#ifndef __C_GUI_ROUND_PROGRESS_HEADER__
#define __C_GUI_ROUND_PROGRESS_HEADER__

#include <irrlicht/IGUIElement.h>
#include <irrlicht/ITexture.h>
#include <irrlicht/IVideoDriver.h>
#include <irrlicht/SMaterial.h>
#include <irrlicht/S3DVertex.h>
#include <irrlicht/irrList.h>

/**
 * Copyright (C) <2014>
 * Ovan/Magun contact on irrlicht-fr.org or ovan@sleek-think.ovh
 *
 * This software is provided 'as-is', without any express or implied
 * warranty.  In no event will the authors be held liable for any damages
 * arising from the use of this software.
 *
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 *
 * 1. The origin of this software must not be misrepresented; you must not
 *    claim that you wrote the original software. If you use this software
 *    in a product, an acknowledgment in the product documentation would be
 *    appreciated but is not required.
 * 2. Altered source versions must be plainly marked as such, and must not be
 *    misrepresented as being the original software.
 * 3. This notice may not be removed or altered from any source distribution.
**/

namespace irr
{
    namespace gui
    {
        struct CGUIPieChartElement
        {
            public:
                CGUIPieChartElement(float from = 0.f, float to = 1.f, const video::SColor &c = {255, 255, 255, 255}, float depth = 0.f);

                void set(float from, float to);
                void setDepth(float depth = 0.f);
                void setColor(const video::SColor&);
            public:
                video::SColor clr;
                float from, to, depth;
                core::array<core::triangle3df> pos;
            private:
                void calc(float from, float to);
                core::vector3df calc(float);
            private:
                friend class CGUIPieChart;
        };
        class CGUIPieChart : public IGUIElement
        {
            public:
                CGUIPieChart(IGUIEnvironment *environment, IGUIElement *parent, const core::recti &size, s32 id = 0) noexcept;
                ~CGUIPieChart() noexcept;

                virtual void add(const CGUIPieChartElement&);
                virtual CGUIPieChartElement& get(int);
                virtual bool erase(int);
                virtual int count() const;

                virtual void setBackgroundColor(const video::SColor&);
                virtual void setBackgroundTexture(video::ITexture*);
                virtual void setForegroundTexture(video::ITexture*);

                virtual video::ITexture* getBackgroundTexture() const;
                virtual video::ITexture* getForegroundTexture() const;
                virtual video::SColor    getBackgroundColor() const;

                virtual void updateAbsolutePosition();

                virtual void draw();
            protected:
                video::IVideoDriver *driver;
                core::list<CGUIPieChartElement> item;
            private:
                video::SColor clr;
                core::array<u16> idx;
                core::array<video::S3DVertex> vtx;
                video::ITexture *bg, *fg;
                video::SMaterial mat;
        };
    }
}

#endif

#include "CGUIPieChart.h"

#include <irrlicht/IGUIEnvironment.h>
#include <irrlicht/IVideoDriver.h>
#include <irrlicht/S3DVertex.h>
#include <irrlicht/irrMath.h>
#include <irrlicht/SColor.h>
#include <iostream>

namespace irr
{
    namespace gui
    {
        CGUIPieChartElement::CGUIPieChartElement(float f, float t, const video::SColor &c, float d)
            : clr(c), depth(d)
        {
            set(f, t);
        }
        void CGUIPieChartElement::set(float f, float t)
        {
            from = f;
            to = t;
        }
        void CGUIPieChartElement::setDepth(float i)
        {
            for(int j = 0; j<pos.size(); ++j)
            {
                pos[j].pointA.Z = i;
                pos[j].pointB.Z = i;
                pos[j].pointC.Z = i;
            }
            depth = i;
        }
        void CGUIPieChartElement::setColor(const video::SColor &i)
        {
            clr = i;
        }
        core::vector3df CGUIPieChartElement::calc(float i)
        {
            core::vector3df f(0, 0, depth);

            if(i >= 0.75f && i < 1.0f)
                f.X = core::clamp((1.00f-i)*4, 0.f, 1.f);

            if(i >= 0.50f && i < 0.75f)
            {
                f.Y = core::clamp((0.75f-i)*4, 0.f, 1.f);
                f.X = 1.f;
            }

            if(i >= 0.25f && i < 0.50f)
            {
                f.Y = 1.f;
                f.X = 1.f - core::clamp((0.50f-i)*4, 0.f, 1.f);
            }

            if(i > 0.f && i <= 0.25f)
                f.Y = 1.f - core::clamp((0.25f-i)*4, 0.f, 1.f);

            return f;
        }
        void CGUIPieChartElement::calc(float from, float to)
        {
            if(to-from <= 0.0000001f)
                return;

            if(from > to || to > 1.f)
            {
                calc(from, 1.f);
                calc(0.f, to-(int)to);
                return;
            }

            float next = to;

            if(from >= 0.00f)
                next = core::min_(to, 0.25f);
            if(from >= 0.25f)
                next = core::min_(to, 0.50f);
            if(from >= 0.50f)
                next = core::min_(to, 0.75f);
            if(from >= 0.75f)
                next = core::min_(to, 1.0f);

            if(next != to)
            {
                calc(from, next);
                calc(next, to);
            }
            else
            {
                pos.push_back({
                    calc(from),
                    { 0.5f,  0.5f, depth},
                    calc(next)
                });
            }
        }
        /***************************************************/

