/*

 *  The ManaPlus Client

 *  Copyright (C) 2004-2009  The Mana World Development Team

 *  Copyright (C) 2009-2010  The Mana Developers

 *  Copyright (C) 2011-2019  The ManaPlus Developers

 *  Copyright (C) 2019-2021  Andrei Karas

 *

 *  This file is part of The ManaPlus Client.

 *

 *  This program is free software; you can redistribute it and/or modify

 *  it under the terms of the GNU General Public License as published by

 *  the Free Software Foundation; either version 2 of the License, or

 *  any later version.

 *

 *  This program 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 General Public License for more details.

 *

 *  You should have received a copy of the GNU General Public License

 *  along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

/*      _______   __   __   __   ______   __   __   _______   __   __

 *     / _____/\ / /\ / /\ / /\ / ____/\ / /\ / /\ / ___  /\ /  |\/ /\

 *    / /\____\// / // / // / // /\___\// /_// / // /\_/ / // , |/ / /

 *   / / /__   / / // / // / // / /    / ___  / // ___  / // /| ' / /

 *  / /_// /\ / /_// / // / // /_/_   / / // / // /\_/ / // / |  / /

 * /______/ //______/ //_/ //_____/\ /_/ //_/ //_/ //_/ //_/ /|_/ /

 * \______\/ \______\/ \_\/ \_____\/ \_\/ \_\/ \_\/ \_\/ \_\/ \_\/

 *

 * Copyright (c) 2004 - 2008 Olof Naessén and Per Larsson

 *

 *

 * Per Larsson a.k.a finalman

 * Olof Naessén a.k.a jansem/yakslem

 *

 * Visit: http://guichan.sourceforge.net

 *

 * License: (BSD)

 * Redistribution and use in source and binary forms, with or without

 * modification, are permitted provided that the following conditions

 * are met:

 * 1. Redistributions of source code must retain the above copyright

 *    notice, this list of conditions and the following disclaimer.

 * 2. Redistributions in binary form must reproduce the above copyright

 *    notice, this list of conditions and the following disclaimer in

 *    the documentation and/or other materials provided with the

 *    distribution.

 * 3. Neither the name of Guichan nor the names of its contributors may

 *    be used to endorse or promote products derived from this software

 *    without specific prior written permission.

 *

 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS

 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT

 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR

 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT

 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,

 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED

 * TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR

 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF

 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING

 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS

 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

 */

#ifndef GUI_WIDGETS_SCROLLAREA_H

#define GUI_WIDGETS_SCROLLAREA_H

#include "gui/widgets/basiccontainer.h"

#include "enums/simpletypes/opaque.h"

#include "listeners/mouselistener.h"

#include "listeners/widgetlistener.h"

#include "localconsts.h"

class Image;

class ImageCollection;

/**

 * A scroll area.

 *

 * Contrary to Guichan's scroll area, this scroll area takes ownership over its

 * content. However, it won't delete a previously set content widget when

 * setContent is called!

 *

 * \ingroup GUI

 */

class ScrollArea final : public BasicContainer,

                         public MouseListener,

                         public WidgetListener

{

    public:

        /**

         * Scrollpolicies for the horizontal and vertical scrollbar.

         * The policies are:

         *

         * SHOW_ALWAYS - Always show the scrollbars no matter what.

         * SHOW_NEVER  - Never show the scrollbars no matter waht.

         * SHOW_AUTO   - Show the scrollbars only when needed. That is if the

         *               content grows larger then the ScrollArea.

         */

        enum ScrollPolicy

        {

            SHOW_ALWAYS = 0,

            SHOW_NEVER,

            SHOW_AUTO

        };

        ScrollArea(Widget2 *const widget2,

                   Widget *const widget,

                   const Opaque opaque,

                   const std::string &skin);

        A_DELETE_COPY(ScrollArea)

        /**

         * Destructor. Also deletes the content.

         */

        ~ScrollArea() override final;

        /**

         * Logic function optionally adapts width or height of contents. This

         * depends on the scrollbar settings.

         */

        void logic() override final;

        /**

         * Update the alpha value to the graphic components.

