/*

 * Copyright (c) 2020-2021, Andreas Kling <kling@serenityos.org>

 * Copyright (c) 2020-2021, Linus Groh <linusg@serenityos.org>

 * Copyright (c) 2020-2022, Idan Horowitz <idan.horowitz@serenityos.org>

 *

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

 */

#pragma once

#include <LibJS/Runtime/BigInt.h>

#include <LibJS/Runtime/PrimitiveString.h>

#include <LibJS/Runtime/Value.h>

namespace JS {

struct ValueTraits : public Traits<Value> {

    static unsigned hash(Value value)

    {

        VERIFY(!value.is_empty());

        if (value.is_string()) {

            // FIXME: Propagate this error.

            return value.as_string().byte_string().hash();

        }

        if (value.is_bigint())

            return value.as_bigint().big_integer().hash();

        // In the IEEE 754 standard a NaN value is encoded as any value from 0x7ff0000000000001 to 0x7fffffffffffffff,

        // with the least significant bits (referred to as the 'payload') carrying some kind of diagnostic information

        // indicating the source of the NaN. Since ECMA262 does not differentiate between different kinds of NaN values,

        // Sets and Maps must not differentiate between them either.

        // This is achieved by replacing any NaN value by a canonical qNaN.

        if (value.is_nan())

            value = js_nan();

        return u64_hash(value.encoded()); // FIXME: Is this the best way to hash pointers, doubles & ints?

    }

    static bool equals(Value const a, Value const b)

    {

        return same_value(a, b);

    }

};

}