/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*-
* vim: set ts=8 sts=2 et sw=2 tw=80:
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */
#ifndef builtin_temporal_Era_h
#define builtin_temporal_Era_h
#include "mozilla/Assertions.h"
#include "mozilla/MathAlgorithms.h"
#include <initializer_list>
#include <stddef.h>
#include <stdint.h>
#include <string_view>
#include "jstypes.h"
#include "builtin/temporal/Calendar.h"
#include "builtin/temporal/Crash.h"
namespace js::temporal {
enum class EraCode {
// The standard era of a calendar.
Standard,
// The era before the standard era of a calendar.
Inverse,
// Named Japanese eras.
Meiji,
Taisho,
Showa,
Heisei,
Reiwa,
};
// static variables in constexpr functions requires C++23 support, so we can't
// declare the eras directly in CalendarEras.
namespace eras {
inline constexpr
auto Standard = {EraCode::Standard};
inline constexpr
auto StandardInverse = {EraCode::Standard, EraCode::Inverse};
inline constexpr
auto Japanese = {
EraCode::Standard, EraCode::Inverse,
EraCode::Meiji, EraCode::Taisho, EraCode::Showa,
EraCode::Heisei, EraCode::Reiwa,
};
// https://tc39.es/proposal-intl-era-monthcode/#table-eras
//
// Calendars which don't use eras were omitted.
namespace names {
using namespace std::literals;
// Empty placeholder.
inline constexpr
auto Empty = {
""sv,
};
inline constexpr
auto Coptic = {
"coptic"sv,
};
inline constexpr
auto CopticInverse = {
"coptic-inverse"sv,
};
inline constexpr
auto Ethiopian = {
"ethiopic"sv,
"incar"sv,
};
inline constexpr
auto EthiopianInverse = {
"ethioaa"sv,
"ethiopic-amete-alem"sv,
"mundi"sv,
};
inline constexpr
auto Gregorian = {
"gregory"sv,
"ce"sv,
"ad"sv,
};
inline constexpr
auto GregorianInverse = {
"gregory-inverse"sv,
"bc"sv,
"bce"sv,
};
inline constexpr
auto Japanese = {
"japanese"sv,
"gregory"sv,
"ad"sv,
"ce"sv,
};
inline constexpr
auto JapaneseInverse = {
"japanese-inverse"sv,
"gregory-inverse"sv,
"bc"sv,
"bce"sv,
};
inline constexpr
auto JapaneseMeiji = {
"meiji"sv,
};
inline constexpr
auto JapaneseTaisho = {
"taisho"sv,
};
inline constexpr
auto JapaneseShowa = {
"showa"sv,
};
inline constexpr
auto JapaneseHeisei = {
"heisei"sv,
};
inline constexpr
auto JapaneseReiwa = {
"reiwa"sv,
};
inline constexpr
auto ROC = {
"roc"sv,
"minguo"sv,
};
inline constexpr
auto ROCInverse = {
"roc-inverse"sv,
"before-roc"sv,
};
}
// namespace names
}
// namespace eras
constexpr
auto& CalendarEras(CalendarId id) {
switch (id) {
case CalendarId::ISO8601:
case CalendarId::Buddhist:
case CalendarId::Chinese:
case CalendarId::Dangi:
case CalendarId::EthiopianAmeteAlem:
case CalendarId::Hebrew:
case CalendarId::Indian:
case CalendarId::Islamic:
case CalendarId::IslamicCivil:
case CalendarId::IslamicRGSA:
case CalendarId::IslamicTabular:
case CalendarId::IslamicUmmAlQura:
case CalendarId::Persian:
return eras::Standard;
case CalendarId::Coptic:
case CalendarId::Ethiopian:
case CalendarId::Gregorian:
case CalendarId::ROC:
return eras::StandardInverse;
case CalendarId::Japanese:
return eras::Japanese;
}
JS_CONSTEXPR_CRASH(
"invalid calendar id");
}
constexpr
bool CalendarEraRelevant(CalendarId calendar) {
return CalendarEras(calendar).size() > 1;
}
constexpr
auto& CalendarEraNames(CalendarId calendar, EraCode era) {
