// Copyright 2010 Google Inc. All Rights Reserved.

// Maintainer: mec@google.com (Michael Chastain)

//

// Convert strings to numbers or numbers to strings.

#pragma once

#include <stddef.h>

#include <time.h>

#include <stdint.h>

#include <functional>

using std::less;

#include <limits>

using std::numeric_limits;

#include <string>

using std::string;

#include <vector>

using std::vector;

#include "gutil/int128.h"

#include "gutil/integral_types.h"

// IWYU pragma: no_include <butil/macros.h>

#include "gutil/macros.h" // IWYU pragma: keep

#include "gutil/port.h"

#include "gutil/stringprintf.h"

// START DOXYGEN NumbersFunctions grouping

/* @defgroup NumbersFunctions

 * @{ */

// Convert a fingerprint to 16 hex digits.

string Uint64ToString(uint64 fp);

// Formats a uint128 as a 32-digit hex string.

string Uint128ToHexString(uint128 ui128);

// Convert strings to numeric values, with strict error checking.

// Leading and trailing spaces are allowed.

// Negative inputs are not allowed for unsigned ints (unlike strtoul).

// Numbers must be in base 10; see the _base variants below for other bases.

// Returns false on errors (including overflow/underflow).

bool safe_strto32(const char* str, int32* value);

bool safe_strto64(const char* str, int64* value);

bool safe_strtou32(const char* str, uint32* value);

bool safe_strtou64(const char* str, uint64* value);

// Convert strings to floating point values.

// Leading and trailing spaces are allowed.

// Values may be rounded on over- and underflow.

bool safe_strtof(const char* str, float* value);

bool safe_strtod(const char* str, double* value);

bool safe_strto32(const string& str, int32* value);

bool safe_strto64(const string& str, int64* value);

bool safe_strtou32(const string& str, uint32* value);

bool safe_strtou64(const string& str, uint64* value);

bool safe_strtof(const string& str, float* value);

bool safe_strtod(const string& str, double* value);

// Parses buffer_size many characters from startptr into value.

bool safe_strto32(const char* startptr, int buffer_size, int32* value);

bool safe_strto64(const char* startptr, int buffer_size, int64* value);

// Parses with a fixed base between 2 and 36. For base 16, leading "0x" is ok.

// If base is set to 0, its value is inferred from the beginning of str:

// "0x" means base 16, "0" means base 8, otherwise base 10 is used.

bool safe_strto32_base(const char* str, int32* value, int base);

bool safe_strto64_base(const char* str, int64* value, int base);

bool safe_strtou32_base(const char* str, uint32* value, int base);

bool safe_strtou64_base(const char* str, uint64* value, int base);

bool safe_strto32_base(const string& str, int32* value, int base);

bool safe_strto64_base(const string& str, int64* value, int base);

bool safe_strtou32_base(const string& str, uint32* value, int base);

bool safe_strtou64_base(const string& str, uint64* value, int base);

bool safe_strto32_base(const char* startptr, int buffer_size, int32* value, int base);

bool safe_strto64_base(const char* startptr, int buffer_size, int64* value, int base);

// u64tostr_base36()

//    The inverse of safe_strtou64_base, converts the number agument to

//    a string representation in base-36.

//    Conversion fails if buffer is too small to to hold the string and

//    terminating NUL.

//    Returns number of bytes written, not including terminating NUL.

//    Return value 0 indicates error.

size_t u64tostr_base36(uint64 number, size_t buf_size, char* buffer);

// Similar to atoi(s), except s could be like "16k", "32M", "2G", "4t".

uint64 atoi_kmgt(const char* s);

inline uint64 atoi_kmgt(const string& s) {

    return atoi_kmgt(s.c_str());

}

// ----------------------------------------------------------------------

// FastIntToBuffer()

// FastHexToBuffer()

// FastHex64ToBuffer()

// FastHex32ToBuffer()

// FastTimeToBuffer()

//    These are intended for speed.  FastIntToBuffer() assumes the

//    integer is non-negative.  FastHexToBuffer() puts output in

//    hex rather than decimal.  FastTimeToBuffer() puts the output

//    into RFC822 format.

