ladybird/Userland/Libraries/LibLocale/DateTimeFormat.cpp
Timothy Flynn 970e9df245 LibLocale: Remove "else" after "if" statements that always return
Mostly just to keep clangd quiet.
2023-01-27 18:00:17 +00:00

337 lines
12 KiB
C++

/*
* Copyright (c) 2021-2023, Tim Flynn <trflynn89@serenityos.org>
*
* SPDX-License-Identifier: BSD-2-Clause
*/
#include <AK/Array.h>
#include <AK/StringBuilder.h>
#include <LibLocale/DateTimeFormat.h>
#include <LibLocale/Locale.h>
#include <LibLocale/NumberFormat.h>
#include <stdlib.h>
namespace Locale {
HourCycle hour_cycle_from_string(StringView hour_cycle)
{
if (hour_cycle == "h11"sv)
return HourCycle::H11;
if (hour_cycle == "h12"sv)
return HourCycle::H12;
if (hour_cycle == "h23"sv)
return HourCycle::H23;
if (hour_cycle == "h24"sv)
return HourCycle::H24;
VERIFY_NOT_REACHED();
}
StringView hour_cycle_to_string(HourCycle hour_cycle)
{
switch (hour_cycle) {
case HourCycle::H11:
return "h11"sv;
case HourCycle::H12:
return "h12"sv;
case HourCycle::H23:
return "h23"sv;
case HourCycle::H24:
return "h24"sv;
default:
VERIFY_NOT_REACHED();
}
}
CalendarPatternStyle calendar_pattern_style_from_string(StringView style)
{
if (style == "narrow"sv)
return CalendarPatternStyle::Narrow;
if (style == "short"sv)
return CalendarPatternStyle::Short;
if (style == "long"sv)
return CalendarPatternStyle::Long;
if (style == "numeric"sv)
return CalendarPatternStyle::Numeric;
if (style == "2-digit"sv)
return CalendarPatternStyle::TwoDigit;
if (style == "shortOffset"sv)
return CalendarPatternStyle::ShortOffset;
if (style == "longOffset"sv)
return CalendarPatternStyle::LongOffset;
if (style == "shortGeneric"sv)
return CalendarPatternStyle::ShortGeneric;
if (style == "longGeneric"sv)
return CalendarPatternStyle::LongGeneric;
VERIFY_NOT_REACHED();
}
StringView calendar_pattern_style_to_string(CalendarPatternStyle style)
{
switch (style) {
case CalendarPatternStyle::Narrow:
return "narrow"sv;
case CalendarPatternStyle::Short:
return "short"sv;
case CalendarPatternStyle::Long:
return "long"sv;
case CalendarPatternStyle::Numeric:
return "numeric"sv;
case CalendarPatternStyle::TwoDigit:
return "2-digit"sv;
case CalendarPatternStyle::ShortOffset:
return "shortOffset"sv;
case CalendarPatternStyle::LongOffset:
return "longOffset"sv;
case CalendarPatternStyle::ShortGeneric:
return "shortGeneric"sv;
case CalendarPatternStyle::LongGeneric:
return "longGeneric"sv;
default:
VERIFY_NOT_REACHED();
}
}
Optional<HourCycleRegion> __attribute__((weak)) hour_cycle_region_from_string(StringView) { return {}; }
Vector<HourCycle> __attribute__((weak)) get_regional_hour_cycles(StringView) { return {}; }
template<typename GetRegionalValues>
static auto find_regional_values_for_locale(StringView locale, GetRegionalValues&& get_regional_values)
{
auto has_value = [](auto const& container) {
if constexpr (requires { container.has_value(); })
return container.has_value();
else
return !container.is_empty();
};
if (auto regional_values = get_regional_values(locale); has_value(regional_values))
return regional_values;
auto return_default_values = [&]() { return get_regional_values("001"sv); };
auto language = parse_unicode_language_id(locale).release_value_but_fixme_should_propagate_errors();
if (!language.has_value())
return return_default_values();
if (!language->region.has_value())
language = add_likely_subtags(*language).release_value_but_fixme_should_propagate_errors();
if (!language.has_value() || !language->region.has_value())
return return_default_values();
if (auto regional_values = get_regional_values(*language->region); has_value(regional_values))
return regional_values;
return return_default_values();
}
// https://unicode.org/reports/tr35/tr35-dates.html#Date_Field_Symbol_Table
Vector<HourCycle> get_locale_hour_cycles(StringView locale)
{
return find_regional_values_for_locale(locale, get_regional_hour_cycles);
}
