/*
 * Copyright (c) 2020, Andreas Kling <kling@serenityos.org>
 * Copyright (c) 2020-2021, Linus Groh <linusg@serenityos.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#include <AK/Function.h>
#include <LibJS/Runtime/Array.h>
#include <LibJS/Runtime/Error.h>
#include <LibJS/Runtime/GlobalObject.h>

namespace JS {

// 10.4.2.2 ArrayCreate ( length [ , proto ] ), https://tc39.es/ecma262/#sec-arraycreate
Array* Array::create(GlobalObject& global_object, size_t length, Object* prototype)
{
    auto& vm = global_object.vm();
    if (length > NumericLimits<u32>::max()) {
        vm.throw_exception<RangeError>(global_object, ErrorType::InvalidLength, "array");
        return nullptr;
    }
    if (!prototype)
        prototype = global_object.array_prototype();
    auto* array = global_object.heap().allocate<Array>(global_object, *prototype);
    array->internal_define_own_property(vm.names.length, { .value = Value(length), .writable = true, .enumerable = false, .configurable = false });
    return array;
}

// 7.3.17 CreateArrayFromList ( elements ), https://tc39.es/ecma262/#sec-createarrayfromlist
Array* Array::create_from(GlobalObject& global_object, Vector<Value> const& elements)
{
    // 1. Assert: elements is a List whose elements are all ECMAScript language values.

    // 2. Let array be ! ArrayCreate(0).
    auto* array = Array::create(global_object, 0);

    // 3. Let n be 0.
    // 4. For each element e of elements, do
    for (u32 n = 0; n < elements.size(); ++n) {
        // a. Perform ! CreateDataPropertyOrThrow(array, ! ToString(𝔽(n)), e).
        array->create_data_property_or_throw(n, elements[n]);
        // b. Set n to n + 1.
    }

    // 5. Return array.
    return array;
}

Array::Array(Object& prototype)
    : Object(prototype)
{
}

void Array::initialize(GlobalObject& global_object)
{
    auto& vm = this->vm();
    Object::initialize(global_object);
    define_native_property(vm.names.length, length_getter, length_setter, Attribute::Writable);
}

Array::~Array()
{
}

Array* Array::typed_this(VM& vm, GlobalObject& global_object)
{
    auto* this_object = vm.this_value(global_object).to_object(global_object);
    if (!this_object)
        return {};
    if (!this_object->is_array()) {
        vm.throw_exception<TypeError>(global_object, ErrorType::NotAn, "Array");
        return nullptr;
    }
    return static_cast<Array*>(this_object);
}

JS_DEFINE_NATIVE_GETTER(Array::length_getter)
{
    auto* this_object = vm.this_value(global_object).to_object(global_object);
    if (!this_object)
        return {};

    return Value(this_object->indexed_properties().array_like_size());
}

JS_DEFINE_NATIVE_SETTER(Array::length_setter)
{
    auto* this_object = vm.this_value(global_object).to_object(global_object);
    if (!this_object)
        return;

    auto length = value.to_number(global_object);
    if (vm.exception())
        return;

    u32 val = length.as_double();

    if (val != length.as_double()
        || length.is_nan()
        || length.is_infinity()
        || length.as_double() < 0
        || length.as_double() > NumericLimits<u32>::max()) {
        vm.throw_exception<RangeError>(global_object, ErrorType::InvalidLength, "array");
        return;
    }
    this_object->indexed_properties().set_array_like_size(val);
}

}