#ifndef DockManagerH
#define DockManagerH
/*******************************************************************************
** Qt Advanced Docking System
** Copyright (C) 2017 Uwe Kindler
**
** This library is free software; you can redistribute it and/or
** modify it under the terms of the GNU Lesser General Public
** License as published by the Free Software Foundation; either
** version 2.1 of the License, or (at your option) any later version.
**
** This library is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
** Lesser General Public License for more details.
**
** You should have received a copy of the GNU Lesser General Public
** License along with this library; If not, see <http://www.gnu.org/licenses/>.
******************************************************************************/


//============================================================================
/// \file   DockManager.h
/// \author Uwe Kindler
/// \date   26.02.2017
/// \brief  Declaration of CDockManager class
//============================================================================


//============================================================================
//                                   INCLUDES
//============================================================================
#include "ads_globals.h"
#include "DockContainerWidget.h"
#include "DockWidget.h"
#include "FloatingDockContainer.h"


QT_FORWARD_DECLARE_CLASS(QSettings)
QT_FORWARD_DECLARE_CLASS(QMenu)

namespace ads
{
struct DockManagerPrivate;
class CFloatingDockContainer;
struct FloatingDockContainerPrivate;
class CDockContainerWidget;
class DockContainerWidgetPrivate;
class CDockOverlay;
class CDockAreaTabBar;
class CDockWidgetTab;
struct DockWidgetTabPrivate;
struct DockAreaWidgetPrivate;
class CIconProvider;
class CDockComponentsFactory;

/**
 * The central dock manager that maintains the complete docking system.
 * With the configuration flags you can globally control the functionality
 * of the docking system. The dock manager uses an internal stylesheet to
 * style its components like splitters, tabs and buttons. If you want to
 * disable this stylesheet because your application uses its own,
 * just call the function for settings the stylesheet with an empty
 * string.
 * \code
 * DockManager->setStyleSheet("");
 * \endcode
 **/
class ADS_EXPORT CDockManager : public CDockContainerWidget
{
	Q_OBJECT
private:
	DockManagerPrivate* d; ///< private data (pimpl)
	friend struct DockManagerPrivate;
	friend class CFloatingDockContainer;
	friend struct FloatingDockContainerPrivate;
	friend class CDockContainerWidget;
	friend class DockContainerWidgetPrivate;
	friend class CDockAreaTabBar;
	friend class CDockWidgetTab;
	friend struct DockAreaWidgetPrivate;
	friend struct DockWidgetTabPrivate;
	friend class CFloatingDragPreview;
	friend struct FloatingDragPreviewPrivate;
	friend class CDockAreaTitleBar;


protected:
	/**
	 * Registers the given floating widget in the internal list of
	 * floating widgets
	 */
	void registerFloatingWidget(CFloatingDockContainer* FloatingWidget);

	/**
	 * Remove the given floating widget from the list of registered floating
	 * widgets
	 */
	void removeFloatingWidget(CFloatingDockContainer* FloatingWidget);

	/**
	 * Registers the given dock container widget
	 */
	void registerDockContainer(CDockContainerWidget* DockContainer);

	/**
	 * Remove dock container from the internal list of registered dock
	 * containers
	 */
	void removeDockContainer(CDockContainerWidget* DockContainer);

	/**
	 * Overlay for containers
	 */
	CDockOverlay* containerOverlay() const;

	/**
	 * Overlay for dock areas
	 */
	CDockOverlay* dockAreaOverlay() const;


	/**
	 * A container needs to call this function if a widget has been dropped
	 * into it
	 */
	void notifyWidgetOrAreaRelocation(QWidget* RelocatedWidget);

	/**
	 * This function is called, if a floating widget has been dropped into
	 * an new position.
	 * When this function is called, all dock widgets of the FloatingWidget
	 * are already inserted into its new position
	 */
	void notifyFloatingWidgetDrop(CFloatingDockContainer* FloatingWidget);


