#include <iostream>
#include <chrono>
using namespace std;
#include <Windows.h>

int nScreenWidth = 120;
int nScreenHeight = 40;

float fPlayerX = 8.0f;
float fPlayerY = 8.0f;
float fPlayerA = 0.0f;

int nMapHeight = 16;
int nMapWidth = 16;

float fFOV = 3.14159 / 4.0;
float fDepth = 16.0f;

int main()
{
    wchar_t *screen = new wchar_t[nScreenWidth*nScreenHeight];
    HANDLE hConsole = CreateConsoleScreenBuffer(GENERIC_READ | GENERIC_WRITE, 0, NULL, CONSOLE_TEXTMODE_BUFFER, NULL);
    SetConsoleActiveScreenBuffer(hConsole);
    DWORD dwBytesWritten = 0;

    wstring map;

    map += L"################";
    map += L"#..............#";
    map += L"#..............#";
    map += L"#..............#";
    map += L"#..............#";
    map += L"#..............#";
    map += L"#..............#";
    map += L"#..............#";
    map += L"#..............#";
    map += L"#..............#";
    map += L"#..............#";
    map += L"#..............#";
    map += L"#..............#";
    map += L"#..............#";
    map += L"#..............#";
    map += L"################";

    bool bHitWallActually = false;
    if (fPlayerX < 2.0f || fPlayerX > 15.0f || fPlayerY < 2.0f || fPlayerY > 15.0f) {
        bHitWallActually = true;
    }


    while (1)
    {


        if (GetAsyncKeyState((unsigned short)'J') & 0x8000)
            fPlayerA -= (0.005f);
        if (GetAsyncKeyState((unsigned short)'K') & 0x8000)
            fPlayerA += (0.005f);
        if (GetAsyncKeyState((unsigned short)'W') & 0x8000) {
            fPlayerX += sinf(fPlayerA) * 0.005f;
            fPlayerY += cosf(fPlayerA) * 0.005f;

            if (bHitWallActually == true)
            {
                fPlayerX -= sinf(fPlayerA) * 0.005f;
                fPlayerY -= cosf(fPlayerA) * 0.005f;
            }

        }

        if (GetAsyncKeyState((unsigned short)'S') & 0x8000) {
            fPlayerX -= sinf(fPlayerA) * 0.005f;
            fPlayerY -= cosf(fPlayerA) * 0.005f;

        }
        if (GetAsyncKeyState((unsigned short)'A') & 0x8000) {
            fPlayerX -= cosf(fPlayerA) * 0.005f;
            fPlayerY += sinf(fPlayerA) * 0.005f;
        }
        if (GetAsyncKeyState((unsigned short)'D') & 0x8000) {
            fPlayerX += cosf(fPlayerA) * 0.005f;
            fPlayerY -= sinf(fPlayerA) * 0.005f;
        }


        for (int x = 0; x < nScreenWidth; x++)
        {
            float fRayAngle = (fPlayerA - fFOV / 2.0f) + ((float)x / (float)nScreenWidth) * fFOV;

            float fDistanceToWall = 0;
            bool bHitWall = false;
            float fEyeX = sinf(fRayAngle);
            float fEyeY = cosf(fRayAngle);

            while (!bHitWall && fDistanceToWall < fDepth)
            {
                fDistanceToWall += 0.1f;


                int nTestX = (int)(fPlayerX + fEyeX * fDistanceToWall);
                int nTestY = (int)(fPlayerY + fEyeY * fDistanceToWall);

                if (nTestX < 0 || nTestX >= nMapWidth || nTestY < 0 || nTestY >= nMapHeight)
                {
                    bHitWall = true;
                    fDistanceToWall = fDepth;
                }
                else
                {
                    if (map[nTestY * nMapWidth + nTestX] == '#')
                    {
                        bHitWall = true;
                    }
                }


            }


            int nCeiling = (float)(nScreenHeight / 2.0) - nScreenHeight / ((float)fDistanceToWall);
            int nFloor = nScreenHeight - nCeiling;

            for (int y = 0; y < nScreenHeight; y++)
            {
                if (y < nCeiling)
                    screen[y*nScreenWidth + x] = ' ';
                else if (y > nCeiling && y <= nFloor)
                    screen[y*nScreenWidth + x] = '#';
                else
                    screen[y*nScreenWidth + x] = '.';
            }
        }




        screen[nScreenWidth * nScreenHeight - 1] = '\0';
        WriteConsoleOutputCharacter(hConsole, screen, nScreenWidth * nScreenHeight, { 0,0 }, &dwBytesWritten);
    }

    system("pause");
    return 0;
}