#include <AK/String.h>
#include <AK/TypeCasts.h>
#include <LibGC/Heap.h>
#include <LibJS/Runtime/AbstractOperations.h>
#include <LibJS/Runtime/Array.h>
#include <LibJS/Runtime/Error.h>
#include <LibJS/Runtime/FunctionObject.h>
#include <LibJS/Runtime/Object.h>
#include <LibJS/Runtime/Promise.h>
#include <LibJS/Runtime/PromiseConstructor.h>
#include <LibJS/Runtime/VM.h>
#include <LibJS/Runtime/Value.h>
#include <LibJS/Runtime/ValueInlines.h>
#include <LibWeb/Bindings/EventTarget.h>
#include <LibWeb/Bindings/ExceptionOrUtils.h>
#include <LibWeb/Bindings/Intrinsics.h>
#include <LibWeb/Bindings/Navigation.h>
#include <LibWeb/HTML/Navigation.h>
#include <LibWeb/HTML/NavigationHistoryEntry.h>
#include <LibWeb/HTML/NavigationTransition.h>
#include <LibWeb/HTML/Scripting/Environments.h>
#include <LibWeb/WebIDL/AbstractOperations.h>
#include <LibWeb/WebIDL/CallbackType.h>
#include <LibWeb/WebIDL/Promise.h>
#include <LibWeb/WebIDL/Tracing.h>

namespace Web::Bindings {

void NavigationConstructor::initialize(JS::Realm& realm, JS::NativeFunction& object)
{
    auto& vm = realm.vm();
    [[maybe_unused]] u8 default_attributes = JS::Attribute::Enumerable;

    object.set_prototype(&ensure_web_constructor<EventTargetPrototype>(realm, "EventTarget"_fly_string));
    object.define_direct_property(vm.names.length, JS::Value(0), JS::Attribute::Configurable);
    object.define_direct_property(vm.names.name, JS::PrimitiveString::create(vm, "Navigation"_utf16), JS::Attribute::Configurable);
    object.define_direct_property(vm.names.prototype, &ensure_web_prototype<NavigationPrototype>(realm, "Navigation"_fly_string), 0);
}

JS::ThrowCompletionOr<GC::Ref<JS::Object>> NavigationConstructor::construct([[maybe_unused]] InterfaceConstructor& constructor, [[maybe_unused]] JS::FunctionObject& new_target)
{
    WebIDL::log_trace(constructor.vm(), "NavigationConstructor::construct");
    return constructor.vm().throw_completion<JS::TypeError>(JS::ErrorType::NotAConstructor, "Navigation");
}

void NavigationPrototype::initialize(JS::Realm& realm, JS::Object& object)
{
    [[maybe_unused]] auto& vm = realm.vm();
    [[maybe_unused]] u8 default_attributes = JS::Attribute::Enumerable | JS::Attribute::Configurable | JS::Attribute::Writable;

    object.set_prototype(GC::Ref { ensure_web_prototype<EventTargetPrototype>(realm, "EventTarget"_fly_string) });

    auto current_entry_id = "currentEntry"_utf16_fly_string;
    auto native_current_entry_getter = JS::NativeFunction::create(realm, current_entry_getter, 0, current_entry_id, &realm, "get"sv);
    GC::Ptr<JS::NativeFunction> native_current_entry_setter;

    // 4. Let configurable be false if attr is unforgeable and true otherwise.
    auto current_entry_attributes = default_attributes;

    // 5. Let desc be the PropertyDescriptor{[[Get]]: getter, [[Set]]: setter, [[Enumerable]]: true, [[Configurable]]: configurable}.

    // 7. Perform ! DefinePropertyOrThrow(target, id, desc).
    object.define_direct_accessor(current_entry_id, native_current_entry_getter, native_current_entry_setter, current_entry_attributes);

    // 8. FIXME: If attr’s type is an observable array type with type argument T, then set target’s backing observable array exotic object for attr to the result of creating an observable array exotic object in realm, given T, attr’s set an indexed value algorithm, and attr’s delete an indexed value algorithm.
    auto transition_id = "transition"_utf16_fly_string;
    auto native_transition_getter = JS::NativeFunction::create(realm, transition_getter, 0, transition_id, &realm, "get"sv);
    GC::Ptr<JS::NativeFunction> native_transition_setter;

    // 4. Let configurable be false if attr is unforgeable and true otherwise.
    auto transition_attributes = default_attributes;

    // 5. Let desc be the PropertyDescriptor{[[Get]]: getter, [[Set]]: setter, [[Enumerable]]: true, [[Configurable]]: configurable}.

    // 7. Perform ! DefinePropertyOrThrow(target, id, desc).
    object.define_direct_accessor(transition_id, native_transition_getter, native_transition_setter, transition_attributes);

    // 8. FIXME: If attr’s type is an observable array type with type argument T, then set target’s backing observable array exotic object for attr to the result of creating an observable array exotic object in realm, given T, attr’s set an indexed value algorithm, and attr’s delete an indexed value algorithm.
    auto can_go_back_id = "canGoBack"_utf16_fly_string;
    auto native_can_go_back_getter = JS::NativeFunction::create(realm, can_go_back_getter, 0, can_go_back_id, &realm, "get"sv);
    GC::Ptr<JS::NativeFunction> native_can_go_back_setter;

    // 4. Let configurable be false if attr is unforgeable and true otherwise.
    auto can_go_back_attributes = default_attributes;

    // 5. Let desc be the PropertyDescriptor{[[Get]]: getter, [[Set]]: setter, [[Enumerable]]: true, [[Configurable]]: configurable}.

    // 7. Perform ! DefinePropertyOrThrow(target, id, desc).
    object.define_direct_accessor(can_go_back_id, native_can_go_back_getter, native_can_go_back_setter, can_go_back_attributes);

    // 8. FIXME: If attr’s type is an observable array type with type argument T, then set target’s backing observable array exotic object for attr to the result of creating an observable array exotic object in realm, given T, attr’s set an indexed value algorithm, and attr’s delete an indexed value algorithm.
    auto can_go_forward_id = "canGoForward"_utf16_fly_string;
    auto native_can_go_forward_getter = JS::NativeFunction::create(realm, can_go_forward_getter, 0, can_go_forward_id, &realm, "get"sv);
    GC::Ptr<JS::NativeFunction> native_can_go_forward_setter;

    // 4. Let configurable be false if attr is unforgeable and true otherwise.
    auto can_go_forward_attributes = default_attributes;

    // 5. Let desc be the PropertyDescriptor{[[Get]]: getter, [[Set]]: setter, [[Enumerable]]: true, [[Configurable]]: configurable}.

