// Copyright 2018 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

#ifndef GOOGLE_CLOUD_CPP_GOOGLE_CLOUD_STORAGE_NOTIFICATION_METADATA_H
#define GOOGLE_CLOUD_CPP_GOOGLE_CLOUD_STORAGE_NOTIFICATION_METADATA_H

#include "google/cloud/storage/version.h"
#include "google/cloud/status_or.h"
#include <map>
#include <string>
#include <vector>

namespace google {
namespace cloud {
namespace storage {
inline namespace STORAGE_CLIENT_NS {
namespace internal {
struct NotificationMetadataParser;
}  // namespace internal

/**
 * Represents the metadata for a Google Cloud Storage Notification resource.
 *
 * Notifications send information about changes to objects in your buckets to
 * Cloud Pub/Sub.
 *
 * @see https://cloud.google.com/storage/docs/pubsub-notifications for general
 *     information on Google Cloud Storage Notifications.
 * @see https://cloud.google.com/pubsub/ for general information on Google
 *     Cloud Pub/Sub service.
 */
class NotificationMetadata {
 public:
  NotificationMetadata() = default;

  /**
   * Returns the payload for a call to `Notifications: insert`.
   */
  std::string JsonPayloadForInsert() const;

  //@{
  /// @name Accessors and modifiers to the custom attributes.
  bool has_custom_attribute(std::string const& key) const {
    return custom_attributes_.end() != custom_attributes_.find(key);
  }

  std::string const& custom_attribute(std::string const& key) const {
    return custom_attributes_.at(key);
  }

  /// Delete a custom attribute. This is a no-op if the key does not exist.
  NotificationMetadata& delete_custom_attribute(std::string const& key) {
    auto i = custom_attributes_.find(key);
    if (i == custom_attributes_.end()) {
      return *this;
    }
    custom_attributes_.erase(i);
    return *this;
  }

  /// Insert or update the custom attribute.
  NotificationMetadata& upsert_custom_attributes(std::string key,
                                                 std::string value) {
    auto i = custom_attributes_.lower_bound(key);
    if (i == custom_attributes_.end() || i->first != key) {
      custom_attributes_.emplace_hint(i, std::move(key), std::move(value));
    } else {
      i->second = std::move(value);
    }
    return *this;
  }

  /// Full accessors for the custom attributes.
  std::map<std::string, std::string> const& custom_attributes() const {
    return custom_attributes_;
  }
  std::map<std::string, std::string>& mutable_custom_attributes() {
    return custom_attributes_;
  }
  //@}

  std::string const& etag() const { return etag_; }

  //@{
  /**
   * @name Accessors and modifiers to the event types list.
   *
   * Define the list of event types that this notification will include.
   *
   * @see https://cloud.google.com/storage/docs/pubsub-notifications#events for
   *     a description of valid even types.
   */
  std::size_t event_type_size() const { return event_types_.size(); }
  std::string const& event_type(std::size_t index) const {
    return event_types_.at(index);
  }

  NotificationMetadata& append_event_type(std::string e) {
    event_types_.emplace_back(std::move(e));
    return *this;
  }

  std::vector<std::string> const& event_types() const { return event_types_; }
  std::vector<std::string>& mutable_event_types() { return event_types_; }
  //@}

  std::string const& id() const { return id_; }
  std::string const& kind() const { return kind_; }

  std::string const& object_name_prefix() const { return object_name_prefix_; }
  NotificationMetadata& set_object_name_prefix(std::string v) {
    object_name_prefix_ = std::move(v);
    return *this;
  }

  std::string const& payload_format() const { return payload_format_; }
  NotificationMetadata& set_payload_format(std::string v) {
    payload_format_ = std::move(v);
    return *this;
  }

  std::string const& self_link() const { return self_link_; }

  std::string const& topic() const { return topic_; }
  NotificationMetadata& set_topic(std::string v) {
    topic_ = std::move(v);
    return *this;
  }

 private:
  friend struct internal::NotificationMetadataParser;
  friend std::ostream& operator<<(std::ostream& os,
                                  NotificationMetadata const& rhs);

  // Keep the fields in alphabetical order.
  std::map<std::string, std::string> custom_attributes_;
  std::string etag_;
  std::vector<std::string> event_types_;
  std::string id_;
  std::string kind_;
  std::string object_name_prefix_;
  std::string payload_format_;
  std::string self_link_;
  std::string topic_;
};

inline bool operator==(NotificationMetadata const& lhs,
                       NotificationMetadata const& rhs) {
  return std::tie(lhs.id(), lhs.custom_attributes(), lhs.etag(),
                  lhs.event_types(), lhs.kind(), lhs.object_name_prefix(),
                  lhs.payload_format(), lhs.self_link(), lhs.topic()) ==
         std::tie(rhs.id(), rhs.custom_attributes(), rhs.etag(),
                  rhs.event_types(), rhs.kind(), rhs.object_name_prefix(),
                  rhs.payload_format(), rhs.self_link(), rhs.topic());
}

inline bool operator<(NotificationMetadata const& lhs,
                      NotificationMetadata const& rhs) {
  return std::tie(lhs.id(), lhs.custom_attributes(), lhs.etag(),
                  lhs.event_types(), lhs.kind(), lhs.object_name_prefix(),
                  lhs.payload_format(), lhs.self_link(), lhs.topic()) <
         std::tie(rhs.id(), rhs.custom_attributes(), rhs.etag(),
                  rhs.event_types(), rhs.kind(), rhs.object_name_prefix(),
                  rhs.payload_format(), rhs.self_link(), rhs.topic());
}

inline bool operator!=(NotificationMetadata const& lhs,
                       NotificationMetadata const& rhs) {
  return std::rel_ops::operator!=(lhs, rhs);
}

inline bool operator>(NotificationMetadata const& lhs,
                      NotificationMetadata const& rhs) {
  return std::rel_ops::operator>(lhs, rhs);
}

inline bool operator<=(NotificationMetadata const& lhs,
                       NotificationMetadata const& rhs) {
  return std::rel_ops::operator<=(lhs, rhs);
}

inline bool operator>=(NotificationMetadata const& lhs,
                       NotificationMetadata const& rhs) {
  return std::rel_ops::operator>=(lhs, rhs);
}

std::ostream& operator<<(std::ostream& os, NotificationMetadata const& rhs);

}  // namespace STORAGE_CLIENT_NS
}  // namespace storage
}  // namespace cloud
}  // namespace google

#endif  // GOOGLE_CLOUD_CPP_GOOGLE_CLOUD_STORAGE_NOTIFICATION_METADATA_H