/****************************************************************************
**
** Copyright (C) 2020 Uwe Kindler
** Contact: https://www.qt.io/licensing/
**
** This file is part of Qt Creator.
**
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 2.1 or (at your option) any later version.
** The licenses are as published by the Free Software Foundation
** and appearing in the file LICENSE.LGPLv21 included in the packaging
** of this file. Please review the following information to ensure
** the GNU Lesser General Public License version 2.1 requirements
** will be met: https://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 3 or (at your option) any later version
** approved by the KDE Free Qt Foundation. The licenses are as published by
** the Free Software Foundation and appearing in the file LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-3.0.html.
**
****************************************************************************/

#pragma once

#include "ads_globals.h"
#include "dockcontainerwidget.h"
#include "dockwidget.h"
#include "floatingdockcontainer.h"

#include <utils/persistentsettings.h>

#include <QByteArray>
#include <QDateTime>
#include <QFlags>
#include <QList>
#include <QMap>
#include <QString>
#include <QStringList>
#include <QtGui/QIcon>
#include <qobjectdefs.h>

QT_BEGIN_NAMESPACE
class QMenu;
class QSettings;
QT_END_NAMESPACE

namespace ADS {

namespace Constants {
const char FACTORY_DEFAULT_NAME[] = "factorydefault";
const char DEFAULT_NAME[] = "default";
const char STARTUP_WORKSPACE_SETTINGS_KEY[] = "QML/Designer/StartupWorkspace";
const char AUTO_RESTORE_WORKSPACE_SETTINGS_KEY[] = "QML/Designer/AutoRestoreLastWorkspace";
} // namespace Constants

class DockManagerPrivate;
class FloatingDockContainer;
class FloatingDockContainerPrivate;
class DockComponentsFactory;
class DockContainerWidget;
class DockContainerWidgetPrivate;
class DockOverlay;
class DockAreaTabBar;
class DockWidgetTab;
struct DockWidgetTabPrivate;
struct DockAreaWidgetPrivate;
class IconProvider;

/**
 * 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 DockManager : public DockContainerWidget
{
    Q_OBJECT
private:
    DockManagerPrivate *d; ///< private data (pimpl)
    friend class DockManagerPrivate;
    friend class FloatingDockContainer;
    friend class FloatingDockContainerPrivate;
    friend class DockContainerWidget;
    friend class DockContainerWidgetPrivate;
    friend class DockAreaTabBar;
    friend class DockWidgetTab;
    friend struct DockAreaWidgetPrivate;
    friend struct DockWidgetTabPrivate;
    friend class FloatingDragPreview;
    friend class FloatingDragPreviewPrivate;
    friend class DockAreaTitleBar;

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

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

    /**
     * Registers the given dock container widget
     */
    void registerDockContainer(DockContainerWidget *dockContainer);

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

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

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

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

public:
    using Super = DockContainerWidget;

    /**
     * These global configuration flags configure some global dock manager
     * settings.
     */
    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 tollbar at all (enabling them will bring them back)
        DockAreaDynamicTabsMenuButtonVisibility
        = 0x20000, //!< If the flag is set dock area will disable a tabs menu button when there is only one tab in the area
        FloatingContainerHasWidgetTitle
        = 0x40000,
        FloatingContainerHasWidgetIcon
        = 0x80000,

        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().
     */
    DockManager(QWidget *parent = nullptr);

    /**
     * Virtual Destructor
     */
    virtual ~DockManager() 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 your first dock widget.
     */
    static void setConfigFlags(const ConfigFlags flags);

    /**
     * Set a certain config flag
     */
    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 IconProvider &iconProvider();

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

    /**
     * Set the QtCreator settings.
     */
    void setSettings(QSettings *settings);

    /**
     * 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
     */
    DockAreaWidget *addDockWidget(DockWidgetArea area,
                                  DockWidget *dockWidget,
                                  DockAreaWidget *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.
     */
    DockAreaWidget *addDockWidgetTab(DockWidgetArea area, DockWidget *dockWidget);

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

    /**
     * Adds the given DockWidget floating and returns the created
     * CFloatingDockContainer instance.
     */
    FloatingDockContainer *addDockWidgetFloating(DockWidget *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
     */
    DockWidget *findDockWidget(const QString &objectName) const;

    /**
     * Remove the given Dock from the dock manager
     */
    void removeDockWidget(DockWidget *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, DockWidget *> 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<DockContainerWidget *> dockContainers() const;

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

    /**
     * This function always return 0 because the main window is always behind
     * any floating widget
     */
    virtual 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.
     */
    QByteArray saveState(int version = Version1) 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.
     */
    bool restoreState(const QByteArray &state, int version = Version1);

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

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

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

    /**
     * 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 openWorkspace() 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 openingWorkspace(const QString &workspaceName);

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

    /**
     * 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(FloatingDockContainer *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(DockAreaWidget *dockArea);

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

public:
    void showWorkspaceMananger();

    // higher level workspace management
    QString activeWorkspace() const;
    QString lastWorkspace() const;
    bool autoRestorLastWorkspace() const;
    QStringList workspaces();
    QDateTime workspaceDateTime(const QString &workspace) const;
    Utils::FilePath workspaceNameToFileName(const QString &workspaceName) const;

    bool createWorkspace(const QString &workspace);

    bool openWorkspace(const QString &workspace);

    bool confirmWorkspaceDelete(const QStringList &workspaces);
    bool deleteWorkspace(const QString &workspace);
    void deleteWorkspaces(const QStringList &workspaces);

    bool cloneWorkspace(const QString &original, const QString &clone);
    bool renameWorkspace(const QString &original, const QString &newName);

    bool save();

    bool isFactoryDefaultWorkspace(const QString &workspace) const;
    bool isDefaultWorkspace(const QString &workspace) const;

signals:
    void aboutToUnloadWorkspace(QString workspaceName);
    void aboutToLoadWorkspace(QString workspaceName);
    void workspaceLoaded(QString workspaceName);
    void aboutToSaveWorkspace();

private:
    bool write(const QByteArray &data, QString *errorString) const;
#ifdef QT_GUI_LIB
    bool write(const QByteArray &data, QWidget *parent) const;
#endif
}; // class DockManager

} // namespace ADS