File indexing completed on 2024-05-19 16:34:53

 /*
     KWin - the KDE window manager
     This file is part of the KDE project.
 
     SPDX-FileCopyrightText: 2012 Martin Gräßlin <mgraesslin@kde.org>
 
     SPDX-License-Identifier: GPL-2.0-or-later
 */
 #pragma once
 // Qt
 #include <QHash>
 #include <QObject>
 #include <QVector>
 
 namespace KWin
 {
 namespace TabBox
 {
 
 /**
  * @brief A chain for last recently used virtual desktops.
  */
 class DesktopChain
 {
 public:
     /**
      * Creates a last recently used virtual desktop chain with the given @p initialSize.
      */
     explicit DesktopChain(uint initialSize = 0);
     /**
      * Returns the next desktop in the chain starting from @p indexDesktop.
      * In case that the @p indexDesktop is the last desktop of the chain, the method wraps around
      * and returns the first desktop stored in the chain.
      * In case the chain is valid, but does not contain the @p indexDesktop, the first element of
      * the chain is returned.
      * In case the chain is not valid, the always valid virtual desktop with identifier @c 1
      * is returned.
      * @param indexDesktop The id of the virtual desktop which should be used as a starting point
      * @return The next virtual desktop in the chain
      */
     uint next(uint indexDesktop) const;
     /**
      * Adds the @p desktop to the chain. The @p desktop becomes the first element of the
      * chain. All desktops in the chain from the previous index of @p desktop are moved
      * one position in the chain.
      * @param desktop The new desktop to be the top most element in the chain.
      */
     void add(uint desktop);
     /**
      * Resizes the chain from @p previousSize to @p newSize.
      * In case the chain grows new elements are added with a meaning full id in the range
      * [previousSize, newSize].
      * In case the chain shrinks it is ensured that no element points to a virtual desktop
      * with an id larger than @p newSize.
      * @param previousSize The previous size of the desktop chain
      * @param newSize The size to be used for the desktop chain
      */
     void resize(uint previousSize, uint newSize);
 
 private:
     /**
      * Initializes the chain with default values.
      */
     void init();
     QVector<uint> m_chain;
 };
 
 /**
  * @brief A manager for multiple desktop chains.
  *
  * This manager keeps track of multiple desktop chains which have a given identifier.
  * A common usage for this is to have a different desktop chain for each Activity.
  */
 class DesktopChainManager : public QObject
 {
     Q_OBJECT
 
 public:
     explicit DesktopChainManager(QObject *parent = nullptr);
     ~DesktopChainManager() override;
 
     /**
      * Returns the next virtual desktop starting from @p indexDesktop in the currently used chain.
      * @param indexDesktop The id of the virtual desktop which should be used as a starting point
      * @return The next virtual desktop in the currently used chain
      * @see DesktopChain::next
      */
     uint next(uint indexDesktop) const;
 
 public Q_SLOTS:
     /**
      * Adds the @p currentDesktop to the currently used desktop chain.
      * @param previousDesktop The previously used desktop, should be the top element of the chain
      * @param currentDesktop The desktop which should be the new top element of the chain
      */
     void addDesktop(uint previousDesktop, uint currentDesktop);
     /**
      * Resizes all managed desktop chains from @p previousSize to @p newSize.
      * @param previousSize The previously used size for the chains
      * @param newSize The size to be used for the chains
      * @see DesktopChain::resize
      */
     void resize(uint previousSize, uint newSize);
     /**
      * Switches to the desktop chain identified by the given @p identifier.
      * If there is no chain yet for the given @p identifier a new chain is created and used.
      * @param identifier The identifier of the desktop chain to be used
      */
     void useChain(const QString &identifier);
 
 private:
     typedef QHash<QString, DesktopChain> DesktopChains;
     /**
      * Creates a new desktop chain for the given @p identifier and adds it to the list
      * of identifiers.
      * @returns Position of the new chain in the managed list of chains
      */
     DesktopChains::Iterator addNewChain(const QString &identifier);
     /**
      * Creates the very first list to be used when an @p identifier comes in.
      * The dummy chain which is used by default gets copied and used for this chain.
      */
     void createFirstChain(const QString &identifier);
 
     DesktopChains::Iterator m_currentChain;
     DesktopChains m_chains;
     /**
      * The maximum size to be used for a new desktop chain
      */
     uint m_maxChainSize;
 };
 
 } // TabBox
 } // namespace KWin