	/**
	 * Show the floating widgets that has been created floating
	 */
	virtual void showEvent(QShowEvent *event) override;

public:
	using Super = CDockContainerWidget;

	enum eViewMenuInsertionOrder
	{
		MenuSortedByInsertion,
		MenuAlphabeticallySorted
	};

	/**
	 * These global configuration flags configure some global dock manager
	 * settings.
	 * Set the dock manager flags, before you create the dock manager instance.
	 */
	enum eConfigFlag
	{
		ActiveTabHasCloseButton = 0x0001,    //!< If this flag is set, the active tab in a tab area has a close button
		DockAreaHasCloseButton = 0x0002,     //!< If the flag is set each dock area has a close button
		DockAreaCloseButtonClosesTab = 0x0004,//!< If the flag is set, the dock area close button closes the active tab, if not set, it closes the complete dock area
		OpaqueSplitterResize = 0x0008, //!< See QSplitter::setOpaqueResize() documentation
		XmlAutoFormattingEnabled = 0x0010,//!< If enabled, the XML writer automatically adds line-breaks and indentation to empty sections between elements (ignorable whitespace).
		XmlCompressionEnabled = 0x0020,//!< If enabled, the XML output will be compressed and is not human readable anymore
		TabCloseButtonIsToolButton = 0x0040,//! If enabled the tab close buttons will be QToolButtons instead of QPushButtons - disabled by default
		AllTabsHaveCloseButton = 0x0080, //!< if this flag is set, then all tabs that are closable show a close button
		RetainTabSizeWhenCloseButtonHidden = 0x0100, //!< if this flag is set, the space for the close button is reserved even if the close button is not visible
		OpaqueUndocking = 0x0200,///< If enabled, the widgets are immediately undocked into floating widgets, if disabled, only a draw preview is undocked and the real undocking is deferred until the mouse is released
		DragPreviewIsDynamic = 0x0400,///< If opaque undocking is disabled, this flag defines the behavior of the drag preview window, if this flag is enabled, the preview will be adjusted dynamically to the drop area
		DragPreviewShowsContentPixmap = 0x0800,///< If opaque undocking is disabled, the created drag preview window shows a copy of the content of the dock widget / dock are that is dragged
		DragPreviewHasWindowFrame = 0x1000,///< If opaque undocking is disabled, then this flag configures if the drag preview is frameless or looks like a real window
		AlwaysShowTabs = 0x2000,///< If this option is enabled, the tab of a dock widget is always displayed - even if it is the only visible dock widget in a floating widget.
		DockAreaHasUndockButton = 0x4000,     //!< If the flag is set each dock area has an undock button
		DockAreaHasTabsMenuButton = 0x8000,     //!< If the flag is set each dock area has a tabs menu button
		DockAreaHideDisabledButtons = 0x10000,    //!< If the flag is set disabled dock area buttons will not appear on the toolbar at all (enabling them will bring them back)
		DockAreaDynamicTabsMenuButtonVisibility = 0x20000, //!< If the flag is set, the tabs menu button will be shown only when it is required - that means, if the tabs are elided. If the tabs are not elided, it is hidden
		FloatingContainerHasWidgetTitle = 0x40000, //!< If set, the Floating Widget window title reflects the title of the current dock widget otherwise it displays application name as window title
		FloatingContainerHasWidgetIcon = 0x80000, //!< If set, the Floating Widget icon reflects the icon of the current dock widget otherwise it displays application icon
		HideSingleCentralWidgetTitleBar = 0x100000, //!< If there is only one single visible dock widget in the main dock container (the dock manager) and if this flag is set, then the titlebar of this dock widget will be hidden
		                                            //!< this only makes sense for non draggable and non floatable widgets and enables the creation of some kind of "central" widget
		FocusHighlighting = 0x200000, //!< enables styling of focused dock widget tabs or floating widget titlebar
		EqualSplitOnInsertion = 0x400000, ///!< if enabled, the space is equally distributed to all widgets in a  splitter

