[Sync] Move //sync to //components/sync.

sync/internal_api/public/processor_entity_tracker.h

-// Copyright 2014 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 SYNC_INTERNAL_API_PUBLIC_PROCESSOR_ENTITY_TRACKER_H_
-#define SYNC_INTERNAL_API_PUBLIC_PROCESSOR_ENTITY_TRACKER_H_
-
-#include <stdint.h>
-
-#include <memory>
-#include <string>
-
-#include "base/time/time.h"
-#include "sync/api/entity_data.h"
-#include "sync/base/sync_export.h"
-#include "sync/protocol/entity_metadata.pb.h"
-
-namespace syncer_v2 {
-struct CommitRequestData;
-struct CommitResponseData;
-struct UpdateResponseData;
-
-// This class is used by the SharedModelTypeProcessor to track the state of each
-// entity with its type. It can be considered a helper class internal to the
-// processor. It manages the metadata for its entity and caches entity data
-// upon a local change until commit confirmation is received.
-class SYNC_EXPORT ProcessorEntityTracker {
- public:
-  // Construct an instance representing a new locally-created item.
-  static std::unique_ptr<ProcessorEntityTracker> CreateNew(
-      const std::string& client_tag,
-      const std::string& client_tag_hash,
-      const std::string& id,
-      base::Time creation_time);
-
-  // Construct an instance representing an item loaded from storage on init.
-  // This method swaps out the contents of |metadata|.
-  static std::unique_ptr<ProcessorEntityTracker> CreateFromMetadata(
-      const std::string& client_tag,
-      sync_pb::EntityMetadata* metadata);
-
-  ~ProcessorEntityTracker();
-
-  const std::string& client_tag() const { return client_tag_; }
-  const sync_pb::EntityMetadata& metadata() const { return metadata_; }
-  const EntityDataPtr& commit_data() const { return commit_data_; }
-
-  // Returns true if this data is out of sync with the server.
-  // A commit may or may not be in progress at this time.
-  bool IsUnsynced() const;
-
-  // Returns true if this data is out of sync with the sync thread.
-  //
-  // There may or may not be a commit in progress for this item, but there's
-  // definitely no commit in progress for this (most up to date) version of
-  // this item.
-  bool RequiresCommitRequest() const;
-
-  // Whether commit data is needed to be cached before a commit request can be
-  // created. Note that deletions do not require cached data.
-  bool RequiresCommitData() const;
-
-  // Whether it's safe to clear the metadata for this entity. This means that
-  // the entity is deleted and either knowledge of this entity has never left
-  // this client or it is up to date with the server.
-  bool CanClearMetadata() const;
-
-  // Returns true if the specified update version does not contain new data.
-  bool UpdateIsReflection(int64_t update_version) const;
-
-  // Records that an update from the server was received but ignores its data.
-  void RecordIgnoredUpdate(const UpdateResponseData& response_data);
-
-  // Records an update from the server assuming its data is the new data for
-  // this entity.
-  void RecordAcceptedUpdate(const UpdateResponseData& response_data);
-
-  // Squashes a pending commit with an update from the server.
-  void RecordForcedUpdate(const UpdateResponseData& response_data);
-
-  // Applies a local change to this item.
-  void MakeLocalChange(std::unique_ptr<EntityData> data);
-
-  // Applies a local deletion to this item.
-  void Delete();
-
-  // Initializes a message representing this item's uncommitted state
-  // and assumes that it is forwarded to the sync engine for commiting.
-  void InitializeCommitRequestData(CommitRequestData* request);
-
-  // Receives a successful commit response.
-  //
-  // Successful commit responses can overwrite an item's ID.
-  //
-  // Note that the receipt of a successful commit response does not necessarily
-  // unset IsUnsynced().  If many local changes occur in quick succession, it's
-  // possible that the committed item was already out of date by the time it
-  // reached the server.
-  void ReceiveCommitResponse(const CommitResponseData& data);
-
-  // Clears any in-memory sync state associated with outstanding commits.
-  void ClearTransientSyncState();
-
-  // Takes the passed commit data and caches it in the instance.
-  // The data is swapped from the input struct without copying.
-  void CacheCommitData(EntityData* data);
-
-  // Caches the a copy of |data_ptr|, which doesn't copy the data itself.
-  void CacheCommitData(const EntityDataPtr& data_ptr);
-
-  // Check if the instance has cached commit data.
-  bool HasCommitData() const;
-
-  // Check whether |data| matches the stored specifics hash.
-  bool MatchesData(const EntityData& data) const;
-
-  // Check whether |data| matches the stored base (shared between client and
-  // server) specifics hash.
-  bool MatchesBaseData(const EntityData& data) const;
-
-  // Increment sequence number in the metadata. This will also update the
-  // base_specifics_hash if the entity was not already unsynced.
-  void IncrementSequenceNumber();
-
- private:
-  friend class ProcessorEntityTrackerTest;
-
-  // The constructor swaps the data from the passed metadata.
-  ProcessorEntityTracker(const std::string& client_tag,
-                         sync_pb::EntityMetadata* metadata);
-
-  // Check whether |specifics| matches the stored specifics_hash.
-  bool MatchesSpecificsHash(const sync_pb::EntitySpecifics& specifics) const;
-
-  // Update hash string for EntitySpecifics in the metadata.
-  void UpdateSpecificsHash(const sync_pb::EntitySpecifics& specifics);
-
-  // Client tag. Should always be available.
-  std::string client_tag_;
-
-  // Serializable Sync metadata.
-  sync_pb::EntityMetadata metadata_;
-
-  // Sync data that exists for items being committed only.
-  // The data is reset once commit confirmation is received.
-  EntityDataPtr commit_data_;
-
-  // The sequence number of the last item sent to the sync thread.
-  int64_t commit_requested_sequence_number_;
-};
-
-}  // namespace syncer_v2
-
-#endif  // SYNC_INTERNAL_API_PUBLIC_PROCESSOR_ENTITY_TRACKER_H_