File indexing completed on 2024-06-16 04:50:15

 /*
     SPDX-FileCopyrightText: 2006-2007 Volker Krause <vkrause@kde.org>
 
     SPDX-License-Identifier: LGPL-2.0-or-later
 */
 
 #pragma once
 
 #include "akonadicore_export.h"
 #include "collection.h"
 #include "item.h"
 #include "relation.h"
 #include "tag.h"
 
 #include <QObject>
 
 #include <memory>
 
 namespace Akonadi
 {
 class CollectionFetchScope;
 class CollectionStatistics;
 class Item;
 class ItemFetchScope;
 class MonitorPrivate;
 class Session;
 class TagFetchScope;
 class NotificationSubscriber;
 class ChangeNotification;
 
 namespace Protocol
 {
 class Command;
 }
 
 /**
  * @short Monitors an item or collection for changes.
  *
  * The Monitor emits signals if some of these objects are changed or
  * removed or new ones are added to the Akonadi storage.
  *
  * There are various ways to filter these notifications. There are three types of filter
  * evaluation:
  * - (-) removal-only filter, ie. if the filter matches the notification is dropped,
  *   if not filter evaluation continues with the next one
  * - (+) pass-exit filter, ie. if the filter matches the notification is delivered,
  *   if not evaluation is continued
  * - (f) final filter, ie. evaluation ends here if the corresponding filter criteria is set,
  *   the notification is delivered depending on the result, evaluation is only continued
  *   if no filter criteria is defined
  *
  * The following filter are available, listed in evaluation order:
  * (1) ignored sessions (-)
  * (2) monitor everything (+)
  * (3a) resource and mimetype filters (f) (items only)
  * (3b) resource filters (f) (collections only)
  * (4) item is monitored (+)
  * (5) collection is monitored (+)
  *
  * Optionally, the changed objects can be fetched automatically from the server.
  * To enable this, see itemFetchScope() and collectionFetchScope().
  *
  * Note that as a consequence of rule 3a, it is not possible to monitor (more than zero resources
  * OR more than zero mimetypes) AND more than zero collections.
  *
  * @todo Distinguish between monitoring collection properties and collection content.
  * @todo Special case for collection content counts changed
  *
  * @author Volker Krause <vkrause@kde.org>
  */
 class AKONADICORE_EXPORT Monitor : public QObject
 {
     Q_OBJECT
 
 public:
     enum Type {
         /**
          * @internal This must be kept in sync with Akonadi::NotificationMessageV2::Type
          */
         Collections = 1,
         Items,
         Tags,
         Relations,
         /**
          * Listen to subscription changes of other Monitors connected to Akonadi.
          * This is only for debugging purposes and should not be used in real
          * applications.
          * @since 5.4
          */
         Subscribers,
         /**
          * Listens to all notifications being emitted by the server and provides
          * additional information about them. This is only for debugging purposes
          * and should not be used in real applications.
          *
          * @note Enabling monitoring this type has performance impact on the
          * Akonadi Server.
          *
          * @since 5.4
          */
         Notifications
     };
 
     /**
      * Creates a new monitor.
      *
      * @param parent The parent object.
      */
     explicit Monitor(QObject *parent = nullptr);
 
     /**
      * Destroys the monitor.
      */
     ~Monitor() override;
 
     /**
      * Sets whether the specified collection shall be monitored for changes. If
      * monitoring is turned on for the collection, all notifications for items
      * in that collection will be emitted, and its child collections will also
      * be monitored. Note that move notifications will be emitted if either one
      * of the collections involved is being monitored.
      *
      * Note that if a session is being ignored, this takes precedence over
      * setCollectionMonitored() on that session.
      *
      * @param collection The collection to monitor.
      *                   If this collection is Collection::root(), all collections
      *                   in the Akonadi storage will be monitored.
      * @param monitored Whether to monitor the collection.
      */
     void setCollectionMonitored(const Collection &collection, bool monitored = true);
 
     /**
      * Sets whether the specified item shall be monitored for changes.
      *
      * Note that if a session is being ignored, this takes precedence over
      * setItemMonitored() on that session.
      *
      * @param item The item to monitor.
      * @param monitored Whether to monitor the item.
      */
     void setItemMonitored(const Item &item, bool monitored = true);
 