        DefaultDockAreaButtons = DockAreaHasCloseButton
							   | DockAreaHasUndockButton
		                       | DockAreaHasTabsMenuButton,///< default configuration of dock area title bar buttons

		DefaultBaseConfig = DefaultDockAreaButtons
		                  | ActiveTabHasCloseButton
		                  | XmlCompressionEnabled
		                  | FloatingContainerHasWidgetTitle,///< default base configuration settings

        DefaultOpaqueConfig = DefaultBaseConfig
		                    | OpaqueSplitterResize
		                    | OpaqueUndocking, ///< the default configuration with opaque operations - this may cause issues if ActiveX or Qt 3D windows are involved

		DefaultNonOpaqueConfig = DefaultBaseConfig
		              | DragPreviewShowsContentPixmap, ///< the default configuration for non opaque operations

		NonOpaqueWithWindowFrame = DefaultNonOpaqueConfig
		              | DragPreviewHasWindowFrame ///< the default configuration for non opaque operations that show a real window with frame
	};
	Q_DECLARE_FLAGS(ConfigFlags, eConfigFlag)

	/**
	 * Default Constructor.
	 * If the given parent is a QMainWindow, the dock manager sets itself as the
	 * central widget.
	 * Before you create any dock widgets, you should properly setup the
	 * configuration flags via setConfigFlags().
	 */
	CDockManager(QWidget* parent = nullptr);

	/**
	 * Virtual Destructor
	 */
	virtual ~CDockManager() override;

	/**
	 * This function returns the global configuration flags
	 */
	static ConfigFlags configFlags();

	/**
	 * Sets the global configuration flags for the whole docking system.
	 * Call this function before you create the dock manager and before
	 * your create the first dock widget.
	 */
	static void setConfigFlags(const ConfigFlags Flags);

	/**
	 * Set a certain config flag.
	 * \see setConfigFlags()
	 */
	static void setConfigFlag(eConfigFlag Flag, bool On = true);

	/**
	 * Returns true if the given config flag is set
	 */
	static bool testConfigFlag(eConfigFlag Flag);

	/**
	 * Returns the global icon provider.
	 * The icon provider enables the use of custom icons in case using
	 * styleheets for icons is not an option.
	 */
	static CIconProvider& iconProvider();

	/**
	 * Adds dockwidget into the given area.
	 * If DockAreaWidget is not null, then the area parameter indicates the area
	 * into the DockAreaWidget. If DockAreaWidget is null, the Dockwidget will
	 * be dropped into the container. If you would like to add a dock widget
	 * tabified, then you need to add it to an existing dock area object
	 * into the CenterDockWidgetArea. The following code shows this:
	 * \code
	 * DockManager->addDockWidget(ads::CenterDockWidgetArea, NewDockWidget,
	 * 	   ExisitingDockArea);
	 * \endcode
	 * \return Returns the dock area widget that contains the new DockWidget
	 */
	CDockAreaWidget* addDockWidget(DockWidgetArea area, CDockWidget* Dockwidget,
		CDockAreaWidget* DockAreaWidget = nullptr);

	/**
	 * This function will add the given Dockwidget to the given dock area as
	 * a new tab.
	 * If no dock area widget exists for the given area identifier, a new
	 * dock area widget is created.
	 */
	CDockAreaWidget* addDockWidgetTab(DockWidgetArea area,
		CDockWidget* Dockwidget);

	/**
	 * This function will add the given Dockwidget to the given DockAreaWidget
	 * as a new tab.
	 */
	CDockAreaWidget* addDockWidgetTabToArea(CDockWidget* Dockwidget,
		CDockAreaWidget* DockAreaWidget);

	/**
	 * Adds the given DockWidget floating and returns the created
	 * CFloatingDockContainer instance.
	 */
	CFloatingDockContainer* addDockWidgetFloating(CDockWidget* Dockwidget);