    // 7. Perform ! DefinePropertyOrThrow(target, id, desc).
    object.define_direct_accessor(can_go_forward_id, native_can_go_forward_getter, native_can_go_forward_setter, can_go_forward_attributes);

    // 8. FIXME: If attr’s type is an observable array type with type argument T, then set target’s backing observable array exotic object for attr to the result of creating an observable array exotic object in realm, given T, attr’s set an indexed value algorithm, and attr’s delete an indexed value algorithm.
    auto onnavigate_id = "onnavigate"_utf16_fly_string;
    auto native_onnavigate_getter = JS::NativeFunction::create(realm, onnavigate_getter, 0, onnavigate_id, &realm, "get"sv);
    auto native_onnavigate_setter = JS::NativeFunction::create(realm, onnavigate_setter, 1, onnavigate_id, &realm, "set"sv);

    // 4. Let configurable be false if attr is unforgeable and true otherwise.
    auto onnavigate_attributes = default_attributes;

    // 5. Let desc be the PropertyDescriptor{[[Get]]: getter, [[Set]]: setter, [[Enumerable]]: true, [[Configurable]]: configurable}.

    // 7. Perform ! DefinePropertyOrThrow(target, id, desc).
    object.define_direct_accessor(onnavigate_id, native_onnavigate_getter, native_onnavigate_setter, onnavigate_attributes);

    // 8. FIXME: If attr’s type is an observable array type with type argument T, then set target’s backing observable array exotic object for attr to the result of creating an observable array exotic object in realm, given T, attr’s set an indexed value algorithm, and attr’s delete an indexed value algorithm.
    auto onnavigatesuccess_id = "onnavigatesuccess"_utf16_fly_string;
    auto native_onnavigatesuccess_getter = JS::NativeFunction::create(realm, onnavigatesuccess_getter, 0, onnavigatesuccess_id, &realm, "get"sv);
    auto native_onnavigatesuccess_setter = JS::NativeFunction::create(realm, onnavigatesuccess_setter, 1, onnavigatesuccess_id, &realm, "set"sv);

    // 4. Let configurable be false if attr is unforgeable and true otherwise.
    auto onnavigatesuccess_attributes = default_attributes;

    // 5. Let desc be the PropertyDescriptor{[[Get]]: getter, [[Set]]: setter, [[Enumerable]]: true, [[Configurable]]: configurable}.

    // 7. Perform ! DefinePropertyOrThrow(target, id, desc).
    object.define_direct_accessor(onnavigatesuccess_id, native_onnavigatesuccess_getter, native_onnavigatesuccess_setter, onnavigatesuccess_attributes);

    // 8. FIXME: If attr’s type is an observable array type with type argument T, then set target’s backing observable array exotic object for attr to the result of creating an observable array exotic object in realm, given T, attr’s set an indexed value algorithm, and attr’s delete an indexed value algorithm.
    auto onnavigateerror_id = "onnavigateerror"_utf16_fly_string;
    auto native_onnavigateerror_getter = JS::NativeFunction::create(realm, onnavigateerror_getter, 0, onnavigateerror_id, &realm, "get"sv);
    auto native_onnavigateerror_setter = JS::NativeFunction::create(realm, onnavigateerror_setter, 1, onnavigateerror_id, &realm, "set"sv);

    // 4. Let configurable be false if attr is unforgeable and true otherwise.
    auto onnavigateerror_attributes = default_attributes;

    // 5. Let desc be the PropertyDescriptor{[[Get]]: getter, [[Set]]: setter, [[Enumerable]]: true, [[Configurable]]: configurable}.

    // 7. Perform ! DefinePropertyOrThrow(target, id, desc).
    object.define_direct_accessor(onnavigateerror_id, native_onnavigateerror_getter, native_onnavigateerror_setter, onnavigateerror_attributes);

    // 8. FIXME: If attr’s type is an observable array type with type argument T, then set target’s backing observable array exotic object for attr to the result of creating an observable array exotic object in realm, given T, attr’s set an indexed value algorithm, and attr’s delete an indexed value algorithm.
    auto oncurrententrychange_id = "oncurrententrychange"_utf16_fly_string;
    auto native_oncurrententrychange_getter = JS::NativeFunction::create(realm, oncurrententrychange_getter, 0, oncurrententrychange_id, &realm, "get"sv);
    auto native_oncurrententrychange_setter = JS::NativeFunction::create(realm, oncurrententrychange_setter, 1, oncurrententrychange_id, &realm, "set"sv);

    // 4. Let configurable be false if attr is unforgeable and true otherwise.
    auto oncurrententrychange_attributes = default_attributes;

    // 5. Let desc be the PropertyDescriptor{[[Get]]: getter, [[Set]]: setter, [[Enumerable]]: true, [[Configurable]]: configurable}.

    // 7. Perform ! DefinePropertyOrThrow(target, id, desc).
    object.define_direct_accessor(oncurrententrychange_id, native_oncurrententrychange_getter, native_oncurrententrychange_setter, oncurrententrychange_attributes);

    // 8. FIXME: If attr’s type is an observable array type with type argument T, then set target’s backing observable array exotic object for attr to the result of creating an observable array exotic object in realm, given T, attr’s set an indexed value algorithm, and attr’s delete an indexed value algorithm.
    object.define_native_function(realm, "entries"_utf16_fly_string, entries, 0, default_attributes);

    object.define_native_function(realm, "updateCurrentEntry"_utf16_fly_string, update_current_entry, 1, default_attributes);

    object.define_native_function(realm, "navigate"_utf16_fly_string, navigate, 1, default_attributes);

    object.define_native_function(realm, "reload"_utf16_fly_string, reload, 0, default_attributes);

    object.define_native_function(realm, "traverseTo"_utf16_fly_string, traverse_to, 1, default_attributes);

    object.define_native_function(realm, "back"_utf16_fly_string, back, 0, default_attributes);

    object.define_native_function(realm, "forward"_utf16_fly_string, forward, 0, default_attributes);

    object.define_direct_property(vm.well_known_symbol_to_string_tag(), JS::PrimitiveString::create(vm, "Navigation"_utf16), JS::Attribute::Configurable);
}

void NavigationPrototype::define_unforgeable_attributes(JS::Realm& realm, [[maybe_unused]] JS::Object& object)
{
    [[maybe_unused]] auto& vm = realm.vm();
    [[maybe_unused]] u8 default_attributes = JS::Attribute::Enumerable;
}

[[maybe_unused]] static JS::ThrowCompletionOr<HTML::Navigation*> impl_from(JS::VM& vm, JS::Value js_value)
{

    if (auto impl = js_value.as_if<HTML::Navigation>())
        return impl.ptr();
    return vm.throw_completion<JS::TypeError>(JS::ErrorType::NotAnObjectOfType, "Navigation");
}

[[maybe_unused]] static JS::ThrowCompletionOr<HTML::Navigation*> impl_from(JS::VM& vm)
{
    auto this_value = vm.this_value();
    if (this_value.is_nullish())
        this_value = &vm.current_realm()->global_object();
    return impl_from(vm, this_value);
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::current_entry_getter)
{
    WebIDL::log_trace(vm, "NavigationPrototype::current_entry_getter");
    [[maybe_unused]] auto& realm = *vm.current_realm();

    auto* idl_object = TRY(impl_from(vm));


    auto R = TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->current_entry(); }));

    return [&]() -> JS::Value {
        // 1. If the IDL nullable type T? value is null, then the JavaScript value is null.
        if (!R)
            return JS::js_null();