     /**
      * Sets whether the specified resource shall be monitored for changes. If
      * monitoring is turned on for the resource, all notifications for
      * collections and items in that resource will be emitted.
      *
      * Note that if a session is being ignored, this takes precedence over
      * setResourceMonitored() on that session.
      *
      * @param resource The resource identifier.
      * @param monitored Whether to monitor the resource.
      */
     void setResourceMonitored(const QByteArray &resource, bool monitored = true);
 
     /**
      * Sets whether items of the specified mime type shall be monitored for changes.
      * If monitoring is turned on for the mime type, all notifications for items
      * matching that mime type will be emitted, but notifications for collections
      * matching that mime type will only be emitted if this is otherwise specified,
      * for example by setCollectionMonitored().
      *
      * Note that if a session is being ignored, this takes precedence over
      * setMimeTypeMonitored() on that session.
      *
      * @param mimetype The mime type to monitor.
      * @param monitored Whether to monitor the mime type.
      */
     void setMimeTypeMonitored(const QString &mimetype, bool monitored = true);
 
     /**
      * Sets whether the specified tag shall be monitored for changes.
      *
      * Same rules as for item monitoring apply.
      *
      * @param tag Tag to monitor.
      * @param monitored Whether to monitor the tag.
      * @since 4.13
      */
     void setTagMonitored(const Tag &tag, bool monitored = true);
 
     /**
      * Sets whether given type (Collection, Item, Tag should be monitored).
      *
      * By default all types are monitored, but once you change one, you have
      * to explicitly enable all other types you want to monitor.
      *
      * @param type Type to monitor.
      * @param monitored Whether to monitor the type
      * @since 4.13
      */
     void setTypeMonitored(Type type, bool monitored = true);
 
     /**
      * Sets whether all items shall be monitored.
      * @param monitored sets all items as monitored if set as @c true
      * Note that if a session is being ignored, this takes precedence over
      * setAllMonitored() on that session.
      */
     void setAllMonitored(bool monitored = true);
 
     void setExclusive(bool exclusive = true);
     [[nodiscard]] bool exclusive() const;
 
     /**
      * Ignores all change notifications caused by the given session. This
      * overrides all other settings on this session.
      *
      * @param session The session you want to ignore.
      */
     void ignoreSession(Session *session);
 
     /**
      * Enables automatic fetching of changed collections from the Akonadi storage.
      *
      * @param enable @c true enables automatic fetching, @c false disables automatic fetching.
      */
     void fetchCollection(bool enable);
 
     /**
      * Enables automatic fetching of changed collection statistics information from
      * the Akonadi storage.
      *
      * @param enable @c true to enables automatic fetching, @c false disables automatic fetching.
      */
     void fetchCollectionStatistics(bool enable);
 
     /**
      * Sets the item fetch scope.
      *
      * Controls how much of an item's data is fetched from the server, e.g.
      * whether to fetch the full item payload or only meta data.
      *
      * @param fetchScope The new scope for item fetch operations.
      *
      * @see itemFetchScope()
      */
     void setItemFetchScope(const ItemFetchScope &fetchScope);
 
     /**
      * Instructs the monitor to fetch only those parts that were changed and
      * were requested in the fetch scope.
      *
      * This is taken in account only for item modifications.
      * Example usage:
      * @code
      *   monitor->itemFetchScope().fetchFullPayload( true );
      *   monitor->fetchChangedOnly(true);
      * @endcode
      *
      * In the example if an item was changed, but its payload was not, the full
      * payload will not be retrieved.
      * If the item's payload was changed, the monitor retrieves the changed
      * payload as well.
      *
      * The default is to fetch everything requested.
      *
      * @since 4.8
      *
      * @param enable @c true to enable the feature, @c false means everything
      * that was requested will be fetched.
      */
     void fetchChangedOnly(bool enable);
 
     /**
      * Returns the item fetch scope.
      *
      * Since this returns a reference it can be used to conveniently modify the
      * current scope in-place, i.e. by calling a method on the returned reference
      * without storing it in a local variable. See the ItemFetchScope documentation
      * for an example.
      *
      * @return a reference to the current item fetch scope
      *
      * @see setItemFetchScope() for replacing the current item fetch scope
      */
     ItemFetchScope &itemFetchScope();
 
