/*

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

 *

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

 */

#pragma once

#include <AK/ByteBuffer.h>

#include <AK/HashMap.h>

#include <AK/HashTable.h>

#include <AK/Noncopyable.h>

#include <AK/RefCounted.h>

#include <AK/WeakPtr.h>

#include <AK/Weakable.h>

#include <LibGfx/Forward.h>

#include <LibHTTP/HeaderMap.h>

#include <LibURL/URL.h>

#include <LibWeb/Forward.h>

#include <LibWeb/Loader/LoadRequest.h>

namespace Web {

class ResourceClient;

class Resource : public RefCounted<Resource> {

    AK_MAKE_NONCOPYABLE(Resource);

    AK_MAKE_NONMOVABLE(Resource);

public:

    enum class Type {

        Generic,

    };

    static NonnullRefPtr<Resource> create(Badge<ResourceLoader>, Type, LoadRequest const&);

    virtual ~Resource();

    Type type() const { return m_type; }

    enum class State {

        Pending,

        Loaded,

        Failed,

    };

    bool is_pending() const { return m_state == State::Pending; }

    bool is_loaded() const { return m_state == State::Loaded; }

    bool is_failed() const { return m_state == State::Failed; }

    ByteString const& error() const { return m_error; }

    bool has_encoded_data() const { return !m_encoded_data.is_empty(); }

    const URL::URL& url() const { return m_request.url(); }

    ByteBuffer const& encoded_data() const { return m_encoded_data; }

    [[nodiscard]] HTTP::HeaderMap const& response_headers() const { return m_response_headers; }

    [[nodiscard]] Optional<u32> status_code() const { return m_status_code; }

    void register_client(Badge<ResourceClient>, ResourceClient&);

    void unregister_client(Badge<ResourceClient>, ResourceClient&);

    bool has_encoding() const { return m_encoding.has_value(); }

    Optional<ByteString> const& encoding() const { return m_encoding; }

    ByteString const& mime_type() const { return m_mime_type; }

    void for_each_client(Function<void(ResourceClient&)>);

    void did_load(Badge<ResourceLoader>, ReadonlyBytes data, HTTP::HeaderMap const&, Optional<u32> status_code);

    void did_fail(Badge<ResourceLoader>, ByteString const& error, Optional<u32> status_code);

protected:

    explicit Resource(Type, LoadRequest const&);

    Resource(Type, Resource&);

    LoadRequest request() const { return m_request; }

private:

    LoadRequest m_request;

    ByteBuffer m_encoded_data;

    Type m_type { Type::Generic };

    State m_state { State::Pending };

    ByteString m_error;

    Optional<ByteString> m_encoding;

    ByteString m_mime_type;

    HTTP::HeaderMap m_response_headers;

    Optional<u32> m_status_code;

    HashTable<ResourceClient*> m_clients;

};

class ResourceClient : public Weakable<ResourceClient> {

public:

    virtual ~ResourceClient();

    virtual void resource_did_load() { }

    virtual void resource_did_fail() { }

protected:

    virtual Resource::Type client_type() const { return Resource::Type::Generic; }

    Resource* resource() { return m_resource; }

    Resource const* resource() const { return m_resource; }

    void set_resource(Resource*);

private:

    RefPtr<Resource> m_resource;

};

}