#include <iostream>
#include <sys/ioctl.h>
#include <stdio.h>
#include <unistd.h>
#include <chrono>
#include <thread>
#include <cmath>
#include <stdlib.h>
#include <ncurses.h>
#include <pthread.h>
#include <termios.h>

using namespace std;
using namespace std::chrono;


//#include <vector>
char cInput[5];
string debugMsg;

bool bGameLoop = true;
int nScreenWidth;
int nScreenHeight;
string screen;


  int pressedKeys[10];

int khbit()
{
    struct timeval tv;
    fd_set fds;
    tv.tv_sec = 0;
    tv.tv_usec = 0;
    FD_ZERO(&fds);
    FD_SET(STDIN_FILENO, &fds);
    select(STDIN_FILENO+1, &fds, NULL, NULL, &tv);
    return FD_ISSET(STDIN_FILENO, &fds);
}
void nonblock(int state)
{
    struct termios ttystate;
    tcgetattr(STDIN_FILENO, &ttystate);

    if ( state == 1)
    {
        ttystate.c_lflag &= (~ICANON & ~ECHO); //Not display character
        ttystate.c_cc[VMIN] = 1;
    }
    else if (state == 0)
    {
        ttystate.c_lflag |= ICANON;
    }
    tcsetattr(STDIN_FILENO, TCSANOW, &ttystate);
}
bool keyState(int key) //Use ASCII table
{
    bool pressed;
    int i = khbit(); //Alow to read from terminal
    if (i != 0)
    {
        char c = fgetc(stdin);
        if (c == (char) key) pressed = true;
        else pressed = false;
    } else {
      //pressed = 0;
    }
    return pressed;
}

void *keyListener(void *tid){
  long id = (long) tid;

  //initscr();
  /*noecho();
  raw();
  cbreak();

  nodelay(stdscr, TRUE);
  scrollok(stdscr, TRUE);
  */
  //raw();

  while(bGameLoop){
    nonblock(1);
    if(keyState(32)) debugMsg = "yo";
    debugMsg = to_string(keyState(32));
    if(keyState(32)) debugMsg = "yo";
    nonblock(0);
    //int c;
    //while ((c = getch()) != ERR)
    //    debugMsg+=to_string(c);

    /*if(getch() == 'a'){
      debugMsg = "wawawa";
    } else {
      debugMsg = "";
    }*/
    //cInput[0] = getch();
    /*switch(getch()){
      case 'a':
        debugMsg = "wawawa";
      break;
      case 'ERR':
        debugMsg = "error";
        break;
      default:
        debugMsg = " ";
      break;
    } */
  }
  //endwin();
  pthread_exit(NULL);
}




void writeStringToScreen(int x, int y, string text){
  int s = (y*nScreenWidth)+x;
  for (int i = s; i < s+text.length(); i++){
    screen[i] = text[i-s];
  }
}

int main(){
  //cInput = {'a','b'};

  //fputs("\e[?25h", stdout); //get cursor back /on signal abort ~
  //setterm(1);
  pthread_t pThread[1];
  pthread_create(&pThread[0], NULL, keyListener, 0);


  struct winsize size;
  ioctl(STDOUT_FILENO,TIOCGWINSZ,&size);

  nScreenWidth = size.ws_col;
  nScreenHeight = size.ws_row;



  int nFrameRate = 60;

  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;

  string map;
  map += "################";
  map += "#..............#";
  map += "#..............#";
  map += "#..............#";
  map += "#..............#";
  map += "#..............#";
  map += "#..............#";
  map += "#..............#";
  map += "#..............#";
  map += "#..............#";
  map += "#..............#";
  map += "#..............#";
  map += "#..............#";
  map += "#..............#";
  map += "#..............#";
  map += "################";


  using clock = steady_clock;
  auto tp1 = clock::now();
  auto tp2 = clock::now();


  fputs("\e[?25l", stdout); //remove cursor*/

  while(bGameLoop){

    tp2 = clock::now();
    duration<float> elapsedTime = tp2 - tp1;
    tp1 = tp2;
    float fElapsedTime = elapsedTime.count();


     //dynamic terminal window size (on Window Resize)
    ioctl(STDOUT_FILENO,TIOCGWINSZ,&size);
    nScreenWidth = size.ws_col;
    nScreenHeight = size.ws_row;


    screen.clear();
    screen.resize(nScreenWidth*nScreenHeight);


    cout << "\x1B[0;0H"; //reset cursor to 0,0


    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] = ' ';
        if(y > nCeiling && y <= nFloor)
          screen[y*nScreenWidth+x] = '#';
        else
          screen[y*nScreenWidth+x] = ' ';
      }
    }

    //writeStringToScreen(0, 0, "Key pressed: " + to_string(123) + " Key code: " + to_string(cInput));
    //writeStringToScreen(0, nScreenHeight-3, debugMsg);
    writeStringToScreen(0, nScreenHeight-2, "Frame rate: " + to_string(1.0f / fElapsedTime) + " limited to " + to_string(nFrameRate));
    //string sInput(1, cInput[0]);
    writeStringToScreen(0, nScreenHeight-1, debugMsg);


    cout << screen; //this is the renderer
    //cout << ;

    tp1 += milliseconds(1000 / nFrameRate);
    this_thread::sleep_until(tp1);

  }

  return 0;
}