        // 2. Otherwise, the JavaScript value is the result of converting the IDL nullable type value to the inner IDL type T.
        return JS::Value(JS::Value(R));
    }();
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::transition_getter)
{
    WebIDL::log_trace(vm, "NavigationPrototype::transition_getter");
    [[maybe_unused]] auto& realm = *vm.current_realm();

    auto* idl_object = TRY(impl_from(vm));


    auto R = TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->transition(); }));

    return [&]() -> JS::Value {
        // 1. If the IDL nullable type T? value is null, then the JavaScript value is null.
        if (!R)
            return JS::js_null();

        // 2. Otherwise, the JavaScript value is the result of converting the IDL nullable type value to the inner IDL type T.
        return JS::Value(JS::Value(R));
    }();
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::can_go_back_getter)
{
    WebIDL::log_trace(vm, "NavigationPrototype::can_go_back_getter");
    [[maybe_unused]] auto& realm = *vm.current_realm();

    auto* idl_object = TRY(impl_from(vm));


    auto R = TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->can_go_back(); }));

    return JS::Value(R);
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::can_go_forward_getter)
{
    WebIDL::log_trace(vm, "NavigationPrototype::can_go_forward_getter");
    [[maybe_unused]] auto& realm = *vm.current_realm();

    auto* idl_object = TRY(impl_from(vm));


    auto R = TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->can_go_forward(); }));

    return JS::Value(R);
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::onnavigate_getter)
{
    WebIDL::log_trace(vm, "NavigationPrototype::onnavigate_getter");
    [[maybe_unused]] auto& realm = *vm.current_realm();

    auto* idl_object = TRY(impl_from(vm));


    auto R = TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->onnavigate(); }));

    return [&]() -> JS::Value {
        // 1. If the IDL nullable type T? value is null, then the JavaScript value is null.
        if (!R)
            return JS::js_null();

        // 2. Otherwise, the JavaScript value is the result of converting the IDL nullable type value to the inner IDL type T.
        return JS::Value(R->callback);
    }();
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::onnavigatesuccess_getter)
{
    WebIDL::log_trace(vm, "NavigationPrototype::onnavigatesuccess_getter");
    [[maybe_unused]] auto& realm = *vm.current_realm();

    auto* idl_object = TRY(impl_from(vm));


    auto R = TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->onnavigatesuccess(); }));

    return [&]() -> JS::Value {
        // 1. If the IDL nullable type T? value is null, then the JavaScript value is null.
        if (!R)
            return JS::js_null();

        // 2. Otherwise, the JavaScript value is the result of converting the IDL nullable type value to the inner IDL type T.
        return JS::Value(R->callback);
    }();
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::onnavigateerror_getter)
{
    WebIDL::log_trace(vm, "NavigationPrototype::onnavigateerror_getter");
    [[maybe_unused]] auto& realm = *vm.current_realm();

    auto* idl_object = TRY(impl_from(vm));


    auto R = TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->onnavigateerror(); }));

    return [&]() -> JS::Value {
        // 1. If the IDL nullable type T? value is null, then the JavaScript value is null.
        if (!R)
            return JS::js_null();

        // 2. Otherwise, the JavaScript value is the result of converting the IDL nullable type value to the inner IDL type T.
        return JS::Value(R->callback);
    }();
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::oncurrententrychange_getter)
{
    WebIDL::log_trace(vm, "NavigationPrototype::oncurrententrychange_getter");
    [[maybe_unused]] auto& realm = *vm.current_realm();

    auto* idl_object = TRY(impl_from(vm));


    auto R = TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->oncurrententrychange(); }));

    return [&]() -> JS::Value {
        // 1. If the IDL nullable type T? value is null, then the JavaScript value is null.
        if (!R)
            return JS::js_null();

        // 2. Otherwise, the JavaScript value is the result of converting the IDL nullable type value to the inner IDL type T.
        return JS::Value(R->callback);
    }();
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::onnavigate_setter)
{
    WebIDL::log_trace(vm, "NavigationPrototype::onnavigate_setter");
    [[maybe_unused]] auto& realm = *vm.current_realm();

    // 1. Let V be undefined.
    auto V = JS::js_undefined();

    // 2. If any arguments were passed, then set V to the value of the first argument passed.
    if (vm.argument_count() > 0)
        V = vm.argument(0);

    // 3. Let id be attribute’s identifier.

    // 4. Let idlObject be null.
    [[maybe_unused]] HTML::Navigation* idl_object = nullptr;

    // 5. If attribute is a regular attribute:

    // 1. Let jsValue be the this value, if it is not null or undefined, or realm’s global object otherwise. (This will subsequently cause a TypeError in a few steps, if the global object does not implement target and [LegacyLenientThis] is not specified.)
    auto js_value = vm.this_value();
    if (js_value.is_nullish())
        js_value = &realm.global_object();

    // 2. FIXME: If jsValue is a platform object, then perform a security check, passing jsValue, attribute’s identifier, and "setter".

    // 3. Let validThis be true if jsValue implements target, or false otherwise.
    auto maybe_idl_object = impl_from(vm, js_value);

    // 4. If validThis is false and attribute was not specified with the [LegacyLenientThis] extended attribute, then throw a TypeError.
    idl_object = TRY(maybe_idl_object);

    auto original_steps = [&]() -> JS::ThrowCompletionOr<JS::Value> {
        // 6. Let idlValue be determined as follows:
        // -> Otherwise, idlValue is the result of converting V to an IDL value of attribute’s type.
        auto idl_value = TRY(throw_dom_exception_if_needed(vm, [&] { return [&]() -> JS::ThrowCompletionOr<GC::Ptr<WebIDL::CallbackType>> {
        GC::Ptr<WebIDL::CallbackType> value;
        if (V.is_object()) {

        if (!V.is_nullish()) {

            value = TRY([&]() -> JS::ThrowCompletionOr<GC::Ptr<WebIDL::CallbackType>> {

        return vm.heap().allocate<WebIDL::CallbackType>(V.as_object(),  HTML::incumbent_realm(), WebIDL::OperationReturnsPromise::No);
    }());
        }
        }
        return value;
    }(); }));

        // 7. Run the setter steps of attribute with idlObject as this and idlValue as the value.
        auto setter_result = [&]() -> JS::ThrowCompletionOr<void> {
            TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->set_onnavigate(idl_value); }));
    return {};
        }();

        if (setter_result.is_error())
            return setter_result.release_error();

        return JS::js_undefined();
    };

    // 8. Return undefined.
    return TRY(original_steps());
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::onnavigatesuccess_setter)
{
    WebIDL::log_trace(vm, "NavigationPrototype::onnavigatesuccess_setter");
    [[maybe_unused]] auto& realm = *vm.current_realm();

    // 1. Let V be undefined.
    auto V = JS::js_undefined();

    // 2. If any arguments were passed, then set V to the value of the first argument passed.
    if (vm.argument_count() > 0)
        V = vm.argument(0);

    // 3. Let id be attribute’s identifier.

