/*
 * Copyright (c) 2018-2022, Andreas Kling <andreas@ladybird.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#pragma once

#include <AK/Function.h>
#include <AK/Noncopyable.h>
#include <AK/RefPtr.h>
#include <AK/WeakPtr.h>
#include <LibGfx/Bitmap.h>
#include <LibGfx/Rect.h>
#include <LibGfx/Size.h>
#include <LibJS/Forward.h>
#include <LibJS/Heap/Cell.h>
#include <LibURL/Origin.h>
#include <LibWeb/DOM/Position.h>
#include <LibWeb/HTML/ActivateTab.h>
#include <LibWeb/HTML/NavigableContainer.h>
#include <LibWeb/HTML/SandboxingFlagSet.h>
#include <LibWeb/HTML/SessionHistoryEntry.h>
#include <LibWeb/HTML/TokenizedFeatures.h>
#include <LibWeb/HTML/VisibilityState.h>
#include <LibWeb/Platform/Timer.h>
#include <LibWeb/TreeNode.h>

namespace Web::HTML {

class BrowsingContext final : public JS::Cell {
    JS_CELL(BrowsingContext, JS::Cell);
    JS_DECLARE_ALLOCATOR(BrowsingContext);

public:
    struct BrowsingContextAndDocument {
        JS::NonnullGCPtr<BrowsingContext> browsing_context;
        JS::NonnullGCPtr<DOM::Document> document;
    };

    static WebIDL::ExceptionOr<BrowsingContextAndDocument> create_a_new_browsing_context_and_document(JS::NonnullGCPtr<Page> page, JS::GCPtr<DOM::Document> creator, JS::GCPtr<DOM::Element> embedder, JS::NonnullGCPtr<BrowsingContextGroup> group);
    static WebIDL::ExceptionOr<BrowsingContextAndDocument> create_a_new_auxiliary_browsing_context_and_document(JS::NonnullGCPtr<Page> page, JS::NonnullGCPtr<HTML::BrowsingContext> opener);

    virtual ~BrowsingContext() override;

    JS::NonnullGCPtr<HTML::TraversableNavigable> top_level_traversable() const;

    JS::GCPtr<BrowsingContext> first_child() const;
    JS::GCPtr<BrowsingContext> next_sibling() const;

    bool is_ancestor_of(BrowsingContext const&) const;
    bool is_familiar_with(BrowsingContext const&) const;

    template<typename Callback>
    TraversalDecision for_each_in_inclusive_subtree(Callback callback) const
    {
        if (callback(*this) == TraversalDecision::Break)
            return TraversalDecision::Break;
        for (auto child = first_child(); child; child = child->next_sibling()) {
            if (child->for_each_in_inclusive_subtree(callback) == TraversalDecision::Break)
                return TraversalDecision::Break;
        }
        return TraversalDecision::Continue;
    }

    template<typename Callback>
    TraversalDecision for_each_in_inclusive_subtree(Callback callback)
    {
        if (callback(*this) == TraversalDecision::Break)
            return TraversalDecision::Break;
        for (auto child = first_child(); child; child = child->next_sibling()) {
            if (child->for_each_in_inclusive_subtree(callback) == TraversalDecision::Break)
                return TraversalDecision::Break;
        }
        return TraversalDecision::Continue;
    }

    template<typename Callback>
    TraversalDecision for_each_in_subtree(Callback callback) const
    {
        for (auto child = first_child(); child; child = child->next_sibling()) {
            if (child->for_each_in_inclusive_subtree(callback) == TraversalDecision::Break)
                return TraversalDecision::Break;
        }
        return TraversalDecision::Continue;
    }

    template<typename Callback>
    TraversalDecision for_each_in_subtree(Callback callback)
    {
        for (auto child = first_child(); child; child = child->next_sibling()) {
            if (child->for_each_in_inclusive_subtree(callback) == TraversalDecision::Break)
                return TraversalDecision::Break;
        }
        return TraversalDecision::Continue;
    }

    bool is_top_level() const;
    bool is_auxiliary() const { return m_is_auxiliary; }

    DOM::Document const* active_document() const;
    DOM::Document* active_document();

    HTML::WindowProxy* window_proxy();
    HTML::WindowProxy const* window_proxy() const;

    void set_window_proxy(JS::GCPtr<WindowProxy>);

    HTML::Window* active_window();
    HTML::Window const* active_window() const;

    Page& page() { return m_page; }
    Page const& page() const { return m_page; }

    u64 virtual_browsing_context_group_id() const { return m_virtual_browsing_context_group_id; }

    JS::GCPtr<BrowsingContext> top_level_browsing_context() const;

    BrowsingContextGroup* group();
    void set_group(BrowsingContextGroup*);

    // https://html.spec.whatwg.org/multipage/browsers.html#bcg-remove
    void remove();

    // https://html.spec.whatwg.org/multipage/origin.html#one-permitted-sandboxed-navigator
    BrowsingContext const* the_one_permitted_sandboxed_navigator() const;

    bool has_navigable_been_destroyed() const;

    JS::GCPtr<BrowsingContext> opener_browsing_context() const { return m_opener_browsing_context; }
    void set_opener_browsing_context(JS::GCPtr<BrowsingContext> browsing_context) { m_opener_browsing_context = browsing_context; }

    void set_is_popup(TokenizedFeature::Popup is_popup) { m_is_popup = is_popup; }

private:
    explicit BrowsingContext(JS::NonnullGCPtr<Page>);

    virtual void visit_edges(Cell::Visitor&) override;

    JS::NonnullGCPtr<Page> m_page;

    // https://html.spec.whatwg.org/multipage/document-sequences.html#browsing-context
    JS::GCPtr<HTML::WindowProxy> m_window_proxy;

    // https://html.spec.whatwg.org/multipage/browsers.html#opener-browsing-context
    JS::GCPtr<BrowsingContext> m_opener_browsing_context;

    // https://html.spec.whatwg.org/multipage/document-sequences.html#opener-origin-at-creation
    Optional<URL::Origin> m_opener_origin_at_creation;

    // https://html.spec.whatwg.org/multipage/browsers.html#is-popup
    TokenizedFeature::Popup m_is_popup { TokenizedFeature::Popup::No };

    // https://html.spec.whatwg.org/multipage/document-sequences.html#is-auxiliary
    bool m_is_auxiliary { false };

    // https://html.spec.whatwg.org/multipage/document-sequences.html#browsing-context-initial-url
    Optional<URL::URL> m_initial_url;

    // https://html.spec.whatwg.org/multipage/document-sequences.html#virtual-browsing-context-group-id
    u64 m_virtual_browsing_context_group_id = { 0 };

    // https://html.spec.whatwg.org/multipage/browsers.html#tlbc-group
    JS::GCPtr<BrowsingContextGroup> m_group;

    JS::GCPtr<BrowsingContext> m_first_child;
    JS::GCPtr<BrowsingContext> m_last_child;
    JS::GCPtr<BrowsingContext> m_next_sibling;
    JS::GCPtr<BrowsingContext> m_previous_sibling;
};

URL::Origin determine_the_origin(Optional<URL::URL> const&, SandboxingFlagSet, Optional<URL::Origin> source_origin);

SandboxingFlagSet determine_the_creation_sandboxing_flags(BrowsingContext const&, JS::GCPtr<DOM::Element> embedder);

// FIXME: Find a better home for these
bool url_matches_about_blank(URL::URL const& url);
bool url_matches_about_srcdoc(URL::URL const& url);

}