         */

        void updateAlpha();

        /**

         * Draws the scroll area.

         */

        void draw(Graphics *const graphics) override final A_NONNULL(2);

        void safeDraw(Graphics *const graphics) override final A_NONNULL(2);

        /**

         * Draws the background and border of the scroll area.

         */

        void drawFrame(Graphics *const graphics) override final A_NONNULL(2);

        void safeDrawFrame(Graphics *const graphics) override final

                           A_NONNULL(2);

        /**

         * Sets whether the widget should draw its background or not.

         */

        void setOpaque(Opaque opaque);

        /**

         * Returns whether the widget draws its background or not.

         */

        bool isOpaque() const noexcept2 A_WARN_UNUSED

        { return mOpaque == Opaque_true; }

        /**

         * Called when the mouse moves in the widget area.

         */

        void mouseMoved(MouseEvent& event) override final;

        /**

         * Called when the mouse enteres the widget area.

         */

        void mouseEntered(MouseEvent& event) override final;

        /**

         * Called when the mouse leaves the widget area.

         */

        void mouseExited(MouseEvent& event) override final;

        void mousePressed(MouseEvent& event) override final;

        void mouseReleased(MouseEvent& event) override final;

        void mouseDragged(MouseEvent &event) override final;

        void widgetResized(const Event &event) override final;

        void widgetMoved(const Event &event) override final;

        Rect getVerticalBarDimension() const;

        Rect getHorizontalBarDimension() const;

        Rect getVerticalMarkerDimension();

        Rect getHorizontalMarkerDimension();

        Rect getUpButtonDimension() const;

        Rect getDownButtonDimension() const;

        Rect getLeftButtonDimension() const;

        Rect getRightButtonDimension() const;

        /**

         * Sets the content.

         *

         * @param widget The content of the scroll area.

         */

        void setContent(Widget* widget);

        /**

         * Gets the content.

         *

         * @return The content of the scroll area.

         */

        Widget* getContent();

        /**

         * Sets the horizontal scrollbar policy. See enum with policies.

         *

         * @param hPolicy The policy for the horizontal scrollbar.

         * @see getHorizontalScrollPolicy

         */

        void setHorizontalScrollPolicy(const ScrollPolicy hPolicy);

        /**

         * Gets the horizontal scrollbar policy. See enum with policies.

         *

         * @return The policy for the horizontal scrollbar policy.

         * @see setHorizontalScrollPolicy, setScrollPolicy

         */

        ScrollPolicy getHorizontalScrollPolicy() const

        { return mHPolicy; }

        /**

         * Sets the vertical scrollbar policy. See enum with policies.

         *

         * @param vPolicy The policy for the vertical scrollbar.

         * @see getVerticalScrollPolicy

         */

        void setVerticalScrollPolicy(const ScrollPolicy vPolicy);

        /**

         * Gets the vertical scrollbar policy. See enum with policies.

         *

         * @return The policy for the vertical scrollbar.

         * @see setVerticalScrollPolicy, setScrollPolicy

         */

        ScrollPolicy getVerticalScrollPolicy() const

        { return mVPolicy; }

        /**

         * Sets the horizontal and vertical scrollbar policy.

         *

         * @param hPolicy The policy for the horizontal scrollbar.

         * @param vPolicy The policy for the vertical scrollbar.

         * @see getVerticalScrollPolicy, getHorizontalScrollPolicy

         */

        void setScrollPolicy(const ScrollPolicy hPolicy,

                             const ScrollPolicy vPolicy);

        /**

         * Sets the amount to scroll vertically.

         *

         * @param vScroll The amount to scroll.

         * @see getVerticalScrollAmount

         */

        void setVerticalScrollAmount(const int vScroll);

        /**

         * Gets the amount that is scrolled vertically.

         *

         * @return The scroll amount on vertical scroll.

         * @see setVerticalScrollAmount, setScrollAmount

         */

        int getVerticalScrollAmount() const

        { return mVScroll; }

        /**

         * Sets the amount to scroll horizontally.

         *

         * @param hScroll The amount to scroll.

