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

#ifndef NET_REPORTING_REPORTING_ENDPOINT_H_
#define NET_REPORTING_REPORTING_ENDPOINT_H_

#include <optional>
#include <string>
#include <vector>

#include "base/time/time.h"
#include "base/unguessable_token.h"
#include "net/base/net_export.h"
#include "net/base/network_anonymization_key.h"
#include "net/reporting/reporting_target_type.h"
#include "url/gurl.h"
#include "url/origin.h"

namespace net {

// Identifies an endpoint group.
struct NET_EXPORT ReportingEndpointGroupKey {
  // Constructs a default ReportingEndpointGroupKey.
  ReportingEndpointGroupKey();

  // Constructs a ReportingEndpointGroupKey with a null `reporting_source`.
  ReportingEndpointGroupKey(
      const NetworkAnonymizationKey& network_anonymization_key,
      const std::optional<url::Origin>& origin,
      const std::string& group_name,
      ReportingTargetType target_type);

  // Constructs a ReportingEndpointGroupKey with the given parameters.
  ReportingEndpointGroupKey(
      const NetworkAnonymizationKey& network_anonymization_key,
      std::optional<base::UnguessableToken> reporting_source,
      const std::optional<url::Origin>& origin,
      const std::string& group_name,
      ReportingTargetType target_type);

  // Constructs a ReportingEndpointGroupKey with the given `reporting_source`
  // and all other members from `other`.
  ReportingEndpointGroupKey(
      const ReportingEndpointGroupKey& other,
      const std::optional<base::UnguessableToken>& reporting_source);

  ReportingEndpointGroupKey(const ReportingEndpointGroupKey& other);
  ReportingEndpointGroupKey(ReportingEndpointGroupKey&& other);

  ReportingEndpointGroupKey& operator=(const ReportingEndpointGroupKey&);
  ReportingEndpointGroupKey& operator=(ReportingEndpointGroupKey&&);

  ~ReportingEndpointGroupKey();

  std::string ToString() const;

  // True if this endpoint "group" is actually being used to represent a single
  // V1 document endpoint.
  bool IsDocumentEndpoint() const { return reporting_source.has_value(); }

  // True if this endpoint "group" is set by the enterprise policy.
  bool IsEnterpriseEndpoint() const {
    return target_type == ReportingTargetType::kEnterprise;
  }

  // Source token for the document or worker which configured this endpoint, if
  // this was configured with the Reporting-Endpoints header. For endpoint
  // groups configured with the Report-To header and enterprise endpoint groups,
  // this will be nullopt.
  std::optional<base::UnguessableToken> reporting_source;

  // The NetworkAnonymizationKey the group is scoped to. Needed to prevent
  // leaking third party contexts across sites. This is empty for enterprise
  // groups.
  NetworkAnonymizationKey network_anonymization_key;

  // Origin that configured this endpoint group. For enterprise endpoint groups,
  // this will be nullopt.
  std::optional<url::Origin> origin;

  // Name of the endpoint group (defaults to "default" during header parsing).
  std::string group_name;

  // Used to distinguish web developer and enterprise entities so that
  // enterprise reports aren’t sent to web developer endpoints and web developer
  // reports aren’t sent to enterprise endpoints.
  ReportingTargetType target_type = ReportingTargetType::kDeveloper;

  friend bool operator==(const ReportingEndpointGroupKey&,
                         const ReportingEndpointGroupKey&) = default;

  friend auto operator<=>(const ReportingEndpointGroupKey&,
                          const ReportingEndpointGroupKey&) = default;
};

NET_EXPORT bool operator<(const ReportingEndpointGroupKey& lhs,
                          const ReportingEndpointGroupKey& rhs);
NET_EXPORT bool operator>(const ReportingEndpointGroupKey& lhs,
                          const ReportingEndpointGroupKey& rhs);

// The configuration by an origin to use an endpoint for report delivery.
// TODO(crbug.com/41430426): Track endpoint failures for garbage collection.
struct NET_EXPORT ReportingEndpoint {
  struct NET_EXPORT EndpointInfo {
    static const int kDefaultPriority;
    static const int kDefaultWeight;

