File indexing completed on 2024-05-12 17:08:53

 /*
     SPDX-FileCopyrightText: 2019 Marco Martin <mart@kde.org>
 
     SPDX-License-Identifier: LGPL-2.0-or-later
 */
 
 #pragma once
 
 #include "appletslayout.h"
 #include <QObject>
 
 class ItemContainer;
 
 class AbstractLayoutManager : public QObject
 {
     Q_OBJECT
 
 public:
     AbstractLayoutManager(AppletsLayout *layout);
     ~AbstractLayoutManager();
 
     AppletsLayout *layout() const;
 
     void setCellSize(const QSizeF &size);
     QSizeF cellSize() const;
 
     /**
      * A size aligned to the gid that fully contains the given size
      */
     QSizeF cellAlignedContainingSize(const QSizeF &size) const;
 
     /**
      * Positions the item, does *not* assign the space as taken
      */
     void positionItem(ItemContainer *item);
 
     /**
      * Positions the item and assigns the space as taken by this item
      */
     void positionItemAndAssign(ItemContainer *item);
 
     /**
      * Set the space of item's rect as occupied by item.
      * The operation may fail if some space of the item's geometry is already occupied.
      * @returns true if the operation succeeded
      */
     bool assignSpace(ItemContainer *item);
 
     /**
      * If item is occupying space, set it as available
      */
     void releaseSpace(ItemContainer *item);
 
     // VIRTUALS
     virtual QString serializeLayout() const = 0;
 
     virtual void parseLayout(const QString &savedLayout) = 0;
 
     virtual void layoutGeometryChanged(const QRectF &newGeometry, const QRectF &oldGeometry);
 
     /**
      * true if the item is managed by the grid
      */
     virtual bool itemIsManaged(ItemContainer *item) = 0;
 
     /**
      * Forget about layout information and relayout all items based solely on their current geometry
      */
     virtual void resetLayout() = 0;
 
     /**
      * Forget about layout information and relayout all items based on their stored geometry first,
      * and if that fails from their current geometry.
      * If this function has been called from a resize, oldGeomety and newGeometry
      * represent the geometries that this layout had before and after the resize, for placing strategies
      * of items that weren't in the stored config.
      * If one of those rects are empty, neither should be considered in the layouting strategy.
      */
     virtual void resetLayoutFromConfig(const QRectF &newGeom, const QRectF &oldGeom) = 0;
 
     /**
      * Restores an item geometry from the serialized config
      * parseLayout needs to be called before this
      * @returns true if the item was stored in the config
      * and the restore has been performed.
      * Otherwise, the item is not touched and returns false
      */
     virtual bool restoreItem(ItemContainer *item) = 0;
 
     /**
      * @returns true if the given rectangle is all free space
      */
     virtual bool isRectAvailable(const QRectF &rect) = 0;
 
 Q_SIGNALS:
     /**
      * Emitted when the layout has been changed and now needs saving
      */
     void layoutNeedsSaving();
 
 protected:
     /**
      * Subclasses implement their assignSpace logic here
      */
     virtual bool assignSpaceImpl(ItemContainer *item) = 0;
 
     /**
      * Subclasses implement their releasespace logic here
      */
     virtual void releaseSpaceImpl(ItemContainer *item) = 0;
 
     /**
      * @returns a rectangle big at least as minimumSize, trying to be as near as possible to the current item's geometry, displaced in the direction we asked,
      * forwards or backwards
      * @param item the item container we want to place an item in
      * @param minimumSize the minimum size we need to make sure is available
      * @param direction the preferred item layout direction, can be Closest, LeftToRight, RightToLeft, TopToBottom, and BottomToTop
      */
     virtual QRectF nextAvailableSpace(ItemContainer *item, const QSizeF &minimumSize, AppletsLayout::PreferredLayoutDirection direction) const = 0;
 
 private:
     QRectF candidateGeometry(ItemContainer *item) const;
 
     AppletsLayout *m_layout;
 
     // size in pixels of a crid cell
     QSizeF m_cellSize;
 };