// Copyright 2018 The Chromium Authors
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#ifndef COMPONENTS_SEND_TAB_TO_SELF_SEND_TAB_TO_SELF_BRIDGE_H_
#define COMPONENTS_SEND_TAB_TO_SELF_SEND_TAB_TO_SELF_BRIDGE_H_

#include <functional>
#include <memory>
#include <optional>
#include <string>
#include <string_view>
#include <vector>

#include "base/containers/flat_map.h"
#include "base/containers/span.h"
#include "base/memory/raw_ptr.h"
#include "base/memory/weak_ptr.h"
#include "base/scoped_observation.h"
#include "base/time/time.h"
#include "components/history/core/browser/history_service.h"
#include "components/history/core/browser/history_service_observer.h"
#include "components/prefs/pref_service.h"
#include "components/send_tab_to_self/page_context.h"
#include "components/send_tab_to_self/send_tab_to_self_entry.h"
#include "components/send_tab_to_self/send_tab_to_self_model.h"
#include "components/sync/base/data_type.h"
#include "components/sync/model/data_type_store.h"
#include "components/sync/model/data_type_sync_bridge.h"
#include "components/sync_device_info/device_info_tracker.h"

namespace syncer {
class DataTypeLocalChangeProcessor;
}  // namespace syncer

namespace base {
class Clock;
}  // namespace base

namespace sync_sessions {
class SessionSyncService;
}  // namespace sync_sessions

namespace send_tab_to_self {

class SendTabToSelfCommitTracker;
struct TargetDeviceInfo;

// Interface for a persistence layer for send tab to self.
// All interface methods have to be called on main thread.
class SendTabToSelfBridge : public syncer::DataTypeSyncBridge,
                            public SendTabToSelfModel,
                            public history::HistoryServiceObserver {
 public:
  using SendTabToSelfEntries =
      std::map<std::string, std::unique_ptr<SendTabToSelfEntry>, std::less<>>;

  // The caller should ensure that all raw pointers are not null and will
  // outlive this object. This is not guaranteed by this class.
  SendTabToSelfBridge(
      std::unique_ptr<syncer::DataTypeLocalChangeProcessor> change_processor,
      base::Clock* clock,
      syncer::OnceDataTypeStoreFactory create_store_callback,
      history::HistoryService* history_service,
      syncer::DeviceInfoTracker* device_info_tracker,
      sync_sessions::SessionSyncService* session_sync_service,
      PrefService* pref_service);

  SendTabToSelfBridge(const SendTabToSelfBridge&) = delete;
  SendTabToSelfBridge& operator=(const SendTabToSelfBridge&) = delete;

  ~SendTabToSelfBridge() override;

  // syncer::DataTypeSyncBridge overrides.
  std::optional<syncer::ModelError> MergeFullSyncData(
      std::unique_ptr<syncer::MetadataChangeList> metadata_change_list,
      syncer::EntityChangeList entity_data) override;
  std::optional<syncer::ModelError> ApplyIncrementalSyncChanges(
      std::unique_ptr<syncer::MetadataChangeList> metadata_change_list,
      syncer::EntityChangeList entity_changes) override;
  std::unique_ptr<syncer::DataBatch> GetDataForCommit(
      StorageKeyList storage_keys) override;
  std::unique_ptr<syncer::DataBatch> GetAllDataForDebugging() override;
  std::string GetClientTag(
      const syncer::EntityData& entity_data) const override;
  std::string GetStorageKey(
      const syncer::EntityData& entity_data) const override;
  sync_pb::EntitySpecifics TrimAllSupportedFieldsFromRemoteSpecifics(
      const sync_pb::EntitySpecifics& entity_specifics) const override;
  bool IsEntityDataValid(const syncer::EntityData& entity_data) const override;
  void ApplyDisableSyncChanges(std::unique_ptr<syncer::MetadataChangeList>
                                   delete_metadata_change_list) override;
  void OnCommitAttemptErrors(
      const syncer::FailedCommitResponseDataList& error_response_list) override;
  CommitAttemptFailedBehavior OnCommitAttemptFailed(
      syncer::SyncCommitError error) override;

  // SendTabToSelfModel overrides.
  std::vector<std::string> GetAllGuids() const override;
  const SendTabToSelfEntry* GetEntryByGUID(
      std::string_view guid) const override;
  std::vector<const SendTabToSelfEntry*>
  GetUnopenedEntriesTargetedToLocalDevice() const override;
  std::vector<const SendTabToSelfEntry*> GetOpenedEntriesTargetedToLocalDevice()
      const override;
  const SendTabToSelfEntry* SendEntry(
      const GURL& url,
      const std::string& title,
      const std::string& target_device_cache_guid,
      const PageContext& context,
      NavigationHistory navigation_history,
      base::OnceCallback<void(SendTabToSelfResult)> commit_confirmation,
      ShareEntryPoint entry_point) override;
  void DismissEntry(std::string_view guid) override;
  void MarkEntryOpened(std::string_view guid) override;
  void MarkEntryActivated(std::string_view guid,
                          ShareActivatedEntryPoint entry_point) override;
  bool IsReady() override;
  bool HasValidTargetDevice() override;
  std::vector<TargetDeviceInfo> GetTargetDeviceInfoSortedList() override;
  std::optional<TargetDeviceInfo> GetTargetDeviceInfo(
      std::string_view cache_guid) override;