    // The endpoint to which reports may be delivered. (Origins may configure
    // many.)
    GURL url;

    // Priority when multiple endpoints are configured for an origin; endpoints
    // with numerically lower priorities are used first.
    int priority = kDefaultPriority;

    // Weight when multiple endpoints are configured for an origin with the same
    // priority; among those with the same priority, each endpoint has a chance
    // of being chosen that is proportional to its weight.
    int weight = kDefaultWeight;

    friend bool operator==(const EndpointInfo& lhs,
                           const EndpointInfo& rhs) = default;
  };

  struct Statistics {
    // The number of attempted uploads that we've made for this endpoint.
    int attempted_uploads = 0;
    // The number of uploads that have succeeded for this endpoint.
    int successful_uploads = 0;
    // The number of individual reports that we've attempted to upload for this
    // endpoint.  (Failed uploads will cause a report to be counted multiple
    // times, once for each attempt.)
    int attempted_reports = 0;
    // The number of individual reports that we've successfully uploaded for
    // this endpoint.
    int successful_reports = 0;

    friend bool operator==(const Statistics& lhs,
                           const Statistics& rhs) = default;
  };

  // Constructs an invalid ReportingEndpoint.
  ReportingEndpoint();

  ReportingEndpoint(const ReportingEndpointGroupKey& group,
                    const EndpointInfo& info);

  ReportingEndpoint(const ReportingEndpoint& other);
  ReportingEndpoint(ReportingEndpoint&& other);

  ReportingEndpoint& operator=(const ReportingEndpoint&);
  ReportingEndpoint& operator=(ReportingEndpoint&&);

  friend bool operator==(const ReportingEndpoint& lhs,
                         const ReportingEndpoint& rhs) = default;

  ~ReportingEndpoint();

  bool is_valid() const;
  explicit operator bool() const { return is_valid(); }

  // Identifies the endpoint group to which this endpoint belongs.
  ReportingEndpointGroupKey group_key;

  // URL, priority, and weight of the endpoint.
  EndpointInfo info;

  // Information about the number of deliveries that we've attempted for this
  // endpoint. Not persisted across restarts.
  Statistics stats;
};

// Marks whether a given endpoint group is configured to include its origin's
// subdomains.
enum class OriginSubdomains { EXCLUDE, INCLUDE, DEFAULT = EXCLUDE };

// Represents an endpoint group set by an origin via Report-To header.
struct NET_EXPORT ReportingEndpointGroup {
  ReportingEndpointGroup();

  ReportingEndpointGroup(const ReportingEndpointGroup& other);

  ~ReportingEndpointGroup();

  ReportingEndpointGroupKey group_key;

  // Whether this group applies to subdomains of its origin.
  OriginSubdomains include_subdomains = OriginSubdomains::DEFAULT;

  // Time for which the endpoint group remains valid after it is set.
  base::TimeDelta ttl;

  // Endpoints in this group.
  std::vector<ReportingEndpoint::EndpointInfo> endpoints;
};

// Representation of an endpoint group used for in-memory and persistent
// storage.
struct NET_EXPORT CachedReportingEndpointGroup {
  CachedReportingEndpointGroup(const ReportingEndpointGroupKey& group_key,
                               OriginSubdomains include_subdomains,
                               base::Time expires,
                               base::Time last_used);

  // |now| is the time at which the header was processed.
  CachedReportingEndpointGroup(const ReportingEndpointGroup& endpoint_group,
                               base::Time now);

  // Origin and group name.
  ReportingEndpointGroupKey group_key;

  // Whether this group applies to subdomains of |group_key.origin|.
  OriginSubdomains include_subdomains = OriginSubdomains::DEFAULT;

  // When this group's max_age expires.
  // (base::Time is used here instead of base::TimeTicks for ease of
  // serialization for persistent storage, and because it is more appropriate
  // for expiration times, as per //base/time/time.h.)
  base::Time expires;

  // Last time that this group was accessed for a delivery or updated via a
  // new header.
  base::Time last_used;
};

}  // namespace net

#endif  // NET_REPORTING_REPORTING_ENDPOINT_H_