     /**
      * Sets the collection fetch scope.
      *
      * Controls which collections are monitored and how much of a collection's data
      * is fetched from the server.
      *
      * @param fetchScope The new scope for collection fetch operations.
      *
      * @see collectionFetchScope()
      * @since 4.4
      */
     void setCollectionFetchScope(const CollectionFetchScope &fetchScope);
 
     /**
      * Returns the collection fetch scope.
      *
      * Since this returns a reference it can be used to conveniently modify the
      * current scope in-place, i.e. by calling a method on the returned reference
      * without storing it in a local variable. See the CollectionFetchScope documentation
      * for an example.
      *
      * @return a reference to the current collection fetch scope
      *
      * @see setCollectionFetchScope() for replacing the current collection fetch scope
      * @since 4.4
      */
     CollectionFetchScope &collectionFetchScope();
 
     /**
      * Sets the tag fetch scope.
      *
      * Controls how much of an tag's data is fetched from the server.
      *
      * @param fetchScope The new scope for tag fetch operations.
      *
      * @see tagFetchScope()
      */
     void setTagFetchScope(const TagFetchScope &fetchScope);
 
     /**
      * Returns the tag fetch scope.
      *
      * Since this returns a reference it can be used to conveniently modify the
      * current scope in-place, i.e. by calling a method on the returned reference
      * without storing it in a local variable.
      *
      * @return a reference to the current tag fetch scope
      *
      * @see setTagFetchScope() for replacing the current tag fetch scope
      */
     TagFetchScope &tagFetchScope();
 
     /**
      * Returns the list of collections being monitored.
      *
      * @since 4.3
      */
     [[nodiscard]] Collection::List collectionsMonitored() const;
 
     /**
      * Returns the set of items being monitored.
      *
      * Faster version (at least on 32-bit systems) of itemsMonitored().
      *
      * @since 4.6
      */
     [[nodiscard]] QList<Item::Id> itemsMonitoredEx() const;
 
     /**
      * Returns the number of items being monitored.
      * Optimization.
      * @since 4.14.3
      */
     [[nodiscard]] int numItemsMonitored() const;
 
     /**
      * Returns the set of mimetypes being monitored.
      *
      * @since 4.3
      */
     [[nodiscard]] QStringList mimeTypesMonitored() const;
 
     /**
      * Returns the number of mimetypes being monitored.
      * Optimization.
      * @since 4.14.3
      */
     [[nodiscard]] int numMimeTypesMonitored() const;
 
     /**
      * Returns the set of tags being monitored.
      *
      * @since 4.13
      */
     [[nodiscard]] QList<Tag::Id> tagsMonitored() const;
 
     /**
      * Returns the set of types being monitored.
      *
      * @since 4.13
      */
     [[nodiscard]] QList<Type> typesMonitored() const;
 
     /**
      * Returns the set of identifiers for resources being monitored.
      *
      * @since 4.3
      */
     [[nodiscard]] QList<QByteArray> resourcesMonitored() const;
 
     /**
      * Returns the number of resources being monitored.
      * Optimization.
      * @since 4.14.3
      */
     [[nodiscard]] int numResourcesMonitored() const;
 
     /**
      * Returns true if everything is being monitored.
      *
      * @since 4.3
      */
     [[nodiscard]] bool isAllMonitored() const;
 
     /**
      * Sets the session used by the Monitor to communicate with the %Akonadi server.
      * If not set, the Akonadi::Session::defaultSession is used.
      * @param session the session to be set
      * @since 4.4
      */
     void setSession(Akonadi::Session *session);
 
     /**
      * Returns the Session used by the monitor to communicate with Akonadi.
      *
      * @since 4.4
      */
     [[nodiscard]] Session *session() const;
 
     /**
      * Allows to enable/disable collection move translation. If enabled (the default), move
      * notifications are automatically translated into add/remove notifications if the source/destination
      * is outside of the monitored collection hierarchy.
      * @param enabled enables collection move translation if set as @c true
      * @since 4.9
      */
     void setCollectionMoveTranslationEnabled(bool enabled);
 
