#include "fxlib.h"
#include "MonochromeLib.h"
#include "syscall.h"
#include <math.h>
#include <stdio.h>

static int SysCallCode[] = {0xD201422B,0x60F20000,0x80010070};
static int (*SysCall)(int R4, int R5, int R6, int R7, int FNo ) = (void*)&SysCallCode;

int RTC_GetTicks(void)
{
     return (*SysCall)(0, 0, 0, 0, 0x3B);
}

long abs(long value)
{
  if (value < 0) return -value;
  else return value;
}

#define mapWidth 64
#define mapHeight 64

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},
  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,0,0,0,0,0,2,2,2,2,2,0,0,0,0,3,0,3,0,3,0,0,0,1},
  {1,0,0,0,0,0,2,0,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,0,0,0,0,0,2,0,0,0,2,0,0,0,0,3,0,0,0,3,0,0,0,1},
  {1,0,0,0,0,0,2,0,0,0,2,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,0,0,0,0,0,2,2,0,2,2,0,0,0,0,3,0,3,0,3,0,0,0,1},
  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,4,4,4,4,4,4,4,4,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,4,0,4,0,0,0,0,4,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,4,0,0,0,0,5,0,4,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,4,0,4,0,0,0,0,4,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,4,0,4,4,4,4,4,4,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,4,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,4,4,4,4,4,4,4,4,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1},
  {1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1}
};

int AddIn_main(int isAppli, unsigned short OptionNum)
{
  int rotSpeed, moveSpeed; // Vitesse de rotation et de mouvement
  int w = 128, h = 64, x; // Dimensions de l'écran
  double posX = 22, posY = 12; // Position du joueur
  double dirX = -1, dirY = 0;
  double planeX = 0, planeY = 0.66;

  double time = 0, oldTime = 0;
  char fps[3];

  double cameraX;
  double rayPosX, rayPosY;
  double rayDirX, rayDirY;

  int mapX, mapY;

  double sideDistX, sideDistY;
  double deltaDistX, deltaDistY;
  double perpWallDist;

  int stepX, stepY;
  int hit, side;
  int lineHeight;

  int drawStart;

  int drawEnd;
  double frameTime;

  double oldDirX;
  double oldPlaneX;

  while(IsKeyUp(KEY_CTRL_EXIT))
  {
    ML_clear_vram();

    for(x = 0; x < w; x++)
    {
       cameraX = 2 * x / (double)(w) - 1;
       rayPosX = posX, rayPosY = posY;
       rayDirX = dirX + planeX * cameraX, rayDirY = dirY + planeY * cameraX;

       mapX = (int)(rayPosX), mapY = (int)(rayPosY);

       sideDistX, sideDistY;
       deltaDistX = sqrt(1 + (rayDirY * rayDirY) / (rayDirX * rayDirX)), deltaDistY = sqrt(1 + (rayDirX * rayDirX) / (rayDirY * rayDirY));
       perpWallDist;

       stepX, stepY;
       hit = 0, side;

      if (rayDirX < 0)
      {
        stepX = -1;
        sideDistX = (rayPosX - mapX) * deltaDistX;
      }
      else
      {
        stepX = 1;
        sideDistX = (mapX + 1.0 - rayPosX) * deltaDistX;
      }
      if (rayDirY < 0)
      {
        stepY = -1;
        sideDistY = (rayPosY - mapY) * deltaDistY;
      }
      else
      {
        stepY = 1;
        sideDistY = (mapY + 1.0 - rayPosY) * deltaDistY;
      }

      while (hit == 0) // DDA
      {
        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 = fabs((mapX - rayPosX + (1 - stepX) / 2) / rayDirX);
      else
        perpWallDist = fabs((mapY - rayPosY + (1 - stepY) / 2) / rayDirY);

       lineHeight = abs((int)(h / perpWallDist));

       drawStart = -lineHeight / 2 + h / 2;
      if(drawStart < 0)drawStart = 0;
       drawEnd = lineHeight / 2 + h / 2;
      if(drawEnd >= h)drawEnd = h - 1;

      ML_vertical_line(x, drawStart, drawEnd, ML_BLACK);
    }

    //Gestion du temps et de la vitesse
    oldTime = time;
    time = RTC_GetTicks();
    frameTime = (time - oldTime) / 1000.0;
    sprintf(fps,"%d",frameTime / 1000.0);
    PrintXY(0,0,(const unsigned char *) fps,0);

     moveSpeed = frameTime * 30.0;
     rotSpeed = frameTime * 15.0;

    //Gestion des touches
    if (IsKeyDown(KEY_CTRL_UP))
    {
      if(worldMap[(int)(posX + dirX * moveSpeed)][(int)(posY)] == 0) posX += dirX * moveSpeed;
      if(worldMap[(int)(posX)][(int)(posY + dirY * moveSpeed)] == 0) posY += dirY * moveSpeed;
    }

    if (IsKeyDown(KEY_CTRL_DOWN))
    {
      if(worldMap[(int)(posX - dirX * moveSpeed)][(int)(posY)] == 0) posX -= dirX * moveSpeed;
      if(worldMap[(int)(posX)][(int)(posY - dirY * moveSpeed)] == 0) posY -= dirY * moveSpeed;
    }

    if (IsKeyDown(KEY_CTRL_RIGHT))
    {
       oldDirX = dirX;
      dirX = dirX * cos(-rotSpeed) - dirY * sin(-rotSpeed);
      dirY = oldDirX * sin(-rotSpeed) + dirY * cos(-rotSpeed);
       oldPlaneX = planeX;
      planeX = planeX * cos(-rotSpeed) - planeY * sin(-rotSpeed);
      planeY = oldPlaneX * sin(-rotSpeed) + planeY * cos(-rotSpeed);
    }

    if (IsKeyDown(KEY_CTRL_LEFT))
    {
       oldDirX = dirX;
      dirX = dirX * cos(rotSpeed) - dirY * sin(rotSpeed);
      dirY = oldDirX * sin(rotSpeed) + dirY * cos(rotSpeed);
       oldPlaneX = planeX;
      planeX = planeX * cos(rotSpeed) - planeY * sin(rotSpeed);
      planeY = oldPlaneX * sin(rotSpeed) + planeY * cos(rotSpeed);
    }

    ML_display_vram();
  }
    return 1;
}

#pragma section _BR_Size
unsigned long BR_Size;
#pragma section
#pragma section _TOP
int InitializeSystem(int isAppli, unsigned short OptionNum)
{
    return INIT_ADDIN_APPLICATION(isAppli, OptionNum);
}
#pragma section