        CGUIPieChart::CGUIPieChart(IGUIEnvironment *environment, IGUIElement *parent, const core::recti &size, s32 id) noexcept
            : IGUIElement(EGUIET_ELEMENT , environment, parent, id, size), bg(nullptr), fg(nullptr),
              driver(environment->getVideoDriver()), clr(255, 128, 128, 128)
        {
            mat.MaterialType = video::EMT_TRANSPARENT_ALPHA_CHANNEL;
            mat.BackfaceCulling = false;
        }
        CGUIPieChart::~CGUIPieChart() noexcept
        {
            if(bg) bg->drop();
            if(fg) fg->drop();
        }
        void CGUIPieChart::add(const CGUIPieChartElement& i)
        {
            item.push_back(i);
        }
        CGUIPieChartElement& CGUIPieChart::get(int i)
        {
            return *(item.begin()+i);
        }
        bool CGUIPieChart::erase(int i)
        {
            if(i >= count())
                return false;

            auto it = item.begin();
                 it += i;
            item.erase(it);

            return true;
        }
        int CGUIPieChart::count() const
        {
            return item.size();
        }
        void CGUIPieChart::setForegroundTexture(video::ITexture *f)
        {
            mat.setTexture(0, f);
            if(f) f->grab();
            if(fg) fg->drop();
            fg = f;
        }
        void CGUIPieChart::setBackgroundTexture(video::ITexture *b)
        {
            if(b) b->grab();
            if(bg) bg->drop();
            bg = b;
        }
        void CGUIPieChart::setBackgroundColor(const irr::video::SColor &i)
        {
            clr = i;
        }
        video::SColor CGUIPieChart::getBackgroundColor() const
        {
            return clr;
        }
        video::ITexture* CGUIPieChart::getForegroundTexture() const
        {
            return fg;
        }
        video::ITexture* CGUIPieChart::getBackgroundTexture() const
        {
            return bg;
        }
        void CGUIPieChart::updateAbsolutePosition()
        {
            auto size = AbsoluteRect.getSize();
            auto &start = AbsoluteRect.UpperLeftCorner;

            vtx.clear();
            idx.clear();

            for(auto &it : item)
            {
                it.pos.clear();
                it.calc(it.from, it.to);
                for(int i = 0; i<it.pos.size(); ++i)
                {
                        idx.push_back(vtx.size());
                        vtx.push_back({
                            start.X + it.pos[i].pointA.X * size.Width,
                            start.Y + it.pos[i].pointA.Y * size.Height,
                            it.pos[i].pointA.Z,
                            0.f, 0.f, 1.f, it.clr,
                            it.pos[i].pointA.X,
                            it.pos[i].pointA.Y
                        });

                        idx.push_back(vtx.size());
                        vtx.push_back({
                            start.X + it.pos[i].pointB.X * size.Width,
                            start.Y + it.pos[i].pointB.Y * size.Height,
                            it.pos[i].pointB.Z,
                            0.f, 0.f, 1.f, it.clr,
                            it.pos[i].pointB.X,
                            it.pos[i].pointB.Y
                        });

                        idx.push_back(vtx.size());
                        vtx.push_back({
                            start.X + it.pos[i].pointC.X * size.Width,
                            start.Y + it.pos[i].pointC.Y * size.Height,
                            it.pos[i].pointC.Z,
                            0.f, 0.f, 1.f, it.clr,
                            it.pos[i].pointC.X,
                            it.pos[i].pointC.Y
                        });
                }
            }
            IGUIElement::updateAbsolutePosition();
        }
        void CGUIPieChart::draw()
        {
            if(bg)
            {
                const video::SColor Colors[] = {clr, clr, clr, clr};
                core::rect<s32> sourceRect = core::rect<s32>(core::dimension2di(bg->getOriginalSize()));
                driver->draw2DImage(
                    bg, AbsoluteRect, sourceRect,
                    &AbsoluteClippingRect, Colors, true
                );
            }
            else
            {
                Environment->getSkin()->draw3DSunkenPane(
                    this, clr, true, true, AbsoluteRect, &AbsoluteClippingRect
                );
            }

            driver->setMaterial(mat);
            driver->draw2DVertexPrimitiveList(
                vtx.pointer(), vtx.size(),
                idx.pointer(), idx.size()/3,
                video::EVT_STANDARD,
                scene::EPT_TRIANGLES,
                video::EIT_16BIT
            );

            IGUIElement::draw();
        }
    }
}