 Q_SIGNALS:
     /**
      * This signal is emitted if a monitored item has changed, e.g. item parts have been modified.
      *
      * @param item The changed item.
      * @param partIdentifiers The identifiers of the item parts that has been changed.
      */
     void itemChanged(const Akonadi::Item &item, const QSet<QByteArray> &partIdentifiers);
 
     /**
      * This signal is emitted if flags of monitored items have changed.
      *
      * @param items Items that were changed
      * @param addedFlags Flags that have been added to each item in @p items
      * @param removedFlags Flags that have been removed from each item in @p items
      * @since 4.11
      */
     void itemsFlagsChanged(const Akonadi::Item::List &items, const QSet<QByteArray> &addedFlags, const QSet<QByteArray> &removedFlags);
 
     /**
      * This signal is emitted if tags of monitored items have changed.
      *
      * @param items Items that were changed
      * @param addedTags Tags that have been added to each item in @p items.
      * @param removedTags Tags that have been removed from each item in @p items
      * @since 4.13
      */
     void itemsTagsChanged(const Akonadi::Item::List &items, const QSet<Akonadi::Tag> &addedTags, const QSet<Akonadi::Tag> &removedTags);
 
     /**
      * This signal is emitted if relations of monitored items have changed.
      *
      * @param items Items that were changed
      * @param addedRelations Relations that have been added to each item in @p items.
      * @param removedRelations Relations that have been removed from each item in @p items
      * @since 4.15
      */
     void
     itemsRelationsChanged(const Akonadi::Item::List &items, const Akonadi::Relation::List &addedRelations, const Akonadi::Relation::List &removedRelations);
 
     /**
      * This signal is emitted if a monitored item has been moved between two collections
      *
      * @param item The moved item.
      * @param collectionSource The collection the item has been moved from.
      * @param collectionDestination The collection the item has been moved to.
      */
     void itemMoved(const Akonadi::Item &item, const Akonadi::Collection &collectionSource, const Akonadi::Collection &collectionDestination);
 
     /**
      * This is signal is emitted when multiple monitored items have been moved between two collections
      *
      * @param items Moved items
      * @param collectionSource The collection the items have been moved from.
      * @param collectionDestination The collection the items have been moved to.
      *
      * @since 4.11
      */
     void itemsMoved(const Akonadi::Item::List &items, const Akonadi::Collection &collectionSource, const Akonadi::Collection &collectionDestination);
 
     /**
      * This signal is emitted if an item has been added to a monitored collection in the Akonadi storage.
      *
      * @param item The new item.
      * @param collection The collection the item has been added to.
      */
     void itemAdded(const Akonadi::Item &item, const Akonadi::Collection &collection);
 
     /**
      * This signal is emitted if
      *   - a monitored item has been removed from the Akonadi storage
      * or
      *   - a item has been removed from a monitored collection.
      *
      * @param item The removed item.
      */
     void itemRemoved(const Akonadi::Item &item);
 
     /**
      * This signal is emitted if monitored items have been removed from Akonadi
      * storage of items have been removed from a monitored collection.
      *
      * @param items Removed items
      *
      * @since 4.11
      */
     void itemsRemoved(const Akonadi::Item::List &items);
 
     /**
      * This signal is emitted if a reference to an item is added to a virtual collection.
      * @param item The linked item.
      * @param collection The collection the item is linked to.
      *
      * @since 4.2
      */
     void itemLinked(const Akonadi::Item &item, const Akonadi::Collection &collection);
 
     /**
      * This signal is emitted if a reference to multiple items is added to a virtual collection
      *
      * @param items The linked items
      * @param collection The collections the items are linked to
      *
      * @since 4.11
      */
     void itemsLinked(const Akonadi::Item::List &items, const Akonadi::Collection &collection);
 
     /**
      * This signal is emitted if a reference to an item is removed from a virtual collection.
      * @param item The unlinked item.
      * @param collection The collection the item is unlinked from.
      *
      * @since 4.2
      */
     void itemUnlinked(const Akonadi::Item &item, const Akonadi::Collection &collection);
 
     /**
      * This signal is emitted if a reference to items is removed from a virtual collection
      *
      * @param items The unlinked items
      * @param collection The collections the items are unlinked from
      *
      * @since 4.11
      */
     void itemsUnlinked(const Akonadi::Item::List &items, const Akonadi::Collection &collection);
 
