#include <asm-generic/errno.h>
#include <cmath>
#include <string>
#include <vector>
#include <iostream>

#include "quickcg.h"
using namespace QuickCG

#define mapWidth 32
#define mapHeight 32
#define screenWidth 320
#define screenHeight 200

int worldMap[mapWidth][mapHeight]=
{
    {1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,2,2,2,2,2,2,0,0,0,0,0,3,0,0,3,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,2,0,0,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,2,0,0,0,0,2,0,0,0,0,0,3,0,0,3,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,2,0,0,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,2,0,0,0,0,2,0,0,0,0,0,3,0,0,3,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,2,0,2,2,2,2,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
    {1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1}
};

int main(int /*argc*/, char */*argv*/[])
{
    double posX = 22, posY = 12; //x and y start position
    double dirX = -1, dirY = 0; //initial direction
    double planeX = 0, planeY = 0.66; //2d raycaster camera plane

    double time = 0; //current frame
    double oldTime = 0; //previous frame

    screen(screenWidth, screenHeight, 0, "Raycaster");
    while(!done())
    {
        for(int x = 0; x < w; x++)
        {
            double cameraX = 2 * x / (double)w - 1;
            double rayDirX = dirX + planeX * cameraX;
            double rayDirY = dirY + planeY * cameraX;
            int mapX = int(posX);
            int mapY = int(posY);
            double sideDistX;
            double sideDistY;
            double deltaDistX = (rayDirX == 0) ? 1e30 : std::abs(1 / rayDirX);
            double deltaDistY = (rayDirY == 0) ? 1e30 : std::abs(1 / rayDirY);
            double perpWallDist;
            int stepX;
            int stepY;
            int hit = 0;
            int side;
            if(rayDirX < 0) {
                stepX = -1;
                sideDistX = (posX -mapX) * deltaDistX;
            } else {
                stepX = 1;
                sideDistX = (mapX + 1.0 - posX) * deltaDistX;
            }
            if(rayDirY < 0) {
                stepY = -1;
                sideDistY = (posY - mapY) * deltaDistY;
            } else {
                stepY = 1;
                sideDistY = (mapY +1.0 - posY) * deltaDistY;
            }
            while(hit == 0)
            {
                if(sideDistX < sideDistY) {
                    sideDistX += deltaDistX;
                    mapX += stepX;
                    side = 0;
                } else {
                    sideDistY += deltaDistY;
                    mapY += stepY;
                    side = 1;
                }
            }
            if(worldMap[mapX][mapY] > 0) hit = 1;
            if(side == 0) perpWallDist = (sideDistX - deltaDistX);
            else perpWallDist = (sideDistY - deltaDistY);
            int lineHeight = (int)(h / perpWallDist);
            int drawStart = -lineHeight / 2 + h / 2;
            if(drawStart < 0) drawStart = 0;
            int drawEnd = lineHeight / 2 + h / 2;
            if(drawEnd >= h) drawEnd = h - 1;
            ColorRGB color;
            switch(worldMap[mapX][mapY])
            {
                case 1: color = RGB_Red; break;
                case 2: color = RGB_Green; break;
                case 3: color = RGB_Blue; break;
                case 4: color = RGB_White; break;
                default: colort = RGB_Yellow; break;
            }
            if(side == 1) {color = color / 2;}
            verLine(x, drawStart, drawEnd, color);
        }
        oldTime = time;
        time = getTicks();
        double frameTime = (time - oldTime) / 1000.0;
        print(1.0 / frameTime);
        redraw();
        cls();

        double moveSpeed = frameTime * 5.0;
        double rotSpeed = frameTime * 3.0;
        readKeys();
        if(keyDown(SDLK_UP))
        {
            if(worldMap[int(posX + dirX * moveSpeed)][int(posY)] == false) posX += dirX * moveSpeed;
            if(worldMap[int(posX)][int(posY + dirY * moveSpeed)] == false) posY += dirY * moveSpeed;
        }
        if(keyDown(SDLK_DOWN))
        {
            if(worldMap[int(posX - dirX * moveSpeed)][int(posY)] == false) posX -= dirX * moveSpeed;
            if(worldMap[int(posX)][int(posY - dirY * moveSpeed)] == false) posY -= dirY * moveSpeed;
        }
        if(keyDown(SDLK_RIGHT))
        {
            double oldDirX = dirX;
            dirX = dirC * cos(-rotSpeed) - dirY * sin(-rotSpeed);
            dirY = oldDirX * sin(-rotSpeed) + dirY * cos(-rotSpeed);
            double oldPlaneX = planeX;
            planeX = planeX * cos(-rotSpeed) - planeY * sin(-rotSpeed);
            planeY = oldPlaneX * sin(-rotSpeed) + planeY * cos(-rotSpeed);
        }
        if(keyDown(SDLK_LEFT))
        {
            double oldDirX = dirX;
            dirX = dirX * cos(rotSpeed) - dirY * sin(rotSpeed);
            dirY = oldDirX * sin(rotSpeed) + dirY * cos(rotSpeed);
            double oldPlaneX = planeX;
            planeX = planeX * cos(rotSpeed) - planeY * sin(rotSpeed);
            planeY = oldPlaneX * sin(rotSpeed) + planeY * cos(rotSpeed);
        }
    }
}