/*      _______   __   __   __   ______   __   __   _______   __   __
 *     / _____/\ / /\ / /\ / /\ / ____/\ / /\ / /\ / ___  /\ /  |\/ /\
 *    / /\____\// / // / // / // /\___\// /_// / // /\_/ / // , |/ / /
 *   / / /__   / / // / // / // / /    / ___  / // ___  / // /| ' / /
 *  / /_// /\ / /_// / // / // /_/_   / / // / // /\_/ / // / |  / /
 * /______/ //______/ //_/ //_____/\ /_/ //_/ //_/ //_/ //_/ /|_/ /
 * \______\/ \______\/ \_\/ \_____\/ \_\/ \_\/ \_\/ \_\/ \_\/ \_\/
 *
 * Copyright (c) 2004, 2005 darkbits                        Js_./
 * Per Larsson a.k.a finalman                          _RqZ{a<^_aa
 * Olof Naessén a.k.a jansem/yakslem                _asww7!uY`>  )\a//
 *                                                 _Qhm`] _f "'c  1!5m
 * Visit: http://guichan.darkbits.org             )Qk<P ` _: :+' .'  "{[
 *                                               .)j(] .d_/ '-(  P .   S
 * License: (BSD)                                <Td/Z <fP"5(\"??"\a.  .L
 * Redistribution and use in source and          _dV>ws?a-?'      ._/L  #'
 * binary forms, with or without                 )4d[#7r, .   '     )d`)[
 * modification, are permitted provided         _Q-5'5W..j/?'   -?!\)cam'
 * that the following conditions are met:       j<<WP+k/);.        _W=j f
 * 1. Redistributions of source code must       .$%w\/]Q  . ."'  .  mj$
 *    retain the above copyright notice,        ]E.pYY(Q]>.   a     J@\
 *    this list of conditions and the           j(]1u<sE"L,. .   ./^ ]{a
 *    following disclaimer.                     4'_uomm\.  )L);-4     (3=
 * 2. Redistributions in binary form must        )_]X{Z('a_"a7'<a"a,  ]"[
 *    reproduce the above copyright notice,       #}<]m7`Za??4,P-"'7. ).m
 *    this list of conditions and the            ]d2e)Q(<Q(  ?94   b-  LQ/
 *    following disclaimer in the                <B!</]C)d_, '(<' .f. =C+m
 *    documentation and/or other materials      .Z!=J ]e []('-4f _ ) -.)m]'
 *    provided with the distribution.          .w[5]' _[ /.)_-"+?   _/ <W"
 * 3. Neither the name of Guichan nor the      :$we` _! + _/ .        j?
 *    names of its contributors may be used     =3)= _f  (_yQmWW$#(    "
 *    to endorse or promote products derived     -   W,  sQQQQmZQ#Wwa]..
 *    from this software without specific        (js, \[QQW$QWW#?!V"".
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 *                                                 -]n w/ '         [.
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT       )/ )/           !
 * HOLDERS AND CONTRIBUTORS "AS IS" AND ANY         <  (; sac    ,    '
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING,               ]^ .-  %
 * BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF            c <   r
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 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE          5%  )P'-3L
 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR        _bQf` y`..)a
 * ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,          ,J?4P'.P"_(\?d'.,
 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES               _Pa,)!f/<[]/  ?"
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT      _2-..:. .r+_,.. .
 * OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,     ?a.<%"'  " -'.a_ _,
 * 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.
 */

/*
 * For comments regarding functions please see the header file.
 */
#include "stratagus.h"

#include "database/preferences.h"
#include "guichan/exception.h"
#include "guichan/widgets/scrollarea.h"

namespace gcn
{
    ScrollArea::ScrollArea()
    {
        mVScroll = 0;
        mHScroll = 0;
        mHPolicy = SHOW_AUTO;
        mVPolicy = SHOW_AUTO;
        mScrollbarWidth = (12 * preferences::get()->get_scale_factor()).to_int();
        mContent = nullptr;
        mUpButtonPressed = false;
        mDownButtonPressed = false;
        mLeftButtonPressed = false;
        mRightButtonPressed = false;
        mVerticalMarkerPressed = false;
        mVerticalMarkerMousePosition = 0;
        mHorizontalMarkerPressed = false;
        mHorizontalMarkerMousePosition = 0;

        addMouseListener(this);
    }

    ScrollArea::ScrollArea(Widget *content)
    {
        mVScroll = 0;
        mHScroll = 0;
        mHPolicy = SHOW_AUTO;
        mVPolicy = SHOW_AUTO;
        mScrollbarWidth = (12 * preferences::get()->get_scale_factor()).to_int();
        mContent = nullptr;
        mUpButtonPressed = false;
        mDownButtonPressed = false;
        mLeftButtonPressed = false;
        mRightButtonPressed = false;
        mVerticalMarkerPressed = false;
        mVerticalMarkerMousePosition = 0;
        mHorizontalMarkerPressed = false;
        mHorizontalMarkerMousePosition = 0;