    // 4. Let idlObject be null.
    [[maybe_unused]] HTML::Navigation* idl_object = nullptr;

    // 5. If attribute is a regular attribute:

    // 1. Let jsValue be the this value, if it is not null or undefined, or realm’s global object otherwise. (This will subsequently cause a TypeError in a few steps, if the global object does not implement target and [LegacyLenientThis] is not specified.)
    auto js_value = vm.this_value();
    if (js_value.is_nullish())
        js_value = &realm.global_object();

    // 2. FIXME: If jsValue is a platform object, then perform a security check, passing jsValue, attribute’s identifier, and "setter".

    // 3. Let validThis be true if jsValue implements target, or false otherwise.
    auto maybe_idl_object = impl_from(vm, js_value);

    // 4. If validThis is false and attribute was not specified with the [LegacyLenientThis] extended attribute, then throw a TypeError.
    idl_object = TRY(maybe_idl_object);

    auto original_steps = [&]() -> JS::ThrowCompletionOr<JS::Value> {
        // 6. Let idlValue be determined as follows:
        // -> Otherwise, idlValue is the result of converting V to an IDL value of attribute’s type.
        auto idl_value = TRY(throw_dom_exception_if_needed(vm, [&] { return [&]() -> JS::ThrowCompletionOr<GC::Ptr<WebIDL::CallbackType>> {
        GC::Ptr<WebIDL::CallbackType> value;
        if (V.is_object()) {

        if (!V.is_nullish()) {

            value = TRY([&]() -> JS::ThrowCompletionOr<GC::Ptr<WebIDL::CallbackType>> {

        return vm.heap().allocate<WebIDL::CallbackType>(V.as_object(),  HTML::incumbent_realm(), WebIDL::OperationReturnsPromise::No);
    }());
        }
        }
        return value;
    }(); }));

        // 7. Run the setter steps of attribute with idlObject as this and idlValue as the value.
        auto setter_result = [&]() -> JS::ThrowCompletionOr<void> {
            TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->set_onnavigatesuccess(idl_value); }));
    return {};
        }();

        if (setter_result.is_error())
            return setter_result.release_error();

        return JS::js_undefined();
    };

    // 8. Return undefined.
    return TRY(original_steps());
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::onnavigateerror_setter)
{
    WebIDL::log_trace(vm, "NavigationPrototype::onnavigateerror_setter");
    [[maybe_unused]] auto& realm = *vm.current_realm();

    // 1. Let V be undefined.
    auto V = JS::js_undefined();

    // 2. If any arguments were passed, then set V to the value of the first argument passed.
    if (vm.argument_count() > 0)
        V = vm.argument(0);

    // 3. Let id be attribute’s identifier.

    // 4. Let idlObject be null.
    [[maybe_unused]] HTML::Navigation* idl_object = nullptr;

    // 5. If attribute is a regular attribute:

    // 1. Let jsValue be the this value, if it is not null or undefined, or realm’s global object otherwise. (This will subsequently cause a TypeError in a few steps, if the global object does not implement target and [LegacyLenientThis] is not specified.)
    auto js_value = vm.this_value();
    if (js_value.is_nullish())
        js_value = &realm.global_object();

    // 2. FIXME: If jsValue is a platform object, then perform a security check, passing jsValue, attribute’s identifier, and "setter".

    // 3. Let validThis be true if jsValue implements target, or false otherwise.
    auto maybe_idl_object = impl_from(vm, js_value);

    // 4. If validThis is false and attribute was not specified with the [LegacyLenientThis] extended attribute, then throw a TypeError.
    idl_object = TRY(maybe_idl_object);

    auto original_steps = [&]() -> JS::ThrowCompletionOr<JS::Value> {
        // 6. Let idlValue be determined as follows:
        // -> Otherwise, idlValue is the result of converting V to an IDL value of attribute’s type.
        auto idl_value = TRY(throw_dom_exception_if_needed(vm, [&] { return [&]() -> JS::ThrowCompletionOr<GC::Ptr<WebIDL::CallbackType>> {
        GC::Ptr<WebIDL::CallbackType> value;
        if (V.is_object()) {

        if (!V.is_nullish()) {

            value = TRY([&]() -> JS::ThrowCompletionOr<GC::Ptr<WebIDL::CallbackType>> {

        return vm.heap().allocate<WebIDL::CallbackType>(V.as_object(),  HTML::incumbent_realm(), WebIDL::OperationReturnsPromise::No);
    }());
        }
        }
        return value;
    }(); }));

        // 7. Run the setter steps of attribute with idlObject as this and idlValue as the value.
        auto setter_result = [&]() -> JS::ThrowCompletionOr<void> {
            TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->set_onnavigateerror(idl_value); }));
    return {};
        }();

        if (setter_result.is_error())
            return setter_result.release_error();

        return JS::js_undefined();
    };

    // 8. Return undefined.
    return TRY(original_steps());
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::oncurrententrychange_setter)
{
    WebIDL::log_trace(vm, "NavigationPrototype::oncurrententrychange_setter");
    [[maybe_unused]] auto& realm = *vm.current_realm();

    // 1. Let V be undefined.
    auto V = JS::js_undefined();

    // 2. If any arguments were passed, then set V to the value of the first argument passed.
    if (vm.argument_count() > 0)
        V = vm.argument(0);

    // 3. Let id be attribute’s identifier.

    // 4. Let idlObject be null.
    [[maybe_unused]] HTML::Navigation* idl_object = nullptr;

    // 5. If attribute is a regular attribute:

    // 1. Let jsValue be the this value, if it is not null or undefined, or realm’s global object otherwise. (This will subsequently cause a TypeError in a few steps, if the global object does not implement target and [LegacyLenientThis] is not specified.)
    auto js_value = vm.this_value();
    if (js_value.is_nullish())
        js_value = &realm.global_object();

    // 2. FIXME: If jsValue is a platform object, then perform a security check, passing jsValue, attribute’s identifier, and "setter".

    // 3. Let validThis be true if jsValue implements target, or false otherwise.
    auto maybe_idl_object = impl_from(vm, js_value);

    // 4. If validThis is false and attribute was not specified with the [LegacyLenientThis] extended attribute, then throw a TypeError.
    idl_object = TRY(maybe_idl_object);

    auto original_steps = [&]() -> JS::ThrowCompletionOr<JS::Value> {
        // 6. Let idlValue be determined as follows:
        // -> Otherwise, idlValue is the result of converting V to an IDL value of attribute’s type.
        auto idl_value = TRY(throw_dom_exception_if_needed(vm, [&] { return [&]() -> JS::ThrowCompletionOr<GC::Ptr<WebIDL::CallbackType>> {
        GC::Ptr<WebIDL::CallbackType> value;
        if (V.is_object()) {

        if (!V.is_nullish()) {

            value = TRY([&]() -> JS::ThrowCompletionOr<GC::Ptr<WebIDL::CallbackType>> {

        return vm.heap().allocate<WebIDL::CallbackType>(V.as_object(),  HTML::incumbent_realm(), WebIDL::OperationReturnsPromise::No);
    }());
        }
        }
        return value;
    }(); }));

