#include <TinyGPS++.h>
#include <wiring_private.h>

static const uint32_t GPSBaud = 115200;

// The TinyGPS++ object
TinyGPSPlus gps;

// The serial connection to the GPS device - Left side Grove connector.
// Left side Grove connector shares pins with I2C1 of 40 pin connector.
static Uart Serial3(&sercom3, PIN_WIRE_SCL, PIN_WIRE_SDA, SERCOM_RX_PAD_1, UART_TX_PAD_0);

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

  Serial3.begin(GPSBaud);
  pinPeripheral(PIN_WIRE_SCL, PIO_SERCOM_ALT);
  pinPeripheral(PIN_WIRE_SCL, PIO_SERCOM_ALT);
}
 
void loop()
{
  // This sketch displays information every time a new sentence is correctly encoded.
  while (Serial3.available() > 0)
    if (gps.encode(Serial3.read()))
      displayInfo();
 
  if (millis() > 5000 && gps.charsProcessed() < 10)
  {
    Serial.println(F("No GPS detected: check wiring."));
    while(true);
  }
}

void displayInfo()
{
  Serial.print(F("Location: ")); 
  if (gps.location.isValid())
  {
    Serial.print(gps.location.lat(), 6);
    Serial.print(F(","));
    Serial.print(gps.location.lng(), 6);
  }
  else
  {
    Serial.print(F("INVALID"));
  }

  Serial.print(F("  Date/Time: "));
  if (gps.date.isValid())
  {
    Serial.print(gps.date.month());
    Serial.print(F("/"));
    Serial.print(gps.date.day());
    Serial.print(F("/"));
    Serial.print(gps.date.year());
  }
  else
  {
    Serial.print(F("INVALID"));
  }

  Serial.print(F(" "));
  if (gps.time.isValid())
  {
    if (gps.time.hour() < 10) Serial.print(F("0"));
    Serial.print(gps.time.hour());
    Serial.print(F(":"));
    if (gps.time.minute() < 10) Serial.print(F("0"));
    Serial.print(gps.time.minute());
    Serial.print(F(":"));
    if (gps.time.second() < 10) Serial.print(F("0"));
    Serial.print(gps.time.second());
    Serial.print(F("."));
    if (gps.time.centisecond() < 10) Serial.print(F("0"));
    Serial.print(gps.time.centisecond());
  }
  else
  {
    Serial.print(F("INVALID"));
  }

  Serial.println();
}

void SERCOM3_0_Handler()
{
  Serial3.IrqHandler();
}
void SERCOM3_1_Handler()
{
  Serial3.IrqHandler();
}
void SERCOM3_2_Handler()
{
  Serial3.IrqHandler();
}
void SERCOM3_3_Handler()
{
  Serial3.IrqHandler();
}