File indexing completed on 2024-06-16 04:50:14

 /*
     SPDX-FileCopyrightText: 2007 Tobias Koenig <tokoe@kde.org>
 
     SPDX-License-Identifier: LGPL-2.0-or-later
 */
 
 #pragma once
 
 #include "akonadicore_export.h"
 #include "item.h"
 #include "job.h"
 
 #include <QDateTime>
 
 namespace Akonadi
 {
 class Collection;
 class ItemSyncPrivate;
 
 /**
  * @short Syncs between items known to a client (usually a resource) and the Akonadi storage.
  *
  * Remote Id must only be set by the resource storing the item, other clients
  * should leave it empty, since the resource responsible for the target collection
  * will be notified about the addition and then create a suitable remote Id.
  *
  * There are two different forms of ItemSync usage:
  * - Full-Sync: meaning the client provides all valid items, i.e. any item not
  *   part of the list but currently stored in Akonadi will be removed
  * - Incremental-Sync: meaning the client provides two lists, one for items which
  *   are new or modified and one for items which should be removed. Any item not
  *   part of either list but currently stored in Akonadi will not be changed.
  *
  * @note This is provided for convenience to implement "save all" like behavior,
  *       however it is strongly recommended to use single item jobs whenever
  *       possible, e.g. ItemCreateJob, ItemModifyJob and ItemDeleteJob
  *
  * @author Tobias Koenig <tokoe@kde.org>
  */
 class AKONADICORE_EXPORT ItemSync : public Job
 {
     Q_OBJECT
 
 public:
     enum MergeMode {
         RIDMerge,
         GIDMerge,
     };
 
     /**
      * Creates a new item synchronizer.
      *
      * @param collection The collection we are syncing.
      * @param timestamp Optional timestamp of itemsync start. Will be used to detect local changes that happen
                         while the ItemSync is running.
      * @param parent The parent object.
      */
     explicit ItemSync(const Collection &collection, const QDateTime &timestamp = {}, QObject *parent = nullptr);
 
     /**
      * Destroys the item synchronizer.
      */
     ~ItemSync() override;
 
     /**
      * Sets the full item list for the collection.
      *
      * Usually the result of a full item listing.
      *
      * @warning If the client using this is a resource, all items must have
      *          a valid remote identifier.
      *
      * @param items A list of items.
      */
     void setFullSyncItems(const Item::List &items);
 
     /**
      * Set the amount of items which you are going to return in total
      * by using the setFullSyncItems()/setIncrementalSyncItems() methods.
      *
      * @warning By default the item sync will automatically end once
      * sufficient items have been provided.
      * To disable this use setDisableAutomaticDeliveryDone
      *
      * @see setDisableAutomaticDeliveryDone
      * @param amount The amount of items in total.
      */
     void setTotalItems(int amount);
 
     /**
       Enable item streaming. Item streaming means that the items delivered by setXItems() calls
       are delivered in chunks and you manually indicate when all items have been delivered
       by calling deliveryDone().
       @param enable @c true to enable item streaming
     */
     void setStreamingEnabled(bool enable);
 
     /**
       Notify ItemSync that all remote items have been delivered.
       Only call this in streaming mode.
     */
     void deliveryDone();
 
     /**
      * Sets the item lists for incrementally syncing the collection.
      *
      * Usually the result of an incremental remote item listing.
      *
      * @warning If the client using this is a resource, all items must have
      *          a valid remote identifier.
      *
      * @param changedItems A list of items added or changed by the client.
      * @param removedItems A list of items deleted by the client.
      */
     void setIncrementalSyncItems(const Item::List &changedItems, const Item::List &removedItems);
 
     /**
      * Aborts the sync process and rolls back all not yet committed transactions.
      * Use this if an external error occurred during the sync process (such as the
      * user canceling it).
      * @since 4.5
      */
     void rollback();
 
     /**
      * Transaction mode used by ItemSync.
      * @since 4.6
      */
     enum TransactionMode {
         SingleTransaction, ///< Use a single transaction for the entire sync process (default), provides maximum consistency ("all or nothing") and best
                            ///< performance
         MultipleTransactions, ///< Use one transaction per chunk of delivered items, good compromise between the other two when using streaming
         NoTransaction ///< Use no transaction at all, provides highest responsiveness (might therefore feel faster even when actually taking slightly longer),
                       ///< no consistency guaranteed (can fail anywhere in the sync process)
     };
 
     /**
      * Set the transaction mode to use for this sync.
      * @note You must call this method before starting the sync, changes afterwards lead to undefined results.
      * @param mode the transaction mode to use
      * @since 4.6
      */
     void setTransactionMode(TransactionMode mode);
 
     /**
      * Minimum number of items required to start processing in streaming mode.
      * When MultipleTransactions is used, one transaction per batch will be created.
      *
      * @see setBatchSize()
      * @since 4.14
      */
     [[nodiscard]] int batchSize() const;
 
     /**
      * Set the batch size.
      *
      * The default is 10.
      *
      * @note You must call this method before starting the sync, changes afterwards lead to undefined results.
      * @see batchSize()
      * @since 4.14
      */
     void setBatchSize(int);
 
     /**
      * Disables the automatic completion of the item sync,
      * based on the number of delivered items.
      *
      * This ensures that the item sync only finishes once deliveryDone()
      * is called, while still making it possible to use the progress
      * reporting of the ItemSync.
      *
      * @note You must call this method before starting the sync, changes afterwards lead to undefined results.
      * @see setTotalItems
      * @since 4.14
      */
     void setDisableAutomaticDeliveryDone(bool disable);
 
     /**
      * Returns current merge mode
      *
      * @see setMergeMode()
      * @since 5.1
      */
     [[nodiscard]] MergeMode mergeMode() const;
 
     /**
      * Set what merge method should be used for next ItemSync run
      *
      * By default ItemSync uses RIDMerge method.
      *
      * See ItemCreateJob for details on Item merging.
      *
      * @note You must call this method before starting the sync, changes afterwards lead to undefined results.
      * @see mergeMode
      * @since 4.14.11
      */
     void setMergeMode(MergeMode mergeMode);
 
 Q_SIGNALS:
     /**
      * Signals the resource that new items can be delivered.
      * @param remainingBatchSize the number of items required to complete the batch (typically the same as batchSize())
      *
      * @since 4.14
      */
     void readyForNextBatch(int remainingBatchSize);
 
     /**
      * @internal
      * Emitted whenever a transaction is committed. This is for testing only.
      *
      * @since 4.14
      */
     void transactionCommitted();
 
 protected:
     void doStart() override;
     void slotResult(KJob *job) override;
 
 private:
     /// @cond PRIVATE
     Q_DECLARE_PRIVATE(ItemSync)
 
     Q_PRIVATE_SLOT(d_func(), void slotLocalListDone(KJob *))
     Q_PRIVATE_SLOT(d_func(), void slotTransactionResult(KJob *))
     Q_PRIVATE_SLOT(d_func(), void slotItemsReceived(const Akonadi::Item::List &))
     /// @endcond
 };
 
 }