        // 7. Run the setter steps of attribute with idlObject as this and idlValue as the value.
        auto setter_result = [&]() -> JS::ThrowCompletionOr<void> {
            TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->set_oncurrententrychange(idl_value); }));
    return {};
        }();

        if (setter_result.is_error())
            return setter_result.release_error();

        return JS::js_undefined();
    };

    // 8. Return undefined.
    return TRY(original_steps());
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::entries)
{
    WebIDL::log_trace(vm, "NavigationPrototype::entries");
    [[maybe_unused]] auto& realm = *vm.current_realm();
    [[maybe_unused]] HTML::Navigation* idl_object = TRY(impl_from(vm));

    [[maybe_unused]] auto R = TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->entries(); }));
    return [&]() -> JS::Value {
        // An IDL sequence<T> value S is converted to a JavaScript value as follows:
        // 1. Let n be the length of S.
        auto sequence_length = R.size();

        // 2. Let A be a new Array object created as if by the expression [].
        auto sequence_array = MUST(JS::Array::create(realm, sequence_length));

        // 3. Initialize i to be 0.
        // 4. While i < n:
        for (size_t sequence_index = 0; sequence_index < sequence_length; ++sequence_index) {
            // 1. Let V be the value in S at index i.
            auto& sequence_element = R.at(sequence_index);

            // 2. Let E be the result of converting V to a JavaScript value.
            JS::Value js_sequence_element = JS::Value(sequence_element);

            // 3. Let P be the result of calling ! ToString(i).
            // 4. Perform ! CreateDataPropertyOrThrow(A, P, E).
            MUST(sequence_array->create_data_property(JS::PropertyKey { sequence_index }, js_sequence_element));

            // 5. Set i to i + 1.
        }

        // 5. Return A.
        return sequence_array;
    }();
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::update_current_entry)
{
    WebIDL::log_trace(vm, "NavigationPrototype::update_current_entry");
    [[maybe_unused]] auto& realm = *vm.current_realm();
    [[maybe_unused]] HTML::Navigation* idl_object = TRY(impl_from(vm));

    if (vm.argument_count() < 1)
        return vm.throw_completion<JS::TypeError>(JS::ErrorType::BadArgCountOne, "updateCurrentEntry");

    auto arg0 = vm.argument(0);
    auto options = TRY(throw_dom_exception_if_needed(vm, [&] { return convert_to_idl_value_for_navigation_update_current_entry_options(vm, arg0); }));

    [[maybe_unused]] auto R = TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->update_current_entry(options); }));
    return JS::js_undefined();
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::navigate)
{
    WebIDL::log_trace(vm, "NavigationPrototype::navigate");
    [[maybe_unused]] auto& realm = *vm.current_realm();
    [[maybe_unused]] HTML::Navigation* idl_object = TRY(impl_from(vm));

    if (vm.argument_count() < 1)
        return vm.throw_completion<JS::TypeError>(JS::ErrorType::BadArgCountOne, "navigate");

    auto arg0 = vm.argument(0);
    auto url = TRY(throw_dom_exception_if_needed(vm, [&] { return [&]() -> JS::ThrowCompletionOr<String> {
        return TRY(WebIDL::to_usv_string(vm, arg0));
    }(); }));

    auto arg1 = vm.argument(1);
    NavigationNavigateOptions options = NavigationNavigateOptions {};
    if (!arg1.is_undefined())
        options = TRY(throw_dom_exception_if_needed(vm, [&] { return convert_to_idl_value_for_navigation_navigate_options(vm, arg1); }));

    [[maybe_unused]] auto R = TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->navigate(url, options); }));
    return [&]() -> JS::Value {
        // 1. Let O be OrdinaryObjectCreate(%Object.prototype%).
        auto dictionary_object = JS::Object::create(realm, realm.intrinsics().object_prototype());

        // 1. Let key be the identifier of member.
        // 2. If V[key] exists, then:
        if (R.committed) {

        // 1. Let idlValue be V[key].
        // 2. Let value be the result of converting idlValue to a JavaScript value.
        // 3. Perform ! CreateDataPropertyOrThrow(O, key, value).
        MUST(dictionary_object->create_data_property("committed"_utf16_fly_string, GC::Ref { as<JS::Promise>(*R.committed->promise()) }));
        }

        // 1. Let key be the identifier of member.
        // 2. If V[key] exists, then:
        if (R.finished) {

        // 1. Let idlValue be V[key].
        // 2. Let value be the result of converting idlValue to a JavaScript value.
        // 3. Perform ! CreateDataPropertyOrThrow(O, key, value).
        MUST(dictionary_object->create_data_property("finished"_utf16_fly_string, GC::Ref { as<JS::Promise>(*R.finished->promise()) }));
        }

        // 4. Return O.
        return dictionary_object;
    }();
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::reload)
{
    WebIDL::log_trace(vm, "NavigationPrototype::reload");
    [[maybe_unused]] auto& realm = *vm.current_realm();
    [[maybe_unused]] HTML::Navigation* idl_object = TRY(impl_from(vm));

    auto arg0 = vm.argument(0);
    NavigationReloadOptions options = NavigationReloadOptions {};
    if (!arg0.is_undefined())
        options = TRY(throw_dom_exception_if_needed(vm, [&] { return convert_to_idl_value_for_navigation_reload_options(vm, arg0); }));

    [[maybe_unused]] auto R = TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->reload(options); }));
    return [&]() -> JS::Value {
        // 1. Let O be OrdinaryObjectCreate(%Object.prototype%).
        auto dictionary_object = JS::Object::create(realm, realm.intrinsics().object_prototype());

        // 1. Let key be the identifier of member.
        // 2. If V[key] exists, then:
        if (R.committed) {

        // 1. Let idlValue be V[key].
        // 2. Let value be the result of converting idlValue to a JavaScript value.
        // 3. Perform ! CreateDataPropertyOrThrow(O, key, value).
        MUST(dictionary_object->create_data_property("committed"_utf16_fly_string, GC::Ref { as<JS::Promise>(*R.committed->promise()) }));
        }

        // 1. Let key be the identifier of member.
        // 2. If V[key] exists, then:
        if (R.finished) {

        // 1. Let idlValue be V[key].
        // 2. Let value be the result of converting idlValue to a JavaScript value.
        // 3. Perform ! CreateDataPropertyOrThrow(O, key, value).
        MUST(dictionary_object->create_data_property("finished"_utf16_fly_string, GC::Ref { as<JS::Promise>(*R.finished->promise()) }));
        }

        // 4. Return O.
        return dictionary_object;
    }();
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::traverse_to)
{
    WebIDL::log_trace(vm, "NavigationPrototype::traverse_to");
    [[maybe_unused]] auto& realm = *vm.current_realm();
    [[maybe_unused]] HTML::Navigation* idl_object = TRY(impl_from(vm));

    if (vm.argument_count() < 1)
        return vm.throw_completion<JS::TypeError>(JS::ErrorType::BadArgCountOne, "traverseTo");

    auto arg0 = vm.argument(0);
    auto key = TRY(throw_dom_exception_if_needed(vm, [&] { return [&]() -> JS::ThrowCompletionOr<String> {
        return TRY(WebIDL::to_string(vm, arg0));
    }(); }));

    auto arg1 = vm.argument(1);
    NavigationOptions options = NavigationOptions {};
    if (!arg1.is_undefined())
        options = TRY(throw_dom_exception_if_needed(vm, [&] { return convert_to_idl_value_for_navigation_options(vm, arg1); }));

