#include <LibJS/Runtime/AbstractOperations.h>
#include <LibJS/Runtime/Error.h>
#include <LibJS/Runtime/Realm.h>
#include <LibJS/Runtime/VM.h>
#include <LibJS/Runtime/Value.h>
#include <LibJS/Runtime/ValueInlines.h>
#include <LibWeb/Bindings/CompressionStream.h>
#include <LibWeb/Bindings/ExceptionOrUtils.h>
#include <LibWeb/Bindings/Intrinsics.h>
#include <LibWeb/Compression/CompressionStream.h>
#include <LibWeb/Streams/ReadableStream.h>
#include <LibWeb/Streams/WritableStream.h>
#include <LibWeb/WebIDL/Tracing.h>

namespace Web::Bindings {

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

    
    object.define_direct_property(vm.names.length, JS::Value(1), JS::Attribute::Configurable);
    object.define_direct_property(vm.names.name, JS::PrimitiveString::create(vm, "CompressionStream"_utf16), JS::Attribute::Configurable);
    object.define_direct_property(vm.names.prototype, &ensure_web_prototype<CompressionStreamPrototype>(realm, "CompressionStream"_fly_string), 0);
}

JS::ThrowCompletionOr<GC::Ref<JS::Object>> CompressionStreamConstructor::construct([[maybe_unused]] InterfaceConstructor& constructor, [[maybe_unused]] JS::FunctionObject& new_target)
{
    WebIDL::log_trace(constructor.vm(), "CompressionStreamConstructor::construct");
    auto& vm = constructor.vm();
    [[maybe_unused]] auto& realm = *vm.current_realm();

    // To internally create a new object implementing the interface CompressionStream:

    // 3.2. Let prototype be ? Get(newTarget, "prototype").
    auto prototype = TRY(new_target.get(vm.names.prototype));

    // 3.3. If Type(prototype) is not Object, then:
    if (!prototype.is_object()) {
        // 1. Let targetRealm be ? GetFunctionRealm(newTarget).
        auto* target_realm = TRY(JS::get_function_realm(vm, new_target));

        // 2. Set prototype to the interface prototype object for interface in targetRealm.
        VERIFY(target_realm);
        prototype = &Bindings::ensure_web_prototype<CompressionStreamPrototype>(*target_realm, "CompressionStream"_fly_string);
    }

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

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

    auto impl = TRY(throw_dom_exception_if_needed(vm, [&] { return Compression::CompressionStream::construct_impl(realm, format); }));

    // 7. Set instance.[[Prototype]] to prototype.
    VERIFY(prototype.is_object());
    impl->set_prototype(&prototype.as_object());

    // FIXME: Steps 8...11. of the "internally create a new object implementing the interface CompressionStream" algorithm
    // (https://webidl.spec.whatwg.org/#js-platform-objects) are currently not handled, or are handled within Compression::CompressionStream::construct_impl().

    return *impl;
}

void CompressionStreamPrototype::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(realm.intrinsics().object_prototype());

    auto readable_id = "readable"_utf16_fly_string;
    auto native_readable_getter = JS::NativeFunction::create(realm, readable_getter, 0, readable_id, &realm, "get"sv);
    GC::Ptr<JS::NativeFunction> native_readable_setter;

    // 4. Let configurable be false if attr is unforgeable and true otherwise.
    auto readable_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(readable_id, native_readable_getter, native_readable_setter, readable_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 writable_id = "writable"_utf16_fly_string;
    auto native_writable_getter = JS::NativeFunction::create(realm, writable_getter, 0, writable_id, &realm, "get"sv);
    GC::Ptr<JS::NativeFunction> native_writable_setter;

    // 4. Let configurable be false if attr is unforgeable and true otherwise.
    auto writable_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(writable_id, native_writable_getter, native_writable_setter, writable_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_direct_property(vm.well_known_symbol_to_string_tag(), JS::PrimitiveString::create(vm, "CompressionStream"_utf16), JS::Attribute::Configurable);
}

void CompressionStreamPrototype::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<Compression::CompressionStream*> impl_from(JS::VM& vm, JS::Value js_value)
{

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

[[maybe_unused]] static JS::ThrowCompletionOr<Compression::CompressionStream*> 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(CompressionStreamPrototype::readable_getter)
{
    WebIDL::log_trace(vm, "CompressionStreamPrototype::readable_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->readable(); }));

    return JS::Value(R);
}

JS_DEFINE_NATIVE_FUNCTION(CompressionStreamPrototype::writable_getter)
{
    WebIDL::log_trace(vm, "CompressionStreamPrototype::writable_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->writable(); }));

    return JS::Value(R);
}

// https://webidl.spec.whatwg.org/#idl-enumeration
JS::ThrowCompletionOr<CompressionFormat> convert_to_idl_value_for_compression_format(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 == "brotli"sv)
        return CompressionFormat::Brotli;
    if (value_as_string == "deflate"sv)
        return CompressionFormat::Deflate;
    if (value_as_string == "deflate-raw"sv)
        return CompressionFormat::DeflateRaw;
    if (value_as_string == "gzip"sv)
        return CompressionFormat::Gzip;
    return vm.throw_completion<JS::TypeError>(JS::ErrorType::InvalidEnumerationValue, value_as_string, "CompressionFormat");
}

// https://webidl.spec.whatwg.org/#idl-enumeration
Utf16String idl_enum_to_string(CompressionFormat 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 CompressionFormat::Brotli:
        return "brotli"_utf16;
    case CompressionFormat::Deflate:
        return "deflate"_utf16;
    case CompressionFormat::DeflateRaw:
        return "deflate-raw"_utf16;
    case CompressionFormat::Gzip:
        return "gzip"_utf16;
    }
    VERIFY_NOT_REACHED();
}

} // namespace Web::Bindings