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// ArduinoJson - arduinojson.org
// Copyright Benoit Blanchon 2014-2018
// MIT License
#pragma once
#include "../Configuration.hpp"
#include "../Polyfills/math.hpp"
#include "../TypeTraits/FloatTraits.hpp"
namespace ArduinoJson {
namespace Internals {
template <typename TFloat>
struct FloatParts {
uint32_t integral;
uint32_t decimal;
int16_t exponent;
int8_t decimalPlaces;
FloatParts(TFloat value) {
uint32_t maxDecimalPart = sizeof(TFloat) >= 8 ? 1000000000 : 1000000;
decimalPlaces = sizeof(TFloat) >= 8 ? 9 : 6;
exponent = normalize(value);
integral = uint32_t(value);
// reduce number of decimal places by the number of integral places
for (uint32_t tmp = integral; tmp >= 10; tmp /= 10) {
maxDecimalPart /= 10;
decimalPlaces--;
}
TFloat remainder = (value - TFloat(integral)) * TFloat(maxDecimalPart);
decimal = uint32_t(remainder);
remainder = remainder - TFloat(decimal);
// rounding:
// increment by 1 if remainder >= 0.5
decimal += uint32_t(remainder * 2);
if (decimal >= maxDecimalPart) {
decimal = 0;
integral++;
if (exponent && integral >= 10) {
exponent++;
integral = 1;
}
}
// remove trailing zeros
while (decimal % 10 == 0 && decimalPlaces > 0) {
decimal /= 10;
decimalPlaces--;
}
}
static int16_t normalize(TFloat& value) {
typedef FloatTraits<TFloat> traits;
int16_t powersOf10 = 0;
int8_t index = sizeof(TFloat) == 8 ? 8 : 5;
int bit = 1 << index;
if (value >= ARDUINOJSON_POSITIVE_EXPONENTIATION_THRESHOLD) {
for (; index >= 0; index--) {
if (value >= traits::positiveBinaryPowerOfTen(index)) {
value *= traits::negativeBinaryPowerOfTen(index);
powersOf10 = int16_t(powersOf10 + bit);
}
bit >>= 1;
}
}
if (value > 0 && value <= ARDUINOJSON_NEGATIVE_EXPONENTIATION_THRESHOLD) {
for (; index >= 0; index--) {
if (value < traits::negativeBinaryPowerOfTenPlusOne(index)) {
value *= traits::positiveBinaryPowerOfTen(index);
powersOf10 = int16_t(powersOf10 - bit);
}
bit >>= 1;
}
}
return powersOf10;
}
};
}
}
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