//

//    FastHex64ToBuffer() puts a 64-bit unsigned value in hex-format,

//    padded to exactly 16 bytes (plus one byte for '\0')

//

//    FastHex32ToBuffer() puts a 32-bit unsigned value in hex-format,

//    padded to exactly 8 bytes (plus one byte for '\0')

//

//    All functions take the output buffer as an arg.  FastInt() uses

//    at most 22 bytes, FastTime() uses exactly 30 bytes.  They all

//    return a pointer to the beginning of the output, which for

//    FastHex() may not be the beginning of the input buffer.  (For

//    all others, we guarantee that it is.)

//

//    NOTE: In 64-bit land, sizeof(time_t) is 8, so it is possible

//    to pass to FastTimeToBuffer() a time whose year cannot be

//    represented in 4 digits. In this case, the output buffer

//    will contain the string "Invalid:<value>"

// ----------------------------------------------------------------------

// Previously documented minimums -- the buffers provided must be at least this

// long, though these numbers are subject to change:

//     Int32, UInt32:        12 bytes

//     Int64, UInt64, Hex:   22 bytes

//     Time:                 30 bytes

//     Hex32:                 9 bytes

//     Hex64:                17 bytes

// Use kFastToBufferSize rather than hardcoding constants.

static const int kFastToBufferSize = 32;

char* FastInt32ToBuffer(int32 i, char* buffer);

char* FastInt64ToBuffer(int64 i, char* buffer);

char* FastUInt32ToBuffer(uint32 i, char* buffer);

char* FastUInt64ToBuffer(uint64 i, char* buffer);

char* FastHexToBuffer(int i, char* buffer) MUST_USE_RESULT;

char* FastTimeToBuffer(time_t t, char* buffer);

char* FastHex64ToBuffer(uint64 i, char* buffer);

char* FastHex32ToBuffer(uint32 i, char* buffer);

// at least 22 bytes long

inline char* FastIntToBuffer(int i, char* buffer) {

    return (sizeof(i) == 4 ? FastInt32ToBuffer(i, buffer) : FastInt64ToBuffer(i, buffer));

}

inline char* FastUIntToBuffer(unsigned int i, char* buffer) {

    return (sizeof(i) == 4 ? FastUInt32ToBuffer(i, buffer) : FastUInt64ToBuffer(i, buffer));

}

// ----------------------------------------------------------------------

// FastInt32ToBufferLeft()

// FastUInt32ToBufferLeft()

// FastInt64ToBufferLeft()

// FastUInt64ToBufferLeft()

//

// Like the Fast*ToBuffer() functions above, these are intended for speed.

// Unlike the Fast*ToBuffer() functions, however, these functions write

// their output to the beginning of the buffer (hence the name, as the

// output is left-aligned).  The caller is responsible for ensuring that

// the buffer has enough space to hold the output.

//

// Returns a pointer to the end of the string (i.e. the null character

// terminating the string).

// ----------------------------------------------------------------------

char* FastInt32ToBufferLeft(int32 i, char* buffer);   // at least 12 bytes

char* FastUInt32ToBufferLeft(uint32 i, char* buffer); // at least 12 bytes

char* FastInt64ToBufferLeft(int64 i, char* buffer);   // at least 22 bytes

char* FastUInt64ToBufferLeft(uint64 i, char* buffer); // at least 22 bytes

// Just define these in terms of the above.

inline char* FastUInt32ToBuffer(uint32 i, char* buffer) {

    FastUInt32ToBufferLeft(i, buffer);

    return buffer;

}

inline char* FastUInt64ToBuffer(uint64 i, char* buffer) {

    FastUInt64ToBufferLeft(i, buffer);

    return buffer;

}

// ----------------------------------------------------------------------

// HexDigitsPrefix()

//  returns 1 if buf is prefixed by "num_digits" of hex digits

//  returns 0 otherwise.

//  The function checks for '\0' for string termination.