         * @see getHorizontalScrollAmount

         */

        void setHorizontalScrollAmount(int hScroll);

        /**

         * Gets the amount that is scrolled horizontally.

         *

         * @return The scroll amount on horizontal scroll.

         * @see setHorizontalScrollAmount, setScrollAmount

         */

        int getHorizontalScrollAmount() const

        { return mHScroll; }

        /**

         * Sets the amount to scroll horizontally and vertically.

         *

         * @param hScroll The amount to scroll on horizontal scroll.

         * @param vScroll The amount to scroll on vertical scroll.

         * @see getHorizontalScrollAmount, getVerticalScrollAmount

         */

        void setScrollAmount(const int hScroll, const int vScroll);

        /**

         * Gets the maximum amount of horizontal scroll.

         *

         * @return The horizontal max scroll.

         */

        int getHorizontalMaxScroll();

        /**

         * Gets the maximum amount of vertical scroll.

         *

         * @return The vertical max scroll.

         */

        int getVerticalMaxScroll();

        /**

         * Sets the width of the scroll bars.

         *

         * @param width The width of the scroll bars.

         * @see getScrollbarWidth

         */

        void setScrollbarWidth(const int width);

        /**

         * Gets the width of the scroll bars.

         *

         * @return the width of the ScrollBar.

         * @see setScrollbarWidth

         */

        int getScrollbarWidth() const

        { return mScrollbarWidth; }

        /**

         * Sets the amount to scroll in pixels when the left scroll button is

         * pushed.

         *

         * @param amount The amount to scroll in pixels.

         * @see getLeftButtonScrollAmount

         */

        void setLeftButtonScrollAmount(const int amount)

        /**

         * Sets the amount to scroll in pixels when the right scroll button is

         * pushed.

         *

         * @param amount The amount to scroll in pixels.

         * @see getRightButtonScrollAmount

         */

        void setRightButtonScrollAmount(const int amount)

        /**

         * Sets the amount to scroll in pixels when the up scroll button is

         * pushed.

         *

         * @param amount The amount to scroll in pixels.

         * @see getUpButtonScrollAmount

         */

        void setUpButtonScrollAmount(const int amount)

        /**

         * Sets the amount to scroll in pixels when the down scroll button is

         * pushed.

         *

         * @param amount The amount to scroll in pixels.

         * @see getDownButtonScrollAmount

         */

        void setDownButtonScrollAmount(const int amount)

        /**

         * Gets the amount to scroll in pixels when the left scroll button is

         * pushed.

         *

         * @return The amount to scroll in pixels.

         * @see setLeftButtonScrollAmount

         */

        int getLeftButtonScrollAmount() const

        { return mLeftButtonScrollAmount; }

        /**

         * Gets the amount to scroll in pixels when the right scroll button is

         * pushed.

         *

         * @return The amount to scroll in pixels.

         * @see setRightButtonScrollAmount

         */

        int getRightButtonScrollAmount() const

        { return mRightButtonScrollAmount; }

        /**

         * Gets the amount to scroll in pixels when the up scroll button is

         * pushed.

         *

         * @return The amount to scroll in pixels.

         * @see setUpButtonScrollAmount

         */

        int getUpButtonScrollAmount() const

        { return mUpButtonScrollAmount; }

        /**

         * Gets the amount to scroll in pixels when the down scroll button is

         * pushed.

         *

         * @return The amount to scroll in pixels.

         * @see setDownButtonScrollAmount

         */

        int getDownButtonScrollAmount() const

        { return mDownButtonScrollAmount; }

        void showWidgetPart(Widget *const widget,

                            const Rect &area) override final;

        Rect getChildrenArea() override final;

        Widget *getWidgetAt(int x, int y) override final;

        void setWidth(int width);

        void setHeight(int height);

        void setDimension(const Rect& dimension);

        void mouseWheelMovedUp(MouseEvent& event) override final;

        void mouseWheelMovedDown(MouseEvent& event) override final;

        bool isSelectable() const noexcept2 override final A_WARN_UNUSED;

    protected:

        enum BUTTON_DIR

        {

            UP = 0,

            DOWN,

            LEFT,

            RIGHT,

            BUTTONS_DIR

        };

        /**

         * Initializes the scroll area.