        setContent(content);
        addMouseListener(this);
    }

    ScrollArea::ScrollArea(Widget *content, unsigned int hPolicy, unsigned int vPolicy)
    {
        mVScroll = 0;
        mHScroll = 0;
        mHPolicy = hPolicy;
        mVPolicy = vPolicy;
        mScrollbarWidth = (12 * preferences::get()->get_scale_factor()).to_int();
        mContent = nullptr;
        mUpButtonPressed = false;
        mDownButtonPressed = false;
        mLeftButtonPressed = false;
        mRightButtonPressed = false;
        mVerticalMarkerPressed = false;
        mVerticalMarkerMousePosition = 0;
        mHorizontalMarkerPressed = false;
        mHorizontalMarkerMousePosition = 0;

        setContent(content);
        addMouseListener(this);
    }

    ScrollArea::~ScrollArea()
    {
        setContent(nullptr);
    }

    void ScrollArea::setContent(Widget* widget)
    {
        if (mContent != nullptr)
        {
            mContent->_setFocusHandler(nullptr);
            mContent->_setParent(nullptr);
        }

        mContent = widget;

        if (mContent != nullptr)
        {
            mContent->_setFocusHandler(_getFocusHandler());
            mContent->_setParent(this);
        }

        checkPolicies();
    }

    Widget* ScrollArea::getContent()
    {
        return mContent;
    }

    void ScrollArea::setHorizontalScrollPolicy(unsigned int hPolicy)
    {
        mHPolicy = hPolicy;
        checkPolicies();
    }

    unsigned int ScrollArea::getHorizontalScrollPolicy()
    {
        return mHPolicy;
    }

    void ScrollArea::setVerticalScrollPolicy(unsigned int vPolicy)
    {
        mVPolicy = vPolicy;
        checkPolicies();
    }

    unsigned int ScrollArea::getVerticalScrollPolicy()
    {
        return mVPolicy;
    }

    void ScrollArea::setScrollPolicy(unsigned int hPolicy, unsigned int vPolicy)
    {
        mHPolicy = hPolicy;
        mVPolicy = vPolicy;
        checkPolicies();
    }

    void ScrollArea::setVerticalScrollAmount(int vScroll)
    {
        int max = getVerticalMaxScroll();

        mVScroll = vScroll;

        if (vScroll > max)
        {
            mVScroll = max;
        }

        if (vScroll < 0)
        {
            mVScroll = 0;
        }
    }

    int ScrollArea::getVerticalScrollAmount()
    {
        return mVScroll;
    }

    void ScrollArea::setHorizontalScrollAmount(int hScroll)
    {
        int max = getHorizontalMaxScroll();

        mHScroll = hScroll;

        if (hScroll > max)
        {
            mHScroll = max;
        }
        else if (hScroll < 0)
        {
            mHScroll = 0;
        }
    }

    int ScrollArea::getHorizontalScrollAmount()
    {
        return mHScroll;
    }

    void ScrollArea::setScrollAmount(int hScroll, int vScroll)
    {
        setHorizontalScrollAmount(hScroll);
        setVerticalScrollAmount(vScroll);
    }

    int ScrollArea::getHorizontalMaxScroll()
    {
        checkPolicies();

        if (mContent == nullptr)
        {
            return 0;
        }

        int value = mContent->getWidth() - getContentDimension().width + 2 * mContent->getBorderSize();

        if (value < 0)
        {
            return 0;
        }

        return value;
    }

    int ScrollArea::getVerticalMaxScroll()
    {
        checkPolicies();

        if (mContent == nullptr)
        {
            return 0;
        }

        int value;

        value = mContent->getHeight() - getContentDimension().height + 2 * mContent->getBorderSize();

        if (value < 0)
        {
            return 0;
        }

        return value;
    }

    void ScrollArea::setScrollbarWidth(int width)
    {
        if (width > 0)
        {
            mScrollbarWidth = width;
        }
        else
        {
            throw std::runtime_error("Width should be greater than 0.");
        }
    }

    int ScrollArea::getScrollbarWidth()
    {
        return mScrollbarWidth;
    }

    void ScrollArea::_setFocusHandler(FocusHandler* focusHandler)
    {
        BasicContainer::_setFocusHandler(focusHandler);

        if (mContent)
        {
            mContent->_setFocusHandler(focusHandler);
        }
    }

    void ScrollArea::_mouseInputMessage(const MouseInput &mouseInput)
    {
        BasicContainer::_mouseInputMessage(mouseInput);

        if (getContentDimension().isPointInRect(mouseInput.x, mouseInput.y))
        {
            if (mContent != nullptr)
            {
                if (!mContent->hasMouse())
                {
                    mContent->_mouseInMessage();
                }

