = 0xAF;
    TIMSK0 |= _BV(OCIE0A);
    usingInterrupt = true;
  } else {
    // do not call the interrupt function COMPA anymore
    TIMSK0 &= ~_BV(OCIE0A);
    usingInterrupt = false;
  }
}