/*

 * Copyright (c) 2023, Tim Flynn <trflynn89@serenityos.org>

 *

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

 */

#pragma once

#include <AK/String.h>

#include <AK/Variant.h>

#include <LibJS/Heap/Cell.h>

#include <LibJS/Heap/GCPtr.h>

#include <LibWeb/Forward.h>

namespace Web::DOM {

// https://dom.spec.whatwg.org/#concept-slotable

using Slottable = Variant<JS::NonnullGCPtr<Element>, JS::NonnullGCPtr<Text>>;

// https://dom.spec.whatwg.org/#mixin-slotable

class SlottableMixin {

public:

    virtual ~SlottableMixin();

    String const& slottable_name() const { return m_name; } // Not called `name` to distinguish from `Element::name`.

    void set_slottable_name(String name) { m_name = move(name); }

    JS::GCPtr<HTML::HTMLSlotElement> assigned_slot();

    JS::GCPtr<HTML::HTMLSlotElement> assigned_slot_internal() const { return m_assigned_slot; }

    void set_assigned_slot(JS::GCPtr<HTML::HTMLSlotElement> assigned_slot) { m_assigned_slot = assigned_slot; }

    JS::GCPtr<HTML::HTMLSlotElement> manual_slot_assignment() { return m_manual_slot_assignment; }

    void set_manual_slot_assignment(JS::GCPtr<HTML::HTMLSlotElement> manual_slot_assignment) { m_manual_slot_assignment = manual_slot_assignment; }

protected:

    void visit_edges(JS::Cell::Visitor&);

private:

    // https://dom.spec.whatwg.org/#slotable-name

    String m_name;

    // https://dom.spec.whatwg.org/#slotable-assigned-slot

    JS::GCPtr<HTML::HTMLSlotElement> m_assigned_slot;

    // https://dom.spec.whatwg.org/#slottable-manual-slot-assignment

    JS::GCPtr<HTML::HTMLSlotElement> m_manual_slot_assignment;

};

enum class OpenFlag {

    Set,

    Unset,

};

JS::GCPtr<HTML::HTMLSlotElement> assigned_slot_for_node(JS::NonnullGCPtr<Node>);

bool is_an_assigned_slottable(JS::NonnullGCPtr<Node>);

JS::GCPtr<HTML::HTMLSlotElement> find_a_slot(Slottable const&, OpenFlag = OpenFlag::Unset);

Vector<Slottable> find_slottables(JS::NonnullGCPtr<HTML::HTMLSlotElement>);

void assign_slottables(JS::NonnullGCPtr<HTML::HTMLSlotElement>);

void assign_slottables_for_a_tree(JS::NonnullGCPtr<Node>);

void assign_a_slot(Slottable const&);

void signal_a_slot_change(JS::NonnullGCPtr<HTML::HTMLSlotElement>);

}