	/**
	 * Searches for a registered doc widget with the given ObjectName
	 * \return Return the found dock widget or nullptr if a dock widget with the
	 * given name is not registered
	 */
	CDockWidget* findDockWidget(const QString& ObjectName) const;

	/**
	 * Remove the given Dock from the dock manager
	 */
	void removeDockWidget(CDockWidget* Dockwidget);

	/**
	 * This function returns a readable reference to the internal dock
	 * widgets map so that it is possible to iterate over all dock widgets
	 */
	QMap<QString, CDockWidget*> dockWidgetsMap() const;

	/**
	 * Returns the list of all active and visible dock containers
	 * Dock containers are the main dock manager and all floating widgets
	 */
	const QList<CDockContainerWidget*> dockContainers() const;

	/**
	 * Returns the list of all floating widgets
	 */
	const QList<CFloatingDockContainer*> floatingWidgets() const;

	/**
	 * This function always return 0 because the main window is always behind
	 * any floating widget
	 */
	unsigned int zOrderIndex() const override;

	/**
	 * Saves the current state of the dockmanger and all its dock widgets
	 * into the returned QByteArray.
	 * The XmlMode enables / disables the auto formatting for the XmlStreamWriter.
	 * If auto formatting is enabled, the output is intended and line wrapped.
	 * The XmlMode XmlAutoFormattingDisabled is better if you would like to have
	 * a more compact XML output - i.e. for storage in ini files.
	 * The version number is stored as part of the data.
	 * To restore the saved state, pass the return value and version number
	 * to restoreState().
	 * \see restoreState()
	 */
	QByteArray saveState(int version = 0) const;

	/**
	 * Restores the state of this dockmanagers dockwidgets.
	 * The version number is compared with that stored in state. If they do
	 * not match, the dockmanager's state is left unchanged, and this function
	 * returns false; otherwise, the state is restored, and this function
	 * returns true.
	 * \see saveState()
	 */
	bool restoreState(const QByteArray &state, int version = 0);

	/**
	 * Saves the current perspective to the internal list of perspectives.
	 * A perspective is the current state of the dock manager assigned
	 * with a certain name. This makes it possible for the user,
	 * to switch between different perspectives quickly.
	 * If a perspective with the given name already exists, then
	 * it will be overwritten with the new state.
	 */
	void addPerspective(const QString& UniquePrespectiveName);

	/**
	 * Removes the perspective with the given name from the list of perspectives
	 */
	void removePerspective(const QString& Name);

	/**
	 * Removes the given perspectives from the dock manager
	 */
	void removePerspectives(const QStringList& Names);

	/**
	 * Returns the names of all available perspectives
	 */
	QStringList perspectiveNames() const;

	/**
	 * Saves the perspectives to the given settings file.
	 */
	void savePerspectives(QSettings& Settings) const;

	/**
	 * Loads the perspectives from the given settings file
	 */
	void loadPerspectives(QSettings& Settings);

	/**
	 * Adds a toggle view action to the the internal view menu.
	 * You can either manage the insertion of the toggle view actions in your
	 * application or you can add the actions to the internal view menu and
	 * then simply insert the menu object into your.
	 * \param[in] ToggleViewAction The action to insert. If no group is provided
	 *            the action is directly inserted into the menu. If a group
	 *            is provided, the action is inserted into the group and the
	 *            group is inserted into the menu if it is not existing yet.
	 * \param[in] Group This is the text used for the group menu item
	 * \param[in] GroupIcon The icon used for grouping the workbenches in the
	 *            view menu. I.e. if there is a workbench for each device
	 *            like for spectrometer devices, it is good to group all these
	 *            workbenches under a menu item
	 * \return If Group is not empty, this function returns the GroupAction
	 *         for this group. If the group is empty, the function returns
	 *         the given ToggleViewAction.
	 */
	QAction* addToggleViewActionToMenu(QAction* ToggleViewAction,
		const QString& Group = QString(), const QIcon& GroupIcon = QIcon());