    [[maybe_unused]] auto R = TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->traverse_to(key, options); }));
    return [&]() -> JS::Value {
        // 1. Let O be OrdinaryObjectCreate(%Object.prototype%).
        auto dictionary_object = JS::Object::create(realm, realm.intrinsics().object_prototype());

        // 1. Let key be the identifier of member.
        // 2. If V[key] exists, then:
        if (R.committed) {

        // 1. Let idlValue be V[key].
        // 2. Let value be the result of converting idlValue to a JavaScript value.
        // 3. Perform ! CreateDataPropertyOrThrow(O, key, value).
        MUST(dictionary_object->create_data_property("committed"_utf16_fly_string, GC::Ref { as<JS::Promise>(*R.committed->promise()) }));
        }

        // 1. Let key be the identifier of member.
        // 2. If V[key] exists, then:
        if (R.finished) {

        // 1. Let idlValue be V[key].
        // 2. Let value be the result of converting idlValue to a JavaScript value.
        // 3. Perform ! CreateDataPropertyOrThrow(O, key, value).
        MUST(dictionary_object->create_data_property("finished"_utf16_fly_string, GC::Ref { as<JS::Promise>(*R.finished->promise()) }));
        }

        // 4. Return O.
        return dictionary_object;
    }();
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::back)
{
    WebIDL::log_trace(vm, "NavigationPrototype::back");
    [[maybe_unused]] auto& realm = *vm.current_realm();
    [[maybe_unused]] HTML::Navigation* idl_object = TRY(impl_from(vm));

    auto arg0 = vm.argument(0);
    NavigationOptions options = NavigationOptions {};
    if (!arg0.is_undefined())
        options = TRY(throw_dom_exception_if_needed(vm, [&] { return convert_to_idl_value_for_navigation_options(vm, arg0); }));

    [[maybe_unused]] auto R = TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->back(options); }));
    return [&]() -> JS::Value {
        // 1. Let O be OrdinaryObjectCreate(%Object.prototype%).
        auto dictionary_object = JS::Object::create(realm, realm.intrinsics().object_prototype());

        // 1. Let key be the identifier of member.
        // 2. If V[key] exists, then:
        if (R.committed) {

        // 1. Let idlValue be V[key].
        // 2. Let value be the result of converting idlValue to a JavaScript value.
        // 3. Perform ! CreateDataPropertyOrThrow(O, key, value).
        MUST(dictionary_object->create_data_property("committed"_utf16_fly_string, GC::Ref { as<JS::Promise>(*R.committed->promise()) }));
        }

        // 1. Let key be the identifier of member.
        // 2. If V[key] exists, then:
        if (R.finished) {

        // 1. Let idlValue be V[key].
        // 2. Let value be the result of converting idlValue to a JavaScript value.
        // 3. Perform ! CreateDataPropertyOrThrow(O, key, value).
        MUST(dictionary_object->create_data_property("finished"_utf16_fly_string, GC::Ref { as<JS::Promise>(*R.finished->promise()) }));
        }

        // 4. Return O.
        return dictionary_object;
    }();
}

JS_DEFINE_NATIVE_FUNCTION(NavigationPrototype::forward)
{
    WebIDL::log_trace(vm, "NavigationPrototype::forward");
    [[maybe_unused]] auto& realm = *vm.current_realm();
    [[maybe_unused]] HTML::Navigation* idl_object = TRY(impl_from(vm));

    auto arg0 = vm.argument(0);
    NavigationOptions options = NavigationOptions {};
    if (!arg0.is_undefined())
        options = TRY(throw_dom_exception_if_needed(vm, [&] { return convert_to_idl_value_for_navigation_options(vm, arg0); }));

    [[maybe_unused]] auto R = TRY(throw_dom_exception_if_needed(vm, [&] { return idl_object->forward(options); }));
    return [&]() -> JS::Value {
        // 1. Let O be OrdinaryObjectCreate(%Object.prototype%).
        auto dictionary_object = JS::Object::create(realm, realm.intrinsics().object_prototype());

        // 1. Let key be the identifier of member.
        // 2. If V[key] exists, then:
        if (R.committed) {

        // 1. Let idlValue be V[key].
        // 2. Let value be the result of converting idlValue to a JavaScript value.
        // 3. Perform ! CreateDataPropertyOrThrow(O, key, value).
        MUST(dictionary_object->create_data_property("committed"_utf16_fly_string, GC::Ref { as<JS::Promise>(*R.committed->promise()) }));
        }

        // 1. Let key be the identifier of member.
        // 2. If V[key] exists, then:
        if (R.finished) {

        // 1. Let idlValue be V[key].
        // 2. Let value be the result of converting idlValue to a JavaScript value.
        // 3. Perform ! CreateDataPropertyOrThrow(O, key, value).
        MUST(dictionary_object->create_data_property("finished"_utf16_fly_string, GC::Ref { as<JS::Promise>(*R.finished->promise()) }));
        }

        // 4. Return O.
        return dictionary_object;
    }();
}

// https://webidl.spec.whatwg.org/#idl-enumeration
JS::ThrowCompletionOr<NavigationHistoryBehavior> convert_to_idl_value_for_navigation_history_behavior(JS::VM& vm, JS::Value value)
{
    // 1. Let S be the result of calling ? ToString(V).
    auto value_as_string = TRY(value.to_utf16_string(vm));

    // 2. If S is not one of E’s enumeration values, then throw a TypeError.
    // 3. Return the enumeration value of type E that is equal to S.
    if (value_as_string == "auto"sv)
        return NavigationHistoryBehavior::Auto;
    if (value_as_string == "push"sv)
        return NavigationHistoryBehavior::Push;
    if (value_as_string == "replace"sv)
        return NavigationHistoryBehavior::Replace;
    return vm.throw_completion<JS::TypeError>(JS::ErrorType::InvalidEnumerationValue, value_as_string, "NavigationHistoryBehavior");
}

// https://webidl.spec.whatwg.org/#idl-enumeration
Utf16String idl_enum_to_string(NavigationHistoryBehavior value)
{
    // The result of converting an IDL enumeration type value to a JavaScript value is the String value that represents the same sequence of code units as the enumeration value.
    switch (value) {
    case NavigationHistoryBehavior::Auto:
        return "auto"_utf16;
    case NavigationHistoryBehavior::Push:
        return "push"_utf16;
    case NavigationHistoryBehavior::Replace:
        return "replace"_utf16;
    }
    VERIFY_NOT_REACHED();
}

// https://webidl.spec.whatwg.org/#es-dictionary
JS::ThrowCompletionOr<NavigationUpdateCurrentEntryOptions> convert_to_idl_value_for_navigation_update_current_entry_options(JS::VM& vm, JS::Value js_dict)
{
    // 1. If jsDict is not an Object and jsDict is neither undefined nor null, then throw a TypeError.
    if (!js_dict.is_object() && !js_dict.is_nullish())
        return vm.throw_completion<JS::TypeError>(JS::ErrorType::NotAnObjectOfType, "NavigationUpdateCurrentEntryOptions");

    // 2. Let idlDict be an empty ordered map, representing a dictionary of type D.
    // 3. Let dictionaries be a list consisting of D and all of D’s inherited dictionaries, in order from least to most derived.
    // 4. For each dictionary dictionary in dictionaries, in order:
    // NB: We defer construction until the return initializer because some members may not be default-constructible. Inherited dictionaries are represented by the generated C++ struct inheritance.