                MouseInput mi = mouseInput;

                mi.x -= mContent->getX();
                mi.y -= mContent->getY();

                mContent->_mouseInputMessage(mi);
            }
        }
        else if (mContent && mContent->hasMouse())
        {
            mContent->_mouseOutMessage();
        }
    }

    void ScrollArea::_mouseOutMessage()
    {
        if (mContent && mContent->hasMouse())
        {
            mContent->_mouseOutMessage();
        }

        BasicContainer::_mouseOutMessage();
    }

    void ScrollArea::mousePress(int x, int y, int)
    {
        if (getUpButtonDimension().isPointInRect(x, y))
        {
            setVerticalScrollAmount(getVerticalScrollAmount() - 10);
            mUpButtonPressed = true;
        }
        else if (getDownButtonDimension().isPointInRect(x, y))
        {
            setVerticalScrollAmount(getVerticalScrollAmount() + 10);
            mDownButtonPressed = true;
        }
        else if (getLeftButtonDimension().isPointInRect(x, y))
        {
            setHorizontalScrollAmount(getHorizontalScrollAmount() - 10);
            mLeftButtonPressed = true;
        }
        else if (getRightButtonDimension().isPointInRect(x, y))
        {
            setHorizontalScrollAmount(getHorizontalScrollAmount() + 10);
            mRightButtonPressed = true;
        }
        else if (getVerticalMarkerDimension().isPointInRect(x, y))
        {
            mVerticalMarkerPressed = true;
            mVerticalMarkerMousePosition = y - getVerticalMarkerDimension().y;
        }
        else if (getHorizontalMarkerDimension().isPointInRect(x, y))
        {
            mHorizontalMarkerPressed = true;
            mHorizontalMarkerMousePosition = x - getHorizontalMarkerDimension().x;
        }
    }

    void ScrollArea::mouseRelease(int)
    {
        mUpButtonPressed = false;
        mDownButtonPressed = false;
        mLeftButtonPressed = false;
        mRightButtonPressed = false;
        mVerticalMarkerPressed = false;
        mHorizontalMarkerPressed = false;
    }

    void ScrollArea::mouseMotion(int x, int y)
    {
        if (mVerticalMarkerPressed)
        {
            int pos = y - getVerticalBarDimension().y  - mVerticalMarkerMousePosition;
            int length = getVerticalMarkerDimension().height;

            Rectangle barDim = getVerticalBarDimension();

            if ((barDim.height - length) > 0)
            {
                setVerticalScrollAmount((getVerticalMaxScroll() * pos)
                                        / (barDim.height - length));
            }
            else
            {
                setVerticalScrollAmount(0);
            }
            setDirty(true);
        }
        if (mHorizontalMarkerPressed)
        {
            int pos = x - getHorizontalBarDimension().x  - mHorizontalMarkerMousePosition;
            int length = getHorizontalMarkerDimension().width;

            Rectangle barDim = getHorizontalBarDimension();

            if ((barDim.width - length) > 0)
            {
                setHorizontalScrollAmount((getHorizontalMaxScroll() * pos)
                                          / (barDim.width - length));
            }
            else
            {
                setHorizontalScrollAmount(0);
            }
            setDirty(true);
        }
    }

    void ScrollArea::draw(Graphics *graphics, std::vector<std::function<void(renderer *)>> &render_commands)
    {
        graphics->setColor(getBackgroundColor());
        graphics->fillRectangle(getContentDimension(), render_commands);
#if 0
        int alpha = getBaseColor().a;
        Color highlightColor = getBaseColor() + 0x303030;
        highlightColor.a = alpha;
        Color shadowColor = getBaseColor() - 0x303030;
        shadowColor.a = alpha;
#endif
        if (mVBarVisible)
        {
            drawUpButton(graphics, render_commands);
            drawDownButton(graphics, render_commands);
            drawVBar(graphics, render_commands);
            drawVMarker(graphics, render_commands);
        }

        if (mHBarVisible)
        {
            drawLeftButton(graphics, render_commands);
            drawRightButton(graphics, render_commands);
            drawHBar(graphics, render_commands);
            drawHMarker(graphics, render_commands);
        }

        if (mHBarVisible && mVBarVisible)
        {
            graphics->setColor(getBaseColor());
            graphics->fillRectangle(Rectangle(getWidth() - mScrollbarWidth,
                                              getHeight() - mScrollbarWidth,
                                              mScrollbarWidth,
                                              mScrollbarWidth), render_commands);
        }

        if (mContent)
        {
            Rectangle contdim = mContent->getDimension();
            graphics->pushClipArea(getContentDimension());

