/*
 * This code (shamelessly copied from Arduino and modified for micro:bit) will print doubles to the uBit.serial
 *  
 * Print.cpp - Base class that provides print() and println()
 * Copyright (c) 2008 David A. Mellis. All right reserved.
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 * 
 * Modifications by Matthew Ford, Copyright(c) 2015 Forward Computing and Control Pty. Ltd.
 */

#include "MicroBit.h"
MicroBit uBit;

size_t printFloat(double number, uint8_t digits);

int main() {
    uBit.init();
    uBit.display.print("Start"); // wait a bit so you can open terminal

    uBit.serial.printf("test of printf d format %d\n",(int)10);
    printFloat(0.0010,5);
    uBit.serial.printf("\n");
    //uBit.serial.printf("test of printf e format %e\n",(double)10.0);  These do NOT work DO NOT use
    //uBit.serial.printf("test of printf f format %f\n",(double)10.0);  These do NOT work DO NOT use
    release_fiber(); // finished with setup, release the fibers!!
}

size_t printFloat(double number, uint8_t digits) { 
  size_t n = 0;
  
  if (isnan(number)) return uBit.serial.printf("nan");
  if (isinf(number)) return uBit.serial.printf("inf");
  if (number > 4294967040.0) return uBit.serial.printf("ovf");  // constant determined empirically
  if (number <-4294967040.0) return uBit.serial.printf("ovf");  // constant determined empirically
  
  // Handle negative numbers
  if (number < 0.0)
  {
     n += uBit.serial.printf("-");
     number = -number;
  }

  // Round correctly so that print(1.999, 2) prints as "2.00"
  double rounding = 0.5;
  for (uint8_t i=0; i<digits; ++i)
    rounding /= 10.0;
  
  number += rounding;

  // Extract the integer part of the number and print it
  unsigned long int_part = (unsigned long)number;
  double remainder = number - (double)int_part;
  n += uBit.serial.printf("%lu",int_part);

  // Print the decimal point, but only if there are digits beyond
  if (digits > 0) {
    n += uBit.serial.printf("."); 
  }

  // Extract digits from the remainder one at a time
  while (digits-- > 0)
  {
    remainder *= 10.0;
    int toPrint = int(remainder);
    n += uBit.serial.printf("%d",toPrint);
    remainder -= toPrint; 
  } 
  
  return n;
}