     /**
      * This signal is emitted if a new collection has been added to a monitored collection in the Akonadi storage.
      *
      * @param collection The new collection.
      * @param parent The parent collection.
      */
     void collectionAdded(const Akonadi::Collection &collection, const Akonadi::Collection &parent);
 
     /**
      * This signal is emitted if a monitored collection has been changed (properties or content).
      *
      * @param collection The changed collection.
      */
     void collectionChanged(const Akonadi::Collection &collection);
 
     /**
      * This signal is emitted if a monitored collection has been changed (properties or attributes).
      *
      * @param collection The changed collection.
      * @param attributeNames The names of the collection attributes that have been changed.
      *
      * @since 4.4
      */
     void collectionChanged(const Akonadi::Collection &collection, const QSet<QByteArray> &attributeNames);
 
     /**
      * This signals is emitted if a monitored collection has been moved.
      *
      * @param collection The moved collection.
      * @param source The previous parent collection.
      * @param destination The new parent collection.
      *
      * @since 4.4
      */
     void collectionMoved(const Akonadi::Collection &collection, const Akonadi::Collection &source, const Akonadi::Collection &destination);
 
     /**
      * This signal is emitted if a monitored collection has been removed from the Akonadi storage.
      *
      * @param collection The removed collection.
      */
     void collectionRemoved(const Akonadi::Collection &collection);
 
     /**
      * This signal is emitted if a collection has been subscribed to by the user.
      *  It will be emitted even for unmonitored collections as the check for whether to
      *  monitor it has not been applied yet.
      *
      * @param collection The subscribed collection
      * @param parent The parent collection of the subscribed collection.
      *
      * @since 4.6
      */
     void collectionSubscribed(const Akonadi::Collection &collection, const Akonadi::Collection &parent);
 
     /**
      * This signal is emitted if a user unsubscribes from a collection.
      *
      * @param collection The unsubscribed collection
      *
      * @since 4.6
      */
     void collectionUnsubscribed(const Akonadi::Collection &collection);
 
     /**
      * This signal is emitted if the statistics information of a monitored collection
      * has changed.
      *
      * @param id The collection identifier of the changed collection.
      * @param statistics The updated collection statistics, invalid if automatic
      *                   fetching of statistics changes is disabled.
      */
     void collectionStatisticsChanged(Akonadi::Collection::Id id, const Akonadi::CollectionStatistics &statistics);
 
     /**
      * This signal is emitted if a tag has been added to Akonadi storage.
      *
      * @param tag The added tag
      * @since 4.13
      */
     void tagAdded(const Akonadi::Tag &tag);
 
     /**
      * This signal is emitted if a monitored tag is changed on the server.
      *
      * @param tag The changed tag.
      * @since 4.13
      */
     void tagChanged(const Akonadi::Tag &tag);
 
     /**
      * This signal is emitted if a monitored tag is removed from the server storage.
      *
      * The monitor will also emit itemTagsChanged() signal for all monitored items
      * (if any) that were tagged by @p tag.
      *
      * @param tag The removed tag.
      * @since 4.13
      */
     void tagRemoved(const Akonadi::Tag &tag);
 
     /**
      * This signal is emitted if a relation has been added to Akonadi storage.
      *
      * The monitor will also emit itemRelationsChanged() signal for all monitored items
      * hat are affected by @p relation.
      *
      * @param relation The added relation
      * @since 4.13
      */
     void relationAdded(const Akonadi::Relation &relation);
 
     /**
      * This signal is emitted if a monitored relation is removed from the server storage.
      *
      * The monitor will also emit itemRelationsChanged() signal for all monitored items
      * that were affected by @p relation.
      *
      * @param relation The removed relation.
      * @since 4.13
      */
     void relationRemoved(const Akonadi::Relation &relation);
 
     /**
      * This signal is emitted when Subscribers are monitored and a new subscriber
      * subscribers to the server.
      *
      * @param subscriber The new subscriber
      * @since 5.4
      *
      * @note Monitoring for subscribers and listening to this signal only makes
      * sense if you want to globally debug Monitors. There is no reason to use
      * this in regular applications.
      */
     void notificationSubscriberAdded(const Akonadi::NotificationSubscriber &subscriber);
 