            if (mContent->getBorderSize() > 0)
            {
                Rectangle rec = mContent->getDimension();
                rec.x -= mContent->getBorderSize();
                rec.y -= mContent->getBorderSize();
                rec.width += 2 * mContent->getBorderSize();
                rec.height += 2 * mContent->getBorderSize();
                graphics->pushClipArea(rec);
                mContent->drawBorder(graphics, render_commands);
                graphics->popClipArea();
            }

            graphics->pushClipArea(contdim);
            mContent->draw(graphics, render_commands);
            graphics->popClipArea();
            graphics->popClipArea();
        }
    }

    void ScrollArea::drawBorder(Graphics* graphics, std::vector<std::function<void(renderer *)>> &render_commands)
    {
        Color faceColor = getBaseColor();
        Color highlightColor, shadowColor;
        int alpha = getBaseColor().a;
        int width = getWidth() + getBorderSize() * 2 - 1;
        int height = getHeight() + getBorderSize() * 2 - 1;
        highlightColor = faceColor + 0x303030;
        highlightColor.a = alpha;
        shadowColor = faceColor - 0x303030;
        shadowColor.a = alpha;

        unsigned int i;
        for (i = 0; i < getBorderSize(); ++i)
        {
            graphics->setColor(shadowColor);
            graphics->drawLine(i,i, width - i, i, render_commands);
            graphics->drawLine(i,i + 1, i, height - i - 1, render_commands);
            graphics->setColor(highlightColor);
            graphics->drawLine(width - i,i + 1, width - i, height - i, render_commands);
            graphics->drawLine(i,height - i, width - i - 1, height - i, render_commands);
        }
    }

    void ScrollArea::drawHBar(Graphics* graphics, std::vector<std::function<void(renderer *)>> &render_commands)
    {
        Rectangle dim = getHorizontalBarDimension();

        graphics->pushClipArea(dim);

        int alpha = getBaseColor().a;
        Color trackColor = getBaseColor() - 0x101010;
        trackColor.a = alpha;
        Color shadowColor = getBaseColor() - 0x303030;
        shadowColor.a = alpha;

        graphics->setColor(trackColor);
        graphics->fillRectangle(Rectangle(0, 0, dim.width, dim.height), render_commands);

        graphics->setColor(shadowColor);
        graphics->drawLine(0, 0, dim.width, 0, render_commands);

        graphics->popClipArea();
    }

    void ScrollArea::drawVBar(Graphics* graphics, std::vector<std::function<void(renderer *)>> &render_commands)
    {
        Rectangle dim = getVerticalBarDimension();

        graphics->pushClipArea(dim);

        int alpha = getBaseColor().a;
        Color trackColor = getBaseColor() - 0x101010;
        trackColor.a = alpha;
        Color shadowColor = getBaseColor() - 0x303030;
        shadowColor.a = alpha;

        graphics->setColor(trackColor);
        graphics->fillRectangle(Rectangle(0, 0, dim.width, dim.height), render_commands);

        graphics->setColor(shadowColor);
        graphics->drawLine(0, 0, 0, dim.height, render_commands);

        graphics->popClipArea();
    }

    void ScrollArea::drawUpButton(Graphics* graphics, std::vector<std::function<void(renderer *)>> &render_commands)
    {
        Rectangle dim = getUpButtonDimension();
        graphics->pushClipArea(dim);

        Color highlightColor;
        Color shadowColor;
        Color faceColor;
        int offset;
        int alpha = getBaseColor().a;

        if (mUpButtonPressed)
        {
            faceColor = getBaseColor() - 0x303030;
            faceColor.a = alpha;
            highlightColor = faceColor - 0x303030;
            highlightColor.a = alpha;
            shadowColor = getBaseColor();
            shadowColor.a = alpha;

            offset = 1;
        }
        else
        {
            faceColor = getBaseColor();
            faceColor.a = alpha;
            highlightColor = faceColor + 0x303030;
            highlightColor.a = alpha;
            shadowColor = faceColor - 0x303030;
            shadowColor.a = alpha;

            offset = 0;
        }

        graphics->setColor(faceColor);
        graphics->fillRectangle(Rectangle(0, 0, dim.width, dim.height), render_commands);

        graphics->setColor(highlightColor);
        graphics->drawLine(0, 0, dim.width - 1, 0, render_commands);
        graphics->drawLine(0, 1, 0, dim.height - 1, render_commands);

        graphics->setColor(shadowColor);
        graphics->drawLine(dim.width - 1, 0, dim.width - 1, dim.height - 1, render_commands);
        graphics->drawLine(1, dim.height - 1, dim.width - 1, dim.height - 1, render_commands);

        graphics->setColor(getForegroundColor());

        int i;
        int w = dim.height / 2;
        int h = w / 2 + 2;
        for (i = 0; i < w / 2; ++i)
        {
            graphics->drawLine(w - i + offset,
                               i + h + offset,
                               w + i + offset,
                               i + h + offset, render_commands);
        }

        graphics->popClipArea();
    }

    void ScrollArea::drawDownButton(Graphics* graphics, std::vector<std::function<void(renderer *)>> &render_commands)
    {
        Rectangle dim = getDownButtonDimension();
        graphics->pushClipArea(dim);