// ----------------------------------------------------------------------

int HexDigitsPrefix(const char* buf, int num_digits);

// ----------------------------------------------------------------------

// ConsumeStrayLeadingZeroes

//    Eliminates all leading zeroes (unless the string itself is composed

//    of nothing but zeroes, in which case one is kept: 0...0 becomes 0).

void ConsumeStrayLeadingZeroes(string* str);

// ----------------------------------------------------------------------

// ParseLeadingInt32Value

//    A simple parser for int32 values. Returns the parsed value

//    if a valid integer is found; else returns deflt. It does not

//    check if str is entirely consumed.

//    This cannot handle decimal numbers with leading 0s, since they will be

//    treated as octal.  If you know it's decimal, use ParseLeadingDec32Value.

// --------------------------------------------------------------------

int32 ParseLeadingInt32Value(const char* str, int32 deflt);

inline int32 ParseLeadingInt32Value(const string& str, int32 deflt) {

    return ParseLeadingInt32Value(str.c_str(), deflt);

}

// ParseLeadingUInt32Value

//    A simple parser for uint32 values. Returns the parsed value

//    if a valid integer is found; else returns deflt. It does not

//    check if str is entirely consumed.

//    This cannot handle decimal numbers with leading 0s, since they will be

//    treated as octal.  If you know it's decimal, use ParseLeadingUDec32Value.

// --------------------------------------------------------------------

uint32 ParseLeadingUInt32Value(const char* str, uint32 deflt);

inline uint32 ParseLeadingUInt32Value(const string& str, uint32 deflt) {

    return ParseLeadingUInt32Value(str.c_str(), deflt);

}

// ----------------------------------------------------------------------

// ParseLeadingDec32Value

//    A simple parser for decimal int32 values. Returns the parsed value

//    if a valid integer is found; else returns deflt. It does not

//    check if str is entirely consumed.

//    The string passed in is treated as *10 based*.

//    This can handle strings with leading 0s.

//    See also: ParseLeadingDec64Value

// --------------------------------------------------------------------

int32 ParseLeadingDec32Value(const char* str, int32 deflt);

inline int32 ParseLeadingDec32Value(const string& str, int32 deflt) {

    return ParseLeadingDec32Value(str.c_str(), deflt);

}

// ParseLeadingUDec32Value

//    A simple parser for decimal uint32 values. Returns the parsed value

//    if a valid integer is found; else returns deflt. It does not

//    check if str is entirely consumed.

//    The string passed in is treated as *10 based*.

//    This can handle strings with leading 0s.

//    See also: ParseLeadingUDec64Value

// --------------------------------------------------------------------

uint32 ParseLeadingUDec32Value(const char* str, uint32 deflt);

inline uint32 ParseLeadingUDec32Value(const string& str, uint32 deflt) {

    return ParseLeadingUDec32Value(str.c_str(), deflt);

}

// ----------------------------------------------------------------------

// ParseLeadingUInt64Value

// ParseLeadingInt64Value

// ParseLeadingHex64Value

// ParseLeadingDec64Value

// ParseLeadingUDec64Value

//    A simple parser for long long values.

//    Returns the parsed value if a

//    valid integer is found; else returns deflt

// --------------------------------------------------------------------

uint64 ParseLeadingUInt64Value(const char* str, uint64 deflt);

inline uint64 ParseLeadingUInt64Value(const string& str, uint64 deflt) {

    return ParseLeadingUInt64Value(str.c_str(), deflt);

}

int64 ParseLeadingInt64Value(const char* str, int64 deflt);

inline int64 ParseLeadingInt64Value(const string& str, int64 deflt) {

    return ParseLeadingInt64Value(str.c_str(), deflt);

}

uint64 ParseLeadingHex64Value(const char* str, uint64 deflt);

inline uint64 ParseLeadingHex64Value(const string& str, uint64 deflt) {

    return ParseLeadingHex64Value(str.c_str(), deflt);

}

int64 ParseLeadingDec64Value(const char* str, int64 deflt);

inline int64 ParseLeadingDec64Value(const string& str, int64 deflt) {

    return ParseLeadingDec64Value(str.c_str(), deflt);

}

uint64 ParseLeadingUDec64Value(const char* str, uint64 deflt);

inline uint64 ParseLeadingUDec64Value(const string& str, uint64 deflt) {

    return ParseLeadingUDec64Value(str.c_str(), deflt);

}

// ----------------------------------------------------------------------

// ParseLeadingDoubleValue

//    A simple parser for double values. Returns the parsed value

//    if a valid double is found; else returns deflt. It does not

//    check if str is entirely consumed.