Optional<HourCycle> get_default_regional_hour_cycle(StringView locale)
{
if (auto hour_cycles = get_locale_hour_cycles(locale); !hour_cycles.is_empty())
return hour_cycles.first();
return {};
}
Optional<MinimumDaysRegion> __attribute__((weak)) minimum_days_region_from_string(StringView) { return {}; }
Optional<u8> __attribute__((weak)) get_regional_minimum_days(StringView) { return {}; }
Optional<u8> get_locale_minimum_days(StringView locale)
{
return find_regional_values_for_locale(locale, get_regional_minimum_days);
}
Optional<FirstDayRegion> __attribute__((weak)) first_day_region_from_string(StringView) { return {}; }
Optional<Weekday> __attribute__((weak)) get_regional_first_day(StringView) { return {}; }
Optional<Weekday> get_locale_first_day(StringView locale)
{
return find_regional_values_for_locale(locale, get_regional_first_day);
}
Optional<WeekendStartRegion> __attribute__((weak)) weekend_start_region_from_string(StringView) { return {}; }
Optional<Weekday> __attribute__((weak)) get_regional_weekend_start(StringView) { return {}; }
Optional<Weekday> get_locale_weekend_start(StringView locale)
{
return find_regional_values_for_locale(locale, get_regional_weekend_start);
}
Optional<WeekendEndRegion> __attribute__((weak)) weekend_end_region_from_string(StringView) { return {}; }
Optional<Weekday> __attribute__((weak)) get_regional_weekend_end(StringView) { return {}; }
Optional<Weekday> get_locale_weekend_end(StringView locale)
{
return find_regional_values_for_locale(locale, get_regional_weekend_end);
}
DeprecatedString combine_skeletons(StringView first, StringView second)
{
// https://unicode.org/reports/tr35/tr35-dates.html#availableFormats_appendItems
constexpr auto field_order = Array {
"G"sv, // Era
"yYuUr"sv, // Year
"ML"sv, // Month
"dDFg"sv, // Day
"Eec"sv, // Weekday
"abB"sv, // Period
"hHKk"sv, // Hour
"m"sv, // Minute
"sSA"sv, // Second
"zZOvVXx"sv, // Zone
};
StringBuilder builder;
auto append_from_skeleton = [&](auto skeleton, auto ch) {
auto first_index = skeleton.find(ch);
if (!first_index.has_value())
return false;
auto last_index = skeleton.find_last(ch);
builder.append(skeleton.substring_view(*first_index, *last_index - *first_index + 1));
return true;
};
for (auto fields : field_order) {
for (auto ch : fields) {
if (append_from_skeleton(first, ch))
break;
if (append_from_skeleton(second, ch))
break;
}
}
return builder.build();
}
Optional<CalendarFormat> __attribute__((weak)) get_calendar_date_format(StringView, StringView) { return {}; }
Optional<CalendarFormat> __attribute__((weak)) get_calendar_time_format(StringView, StringView) { return {}; }
Optional<CalendarFormat> __attribute__((weak)) get_calendar_date_time_format(StringView, StringView) { return {}; }
Optional<CalendarFormat> get_calendar_format(StringView locale, StringView calendar, CalendarFormatType type)
{
switch (type) {
case CalendarFormatType::Date:
return get_calendar_date_format(locale, calendar);
case CalendarFormatType::Time:
return get_calendar_time_format(locale, calendar);
case CalendarFormatType::DateTime:
return get_calendar_date_time_format(locale, calendar);
default:
VERIFY_NOT_REACHED();
}
}
Vector<CalendarPattern> __attribute__((weak)) get_calendar_available_formats(StringView, StringView) { return {}; }
Optional<CalendarRangePattern> __attribute__((weak)) get_calendar_default_range_format(StringView, StringView) { return {}; }
Vector<CalendarRangePattern> __attribute__((weak)) get_calendar_range_formats(StringView, StringView, StringView) { return {}; }
Vector<CalendarRangePattern> __attribute__((weak)) get_calendar_range12_formats(StringView, StringView, StringView) { return {}; }
Optional<StringView> __attribute__((weak)) get_calendar_era_symbol(StringView, StringView, CalendarPatternStyle, Era) { return {}; }
Optional<StringView> __attribute__((weak)) get_calendar_month_symbol(StringView, StringView, CalendarPatternStyle, Month) { return {}; }