        Color highlightColor;
        Color shadowColor;
        Color faceColor;
        int offset;
        int alpha = getBaseColor().a;

        if (mDownButtonPressed)
        {
            faceColor = getBaseColor() - 0x303030;
            faceColor.a = alpha;
            highlightColor = faceColor - 0x303030;
            highlightColor.a = alpha;
            shadowColor = getBaseColor();
            shadowColor.a = alpha;

            offset = 1;
        }
        else
        {
            faceColor = getBaseColor();
            faceColor.a = alpha;
            highlightColor = faceColor + 0x303030;
            highlightColor.a = alpha;
            shadowColor = faceColor - 0x303030;
            shadowColor.a = alpha;

            offset = 0;
        }

        graphics->setColor(faceColor);
        graphics->fillRectangle(Rectangle(0, 0, dim.width, dim.height), render_commands);

        graphics->setColor(highlightColor);
        graphics->drawLine(0, 0, dim.width - 1, 0, render_commands);
        graphics->drawLine(0, 1, 0, dim.height - 1, render_commands);

        graphics->setColor(shadowColor);
        graphics->drawLine(dim.width - 1, 0, dim.width - 1, dim.height - 1, render_commands);
        graphics->drawLine(1, dim.height - 1, dim.width - 1, dim.height - 1, render_commands);

        graphics->setColor(getForegroundColor());

        int i;
        int w = dim.height / 2;
        int h = w + 1;
        for (i = 0; i < w / 2; ++i)
        {
            graphics->drawLine(w - i + offset,
                               -i + h + offset,
                               w + i + offset,
                               -i + h + offset, render_commands);
        }

        graphics->popClipArea();
    }

    void ScrollArea::drawLeftButton(Graphics* graphics, std::vector<std::function<void(renderer *)>> &render_commands)
    {
        Rectangle dim = getLeftButtonDimension();
        graphics->pushClipArea(dim);

        Color highlightColor;
        Color shadowColor;
        Color faceColor;
        int offset;
        int alpha = getBaseColor().a;

        if (mLeftButtonPressed)
        {
            faceColor = getBaseColor() - 0x303030;
            faceColor.a = alpha;
            highlightColor = faceColor - 0x303030;
            highlightColor.a = alpha;
            shadowColor = getBaseColor();
            shadowColor.a = alpha;

            offset = 1;
        }
        else
        {
            faceColor = getBaseColor();
            faceColor.a = alpha;
            highlightColor = faceColor + 0x303030;
            highlightColor.a = alpha;
            shadowColor = faceColor - 0x303030;
            shadowColor.a = alpha;

            offset = 0;
        }

        graphics->setColor(faceColor);
        graphics->fillRectangle(Rectangle(0, 0, dim.width, dim.height), render_commands);

        graphics->setColor(highlightColor);
        graphics->drawLine(0, 0, dim.width - 1, 0, render_commands);
        graphics->drawLine(0, 1, 0, dim.height - 1, render_commands);

        graphics->setColor(shadowColor);
        graphics->drawLine(dim.width - 1, 0, dim.width - 1, dim.height - 1, render_commands);
        graphics->drawLine(1, dim.height - 1, dim.width - 1, dim.height - 1, render_commands);

        graphics->setColor(getForegroundColor());

        int i;
        int w = dim.width / 2;
        int h = w - 2;
        for (i = 0; i < w / 2; ++i)
        {
            graphics->drawLine(i + h + offset,
                               w - i + offset,
                               i + h + offset,
                               w + i + offset, render_commands);
        }

        graphics->popClipArea();
    }

    void ScrollArea::drawRightButton(Graphics* graphics, std::vector<std::function<void(renderer *)>> &render_commands)
    {
        Rectangle dim = getRightButtonDimension();
        graphics->pushClipArea(dim);