         */

        void init(std::string skinName);

        /**

         * Checks the policies for the scroll bars.

         */

        void checkPolicies();

        void drawButton(Graphics *const graphics,

                        const BUTTON_DIR dir) A_NONNULL(2);

        void calcButton(Graphics *const graphics,

                        const BUTTON_DIR dir) A_NONNULL(2);

        void drawVBar(Graphics *const graphics) const A_NONNULL(2);

        void drawHBar(Graphics *const graphics) const A_NONNULL(2);

        void drawVMarker(Graphics *const graphics) A_NONNULL(2);

        void drawHMarker(Graphics *const graphics) A_NONNULL(2);

        void calcVBar(const Graphics *const graphics) A_NONNULL(2);

        void calcHBar(const Graphics *const graphics) A_NONNULL(2);

        void calcVMarker(Graphics *const graphics) A_NONNULL(2);

        void calcHMarker(Graphics *const graphics) A_NONNULL(2);

        Image *getImageByState(Rect &dim, const BUTTON_DIR dir);

        void updateCalcFlag(const Graphics *const graphics) A_NONNULL(2);

        static int instances;

        static float mAlpha;

        static bool mShowButtons;

        static int mMarkerSize;

        static int mScrollbarSize;

        static ImageRect background;

        static ImageRect vMarker;

        static ImageRect vMarkerHi;

        static ImageRect vBackground;

        static ImageRect hBackground;

        static Image *buttons[4][2];

        ImageCollection *mVertexes A_NONNULLPOINTER;

        ImageCollection *mVertexes2 A_NONNULLPOINTER;

        /**

         * Holds the horizontal scroll bar policy.

         */

        ScrollPolicy mHPolicy;

        /**

         * Holds the vertical scroll bar policy.

         */

        ScrollPolicy mVPolicy;

        /**

         * Holds the vertical scroll amount.

         */

        int mVScroll;

        /**

         * Holds the horizontal scroll amount.

         */

        int mHScroll;

        /**

         * Holds the width of the scroll bars.

         */

        int mScrollbarWidth;

        /**

         * Holds the up button scroll amount.

         */

        int mUpButtonScrollAmount;

        /**

         * Holds the down button scroll amount.

         */

        int mDownButtonScrollAmount;

        /**

         * Holds the left button scroll amount.

         */

        int mLeftButtonScrollAmount;

        /**

         * Holds the right button scroll amount.

         */

        int mRightButtonScrollAmount;

        /**

         * Holds the horizontal markers drag offset.

         */

        int mHorizontalMarkerDragOffset;

        /**

         * Holds the vertical markers drag offset.

         */

        int mVerticalMarkerDragOffset;

        int mX;

        int mY;

        int mClickX;

        int mClickY;

        int mXOffset;

        int mYOffset;

        int mDrawWidth;

        int mDrawHeight;

        /**

         * True if the vertical scroll bar is visible, false otherwise.

         */

        bool mVBarVisible;

        /**

         * True if the horizontal scroll bar is visible, false otherwise.

         */

        bool mHBarVisible;

        /**

         * True if the up button is pressed, false otherwise.

         */

        bool mUpButtonPressed;

        /**

         * True if the down button is pressed, false otherwise.

         */

        bool mDownButtonPressed;

        /**

         * True if the left button is pressed, false otherwise.

         */

        bool mLeftButtonPressed;

        /**

         * True if the right button is pressed, false otherwise.

         */

        bool mRightButtonPressed;

        /**

         * True if the vertical marked is dragged.

         */

        bool mIsVerticalMarkerDragged;

        /**

         * True if the horizontal marked is dragged.

         */

        bool mIsHorizontalMarkerDragged;

        /**

         * True if the scroll area should be opaque (that is

         * display its background), false otherwise.

         */

        Opaque mOpaque;

        bool mHasMouse;

};

#endif  // GUI_WIDGETS_SCROLLAREA_H