// --------------------------------------------------------------------

double ParseLeadingDoubleValue(const char* str, double deflt);

inline double ParseLeadingDoubleValue(const string& str, double deflt) {

    return ParseLeadingDoubleValue(str.c_str(), deflt);

}

// ----------------------------------------------------------------------

// ParseLeadingBoolValue()

//    A recognizer of boolean string values. Returns the parsed value

//    if a valid value is found; else returns deflt.  This skips leading

//    whitespace, is case insensitive, and recognizes these forms:

//    0/1, false/true, no/yes, n/y

// --------------------------------------------------------------------

bool ParseLeadingBoolValue(const char* str, bool deflt);

inline bool ParseLeadingBoolValue(const string& str, bool deflt) {

    return ParseLeadingBoolValue(str.c_str(), deflt);

}

// ----------------------------------------------------------------------

// AutoDigitStrCmp

// AutoDigitLessThan

// StrictAutoDigitLessThan

// autodigit_less

// autodigit_greater

// strict_autodigit_less

// strict_autodigit_greater

//    These are like less<string> and greater<string>, except when a

//    run of digits is encountered at corresponding points in the two

//    arguments.  Such digit strings are compared numerically instead

//    of lexicographically.  Therefore if you sort by

//    "autodigit_less", some machine names might get sorted as:

//        exaf1

//        exaf2

//        exaf10

//    When using "strict" comparison (AutoDigitStrCmp with the strict flag

//    set to true, or the strict version of the other functions),

//    strings that represent equal numbers will not be considered equal if

//    the string representations are not identical.  That is, "01" < "1" in

//    strict mode, but "01" == "1" otherwise.

// ----------------------------------------------------------------------

int AutoDigitStrCmp(const char* a, int alen, const char* b, int blen, bool strict);

bool AutoDigitLessThan(const char* a, int alen, const char* b, int blen);

bool StrictAutoDigitLessThan(const char* a, int alen, const char* b, int blen);

struct autodigit_less {

    bool operator()(const string& a, const string& b) const {

        return AutoDigitLessThan(a.data(), a.size(), b.data(), b.size());

    }

};

struct autodigit_greater {

    bool operator()(const string& a, const string& b) const {

        return AutoDigitLessThan(b.data(), b.size(), a.data(), a.size());

    }

};

struct strict_autodigit_less {

    bool operator()(const string& a, const string& b) const {

        return StrictAutoDigitLessThan(a.data(), a.size(), b.data(), b.size());

    }

};

struct strict_autodigit_greater {

    bool operator()(const string& a, const string& b) const {

        return StrictAutoDigitLessThan(b.data(), b.size(), a.data(), a.size());

    }

};

// ----------------------------------------------------------------------

// SimpleItoa()

//    Description: converts an integer to a string.

//    Faster than printf("%d").

//

//    Return value: string

// ----------------------------------------------------------------------

inline string SimpleItoa(int32 i) {

    char buf[16]; // Longest is -2147483648

    return string(buf, FastInt32ToBufferLeft(i, buf));

}

// We need this overload because otherwise SimpleItoa(5U) wouldn't compile.

inline string SimpleItoa(uint32 i) {

    char buf[16]; // Longest is 4294967295

    return string(buf, FastUInt32ToBufferLeft(i, buf));

}

inline string SimpleItoa(int64 i) {

    char buf[32]; // Longest is -9223372036854775808

    return string(buf, FastInt64ToBufferLeft(i, buf));

}

// We need this overload because otherwise SimpleItoa(5ULL) wouldn't compile.

inline string SimpleItoa(uint64 i) {

    char buf[32]; // Longest is 18446744073709551615

    return string(buf, FastUInt64ToBufferLeft(i, buf));

}

// SimpleAtoi converts a string to an integer.