        Color highlightColor;
        Color shadowColor;
        Color faceColor;
        int offset;
        int alpha = getBaseColor().a;

        if (mRightButtonPressed)
        {
            faceColor = getBaseColor() - 0x303030;
            faceColor.a = alpha;
            highlightColor = faceColor - 0x303030;
            highlightColor.a = alpha;
            shadowColor = getBaseColor();
            shadowColor.a = alpha;

            offset = 1;
        }
        else
        {
            faceColor = getBaseColor();
            faceColor.a = alpha;
            highlightColor = faceColor + 0x303030;
            highlightColor.a = alpha;
            shadowColor = faceColor - 0x303030;
            shadowColor.a = alpha;

            offset = 0;
        }

        graphics->setColor(faceColor);
        graphics->fillRectangle(Rectangle(0, 0, dim.width, dim.height), render_commands);

        graphics->setColor(highlightColor);
        graphics->drawLine(0, 0, dim.width - 1, 0, render_commands);
        graphics->drawLine(0, 1, 0, dim.height - 1, render_commands);

        graphics->setColor(shadowColor);
        graphics->drawLine(dim.width - 1, 0, dim.width - 1, dim.height - 1, render_commands);
        graphics->drawLine(1, dim.height - 1, dim.width - 1, dim.height - 1, render_commands);

        graphics->setColor(getForegroundColor());

        int i;
        int w = dim.width / 2;
        int h = w + 1;
        for (i = 0; i < w / 2; ++i)
        {
            graphics->drawLine(-i + h + offset,
                               w - i + offset,
                               -i + h + offset,
                               w + i + offset, render_commands);
        }

        graphics->popClipArea();
    }

    void ScrollArea::drawVMarker(Graphics* graphics, std::vector<std::function<void(renderer *)>> &render_commands)
    {
        Rectangle dim = getVerticalMarkerDimension();
        graphics->pushClipArea(dim);

        int alpha = getBaseColor().a;
        Color faceColor = getBaseColor();
        faceColor.a = alpha;
        Color highlightColor = faceColor + 0x303030;
        highlightColor.a = alpha;
        Color shadowColor = faceColor - 0x303030;
        shadowColor.a = alpha;

        graphics->setColor(faceColor);
        graphics->fillRectangle(Rectangle(1, 1, dim.width - 1, dim.height - 1), render_commands);

        graphics->setColor(highlightColor);
        graphics->drawLine(0, 0, dim.width - 1, 0, render_commands);
        graphics->drawLine(0, 1, 0, dim.height - 1, render_commands);

        graphics->setColor(shadowColor);
        graphics->drawLine(1, dim.height - 1, dim.width - 1, dim.height - 1, render_commands);
        graphics->drawLine(dim.width - 1, 0, dim.width - 1, dim.height - 1, render_commands);

        graphics->popClipArea();
    }

    void ScrollArea::drawHMarker(Graphics* graphics, std::vector<std::function<void(renderer *)>> &render_commands)
    {
        Rectangle dim = getHorizontalMarkerDimension();
        graphics->pushClipArea(dim);

        int alpha = getBaseColor().a;
        Color faceColor = getBaseColor();
        faceColor.a = alpha;
        Color highlightColor = faceColor + 0x303030;
        highlightColor.a = alpha;
        Color shadowColor = faceColor - 0x303030;
        shadowColor.a = alpha;

        graphics->setColor(faceColor);
        graphics->fillRectangle(Rectangle(1, 1, dim.width - 1, dim.height - 1), render_commands);

        graphics->setColor(highlightColor);
        graphics->drawLine(0, 0, dim.width - 1, 0, render_commands);
        graphics->drawLine(0, 1, 0, dim.height - 1, render_commands);

        graphics->setColor(shadowColor);
        graphics->drawLine(1, dim.height - 1, dim.width - 1, dim.height - 1, render_commands);
        graphics->drawLine(dim.width - 1, 0, dim.width - 1, dim.height - 1, render_commands);

        graphics->popClipArea();
    }

    void ScrollArea::logic()
    {
        checkPolicies();

        setVerticalScrollAmount(getVerticalScrollAmount());
        setHorizontalScrollAmount(getHorizontalScrollAmount());

        if (mContent != nullptr)
        {
            mContent->setPosition(-mHScroll + getContentDimension().x + mContent->getBorderSize(),
                                  -mVScroll + getContentDimension().y + mContent->getBorderSize());

            mContent->logic();
        }
    }

    void ScrollArea::moveToTop(Widget* widget)
    {
        if (widget == mContent)
        {
            if (getParent())
            {
                getParent()->moveToTop(this);
            }
        }
        else
        {
            throw std::runtime_error("Only a ScrollArea's content may be moved to top.");
        }
    }

    void ScrollArea::moveToBottom(Widget* widget)
    {
        if (widget == mContent)
        {
            if (getParent())
            {
                getParent()->moveToBottom(this);
            }
        }
        else
        {
            throw std::runtime_error("Only a ScrollArea's content may be moved to bottom.");
        }
    }

    void ScrollArea::_announceDeath(Widget *widget)
    {
        if (widget == mContent)
        {
            mContent = nullptr;
            checkPolicies();
        }
        else
        {
            throw std::runtime_error("Called by not-child.");
        }
    }

    void ScrollArea::getDrawSize(int& width, int& height, Widget* widget)
    {
        if (mContent == widget)
        {
            width = getContentDimension().width;
            height = getContentDimension().height;
        }
        else
        {
            throw std::runtime_error("Widget not in scrollarea.");
        }
    }