	/**
	 * This function returns the internal view menu.
	 * To fill the view menu, you can use the addToggleViewActionToMenu()
	 * function.
	 */
	QMenu* viewMenu() const;

	/**
	 * Define the insertion order for toggle view menu items.
	 * The order defines how the actions are added to the view menu.
	 * The default insertion order is MenuAlphabeticallySorted to make it
	 * easier for users to find the menu entry for a certain dock widget.
	 * You need to call this function befor you insert the first menu item
	 * into the view menu.
	 */
	void setViewMenuInsertionOrder(eViewMenuInsertionOrder Order);

	/**
	 * This function returns true between the restoringState() and
	 * stateRestored() signals.
	 */
	bool isRestoringState() const;

	/**
	 * The distance the user needs to move the mouse with the left button
	 * hold down before a dock widget start floating
	 */
	static int startDragDistance();

	/**
	 * Helper function to set focus depending on the configuration of the
	 * FocusStyling flag
	 */
	template <class QWidgetPtr>
	static void setWidgetFocus(QWidgetPtr widget)
	{
		if (!CDockManager::testConfigFlag(CDockManager::FocusHighlighting))
		{
			return;
		}

		widget->setFocus(Qt::OtherFocusReason);
	}

public slots:
	/**
	 * Opens the perspective with the given name.
	 */
	void openPerspective(const QString& PerspectiveName);

	/**
	 * Request a focus change to the given dock widget.
	 * This function only has an effect, if the flag CDockManager::FocusStyling
	 * is enabled
	 */
	void setDockWidgetFocused(CDockWidget* DockWidget);

signals:
	/**
	 * This signal is emitted if the list of perspectives changed
	 */
	void perspectiveListChanged();

	/**
	 * This signal is emitted if perspectives have been removed
	 */
	void perspectivesRemoved();

	/**
	 * This signal is emitted, if the restore function is called, just before
	 * the dock manager starts restoring the state.
	 * If this function is called, nothing has changed yet
	 */
	void restoringState();

    /**
     * This signal is emitted if the state changed in restoreState.
     * The signal is emitted if the restoreState() function is called or
     * if the openPerspective() function is called
     */
    void stateRestored();

    /**
     * This signal is emitted, if the dock manager starts opening a
     * perspective.
     * Opening a perspective may take more than a second if there are
     * many complex widgets. The application may use this signal
     * to show some progress indicator or to change the mouse cursor
     * into a busy cursor.
     */
    void openingPerspective(const QString& PerspectiveName);

    /**
     * This signal is emitted if the dock manager finished opening a
     * perspective.
     */
    void perspectiveOpened(const QString& PerspectiveName);

	/**
	 * This signal is emitted, if a new floating widget has been created.
	 * An application can use this signal to e.g. subscribe to events of
	 * the newly created window.
	 */
	void floatingWidgetCreated(CFloatingDockContainer* FloatingWidget);

    /**
     * This signal is emitted, if a new DockArea has been created.
     * An application can use this signal to set custom icons or custom
     * tooltips for the DockArea buttons.
     */
    void dockAreaCreated(CDockAreaWidget* DockArea);

    /**
     * This signal is emitted just before the given dock widget is removed
     * from the
     */
    void dockWidgetAboutToBeRemoved(CDockWidget* DockWidget);

    /**
     * This signal is emitted if a dock widget has been removed with the remove
     * removeDockWidget() function.
     * If this signal is emitted, the dock widget has been removed from the
     * docking system but it is not deleted yet.
     */
    void dockWidgetRemoved(CDockWidget* DockWidget);

    /**
     * This signal is emitted if the focused dock widget changed.
     * Both old and now can be nullptr.
     * The focused dock widget is the one that is highlighted in the GUI
     */
    void focusedDockWidgetChanged(CDockWidget* old, CDockWidget* now);
}; // class DockManager
} // namespace ads
//-----------------------------------------------------------------------------
#endif // DockManagerH