// Uses safe_strto?() for actual parsing, so strict checking is

// applied, which is to say, the string must be a base-10 integer, optionally

// followed or preceded by whitespace, and value has to be in the range of

// the corresponding integer type.

//

// Returns true if parsing was successful.

template <typename int_type>

bool MUST_USE_RESULT SimpleAtoi(const char* s, int_type* out) {

    // Must be of integer type (not pointer type), with more than 16-bitwidth.

    COMPILE_ASSERT(sizeof(*out) == 4 || sizeof(*out) == 8, SimpleAtoiWorksWith32Or64BitInts);

    if (std::numeric_limits<int_type>::is_signed) { // Signed

        if (sizeof(*out) == 64 / 8) {               // 64-bit

            return safe_strto64(s, reinterpret_cast<int64*>(out));

        } else { // 32-bit

            return safe_strto32(s, reinterpret_cast<int32*>(out));

        }

    } else {                          // Unsigned

        if (sizeof(*out) == 64 / 8) { // 64-bit

            return safe_strtou64(s, reinterpret_cast<uint64*>(out));

        } else { // 32-bit

            return safe_strtou32(s, reinterpret_cast<uint32*>(out));

        }

    }

}

template <typename int_type>

bool MUST_USE_RESULT SimpleAtoi(const string& s, int_type* out) {

    return SimpleAtoi(s.c_str(), out);

}

// ----------------------------------------------------------------------

// SimpleDtoa()

// SimpleFtoa()

// DoubleToBuffer()

// FloatToBuffer()

//    Description: converts a double or float to a string which, if

//    passed to strtod(), will produce the exact same original double

//    (except in case of NaN; all NaNs are considered the same value).

//    We try to keep the string short but it's not guaranteed to be as

//    short as possible.

//

//    DoubleToBuffer() and FloatToBuffer() write the text to the given

//    buffer and return it.  The buffer must be at least

//    kDoubleToBufferSize bytes for doubles and kFloatToBufferSize

//    bytes for floats.  kFastToBufferSize is also guaranteed to be large

//    enough to hold either.

//

//    Return value: string

// ----------------------------------------------------------------------

string SimpleDtoa(double value);

string SimpleFtoa(float value);

int DoubleToBuffer(double i, int width, char* buffer);

int FloatToBuffer(float i, int width, char* buffer);

char* DoubleToBuffer(double i, char* buffer);

char* FloatToBuffer(float i, char* buffer);

int FastDoubleToBuffer(double i, char* buffer);

int FastFloatToBuffer(float i, char* buffer);

// In practice, doubles should never need more than 24 bytes and floats

// should never need more than 14 (including null terminators), but we

// overestimate to be safe.

static const int kDoubleToBufferSize = 32;

static const int kFloatToBufferSize = 24;

// ----------------------------------------------------------------------

// SimpleItoaWithCommas()

//    Description: converts an integer to a string.

//    Puts commas every 3 spaces.

//    Faster than printf("%d")?

//

//    Return value: string

// ----------------------------------------------------------------------

string SimpleItoaWithCommas(int32 i);

string SimpleItoaWithCommas(uint32 i);

string SimpleItoaWithCommas(int64 i);

string SimpleItoaWithCommas(uint64 i);

char* SimpleItoaWithCommas(int64_t i, char* buffer, int32_t buffer_size);

char* SimpleItoaWithCommas(__int128_t i, char* buffer, int32_t buffer_size);

// ----------------------------------------------------------------------

// ItoaKMGT()

//    Description: converts an integer to a string

//    Truncates values to K, G, M or T as appropriate

//    Opposite of atoi_kmgt()

//    e.g. 3000 -> 2K   57185920 -> 45M

//

//    Return value: string

//

// AccurateItoaKMGT()