    void ScrollArea::drawContent(Graphics* graphics, std::vector<std::function<void(renderer *)>> &render_commands)
    {
        if (mContent)
        {
            mContent->draw(graphics, render_commands);
        }
    }

    void ScrollArea::checkPolicies()
    {
        int w = getWidth();
        int h = getHeight();

        mHBarVisible = false;
        mVBarVisible = false;


        if (!mContent)
        {
            mHBarVisible = (mHPolicy == SHOW_ALWAYS);
            mVBarVisible = (mVPolicy == SHOW_ALWAYS);
            return;
        }

        if (mHPolicy == SHOW_AUTO &&
            mVPolicy == SHOW_AUTO)
        {
            if (mContent->getWidth() <= w
                && mContent->getHeight() <= h)
            {
                mHBarVisible = false;
                mVBarVisible = false;
            }

            if (mContent->getWidth() > w)
            {
                mHBarVisible = true;
            }

            if ((mContent->getHeight() > h)
                || (mHBarVisible && mContent->getHeight() > h - mScrollbarWidth))
            {
                mVBarVisible = true;
            }

            if (mVBarVisible && mContent->getWidth() > w - mScrollbarWidth)
            {
                mHBarVisible = true;
            }

            return;
        }

        switch (mHPolicy)
        {
          case SHOW_NEVER:
              mHBarVisible = false;
              break;

          case SHOW_ALWAYS:
              mHBarVisible = true;
              break;

          case SHOW_AUTO:
              if (mVPolicy == SHOW_NEVER)
              {
                  mHBarVisible = mContent->getWidth() > w;
              }
              else // (mVPolicy == SHOW_ALWAYS)
              {
                  mHBarVisible = mContent->getWidth() > w - mScrollbarWidth;
              }
              break;

          default:
              throw std::runtime_error("Horizontal scroll policy invalid.");
        }

        switch (mVPolicy)
        {
          case SHOW_NEVER:
              mVBarVisible = false;
              break;

          case SHOW_ALWAYS:
              mVBarVisible = true;
              break;

          case SHOW_AUTO:
              if (mHPolicy == SHOW_NEVER)
              {
                  mVBarVisible = mContent->getHeight() > h;
              }
              else // (mHPolicy == SHOW_ALWAYS)
              {
                  mVBarVisible = mContent->getHeight() > h - mScrollbarWidth;
              }
              break;
          default:
              throw std::runtime_error("Vertical scroll policy invalid.");
        }
    }

    Rectangle ScrollArea::getUpButtonDimension()
    {
        if (!mVBarVisible)
        {
            return Rectangle(0, 0, 0, 0);
        }

        return Rectangle(getWidth() - mScrollbarWidth,
                         0,
                         mScrollbarWidth,
                         mScrollbarWidth);
    }

    Rectangle ScrollArea::getDownButtonDimension()
    {
        if (!mVBarVisible)
        {
            return Rectangle(0, 0, 0, 0);
        }

        if (mVBarVisible && mHBarVisible)
        {
            return Rectangle(getWidth() - mScrollbarWidth,
                             getHeight() - mScrollbarWidth*2,
                             mScrollbarWidth,
                             mScrollbarWidth);
        }

        return Rectangle(getWidth() - mScrollbarWidth,
                         getHeight() - mScrollbarWidth,
                         mScrollbarWidth,
                         mScrollbarWidth);
    }

    Rectangle ScrollArea::getLeftButtonDimension()
    {
        if (!mHBarVisible)
        {
            return Rectangle(0, 0, 0, 0);
        }

        return Rectangle(0,
                         getHeight() - mScrollbarWidth,
                         mScrollbarWidth,
                         mScrollbarWidth);
    }

    Rectangle ScrollArea::getRightButtonDimension()
    {
        if (!mHBarVisible)
        {
            return Rectangle(0, 0, 0, 0);
        }

        if (mVBarVisible && mHBarVisible)
        {
            return Rectangle(getWidth() - mScrollbarWidth*2,
                             getHeight() - mScrollbarWidth,
                             mScrollbarWidth,
                             mScrollbarWidth);
        }

        return Rectangle(getWidth() - mScrollbarWidth,
                         getHeight() - mScrollbarWidth,
                         mScrollbarWidth,
                         mScrollbarWidth);
    }