  // history::HistoryServiceObserver:
  void OnHistoryDeletions(history::HistoryService* history_service,
                          const history::DeletionInfo& deletion_info) override;

  // For testing only.
  static std::unique_ptr<syncer::DataTypeStore> DestroyAndStealStoreForTest(
      std::unique_ptr<SendTabToSelfBridge> bridge);
  void SetLocalDeviceNameForTest(const std::string& local_device_name);

 private:
  // Notify all observers of any added |new_entries| when they are added the the
  // model via sync.
  void NotifyRemoteSendTabToSelfEntryAdded(
      base::span<const SendTabToSelfEntry* const> new_entries);

  // Notify all observers when the entries with |guids| have been removed from
  // the model via sync or via history deletion.
  void NotifyRemoteSendTabToSelfEntryDeleted(
      base::span<const std::string> guids);

  // Notify all observers when any new or existing |opened_entries| have been
  // marked as opened in the model via sync.
  void NotifyRemoteSendTabToSelfEntryOpened(
      base::span<const SendTabToSelfEntry* const> opened_entries);

  // Methods used as callbacks given to DataTypeStore.
  void OnStoreCreated(const std::optional<syncer::ModelError>& error,
                      std::unique_ptr<syncer::DataTypeStore> store);
  void OnReadAllData(std::unique_ptr<SendTabToSelfEntries> initial_entries,
                     const std::optional<syncer::ModelError>& error);
  void OnReadAllMetadata(const std::optional<syncer::ModelError>& error,
                         std::unique_ptr<syncer::MetadataBatch> metadata_batch);
  void OnCommit(const std::optional<syncer::ModelError>& error);

  // Persists the changes in the given aggregators
  void Commit(std::unique_ptr<syncer::DataTypeStore::WriteBatch> batch);

  // Returns a specific entry for editing. Returns null if the entry does not
  // exist.
  SendTabToSelfEntry* GetMutableEntryByGUID(std::string_view guid) const;

  bool IsTargetedToLocalDevice(const SendTabToSelfEntry& entry) const;

  // Returns the DeviceInfo for the local device, or nullptr if not available.
  const syncer::DeviceInfo* GetLocalDeviceInfo() const;

  // Returns the display name of the local device.
  std::string GetLocalDeviceName() const;

  // Returns true if the device should be included in the target list.
  bool ShouldIncludeDevice(const syncer::DeviceInfo& device) const;

  // Delete expired entries.
  void DoGarbageCollection();

  // Remove entry with |guid| from entries, but doesn't call Commit on provided
  // |batch|. This allows multiple for deletions without duplicate batch calls.
  void DeleteEntryWithBatch(std::string_view guid,
                            syncer::DataTypeStore::WriteBatch* batch);

  // Delete all of the entries that match the URLs provided.
  void DeleteEntries(const std::vector<GURL>& urls);

  void DeleteAllEntries();

  void EraseEntryInBatch(std::string_view guid,
                         syncer::DataTypeStore::WriteBatch* batch);

  void MarkEntryOpenedImpl(std::string_view guid, base::Time opened_time);

  void MarkEntryActivatedImpl(std::string_view guid,
                              ShareActivatedEntryPoint entry_point,
                              base::Time activated_time);

  // Helper to commit a local mutation of an entry to the store and processor.
  void CommitLocalEntryMutation(const SendTabToSelfEntry& entry);

  // |entries_| is keyed by GUIDs.
  SendTabToSelfEntries entries_;

  std::unique_ptr<SendTabToSelfCommitTracker> commit_tracker_;

  // Stores guids of entries that have been opened from a layer other than
  // SendTabToSelfModel, along with the time the open was requested. Once
  // the bridge receives the respective entries, they will be marked opened
  // using the stored timestamp. Entries are in-memory only and will be lost
  // on browser restart.
  base::flat_map<std::string, base::Time, std::less<>> unknown_opened_entries_;
  // Stores guids of entries that have been activated from a layer other than
  // SendTabToSelfModel, along with the time and entry point when the activation
  // was requested. Entries are in-memory only and will be lost on browser
  // restart.
  base::flat_map<std::string,
                 std::pair<base::Time, ShareActivatedEntryPoint>,
                 std::less<>>
      unknown_activated_entries_;

  // |clock_| isn't owned.
  const raw_ptr<const base::Clock> clock_;

  // |history_service_| isn't owned.
  const raw_ptr<history::HistoryService> history_service_;

  // |device_info_tracker_| isn't owned.
  const raw_ptr<syncer::DeviceInfoTracker> device_info_tracker_;

  // `session_sync_service_` isn't owned.
  const raw_ptr<sync_sessions::SessionSyncService> session_sync_service_;

  // `pref_service_` isn't owned.
  const raw_ptr<PrefService> pref_service_;

  // The name of this local device, set only for testing.
  std::optional<std::string> local_device_name_for_testing_;

  // In charge of actually persisting changes to disk, or loading previous data.
  std::unique_ptr<syncer::DataTypeStore> store_;

  // The string identifier of the most recently used entry used for
  // deduplication.
  std::string mru_entry_guid_;

  base::ScopedObservation<history::HistoryService, HistoryServiceObserver>
      history_service_observation_{this};

  base::WeakPtrFactory<SendTabToSelfBridge> weak_ptr_factory_{this};
};

}  // namespace send_tab_to_self

#endif  // COMPONENTS_SEND_TAB_TO_SELF_SEND_TAB_TO_SELF_BRIDGE_H_