//    Description: preserve accuracy

// ----------------------------------------------------------------------

string ItoaKMGT(int64 i);

string AccurateItoaKMGT(int64 i);

// ----------------------------------------------------------------------

// ParseDoubleRange()

//    Parse an expression in 'text' of the form: <double><sep><double>

//    where <double> may be a double-precision number and <sep> is a

//    single char or "..", and must be one of the chars in parameter

//    'separators', which may contain '-' or '.' (which means "..") or

//    any chars not allowed in a double. If allow_unbounded_markers,

//    <double> may also be a '?' to indicate unboundedness (if on the

//    left of <sep>, means unbounded below; if on the right, means

//    unbounded above). Depending on num_required_bounds, which may be

//    0, 1, or 2, <double> may also be the empty string, indicating

//    unboundedness. If require_separator is false, then a single

//    <double> is acceptable and is parsed as a range bounded from

//    below. We also check that the character following the range must

//    be in acceptable_terminators. If null_terminator_ok, then it is

//    also OK if the range ends in \0 or after len chars. If

//    allow_currency is true, the first <double> may be optionally

//    preceded by a '$', in which case *is_currency will be true, and

//    the second <double> may similarly be preceded by a '$'. In these

//    cases, the '$' will be ignored (otherwise it's an error). If

//    allow_comparators is true, the expression in 'text' may also be

//    of the form <comparator><double>, where <comparator> is '<' or

//    '>' or '<=' or '>='. separators and require_separator are

//    ignored in this format, but all other parameters function as for

//    the first format. Return true if the expression parsed

//    successfully; false otherwise. If successful, output params are:

//    'end', which points to the char just beyond the expression;

//    'from' and 'to' are set to the values of the <double>s, and are

//    -inf and inf (or unchanged, depending on dont_modify_unbounded)

//    if unbounded. Output params are undefined if false is

//    returned. len is the input length, or -1 if text is

//    '\0'-terminated, which is more efficient.

// ----------------------------------------------------------------------

struct DoubleRangeOptions {

    const char* separators = nullptr;

    bool require_separator;

    const char* acceptable_terminators = nullptr;

    bool null_terminator_ok;

    bool allow_unbounded_markers;

    uint32 num_required_bounds;

    bool dont_modify_unbounded;

    bool allow_currency;

    bool allow_comparators;

};

// NOTE: The instruction below creates a Module titled

// NumbersFunctions within the auto-generated Doxygen documentation.

// This instruction is needed to expose global functions that are not

// within a namespace.

//

bool ParseDoubleRange(const char* text, int len, const char** end, double* from, double* to,

                      bool* is_currency, const DoubleRangeOptions& opts);

// END DOXYGEN SplitFunctions grouping

/* @} */

// These functions are deprecated.

// Do not use in new code.

// // DEPRECATED(wadetregaskis).  Just call StringPrintf or SimpleFtoa.

// string FloatToString(float f, const char* format);

// // DEPRECATED(wadetregaskis).  Just call StringPrintf or SimpleItoa.

// string IntToString(int i, const char* format);

// // DEPRECATED(wadetregaskis).  Just call StringPrintf or SimpleItoa.

// string Int64ToString(int64 i64, const char* format);

// // DEPRECATED(wadetregaskis).  Just call StringPrintf or SimpleItoa.

// string UInt64ToString(uint64 ui64, const char* format);

// // DEPRECATED(wadetregaskis).  Just call StringPrintf.

// inline string FloatToString(float f) {

//   return StringPrintf("%7f", f);

// }

// // DEPRECATED(wadetregaskis).  Just call StringPrintf.

// inline string IntToString(int i) {

//   return StringPrintf("%7d", i);

// }

// // DEPRECATED(wadetregaskis).  Just call StringPrintf.

// inline string Int64ToString(int64 i64) {

//   return StringPrintf("%7" PRId64, i64);

// }

// // DEPRECATED(wadetregaskis).  Just call StringPrintf.

// inline string UInt64ToString(uint64 ui64) {

//   return StringPrintf("%7" PRIu64, ui64);

// }