LibUnicode: Generate per-region week data

This includes:
* The minimum number of days in a week for that week to count as the
  first week of a new year.
* The day to be shown as the first day of the week in a calendar.
* The start/end days of the weekend.

Like the existing hour cycle data, week data is presented per-region in
the CLDR, rather than per-locale. The method to add likely subtags to a
locale to perform region lookups is the same.

The list of regions in the CLDR for hour cycle, minimum days, first day,
and weekend days are quite different. So rather than changing the
existing HourCycleRegion enum to a generic Region enum, we generate
separate enums for each of the week data fields. This allows each lookup
into these fields to remain simple array-based index access, without any
"jumps" for regions that don't have CLDR data for a field.

Meta/Lagom/Tools/CodeGenerators/LibUnicode/GenerateUnicodeDateTimeFormat.cpp

@@ -7,6 +7,7 @@
 #include "GeneratorUtil.h"
 #include <AK/AllOf.h>
 #include <AK/CharacterTypes.h>
+#include <AK/Find.h>
 #include <AK/Format.h>
 #include <AK/GenericLexer.h>
 #include <AK/HashFunctions.h>
@@ -565,6 +566,18 @@ struct UnicodeLocaleData {
     HashMap<String, HourCycleListIndexType> hour_cycles;
     Vector<String> hour_cycle_regions;
 
+    HashMap<String, u8> minimum_days;
+    Vector<String> minimum_days_regions;
+
+    HashMap<String, Unicode::Weekday> first_day;
+    Vector<String> first_day_regions;
+
+    HashMap<String, Unicode::Weekday> weekend_start;
+    Vector<String> weekend_start_regions;
+
+    HashMap<String, Unicode::Weekday> weekend_end;
+    Vector<String> weekend_end_regions;
+
     HashMap<String, Vector<TimeZone::TimeZone>> meta_zones;
     Vector<String> time_zones { "UTC"sv };
 
@@ -640,6 +653,71 @@ static ErrorOr<void> parse_hour_cycles(String core_path, UnicodeLocaleData& loca
     return {};
 }
 
