// Copyright Epic Games, Inc. All Rights Reserved.

#pragma once

#include "CoreMinimal.h"
#include "Containers/UnrealString.h"

/*
double is a 64 bit IEEE 754 double precision Floating Point Number
1 bit for the sign, 11 bits for the exponent, and 52* bits for the value
15.5 decimal digits of precision (max value*: ‭4`503`599`627`370`495)
|------------------------------------------------------------------------------
| 900`000.000`000`001     --> up to 10 days   with    1 ns precision
|  90`000.000`000`000`1   --> up to 25 hours  with  0.1 ns precision (100 ps)
|   9`000.000`000`000`01  --> up to 2.5 hours with 0.01 ns precision (10 ps)
|     900.000`000`000`001 --> up to 15 min    with    1 ps precision
|------------------------------------------------------------------------------
|   3`600.000`000`000`001 --> 1 ps precision at 1 hour : NOT OK (16 digits)!!!
|  86`400.000`000`000`001 --> 1 ps precision at 1 day  : NOT OK (17 digits)!!!
|------------------------------------------------------------------------------
*/

namespace TimeUtils
{
static constexpr double Picosecond  = 0.000000000001;
static constexpr double Nanosecond  = 0.000000001;
static constexpr double Microsecond = 0.000001;
static constexpr double Milisecond  = 0.001;
static constexpr double Second      = 1.0;
static constexpr double Minute      = 60.0;
static constexpr double Hour        = 3600.0;
static constexpr double Day         = 86400.0;
static constexpr double Week        = 604800.0;

struct TRACEINSIGHTS_API FTimeSplit
{
    union
    {
        int32 Units[8];  // Units[0] = Days, Units[1] = Hours, ..., Units[7] = Picoseconds
        struct
        {
            int32 Days;
            int32 Hours;
            int32 Minutes;
            int32 Seconds;
            int32 Miliseconds;
            int32 Microseconds;
            int32 Nanoseconds;
            int32 Picoseconds;
        };
    };
    bool bIsZero;
    bool bIsNegative;
    bool bIsInfinite;
    bool bIsNaN;
};

TRACEINSIGHTS_API FString FormatTimeValue(const double Duration, const int32 NumDigits = 1);
TRACEINSIGHTS_API FString FormatTimeAuto(const double Duration, const int32 NumDigits = 1);
TRACEINSIGHTS_API FString FormatTimeMs(const double Duration, const int32 NumDigits = 2, bool bAddTimeUnit = false);
TRACEINSIGHTS_API FString FormatTime(const double Time, const double Precision = 0.0);
TRACEINSIGHTS_API FString FormatTimeHMS(const double Time, const double Precision = 0.0);
TRACEINSIGHTS_API void SplitTime(const double Time, FTimeSplit& OutTimeSplit);
TRACEINSIGHTS_API FString FormatTimeSplit(const FTimeSplit& TimeSplit, const double Precision = 0.0);
TRACEINSIGHTS_API FString FormatTimeSplit(const double Time, const double Precision = 0.0);

void TestTimeFormatting();
void TestTimeAutoFormatting();
void TestOptimizationIssue();
}  // namespace TimeUtils