switch (calendar) {
case CalendarId::ISO8601:
case CalendarId::Buddhist:
case CalendarId::Chinese:
case CalendarId::Dangi:
case CalendarId::EthiopianAmeteAlem:
case CalendarId::Hebrew:
case CalendarId::Indian:
case CalendarId::Islamic:
case CalendarId::IslamicCivil:
case CalendarId::IslamicRGSA:
case CalendarId::IslamicTabular:
case CalendarId::IslamicUmmAlQura:
case CalendarId::Persian:
return eras::names::Empty;
case CalendarId::Coptic: {
MOZ_ASSERT(era == EraCode::Standard || era == EraCode::Inverse);
return era == EraCode::Standard ? eras::names::Coptic
: eras::names::CopticInverse;
}
case CalendarId::Ethiopian: {
MOZ_ASSERT(era == EraCode::Standard || era == EraCode::Inverse);
return era == EraCode::Standard ? eras::names::Ethiopian
: eras::names::EthiopianInverse;
}
case CalendarId::Gregorian: {
MOZ_ASSERT(era == EraCode::Standard || era == EraCode::Inverse);
return era == EraCode::Standard ? eras::names::Gregorian
: eras::names::GregorianInverse;
}
case CalendarId::Japanese: {
switch (era) {
case EraCode::Standard:
return eras::names::Japanese;
case EraCode::Inverse:
return eras::names::JapaneseInverse;
case EraCode::Meiji:
return eras::names::JapaneseMeiji;
case EraCode::Taisho:
return eras::names::JapaneseTaisho;
case EraCode::Showa:
return eras::names::JapaneseShowa;
case EraCode::Heisei:
return eras::names::JapaneseHeisei;
case EraCode::Reiwa:
return eras::names::JapaneseReiwa;
}
break;
}
case CalendarId::ROC: {
MOZ_ASSERT(era == EraCode::Standard || era == EraCode::Inverse);
return era == EraCode::Standard ? eras::names::ROC
: eras::names::ROCInverse;
}
}
JS_CONSTEXPR_CRASH(
"invalid era");
}
constexpr
auto CalendarEraName(CalendarId calendar, EraCode era) {
auto& names = CalendarEraNames(calendar, era);
MOZ_ASSERT(names.size() > 0);
return *names.begin();
}
constexpr
bool CalendarEraStartsAtYearBoundary(CalendarId id) {
switch (id) {
// Calendar system which use a single era.
case CalendarId::ISO8601:
case CalendarId::Buddhist:
case CalendarId::Chinese:
case CalendarId::Dangi:
case CalendarId::EthiopianAmeteAlem:
case CalendarId::Hebrew:
case CalendarId::Indian:
case CalendarId::Islamic:
case CalendarId::IslamicCivil:
case CalendarId::IslamicRGSA:
case CalendarId::IslamicTabular:
case CalendarId::IslamicUmmAlQura:
case CalendarId::Persian:
return true;
// Calendar system which use multiple eras, but each era starts at a year
// boundary.
case CalendarId::Coptic:
case CalendarId::Ethiopian:
case CalendarId::Gregorian:
case CalendarId::ROC:
return true;
// Calendar system which use multiple eras and eras can start within a year.
case CalendarId::Japanese:
return false;
}
JS_CONSTEXPR_CRASH(
"invalid calendar id");
}
constexpr
bool CalendarEraStartsAtYearBoundary(CalendarId id, EraCode era) {
MOZ_ASSERT_IF(id != CalendarId::Japanese,
CalendarEraStartsAtYearBoundary(id));
return era == EraCode::Standard || era == EraCode::Inverse;
}
struct EraYear {
EraCode era = EraCode::Standard;
int32_t year = 0;
};
constexpr EraYear CalendarEraYear(CalendarId id, int32_t year) {
if (year > 0 || !CalendarEraRelevant(id)) {
return EraYear{EraCode::Standard, year};
}
return EraYear{EraCode::Inverse, int32_t(mozilla::Abs(year) + 1)};
}
}
// namespace js::temporal
#endif /* builtin_temporal_Era_h */