    Rectangle ScrollArea::getContentDimension()
    {
        if (mVBarVisible && mHBarVisible)
        {
            return Rectangle(0, 0, getWidth() - mScrollbarWidth,
                             getHeight() - mScrollbarWidth);
        }

        if (mVBarVisible)
        {
            return Rectangle(0, 0, getWidth() - mScrollbarWidth, getHeight());
        }

        if (mHBarVisible)
        {
            return Rectangle(0, 0, getWidth(), getHeight() - mScrollbarWidth);
        }

        return Rectangle(0, 0, getWidth(), getHeight());
    }

    Rectangle ScrollArea::getVerticalBarDimension()
    {
        if (!mVBarVisible)
        {
            return Rectangle(0, 0, 0, 0);
        }

        if (mHBarVisible)
        {
            return Rectangle(getWidth() - mScrollbarWidth,
                             getUpButtonDimension().height,
                             mScrollbarWidth,
                             getHeight()
                             - getUpButtonDimension().height
                             - getDownButtonDimension().height
                             - mScrollbarWidth);
        }

        return Rectangle(getWidth() - mScrollbarWidth,
                         getUpButtonDimension().height,
                         mScrollbarWidth,
                         getHeight()
                         - getUpButtonDimension().height
                         - getDownButtonDimension().height);
    }

    Rectangle ScrollArea::getHorizontalBarDimension()
    {
        if (!mHBarVisible)
        {
            return Rectangle(0, 0, 0, 0);
        }

        if (mVBarVisible)
        {
            return Rectangle(getLeftButtonDimension().width,
                             getHeight() - mScrollbarWidth,
                             getWidth()
                             - getLeftButtonDimension().width
                             - getRightButtonDimension().width
                             - mScrollbarWidth,
                             mScrollbarWidth);
        }

        return Rectangle(getLeftButtonDimension().width,
                         getHeight() - mScrollbarWidth,
                         getWidth()
                         - getLeftButtonDimension().width
                         - getRightButtonDimension().width,
                         mScrollbarWidth);
    }

    Rectangle ScrollArea::getVerticalMarkerDimension()
    {
        if (!mVBarVisible)
        {
            return Rectangle(0, 0, 0, 0);
        }

        int length, pos;
        Rectangle barDim = getVerticalBarDimension();

        if (mContent && mContent->getHeight() != 0)
        {
            length = (barDim.height * getContentDimension().height)
                / mContent->getHeight();
        }
        else
        {
            length = barDim.height;
        }

        if (length < mScrollbarWidth)
        {
            length = mScrollbarWidth;
        }

        if (length > barDim.height)
        {
            length = barDim.height;
        }

        if (getVerticalMaxScroll() != 0)
        {
            pos = ((barDim.height - length) * getVerticalScrollAmount())
                / getVerticalMaxScroll();
        }
        else
        {
            pos = 0;
        }

        return Rectangle(barDim.x, barDim.y + pos, mScrollbarWidth, length);
    }

    Rectangle ScrollArea::getHorizontalMarkerDimension()
    {
        if (!mHBarVisible)
        {
            return Rectangle(0, 0, 0, 0);
        }

        int length, pos;
        Rectangle barDim = getHorizontalBarDimension();

        if (mContent && mContent->getWidth() != 0)
        {
            length = (barDim.width * getContentDimension().width)
                / mContent->getWidth();
        }
        else
        {
            length = barDim.width;
        }

        if (length < mScrollbarWidth)
        {
            length = mScrollbarWidth;
        }

        if (length > barDim.width)
        {
            length = barDim.width;
        }

        if (getHorizontalMaxScroll() != 0)
        {
            pos = ((barDim.width - length) * getHorizontalScrollAmount())
                / getHorizontalMaxScroll();
        }
        else
        {
            pos = 0;
        }

        return Rectangle(barDim.x + pos, barDim.y, length, mScrollbarWidth);
    }

    void ScrollArea::scrollToRectangle(const Rectangle& rectangle)
    {
        Rectangle contentDim = getContentDimension();

        if (rectangle.x + rectangle.width
            > getHorizontalScrollAmount() + contentDim.width)
        {
            setHorizontalScrollAmount(rectangle.x + rectangle.width - contentDim.width);
        }

        if (rectangle.y + rectangle.height
            > getVerticalScrollAmount() + contentDim.height)
        {
            setVerticalScrollAmount(rectangle.y + rectangle.height - contentDim.height);
        }

        if (rectangle.x < getHorizontalScrollAmount())
        {
            setHorizontalScrollAmount(rectangle.x);
        }

        if (rectangle.y < getVerticalScrollAmount())
        {
            setVerticalScrollAmount(rectangle.y);
        }
    }

    void ScrollArea::mouseWheelUp(int, int)
    {
        if (hasMouse())
        {
            setVerticalScrollAmount(getVerticalScrollAmount() - getContentDimension().height / 8);
        }
    }

    void ScrollArea::mouseWheelDown(int, int)
    {
        if (hasMouse())
        {
            setVerticalScrollAmount(getVerticalScrollAmount() + getContentDimension().height / 8);
        }
    }
}

/*
 * Wow! This is a looooong source file. 1291 lines!
 */