     /**
      * This signal is emitted when Subscribers are monitored and an existing
      * subscriber changes its subscription.
      *
      * @param subscriber The changed subscriber
      * @since 5.4
      *
      * @note Monitoring for subscribers and listening to this signal only makes
      * sense if you want to globally debug Monitors. There is no reason to use
      * this in regular applications.
      */
     void notificationSubscriberChanged(const Akonadi::NotificationSubscriber &subscriber);
 
     /**
      * This signal is emitted when Subscribers are monitored and an existing
      * subscriber unsubscribes from the server.
      *
      * @param subscriber The removed subscriber
      * @since 5.4
      *
      * @note Monitoring for subscribers and listening to this signal only makes
      * sense if you want to globally debug Monitors. There is no reason to use
      * this in regular applications.
      */
     void notificationSubscriberRemoved(const Akonadi::NotificationSubscriber &subscriber);
 
     /**
      * This signal is emitted when Notifications are monitored and the server emits
      * any change notification.
      *
      * @since 5.4
      *
      * @note Getting introspection into all change notifications only makes sense
      * if you want to globally debug Notifications. There is no reason to use
      * this in regular applications.
      */
     void debugNotification(const Akonadi::ChangeNotification &notification);
 
     /**
      * This signal is emitted if the Monitor starts or stops monitoring @p collection explicitly.
      * @param collection The collection
      * @param monitored Whether the collection is now being monitored or not.
      *
      * @since 4.3
      */
     void collectionMonitored(const Akonadi::Collection &collection, bool monitored);
 
     /**
      * This signal is emitted if the Monitor starts or stops monitoring @p item explicitly.
      * @param item The item
      * @param monitored Whether the item is now being monitored or not.
      *
      * @since 4.3
      */
     void itemMonitored(const Akonadi::Item &item, bool monitored);
 
     /**
      * This signal is emitted if the Monitor starts or stops monitoring the resource with the identifier @p identifier explicitly.
      * @param identifier The identifier of the resource.
      * @param monitored Whether the resource is now being monitored or not.
      *
      * @since 4.3
      */
     void resourceMonitored(const QByteArray &identifier, bool monitored);
 
     /**
      * This signal is emitted if the Monitor starts or stops monitoring @p mimeType explicitly.
      * @param mimeType The mimeType.
      * @param monitored Whether the mimeType is now being monitored or not.
      *
      * @since 4.3
      */
     void mimeTypeMonitored(const QString &mimeType, bool monitored);
 
     /**
      * This signal is emitted if the Monitor starts or stops monitoring everything.
      * @param monitored Whether everything is now being monitored or not.
      *
      * @since 4.3
      */
     void allMonitored(bool monitored);
 
     /**
      * This signal is emitted if the Monitor starts or stops monitoring @p tag explicitly.
      * @param tag The tag.
      * @param monitored Whether the tag is now being monitored or not.
      * @since 4.13
      */
     void tagMonitored(const Akonadi::Tag &tag, bool monitored);
 
     /**
      * This signal is emitted if the Monitor starts or stops monitoring @p type explicitly
      * @param type The type.
      * @param monitored Whether the type is now being monitored or not.
      * @since 4.13
      */
     void typeMonitored(const Akonadi::Monitor::Type type, bool monitored);
 
     void monitorReady();
 
 protected:
     /// @cond PRIVATE
     void connectNotify(const QMetaMethod &signal) override;
     void disconnectNotify(const QMetaMethod &signal) override;
 
     friend class EntityTreeModel;
     friend class EntityTreeModelPrivate;
     std::unique_ptr<MonitorPrivate> const d_ptr;
     explicit Monitor(MonitorPrivate *d, QObject *parent = nullptr);
     /// @endcond
 
 private:
     Q_DECLARE_PRIVATE(Monitor)
 
     /// @cond PRIVATE
     Q_PRIVATE_SLOT(d_ptr, void handleCommands())
     Q_PRIVATE_SLOT(d_ptr, void invalidateCollectionCache(qint64))
     Q_PRIVATE_SLOT(d_ptr, void invalidateItemCache(qint64))
     Q_PRIVATE_SLOT(d_ptr, void invalidateTagCache(qint64))
 
     friend class ResourceBasePrivate;
     /// @endcond
 };
 
 }