    // 5. Return idlDict.
    return NavigationUpdateCurrentEntryOptions {
        .state = TRY([&]() -> JS::ThrowCompletionOr<JS::Value> {
            // 1. Let key be the identifier of member.
            // 2. If jsDict is either undefined or null, then:
            //     1. Let jsMemberValue be undefined.
            // 3. Otherwise,
            //     1. Let jsMemberValue be ? Get(jsDict, key).
            auto js_member_value = JS::js_undefined();
            if (js_dict.is_object())
                js_member_value = TRY(js_dict.as_object().get("state"_utf16_fly_string));

            // 4. If jsMemberValue is not undefined, then:
            if (!js_member_value.is_undefined()) {
                // 1. Let idlMemberValue be the result of converting jsMemberValue to an IDL value whose type is the type member is declared to be of.
                auto idl_member_value = TRY(throw_dom_exception_if_needed(vm, [&] { return js_member_value; }));

                // 2. Set idlDict[key] to idlMemberValue.
                return idl_member_value;
            }
            // 6. Otherwise, if jsMemberValue is undefined and member is required, then throw a TypeError.
            return vm.throw_completion<JS::TypeError>(JS::ErrorType::MissingRequiredProperty, "state");
        }()),
    };
}

// https://webidl.spec.whatwg.org/#es-dictionary
JS::ThrowCompletionOr<NavigationOptions> convert_to_idl_value_for_navigation_options(JS::VM& vm, JS::Value js_dict)
{
    // 1. If jsDict is not an Object and jsDict is neither undefined nor null, then throw a TypeError.
    if (!js_dict.is_object() && !js_dict.is_nullish())
        return vm.throw_completion<JS::TypeError>(JS::ErrorType::NotAnObjectOfType, "NavigationOptions");

    // 2. Let idlDict be an empty ordered map, representing a dictionary of type D.
    // 3. Let dictionaries be a list consisting of D and all of D’s inherited dictionaries, in order from least to most derived.
    // 4. For each dictionary dictionary in dictionaries, in order:
    // NB: We defer construction until the return initializer because some members may not be default-constructible. Inherited dictionaries are represented by the generated C++ struct inheritance.

    // 5. Return idlDict.
    return NavigationOptions {
        .info = TRY([&]() -> JS::ThrowCompletionOr<Optional<JS::Value>> {
            // 1. Let key be the identifier of member.
            // 2. If jsDict is either undefined or null, then:
            //     1. Let jsMemberValue be undefined.
            // 3. Otherwise,
            //     1. Let jsMemberValue be ? Get(jsDict, key).
            auto js_member_value = JS::js_undefined();
            if (js_dict.is_object())
                js_member_value = TRY(js_dict.as_object().get("info"_utf16_fly_string));

            // 4. If jsMemberValue is not undefined, then:
            if (!js_member_value.is_undefined()) {
                // 1. Let idlMemberValue be the result of converting jsMemberValue to an IDL value whose type is the type member is declared to be of.
                auto idl_member_value = TRY(throw_dom_exception_if_needed(vm, [&] { return js_member_value; }));

                // 2. Set idlDict[key] to idlMemberValue.
                return idl_member_value;
            }
            // 7. Otherwise, jsMemberValue is undefined and the member is optional.
            return OptionalNone {};
        }()),
    };
}

// https://webidl.spec.whatwg.org/#es-dictionary
JS::ThrowCompletionOr<NavigationNavigateOptions> convert_to_idl_value_for_navigation_navigate_options(JS::VM& vm, JS::Value js_dict)
{
    // 1. If jsDict is not an Object and jsDict is neither undefined nor null, then throw a TypeError.
    if (!js_dict.is_object() && !js_dict.is_nullish())
        return vm.throw_completion<JS::TypeError>(JS::ErrorType::NotAnObjectOfType, "NavigationNavigateOptions");

    // 2. Let idlDict be an empty ordered map, representing a dictionary of type D.
    // 3. Let dictionaries be a list consisting of D and all of D’s inherited dictionaries, in order from least to most derived.
    // 4. For each dictionary dictionary in dictionaries, in order:
    // NB: We defer construction until the return initializer because some members may not be default-constructible. Inherited dictionaries are represented by the generated C++ struct inheritance.

    // 5. Return idlDict.
    return NavigationNavigateOptions {
        TRY(convert_to_idl_value_for_navigation_options(vm, js_dict)),
        TRY([&]() -> JS::ThrowCompletionOr<NavigationHistoryBehavior> {
            // 1. Let key be the identifier of member.
            // 2. If jsDict is either undefined or null, then:
            //     1. Let jsMemberValue be undefined.
            // 3. Otherwise,
            //     1. Let jsMemberValue be ? Get(jsDict, key).
            auto js_member_value = JS::js_undefined();
            if (js_dict.is_object())
                js_member_value = TRY(js_dict.as_object().get("history"_utf16_fly_string));

            // 4. If jsMemberValue is not undefined, then:
            if (!js_member_value.is_undefined()) {
                // 1. Let idlMemberValue be the result of converting jsMemberValue to an IDL value whose type is the type member is declared to be of.
                auto idl_member_value = TRY(throw_dom_exception_if_needed(vm, [&] { return convert_to_idl_value_for_navigation_history_behavior(vm, js_member_value); }));

                // 2. Set idlDict[key] to idlMemberValue.
                return idl_member_value;
            }
            // 5. Otherwise, if jsMemberValue is undefined but member has a default value, then:
            // 1. Let idlMemberValue be the result of converting member's default value to an IDL value whose type is the type member is declared to be of.
            auto idl_member_value = NavigationHistoryBehavior::Auto;

            // 2. Set idlDict[key] to idlMemberValue.
            return idl_member_value;
        }()),
        TRY([&]() -> JS::ThrowCompletionOr<Optional<JS::Value>> {
            // 1. Let key be the identifier of member.
            // 2. If jsDict is either undefined or null, then:
            //     1. Let jsMemberValue be undefined.
            // 3. Otherwise,
            //     1. Let jsMemberValue be ? Get(jsDict, key).
            auto js_member_value = JS::js_undefined();
            if (js_dict.is_object())
                js_member_value = TRY(js_dict.as_object().get("state"_utf16_fly_string));

