// XineramaBarriers
// ----------
// Copyright (C) 2011, Timur Kristóf
//
// This X client application will create pointer barriers
// based on the Xinerama information of your current driver.
// Only works with XFixes v5 or higher and the Xorg server
// which has the pointer barriers patch.
// ----------
// 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 (at your option) 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, write to the Free Software
// Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA.

#include "barriermanager.h"
#include <iostream>
#include <algorithm>

static std::ostream &operator<<(std::ostream &os, const XineramaScreenInfo &info)
{
    return os << info.screen_number << " " << info.width << " " << info.height << " " << info.x_org << " " << info.y_org;
}

static std::vector<XineramaScreenInfo> fetchXineramaInfo(Display *d)
{
    std::vector<XineramaScreenInfo> result;
    int a;
    XineramaScreenInfo *info = XineramaQueryScreens(d, &a);
    for (int i = 0; i < a; i++)
    {
        result.push_back(info[i]);
        std::cout << info[i] << std::endl;
    }
    XFree(info);
    return result;
}

static bool compareY(const XineramaScreenInfo &i1, const XineramaScreenInfo &i2)
{
    return i1.y_org < i2.y_org;
}

static bool compareX(const XineramaScreenInfo &i1, const XineramaScreenInfo &i2)
{
    return i1.x_org < i2.x_org;
}

BarrierManager::BarrierManager(Display *d)
    : d(d)
{
    updateBarriers();
}

BarrierManager::~BarrierManager()
{
    destroyBarriers();
}

void BarrierManager::destroyBarriers()
{
    for (std::vector<PointerBarrier>::iterator i = barriers.begin(); i != barriers.end(); i++)
        XFixesDestroyPointerBarrier(d, *i);
    barriers.clear();
}

void BarrierManager::updateBarriers()
{
    destroyBarriers();
    XGetWindowAttributes(d, DefaultRootWindow(d), &attrs);
    infos = fetchXineramaInfo(d);

    std::cout << "updating barriers" << std::endl;

    for (std::vector<XineramaScreenInfo>::iterator i = infos.begin(); i != infos.end(); i++)
    {
        if (i->x_org)
        {
            // Checking left neighbours
            std::vector<XineramaScreenInfo> leftNeighbours;
            for (std::vector<XineramaScreenInfo>::iterator j = infos.begin(); j != infos.end(); j++)
                if (j->x_org + j->width == i->x_org)
                    leftNeighbours.push_back(*j);

            std::sort(leftNeighbours.begin(), leftNeighbours.end(), compareY);
            int startY = i->y_org;
            int x = i->x_org;

            // Adding barriers to the edge to the area where there are no neighbours
            for (std::vector<XineramaScreenInfo>::iterator j = leftNeighbours.begin(); j != leftNeighbours.end(); j++)
            {
                if (j->y_org > startY)
                {
                    barriers.push_back(XFixesCreatePointerBarrier(d, DefaultRootWindow(d), x, startY, x, j->y_org, BarrierPositiveX, 0, 0));
                    std::cout << "left barrier created: x=" << x << " startY=" << startY << " y=" << j->y_org + j->height << std::endl;
                }
                startY = MIN(j->y_org + j->height, i->y_org + i->height);
            }
            if (startY < i->y_org + i->height)
            {
                // Adding a barrier to the remaining area where there are no more neighbours
                barriers.push_back(XFixesCreatePointerBarrier(d, DefaultRootWindow(d), x, startY, x, i->y_org + i->height, BarrierPositiveX, 0, 0));
                std::cout << "left barrier created: x=" << x << " startY=" << startY << " y=" << i->y_org + i->height << std::endl;
            }
        }

        if (i->x_org + i->width != attrs.width)
        {
            // checking right neighbours
            std::vector<XineramaScreenInfo> rightNeighbours;
            for (std::vector<XineramaScreenInfo>::iterator j = infos.begin(); j != infos.end(); j++)
                if (i->x_org + i->width == j->x_org)
                    rightNeighbours.push_back(*j);

            std::sort(rightNeighbours.begin(), rightNeighbours.end(), compareY);
            int startY = i->y_org;
            int x = i->x_org + i->width;

