services/network/public/cpp/client_hints.h

// Copyright 2017 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef SERVICES_NETWORK_PUBLIC_CPP_CLIENT_HINTS_H_
#define SERVICES_NETWORK_PUBLIC_CPP_CLIENT_HINTS_H_

#include <stddef.h>
#include <string>

#include "base/component_export.h"
#include "base/containers/flat_map.h"
#include "base/time/time.h"
#include "services/network/public/mojom/web_client_hints_types.mojom-shared.h"
#include "third_party/abseil-cpp/absl/types/optional.h"

namespace network {

using ClientHintToNameMap =
    base::flat_map<network::mojom::WebClientHintsType, std::string>;

// Mapping from WebClientHintsType to the hint's name in Accept-CH header.
// The ordering matches the ordering of enums in
// services/network/public/mojom/web_client_hints_types.mojom
COMPONENT_EXPORT(NETWORK_CPP)
const ClientHintToNameMap& GetClientHintToNameMap();

// Tries to parse an Accept-CH header. Returns absl::nullopt if parsing
// failed and the header should be ignored; otherwise returns a (possibly
// empty) list of hints to accept.
absl::optional<std::vector<network::mojom::WebClientHintsType>>
    COMPONENT_EXPORT(NETWORK_CPP)
        ParseClientHintsHeader(const std::string& header);

// Tries to parse Accept-CH-Lifetime. Returns base::TimeDelta() if unsuccessful.
base::TimeDelta COMPONENT_EXPORT(NETWORK_CPP)
    ParseAcceptCHLifetime(const std::string& header);

// Suggest the alternate client hint to use if the checked one is deprecated.
absl::optional<network::mojom::WebClientHintsType> COMPONENT_EXPORT(NETWORK_CPP)
    SuggestAlternateClientHintIfDeprecated(
        const network::mojom::WebClientHintsType type);

}  // namespace network

#endif  // SERVICES_NETWORK_PUBLIC_CPP_CLIENT_HINTS_H_