+static ErrorOr<void> parse_week_data(String core_path, UnicodeLocaleData& locale_data)
+{
+    // https://unicode.org/reports/tr35/tr35-dates.html#Week_Data
+    LexicalPath week_data_path(move(core_path));
+    week_data_path = week_data_path.append("supplemental"sv);
+    week_data_path = week_data_path.append("weekData.json"sv);
+
+    auto week_data = TRY(read_json_file(week_data_path.string()));
+    auto const& supplemental_object = week_data.as_object().get("supplemental"sv);
+    auto const& week_data_object = supplemental_object.as_object().get("weekData"sv);
+
+    auto parse_weekday = [](StringView day) -> Unicode::Weekday {
+        if (day == "sun"sv)
+            return Unicode::Weekday::Sunday;
+        if (day == "mon"sv)
+            return Unicode::Weekday::Monday;
+        if (day == "tue"sv)
+            return Unicode::Weekday::Tuesday;
+        if (day == "wed"sv)
+            return Unicode::Weekday::Wednesday;
+        if (day == "thu"sv)
+            return Unicode::Weekday::Thursday;
+        if (day == "fri"sv)
+            return Unicode::Weekday::Friday;
+        if (day == "sat"sv)
+            return Unicode::Weekday::Saturday;
+        VERIFY_NOT_REACHED();
+    };
+
+    auto parse_regional_weekdays = [&](auto const& region, auto const& weekday, auto& weekdays_map, auto& weekday_regions) {
+        if (region.ends_with("alt-variant"sv))
+            return;
+
+        weekdays_map.set(region, parse_weekday(weekday));
+
+        if (!weekday_regions.contains_slow(region))
+            weekday_regions.append(region);
+    };
+
+    auto const& minimum_days_object = week_data_object.as_object().get("minDays"sv);
+    auto const& first_day_object = week_data_object.as_object().get("firstDay"sv);
+    auto const& weekend_start_object = week_data_object.as_object().get("weekendStart"sv);
+    auto const& weekend_end_object = week_data_object.as_object().get("weekendEnd"sv);
+
+    minimum_days_object.as_object().for_each_member([&](auto const& region, auto const& value) {
+        auto minimum_days = value.as_string().template to_uint<u8>();
+        locale_data.minimum_days.set(region, *minimum_days);
+
+        if (!locale_data.minimum_days_regions.contains_slow(region))
+            locale_data.minimum_days_regions.append(region);
+    });
+
+    first_day_object.as_object().for_each_member([&](auto const& region, auto const& value) {
+        parse_regional_weekdays(region, value.as_string(), locale_data.first_day, locale_data.first_day_regions);
+    });
+    weekend_start_object.as_object().for_each_member([&](auto const& region, auto const& value) {
+        parse_regional_weekdays(region, value.as_string(), locale_data.weekend_start, locale_data.weekend_start_regions);
+    });
+    weekend_end_object.as_object().for_each_member([&](auto const& region, auto const& value) {
+        parse_regional_weekdays(region, value.as_string(), locale_data.weekend_end, locale_data.weekend_end_regions);
+    });
+
+    return {};
+}
+
 static ErrorOr<void> parse_meta_zones(String core_path, UnicodeLocaleData& locale_data)
 {
     // https://unicode.org/reports/tr35/tr35-dates.html#Metazones
@@ -1568,6 +1646,7 @@ static ErrorOr<void> parse_day_periods(String core_path, UnicodeLocaleData& loca
 static ErrorOr<void> parse_all_locales(String core_path, String dates_path, UnicodeLocaleData& locale_data)
 {
     TRY(parse_hour_cycles(core_path, locale_data));
+    TRY(parse_week_data(core_path, locale_data));
     TRY(parse_meta_zones(core_path, locale_data));
 
     auto dates_iterator = TRY(path_to_dir_iterator(move(dates_path)));
@@ -1631,6 +1710,10 @@ namespace Unicode {
 
     generate_enum(generator, format_identifier, "Calendar"sv, {}, locale_data.calendars);
     generate_enum(generator, format_identifier, "HourCycleRegion"sv, {}, locale_data.hour_cycle_regions);
+    generate_enum(generator, format_identifier, "MinimumDaysRegion"sv, {}, locale_data.minimum_days_regions);
+    generate_enum(generator, format_identifier, "FirstDayRegion"sv, {}, locale_data.first_day_regions);
+    generate_enum(generator, format_identifier, "WeekendStartRegion"sv, {}, locale_data.weekend_start_regions);
+    generate_enum(generator, format_identifier, "WeekendEndRegion"sv, {}, locale_data.weekend_end_regions);
 
     generator.append(R"~~~(
 }
@@ -1912,6 +1995,10 @@ static constexpr Array<@type@, @size@> @name@ { {)~~~");
     append_mapping(locales, locale_data.locales, s_time_zone_format_index_type, "s_locale_time_zone_formats"sv, [](auto const& locale) { return locale.time_zone_formats; });
     append_mapping(locales, locale_data.locales, s_day_period_index_type, "s_locale_day_periods"sv, [](auto const& locale) { return locale.day_periods; });
     append_mapping(locale_data.hour_cycle_regions, locale_data.hour_cycles, s_hour_cycle_list_index_type, "s_hour_cycles"sv, [](auto const& hour_cycles) { return hour_cycles; });
+    append_mapping(locale_data.minimum_days_regions, locale_data.minimum_days, "u8"sv, "s_minimum_days"sv, [](auto minimum_days) { return minimum_days; });
+    append_mapping(locale_data.first_day_regions, locale_data.first_day, "u8"sv, "s_first_day"sv, [](auto first_day) { return to_underlying(first_day); });
+    append_mapping(locale_data.weekend_start_regions, locale_data.weekend_start, "u8"sv, "s_weekend_start"sv, [](auto weekend_start) { return to_underlying(weekend_start); });
+    append_mapping(locale_data.weekend_end_regions, locale_data.weekend_end, "u8"sv, "s_weekend_end"sv, [](auto weekend_end) { return to_underlying(weekend_end); });
     generator.append("\n");
 
