/*
 * Copyright (c) 2021, Luke Wilde <lukew@serenityos.org>
 * Copyright (c) 2022, Linus Groh <linusg@serenityos.org>
 *
 * SPDX-License-Identifier: BSD-2-Clause
 */

#pragma once

#include <LibJS/Forward.h>
#include <LibURL/Origin.h>
#include <LibURL/URL.h>
#include <LibWeb/Forward.h>
#include <LibWeb/HTML/EventLoop/EventLoop.h>
#include <LibWeb/HTML/Scripting/ModuleMap.h>
#include <LibWeb/HTML/Scripting/SerializedEnvironmentSettingsObject.h>

namespace Web::HTML {

// https://html.spec.whatwg.org/multipage/webappapis.html#environment
struct Environment : public JS::Cell {
    JS_CELL(Environment, JS::Cell);

public:
    virtual ~Environment() override;

    // An id https://html.spec.whatwg.org/multipage/webappapis.html#concept-environment-id
    String id;

    // https://html.spec.whatwg.org/multipage/webappapis.html#concept-environment-creation-url
    URL::URL creation_url;

    // https://html.spec.whatwg.org/multipage/webappapis.html#concept-environment-top-level-creation-url
    URL::URL top_level_creation_url;

    // https://html.spec.whatwg.org/multipage/webappapis.html#concept-environment-top-level-origin
    URL::Origin top_level_origin;

    // https://html.spec.whatwg.org/multipage/webappapis.html#concept-environment-target-browsing-context
    JS::GCPtr<BrowsingContext> target_browsing_context;

    // FIXME: An active service worker https://html.spec.whatwg.org/multipage/webappapis.html#concept-environment-active-service-worker

    // https://html.spec.whatwg.org/multipage/webappapis.html#concept-environment-execution-ready-flag
    bool execution_ready { false };

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

enum class RunScriptDecision {
    Run,
    DoNotRun,
};

// https://html.spec.whatwg.org/multipage/webappapis.html#environment-settings-object
struct EnvironmentSettingsObject : public Environment {
    JS_CELL(EnvironmentSettingsObject, Environment);

public:
    virtual ~EnvironmentSettingsObject() override;
    virtual void initialize(JS::Realm&) override;

    // https://html.spec.whatwg.org/multipage/webappapis.html#concept-environment-target-browsing-context
    JS::ExecutionContext& realm_execution_context();

    // https://html.spec.whatwg.org/multipage/webappapis.html#concept-settings-object-module-map
    ModuleMap& module_map();

    // https://html.spec.whatwg.org/multipage/webappapis.html#responsible-document
    virtual JS::GCPtr<DOM::Document> responsible_document() = 0;

    // https://html.spec.whatwg.org/multipage/webappapis.html#api-url-character-encoding
    virtual String api_url_character_encoding() = 0;

    // https://html.spec.whatwg.org/multipage/webappapis.html#api-base-url
    virtual URL::URL api_base_url() = 0;

    // https://html.spec.whatwg.org/multipage/webappapis.html#concept-settings-object-origin
    virtual URL::Origin origin() = 0;

    // A policy container https://html.spec.whatwg.org/multipage/webappapis.html#concept-settings-object-policy-container
    virtual PolicyContainer policy_container() = 0;

    // https://html.spec.whatwg.org/multipage/webappapis.html#concept-settings-object-cross-origin-isolated-capability
    virtual CanUseCrossOriginIsolatedAPIs cross_origin_isolated_capability() = 0;

    URL::URL parse_url(StringView);

    JS::Realm& realm();
    JS::Object& global_object();
    EventLoop& responsible_event_loop();

    // https://fetch.spec.whatwg.org/#concept-fetch-group
    Vector<JS::NonnullGCPtr<Fetch::Infrastructure::FetchRecord>>& fetch_group() { return m_fetch_group; }

    RunScriptDecision can_run_script();
    void prepare_to_run_script();
    void clean_up_after_running_script();

    void prepare_to_run_callback();
    void clean_up_after_running_callback();

    void push_onto_outstanding_rejected_promises_weak_set(JS::Promise*);

    // Returns true if removed, false otherwise.
    bool remove_from_outstanding_rejected_promises_weak_set(JS::Promise*);

    void push_onto_about_to_be_notified_rejected_promises_list(JS::NonnullGCPtr<JS::Promise>);

    // Returns true if removed, false otherwise.
    bool remove_from_about_to_be_notified_rejected_promises_list(JS::NonnullGCPtr<JS::Promise>);

    void notify_about_rejected_promises(Badge<EventLoop>);

    bool is_scripting_enabled() const;
    bool is_scripting_disabled() const;

    bool module_type_allowed(StringView module_type) const;

    void disallow_further_import_maps();

    SerializedEnvironmentSettingsObject serialize();

    JS::NonnullGCPtr<StorageAPI::StorageManager> storage_manager();

    [[nodiscard]] bool discarded() const { return m_discarded; }
    void set_discarded(bool b) { m_discarded = b; }

protected:
    explicit EnvironmentSettingsObject(NonnullOwnPtr<JS::ExecutionContext>);

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

private:
    NonnullOwnPtr<JS::ExecutionContext> m_realm_execution_context;
    JS::GCPtr<ModuleMap> m_module_map;

    JS::GCPtr<EventLoop> m_responsible_event_loop;

    // https://html.spec.whatwg.org/multipage/webappapis.html#outstanding-rejected-promises-weak-set
    // The outstanding rejected promises weak set must not create strong references to any of its members, and implementations are free to limit its size, e.g. by removing old entries from it when new ones are added.
    Vector<JS::GCPtr<JS::Promise>> m_outstanding_rejected_promises_weak_set;

    // https://html.spec.whatwg.org/multipage/webappapis.html#about-to-be-notified-rejected-promises-list
    Vector<JS::Handle<JS::Promise>> m_about_to_be_notified_rejected_promises_list;

    // https://fetch.spec.whatwg.org/#concept-fetch-record
    // A fetch group holds an ordered list of fetch records
    Vector<JS::NonnullGCPtr<Fetch::Infrastructure::FetchRecord>> m_fetch_group;

    // https://storage.spec.whatwg.org/#api
    // Each environment settings object has an associated StorageManager object.
    JS::GCPtr<StorageAPI::StorageManager> m_storage_manager;

    // https://w3c.github.io/ServiceWorker/#service-worker-client-discarded-flag
    // A service worker client has an associated discarded flag. It is initially unset.
    bool m_discarded { false };
};

EnvironmentSettingsObject& incumbent_settings_object();
JS::Realm& incumbent_realm();
JS::Object& incumbent_global_object();
EnvironmentSettingsObject& current_settings_object();
JS::Object& current_global_object();
JS::Realm& relevant_realm(JS::Object const&);
EnvironmentSettingsObject& relevant_settings_object(JS::Object const&);
EnvironmentSettingsObject& relevant_settings_object(DOM::Node const&);
JS::Object& relevant_global_object(JS::Object const&);
JS::Realm& entry_realm();
EnvironmentSettingsObject& entry_settings_object();
JS::Object& entry_global_object();
JS::VM& relevant_agent(JS::Object const&);
[[nodiscard]] bool is_secure_context(Environment const&);
[[nodiscard]] bool is_non_secure_context(Environment const&);

}