            // 4. If jsMemberValue is not undefined, then:
            if (!js_member_value.is_undefined()) {
                // 1. Let idlMemberValue be the result of converting jsMemberValue to an IDL value whose type is the type member is declared to be of.
                auto idl_member_value = TRY(throw_dom_exception_if_needed(vm, [&] { return js_member_value; }));

                // 2. Set idlDict[key] to idlMemberValue.
                return idl_member_value;
            }
            // 7. Otherwise, jsMemberValue is undefined and the member is optional.
            return OptionalNone {};
        }()),
    };
}

// https://webidl.spec.whatwg.org/#es-dictionary
JS::ThrowCompletionOr<NavigationReloadOptions> convert_to_idl_value_for_navigation_reload_options(JS::VM& vm, JS::Value js_dict)
{
    // 1. If jsDict is not an Object and jsDict is neither undefined nor null, then throw a TypeError.
    if (!js_dict.is_object() && !js_dict.is_nullish())
        return vm.throw_completion<JS::TypeError>(JS::ErrorType::NotAnObjectOfType, "NavigationReloadOptions");

    // 2. Let idlDict be an empty ordered map, representing a dictionary of type D.
    // 3. Let dictionaries be a list consisting of D and all of D’s inherited dictionaries, in order from least to most derived.
    // 4. For each dictionary dictionary in dictionaries, in order:
    // NB: We defer construction until the return initializer because some members may not be default-constructible. Inherited dictionaries are represented by the generated C++ struct inheritance.

    // 5. Return idlDict.
    return NavigationReloadOptions {
        TRY(convert_to_idl_value_for_navigation_options(vm, js_dict)),
        TRY([&]() -> JS::ThrowCompletionOr<Optional<JS::Value>> {
            // 1. Let key be the identifier of member.
            // 2. If jsDict is either undefined or null, then:
            //     1. Let jsMemberValue be undefined.
            // 3. Otherwise,
            //     1. Let jsMemberValue be ? Get(jsDict, key).
            auto js_member_value = JS::js_undefined();
            if (js_dict.is_object())
                js_member_value = TRY(js_dict.as_object().get("state"_utf16_fly_string));

            // 4. If jsMemberValue is not undefined, then:
            if (!js_member_value.is_undefined()) {
                // 1. Let idlMemberValue be the result of converting jsMemberValue to an IDL value whose type is the type member is declared to be of.
                auto idl_member_value = TRY(throw_dom_exception_if_needed(vm, [&] { return js_member_value; }));

                // 2. Set idlDict[key] to idlMemberValue.
                return idl_member_value;
            }
            // 7. Otherwise, jsMemberValue is undefined and the member is optional.
            return OptionalNone {};
        }()),
    };
}

// https://webidl.spec.whatwg.org/#es-dictionary
JS::ThrowCompletionOr<NavigationResult> convert_to_idl_value_for_navigation_result(JS::VM& vm, JS::Value js_dict)
{
    // 1. If jsDict is not an Object and jsDict is neither undefined nor null, then throw a TypeError.
    if (!js_dict.is_object() && !js_dict.is_nullish())
        return vm.throw_completion<JS::TypeError>(JS::ErrorType::NotAnObjectOfType, "NavigationResult");

    // 2. Let idlDict be an empty ordered map, representing a dictionary of type D.
    // 3. Let dictionaries be a list consisting of D and all of D’s inherited dictionaries, in order from least to most derived.
    // 4. For each dictionary dictionary in dictionaries, in order:
    // NB: We defer construction until the return initializer because some members may not be default-constructible. Inherited dictionaries are represented by the generated C++ struct inheritance.

    // 5. Return idlDict.
    return NavigationResult {
        .committed = TRY([&]() -> JS::ThrowCompletionOr<GC::Ptr<WebIDL::Promise>> {
            // 1. Let key be the identifier of member.
            // 2. If jsDict is either undefined or null, then:
            //     1. Let jsMemberValue be undefined.
            // 3. Otherwise,
            //     1. Let jsMemberValue be ? Get(jsDict, key).
            auto js_member_value = JS::js_undefined();
            if (js_dict.is_object())
                js_member_value = TRY(js_dict.as_object().get("committed"_utf16_fly_string));

            // 4. If jsMemberValue is not undefined, then:
            if (!js_member_value.is_undefined()) {
                // 1. Let idlMemberValue be the result of converting jsMemberValue to an IDL value whose type is the type member is declared to be of.
                auto idl_member_value = TRY(throw_dom_exception_if_needed(vm, [&] { return [&]() -> JS::ThrowCompletionOr<GC::Ref<WebIDL::Promise>> {
        auto& realm = *vm.current_realm();

        // 1. Let promiseCapability be ? NewPromiseCapability(%Promise%).
        auto promise_capability0 = TRY(JS::new_promise_capability(vm, realm.intrinsics().promise_constructor()));

        // 2. Perform ? Call(promiseCapability.[[Resolve]], undefined, « V »).
        TRY(JS::call(vm, *promise_capability0->resolve(), JS::js_undefined(), js_member_value));

        // 3. Return promiseCapability.
        return promise_capability0;
    }(); }));

                // 2. Set idlDict[key] to idlMemberValue.
                return idl_member_value;
            }
            // 7. Otherwise, jsMemberValue is undefined and the member is optional.
            return nullptr;
        }()),
        .finished = TRY([&]() -> JS::ThrowCompletionOr<GC::Ptr<WebIDL::Promise>> {
            // 1. Let key be the identifier of member.
            // 2. If jsDict is either undefined or null, then:
            //     1. Let jsMemberValue be undefined.
            // 3. Otherwise,
            //     1. Let jsMemberValue be ? Get(jsDict, key).
            auto js_member_value = JS::js_undefined();
            if (js_dict.is_object())
                js_member_value = TRY(js_dict.as_object().get("finished"_utf16_fly_string));

            // 4. If jsMemberValue is not undefined, then:
            if (!js_member_value.is_undefined()) {
                // 1. Let idlMemberValue be the result of converting jsMemberValue to an IDL value whose type is the type member is declared to be of.
                auto idl_member_value = TRY(throw_dom_exception_if_needed(vm, [&] { return [&]() -> JS::ThrowCompletionOr<GC::Ref<WebIDL::Promise>> {
        auto& realm = *vm.current_realm();

        // 1. Let promiseCapability be ? NewPromiseCapability(%Promise%).
        auto promise_capability0 = TRY(JS::new_promise_capability(vm, realm.intrinsics().promise_constructor()));

        // 2. Perform ? Call(promiseCapability.[[Resolve]], undefined, « V »).
        TRY(JS::call(vm, *promise_capability0->resolve(), JS::js_undefined(), js_member_value));

        // 3. Return promiseCapability.
        return promise_capability0;
    }(); }));

                // 2. Set idlDict[key] to idlMemberValue.
                return idl_member_value;
            }
            // 7. Otherwise, jsMemberValue is undefined and the member is optional.
            return nullptr;
        }()),
    };
}

} // namespace Web::Bindings