     auto append_from_string = [&](StringView enum_title, StringView enum_snake, auto const& values, Vector<Alias> const& aliases = {}) {
@@ -1927,6 +2014,10 @@ static constexpr Array<@type@, @size@> @name@ { {)~~~");
     };
 
     append_from_string("HourCycleRegion"sv, "hour_cycle_region"sv, locale_data.hour_cycle_regions);
+    append_from_string("MinimumDaysRegion"sv, "minimum_days_region"sv, locale_data.minimum_days_regions);
+    append_from_string("FirstDayRegion"sv, "first_day_region"sv, locale_data.first_day_regions);
+    append_from_string("WeekendStartRegion"sv, "weekend_start_region"sv, locale_data.weekend_start_regions);
+    append_from_string("WeekendEndRegion"sv, "weekend_end_region"sv, locale_data.weekend_end_regions);
 
     generator.append(R"~~~(
 static Optional<Calendar> keyword_to_calendar(KeywordCalendar keyword)
@@ -1965,7 +2056,33 @@ Vector<HourCycle> get_regional_hour_cycles(StringView region)
 
     return hour_cycles;
 }
+)~~~");
 
+    auto append_regional_lookup = [&](StringView return_type, StringView lookup_type) {
+        generator.set("return_type", return_type);
+        generator.set("lookup_type", lookup_type);
+
+        generator.append(R"~~~(
+Optional<@return_type@> get_regional_@lookup_type@(StringView region)
+{
+    auto region_value = @lookup_type@_region_from_string(region);
+    if (!region_value.has_value())
+        return {};
+
+    auto region_index = to_underlying(*region_value);
+    auto @lookup_type@ = s_@lookup_type@.at(region_index);
+
+    return static_cast<@return_type@>(@lookup_type@);
+}
+)~~~");
+    };
+
+    append_regional_lookup("u8"sv, "minimum_days"sv);
+    append_regional_lookup("Unicode::Weekday"sv, "first_day"sv);
+    append_regional_lookup("Unicode::Weekday"sv, "weekend_start"sv);
+    append_regional_lookup("Unicode::Weekday"sv, "weekend_end"sv);
+
+    generator.append(R"~~~(
 static CalendarData const* find_calendar_data(StringView locale, StringView calendar)
 {
     auto locale_value = locale_from_string(locale);

Userland/Libraries/LibUnicode/DateTimeFormat.cpp

@@ -94,27 +94,40 @@ StringView calendar_pattern_style_to_string(CalendarPatternStyle style)
 Optional<HourCycleRegion> __attribute__((weak)) hour_cycle_region_from_string(StringView) { return {}; }
 Vector<HourCycle> __attribute__((weak)) get_regional_hour_cycles(StringView) { return {}; }
 
-// https://unicode.org/reports/tr35/tr35-dates.html#Date_Field_Symbol_Table
-Vector<Unicode::HourCycle> get_locale_hour_cycles(StringView locale)
+template<typename GetRegionalValues>
+static auto find_regional_values_for_locale(StringView locale, GetRegionalValues&& get_regional_values)
 {
-    if (auto hour_cycles = get_regional_hour_cycles(locale); !hour_cycles.is_empty())
-        return hour_cycles;
+    auto has_value = [](auto const& container) {
+        if constexpr (requires { container.has_value(); })
+            return container.has_value();
+        else
+            return !container.is_empty();
+    };
 