            // Adding barriers to the edge to the area where there are no neighbours
            for (std::vector<XineramaScreenInfo>::iterator j = rightNeighbours.begin(); j != rightNeighbours.end(); j++)
            {
                if (j->y_org > startY)
                {
                    barriers.push_back(XFixesCreatePointerBarrier(d, DefaultRootWindow(d), x, startY, x, j->y_org, BarrierNegativeX, 0, 0));
                    std::cout << "right barrier created: x=" << x << " startY=" << startY << " y=" << j->y_org << std::endl;
                }
                startY = MIN(j->y_org + j->height, i->y_org + i->height);
            }
            if (startY < i->y_org + i->height)
            {
                // Adding a barrier to the remaining area where there are no more neighbours
                barriers.push_back(XFixesCreatePointerBarrier(d, DefaultRootWindow(d), x, startY, x, i->y_org + i->height, BarrierNegativeX, 0, 0));
                std::cout << "right barrier created: x=" << x << " startY=" << startY << " y=" << i->y_org + i->height << std::endl;
            }
        }

        if (i->y_org)
        {
            // checking top neighbours
            std::vector<XineramaScreenInfo> topNeighbours;
            for (std::vector<XineramaScreenInfo>::iterator j = infos.begin(); j != infos.end(); j++)
                if (j->y_org + j->height == i->y_org)
                    topNeighbours.push_back(*j);

            std::sort(topNeighbours.begin(), topNeighbours.end(), compareX);
            int startX = i->x_org;
            int y = i->y_org;

            // Adding barriers to the edge to the area where there are no neighbours
            for (std::vector<XineramaScreenInfo>::iterator j = topNeighbours.begin(); j != topNeighbours.end(); j++)
            {
                if (j->x_org > startX)
                {
                    barriers.push_back(XFixesCreatePointerBarrier(d, DefaultRootWindow(d), startX, y, j->x_org, y, BarrierPositiveY, 0, 0));
                    std::cout << "top barrier created: y=" << y << " startX=" << startX << " X=" << j->x_org << std::endl;
                }
                startX = MIN(j->x_org + j->width, i->x_org + i->width);
            }
            if (startX < i->x_org + i->width)
            {
                // Adding a barrier to the remaining area where there are no more neighbours
                barriers.push_back(XFixesCreatePointerBarrier(d, DefaultRootWindow(d), startX, y, i->x_org + i->width, y, BarrierPositiveY, 0, 0));
                std::cout << "top barrier created: y=" << y << " startX=" << startX << " X=" << i->x_org + i->width << std::endl;
            }
        }

        if (i->y_org + i->height != attrs.height)
        {
            // checking bottom neighbours
            std::vector<XineramaScreenInfo> bottomNeighbours;
            for (std::vector<XineramaScreenInfo>::iterator j = infos.begin(); j != infos.end(); j++)
                if (i->y_org + i->height == j->y_org)
                    bottomNeighbours.push_back(*j);

            std::sort(bottomNeighbours.begin(), bottomNeighbours.end(), compareX);
            int startX = i->x_org;
            int y = i->y_org + i->height;

            // Adding barriers to the edge to the area where there are no neighbours
            for (std::vector<XineramaScreenInfo>::iterator j = bottomNeighbours.begin(); j != bottomNeighbours.end(); j++)
            {
                if (j->x_org > startX)
                {
                    barriers.push_back(XFixesCreatePointerBarrier(d, DefaultRootWindow(d), startX, y, j->x_org, y, BarrierNegativeY, 0, 0));
                    std::cout << "bottom barrier created: y=" << y << " startX=" << startX << " X=" << j->x_org << std::endl;
                }
                startX = MIN(j->x_org + j->width, i->x_org + i->width);
            }
            if (startX < i->x_org + i->width)
            {
                // Adding a barrier to the remaining area where there are no more neighbours
                barriers.push_back(XFixesCreatePointerBarrier(d, DefaultRootWindow(d), startX, y, i->x_org + i->width, y, BarrierNegativeY, 0, 0));
                std::cout << "bottom barrier created: y=" << y << " startX=" << startX << " X=" << i->x_org + i->width << std::endl;
            }
        }
    }
}