Optional<StringView> __attribute__((weak)) get_calendar_weekday_symbol(StringView, StringView, CalendarPatternStyle, Weekday) { return {}; }
Optional<StringView> __attribute__((weak)) get_calendar_day_period_symbol(StringView, StringView, CalendarPatternStyle, DayPeriod) { return {}; }
Optional<StringView> __attribute__((weak)) get_calendar_day_period_symbol_for_hour(StringView, StringView, CalendarPatternStyle, u8) { return {}; }
Optional<StringView> __attribute__((weak)) get_time_zone_name(StringView, StringView, CalendarPatternStyle, TimeZone::InDST) { return {}; }
Optional<TimeZoneFormat> __attribute__((weak)) get_time_zone_format(StringView) { return {}; }
static Optional<DeprecatedString> format_time_zone_offset(StringView locale, CalendarPatternStyle style, i64 offset_seconds)
{
auto formats = get_time_zone_format(locale);
if (!formats.has_value())
return {};
auto number_system = get_preferred_keyword_value_for_locale(locale, "nu"sv);
if (!number_system.has_value())
return {};
if (offset_seconds == 0)
return formats->gmt_zero_format;
auto sign = offset_seconds > 0 ? formats->symbol_ahead_sign : formats->symbol_behind_sign;
auto separator = offset_seconds > 0 ? formats->symbol_ahead_separator : formats->symbol_behind_separator;
offset_seconds = llabs(offset_seconds);
auto offset_hours = offset_seconds / 3'600;
offset_seconds %= 3'600;
auto offset_minutes = offset_seconds / 60;
offset_seconds %= 60;
StringBuilder builder;
builder.append(sign);
switch (style) {
// The long format always uses 2-digit hours field and minutes field, with optional 2-digit seconds field.
case CalendarPatternStyle::LongOffset:
builder.appendff("{:02}{}{:02}", offset_hours, separator, offset_minutes);
if (offset_seconds > 0)
builder.appendff("{}{:02}", separator, offset_seconds);
break;
// The short format is intended for the shortest representation and uses hour fields without leading zero, with optional 2-digit minutes and seconds fields.
case CalendarPatternStyle::ShortOffset:
builder.appendff("{}", offset_hours);
if (offset_minutes > 0) {
builder.appendff("{}{:02}", separator, offset_minutes);
if (offset_seconds > 0)
builder.appendff("{}{:02}", separator, offset_seconds);
}
break;
default:
VERIFY_NOT_REACHED();
}
// The digits used for hours, minutes and seconds fields in this format are the locale's default decimal digits.
auto result = replace_digits_for_number_system(*number_system, builder.build()).release_value_but_fixme_should_propagate_errors();
return formats->gmt_format.replace("{0}"sv, result, ReplaceMode::FirstOnly);
}
// https://unicode.org/reports/tr35/tr35-dates.html#Time_Zone_Format_Terminology
DeprecatedString format_time_zone(StringView locale, StringView time_zone, CalendarPatternStyle style, AK::Time time)
{
auto offset = TimeZone::get_time_zone_offset(time_zone, time);
if (!offset.has_value())
return time_zone;
switch (style) {
case CalendarPatternStyle::Short:
case CalendarPatternStyle::Long:
case CalendarPatternStyle::ShortGeneric:
case CalendarPatternStyle::LongGeneric:
if (auto name = get_time_zone_name(locale, time_zone, style, offset->in_dst); name.has_value())
return *name;
break;
case CalendarPatternStyle::ShortOffset:
case CalendarPatternStyle::LongOffset:
return format_time_zone_offset(locale, style, offset->seconds).value_or(time_zone);
default:
VERIFY_NOT_REACHED();
}
// If more styles are added, consult the following table to ensure always falling back to GMT offset is still correct:
// https://unicode.org/reports/tr35/tr35-dates.html#dfst-zone
switch (style) {
case CalendarPatternStyle::Short:
case CalendarPatternStyle::ShortGeneric:
return format_time_zone(locale, time_zone, CalendarPatternStyle::ShortOffset, time);
case CalendarPatternStyle::Long:
case CalendarPatternStyle::LongGeneric:
return format_time_zone(locale, time_zone, CalendarPatternStyle::LongOffset, time);
default:
VERIFY_NOT_REACHED();
}
}
}