-    auto return_default_hour_cycles = [&]() { return get_regional_hour_cycles("001"sv); };
+    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);
     if (!language.has_value())
-        return return_default_hour_cycles();
+        return return_default_values();
 
     if (!language->region.has_value())
         language = add_likely_subtags(*language);
     if (!language.has_value() || !language->region.has_value())
-        return return_default_hour_cycles();
+        return return_default_values();
 
-    if (auto hour_cycles = get_regional_hour_cycles(*language->region); !hour_cycles.is_empty())
-        return hour_cycles;
+    if (auto regional_values = get_regional_values(*language->region); has_value(regional_values))
+        return regional_values;
 
-    return return_default_hour_cycles();
+    return return_default_values();
+}
+
+// https://unicode.org/reports/tr35/tr35-dates.html#Date_Field_Symbol_Table
+Vector<Unicode::HourCycle> get_locale_hour_cycles(StringView locale)
+{
+    return find_regional_values_for_locale(locale, get_regional_hour_cycles);
 }
 
 Optional<Unicode::HourCycle> get_default_regional_hour_cycle(StringView locale)
@@ -124,6 +137,38 @@ Optional<Unicode::HourCycle> get_default_regional_hour_cycle(StringView locale)
     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);
+}
+
 String combine_skeletons(StringView first, StringView second)
 {
     // https://unicode.org/reports/tr35/tr35-dates.html#availableFormats_appendItems

Userland/Libraries/LibUnicode/DateTimeFormat.h

@@ -191,6 +191,22 @@ Vector<HourCycle> get_regional_hour_cycles(StringView region);
 Vector<Unicode::HourCycle> get_locale_hour_cycles(StringView locale);
 Optional<Unicode::HourCycle> get_default_regional_hour_cycle(StringView locale);
 
+Optional<MinimumDaysRegion> minimum_days_region_from_string(StringView minimum_days_region);
+Optional<u8> get_regional_minimum_days(StringView region);
+Optional<u8> get_locale_minimum_days(StringView region);
+
+Optional<FirstDayRegion> first_day_region_from_string(StringView first_day_region);
+Optional<Weekday> get_regional_first_day(StringView region);
+Optional<Weekday> get_locale_first_day(StringView region);
+
+Optional<WeekendStartRegion> weekend_start_region_from_string(StringView weekend_start_region);
+Optional<Weekday> get_regional_weekend_start(StringView region);
+Optional<Weekday> get_locale_weekend_start(StringView region);
+
+Optional<WeekendEndRegion> weekend_end_region_from_string(StringView weekend_end_region);
+Optional<Weekday> get_regional_weekend_end(StringView region);
+Optional<Weekday> get_locale_weekend_end(StringView region);
+
 String combine_skeletons(StringView first, StringView second);
 
 Optional<CalendarFormat> get_calendar_date_format(StringView locale, StringView calendar);

Userland/Libraries/LibUnicode/Forward.h

@@ -21,6 +21,7 @@ enum class Currency : u16;
 enum class DateField : u8;
 enum class DayPeriod : u8;
 enum class Era : u8;
+enum class FirstDayRegion : u8;
 enum class GeneralCategory : u8;
 enum class GraphemeBreakProperty : u8;
 enum class HourCycle : u8;
@@ -34,6 +35,7 @@ enum class Language : u16;
 enum class ListPatternStyle : u8;
 enum class ListPatternType : u8;
 enum class Locale : u16;
+enum class MinimumDaysRegion : u8;
 enum class Month : u8;
 enum class NumericSymbol : u8;
 enum class Property : u8;
@@ -44,6 +46,8 @@ enum class StandardNumberFormatType : u8;
 enum class Style : u8;
 enum class Territory : u8;
 enum class Weekday : u8;
+enum class WeekendEndRegion : u8;
+enum class WeekendStartRegion : u8;
 enum class WordBreakProperty : u8;
 
 struct CalendarFormat;