/*
 * Copyright (c) 2021-2025, Tim Flynn <trflynn89@ladybird.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#pragma once

#include <AK/Array.h>
#include <AK/Optional.h>
#include <AK/String.h>
#include <AK/Vector.h>
#include <LibGC/Ptr.h>
#include <LibJS/Runtime/Completion.h>
#include <LibJS/Runtime/Object.h>
#include <LibJS/Runtime/Value.h>
#include <LibUnicode/Locale.h>

namespace JS::Intl {

class Locale final : public Object {
    JS_OBJECT(Locale, Object);
    GC_DECLARE_ALLOCATOR(Locale);

public:
    static GC::Ref<Locale> create(Realm&, GC::Ref<Locale> source_locale, String);

    static constexpr auto locale_extension_keys()
    {
        // 15.2.2 Internal slots, https://tc39.es/ecma402/#sec-intl.locale-internal-slots
        // 1.3.2 Internal slots, https://tc39.es/proposal-intl-locale-info/#sec-intl.locale-internal-slots
        // The value of the [[LocaleExtensionKeys]] internal slot is a List that must include all elements of
        // « "ca", "co", "fw"sv, "hc", "nu" », must additionally include any element of « "kf", "kn" » that is also an
        // element of %Intl.Collator%.[[RelevantExtensionKeys]], and must not include any other elements.
        return AK::Array { "ca"sv, "co"sv, "fw"sv, "hc"sv, "kf"sv, "kn"sv, "nu"sv };
    }

    virtual ~Locale() override = default;

    Unicode::LocaleID const& locale_id() const;

    String const& locale() const { return m_locale; }
    void set_locale(String locale) { m_locale = move(locale); }

    bool has_calendar() const { return m_calendar.has_value(); }
    String const& calendar() const { return m_calendar.value(); }
    void set_calendar(String calendar) { m_calendar = move(calendar); }

    bool has_case_first() const { return m_case_first.has_value(); }
    String const& case_first() const { return m_case_first.value(); }
    void set_case_first(String case_first) { m_case_first = move(case_first); }

    bool has_collation() const { return m_collation.has_value(); }
    String const& collation() const { return m_collation.value(); }
    void set_collation(String collation) { m_collation = move(collation); }

    bool has_first_day_of_week() const { return m_first_day_of_week.has_value(); }
    String const& first_day_of_week() const { return m_first_day_of_week.value(); }
    void set_first_day_of_week(String first_day_of_week) { m_first_day_of_week = move(first_day_of_week); }

    bool has_hour_cycle() const { return m_hour_cycle.has_value(); }
    String const& hour_cycle() const { return m_hour_cycle.value(); }
    void set_hour_cycle(String hour_cycle) { m_hour_cycle = move(hour_cycle); }

    bool has_numbering_system() const { return m_numbering_system.has_value(); }
    String const& numbering_system() const { return m_numbering_system.value(); }
    void set_numbering_system(String numbering_system) { m_numbering_system = move(numbering_system); }

    bool numeric() const { return m_numeric; }
    void set_numeric(bool numeric) { m_numeric = numeric; }

private:
    explicit Locale(Object& prototype);

    String m_locale;                      // [[Locale]]
    Optional<String> m_calendar;          // [[Calendar]]
    Optional<String> m_case_first;        // [[CaseFirst]]
    Optional<String> m_collation;         // [[Collation]]
    Optional<String> m_first_day_of_week; // [[FirstDayOfWeek]]
    Optional<String> m_hour_cycle;        // [[HourCycle]]
    Optional<String> m_numbering_system;  // [[NumberingSystem]]
    bool m_numeric { false };             // [[Numeric]]

    mutable Optional<Unicode::LocaleID> m_cached_locale_id;
};

// Table 1: WeekInfo Record Fields, https://tc39.es/proposal-intl-locale-info/#table-locale-weekinfo-record
struct WeekInfo {
    u8 minimal_days { 0 }; // [[MinimalDays]]
    u8 first_day { 0 };    // [[FirstDay]]
    Vector<u8> weekend;    // [[Weekend]]
};

Optional<String> get_locale_variants(Unicode::LocaleID const&);

GC::Ref<Array> calendars_of_locale(VM&, Locale const&);
GC::Ref<Array> collations_of_locale(VM&, Locale const& locale);
GC::Ref<Array> hour_cycles_of_locale(VM&, Locale const& locale);
GC::Ref<Array> numbering_systems_of_locale(VM&, Locale const&);
GC::Ref<Array> time_zones_of_locale(VM&, Locale const&);
StringView weekday_to_string(StringView weekday);
Optional<u8> string_to_weekday_value(StringView weekday);
WeekInfo week_info_of_locale(Locale const&);

}
