#pragma once

#include "envoy/api/api.h"

#include "envoy/config/core/v3/config_source.pb.h"

#include "envoy/config/subscription.h"

#include "envoy/config/subscription_factory.h"

#include "envoy/event/dispatcher.h"

#include "envoy/filesystem/filesystem.h"

#include "envoy/protobuf/message_validator.h"

#include "source/common/common/logger.h"

#include "source/common/config/watched_directory.h"

namespace Envoy {

namespace Config {

envoy::config::core::v3::PathConfigSource makePathConfigSource(const std::string& path);

/**

 * Filesystem inotify implementation of the API Subscription interface. This allows the API to be

 * consumed on filesystem changes to files containing the JSON canonical representation of

 * lists of xDS resources.

 */

class FilesystemSubscriptionImpl : public Config::Subscription,

                                   protected Logger::Loggable<Logger::Id::config> {

public:

  FilesystemSubscriptionImpl(Event::Dispatcher& dispatcher,

                             const envoy::config::core::v3::PathConfigSource& path_config_source,

                             SubscriptionCallbacks& callbacks,

                             OpaqueResourceDecoderSharedPtr resource_decoder,

                             SubscriptionStats stats,

                             ProtobufMessage::ValidationVisitor& validation_visitor, Api::Api& api);

  // Config::Subscription

  // We report all discovered resources in the watched file, so the resource names arguments are

  // unused, and updateResourceInterest is a no-op (other than updating a stat).

  void start(const absl::flat_hash_set<std::string>&) override;

  void updateResourceInterest(const absl::flat_hash_set<std::string>&) override;

protected:

  virtual std::string refreshInternal(ProtobufTypes::MessagePtr* config_update);

  void refresh();

  void configRejected(const EnvoyException& e, const std::string& message);

  bool started_{};

  const std::string path_;

  std::unique_ptr<Filesystem::Watcher> file_watcher_;

  WatchedDirectoryPtr directory_watcher_;

  SubscriptionCallbacks& callbacks_;

  OpaqueResourceDecoderSharedPtr resource_decoder_;

  SubscriptionStats stats_;

  Api::Api& api_;

  ProtobufMessage::ValidationVisitor& validation_visitor_;

};

// Currently a FilesystemSubscriptionImpl subclass, but this will need to change when we support

// non-inline collection resources.

class FilesystemCollectionSubscriptionImpl : public FilesystemSubscriptionImpl {

public:

  FilesystemCollectionSubscriptionImpl(

      Event::Dispatcher& dispatcher,

      const envoy::config::core::v3::PathConfigSource& path_config_source,

      SubscriptionCallbacks& callbacks, OpaqueResourceDecoderSharedPtr resource_decoder,

      SubscriptionStats stats, ProtobufMessage::ValidationVisitor& validation_visitor,

      Api::Api& api);

  std::string refreshInternal(ProtobufTypes::MessagePtr* config_update) override;

};

class FilesystemSubscriptionFactory : public ConfigSubscriptionFactory {

public:

};

class FilesystemCollectionSubscriptionFactory : public ConfigSubscriptionFactory {

public:

};

} // namespace Config

} // namespace Envoy