/*

 * Copyright (c) 2020-2023, Linus Groh <linusg@serenityos.org>

 *

 * SPDX-License-Identifier: BSD-2-Clause

 */

#include <AK/TypeCasts.h>

#include <LibJS/Runtime/ArrayBuffer.h>

#include <LibJS/Runtime/ArrayBufferConstructor.h>

#include <LibJS/Runtime/DataView.h>

#include <LibJS/Runtime/Error.h>

#include <LibJS/Runtime/GlobalObject.h>

#include <LibJS/Runtime/TypedArray.h>

namespace JS {

JS_DEFINE_ALLOCATOR(ArrayBufferConstructor);

ArrayBufferConstructor::ArrayBufferConstructor(Realm& realm)

    : NativeFunction(realm.vm().names.ArrayBuffer.as_string(), realm.intrinsics().function_prototype())

{

}

void ArrayBufferConstructor::initialize(Realm& realm)

{

    auto& vm = this->vm();

    Base::initialize(realm);

    // 25.1.5.2 ArrayBuffer.prototype, https://tc39.es/ecma262/#sec-arraybuffer.prototype

    define_direct_property(vm.names.prototype, realm.intrinsics().array_buffer_prototype(), 0);

    u8 attr = Attribute::Writable | Attribute::Configurable;

    define_native_function(realm, vm.names.isView, is_view, 1, attr);

    // 25.1.6.7 ArrayBuffer.prototype [ @@toStringTag ], https://tc39.es/ecma262/#sec-arraybuffer.prototype-@@tostringtag

    define_native_accessor(realm, vm.well_known_symbol_species(), symbol_species_getter, {}, Attribute::Configurable);

    define_direct_property(vm.names.length, Value(1), Attribute::Configurable);

}

// 25.1.4.1 ArrayBuffer ( length [ , options ] ), https://tc39.es/ecma262/#sec-arraybuffer-length

ThrowCompletionOr<Value> ArrayBufferConstructor::call()

{

    auto& vm = this->vm();

    // 1. If NewTarget is undefined, throw a TypeError exception.

    return vm.throw_completion<TypeError>(ErrorType::ConstructorWithoutNew, vm.names.ArrayBuffer);

}

// 25.1.4.1 ArrayBuffer ( length [ , options ] ), https://tc39.es/ecma262/#sec-arraybuffer-length

ThrowCompletionOr<NonnullGCPtr<Object>> ArrayBufferConstructor::construct(FunctionObject& new_target)

{

    auto& vm = this->vm();

    auto length = vm.argument(0);

    auto options = vm.argument(1);

    // 2. Let byteLength be ? ToIndex(length).

    auto byte_length_or_error = length.to_index(vm);

    if (byte_length_or_error.is_error()) {

        auto error = byte_length_or_error.release_error();

        if (error.value()->is_object() && is<RangeError>(error.value()->as_object())) {

            // Re-throw more specific RangeError

            return vm.throw_completion<RangeError>(ErrorType::InvalidLength, "array buffer");

        }

        return error;

    }

    // 3. Let requestedMaxByteLength be ? GetArrayBufferMaxByteLengthOption(options).

    auto requested_max_byte_length = TRY(get_array_buffer_max_byte_length_option(vm, options));

    // 3. Return ? AllocateArrayBuffer(NewTarget, byteLength, requestedMaxByteLength).

    return *TRY(allocate_array_buffer(vm, new_target, byte_length_or_error.release_value(), requested_max_byte_length));

}

// 25.1.5.1 ArrayBuffer.isView ( arg ), https://tc39.es/ecma262/#sec-arraybuffer.isview

JS_DEFINE_NATIVE_FUNCTION(ArrayBufferConstructor::is_view)

{

    auto arg = vm.argument(0);

    // 1. If arg is not an Object, return false.

    if (!arg.is_object())

        return Value(false);

    // 2. If arg has a [[ViewedArrayBuffer]] internal slot, return true.

    if (arg.as_object().is_typed_array())

        return Value(true);

    if (is<DataView>(arg.as_object()))

        return Value(true);

    // 3. Return false.

    return Value(false);

}

// 25.1.5.3 get ArrayBuffer [ @@species ], https://tc39.es/ecma262/#sec-get-arraybuffer-@@species

JS_DEFINE_NATIVE_FUNCTION(ArrayBufferConstructor::symbol_species_getter)

{

    // 1. Return the this value.

    return vm.this_value();

}

}