/*******************\
|  Pong             |
|                   |
|  By Alnotz        |
\*******************/
/*
gcc -o pong pong.c `/usr/bin/pkg-config --libs --cflags ncurses`
*/
#include <stdlib.h>
#include <time.h>
/*Ncurses header*/
#include <curses.h>
/*Inner window size*/
#define LINE 40
#define COL  80
/*Inner window title & border*/
#define DO_TITLE(void) \
  /*Inner border*/\
  box(inwin, '|', '-');\
  /*Inner window title*/\
  wmove(inwin, 0, COL/4);\
  wattron(inwin, COLOR_PAIR(2));\
  wprintw(inwin, "Push 'q' to quit");\
  wmove(inwin, 0, COL-11);\
  timespec_get(&ts, TIME_UTC);\
  strftime(buff, sizeof buff, "%H:%M\'%S\"", gmtime(&ts.tv_sec));\
  wprintw(inwin, "%s", buff);\
  wattroff(inwin, COLOR_PAIR(2));
/*False asynchronization timer*/
unsigned int tmr=0;
/*Inner window*/
WINDOW *inwin;
/*Cursor position*/
int bracket_Rl=LINE-1, bracket_Rc=COL/2, startl, startc;
/*Ball position*/
int ball_Rl=LINE-2, ball_Rc=COL/2, ball_Vl=-1, ball_Vc=1;
/*Key number*/
int ch;
/*Bloc array*/
char blocs0[COL];
/*Clock*/
struct timespec ts;
char buff[20];
void blocs_ltest(char *blc[], const int *ball_Rl, 
                 const int *ball_Rc, int *ball_Vl)
{
  const size_t lsize = (sizeof *blc) / (sizeof *blc[0]);
  if(*ball_Rl==1 || *ball_Rl==3 && *blc[*ball_Rc]=='#')
  {
    *blc[*ball_Rc]==' ';
    *ball_Vl = -*ball_Vl;
  }
}

int ball_Vl_test(void)
{
  const int lwall = ball_Rl<1 || ball_Rl>LINE-2;
  const int br_csize = ball_Rc>=bracket_Rc && ball_Rc<bracket_Rc+2;
  const int br_bot = ball_Rl==bracket_Rl-1 && ball_Vl>0;
  const int br_up = ball_Rl==bracket_Rl+1 && ball_Vl<0;
  return lwall || (br_csize && br_bot) || (br_csize && br_up);
}
int ball_Vc_test(void)
{
  const int cwall = ball_Rc<1 || ball_Rc>COL-2;
  const int br_lsize = ball_Rl==bracket_Rl;
  const int br_left = ball_Rc==bracket_Rc-1 && ball_Vc>0;
  const int br_right = ball_Rc==bracket_Rc+3 && ball_Vc<0;
  return cwall || (br_lsize && br_left) || (br_lsize && br_right);
}
int main(int argc, char *argv[])
{
  /*Outer window*/
  initscr();
  startl=LINES/2-LINE/2;
  startc=COLS/2-COL/2;
  /*Color enabled*/
  start_color();
  init_pair(1, COLOR_RED, COLOR_BLACK);
  init_pair(2, COLOR_GREEN, COLOR_BLACK);
  init_pair(3, COLOR_BLUE, COLOR_BLACK);
  init_pair(4, COLOR_YELLOW, COLOR_BLACK);
  /*Cursor hidden*/
  curs_set(0);
  /*Inner window set*/
  inwin = newwin(LINE, COL, startl, startc);
  /*Timeout enabled for wgetch*/
  wtimeout(inwin, 20);
  /*Keypad enabled*/
  keypad(inwin, TRUE);
  DO_TITLE()
  /*Initial blocs*/
  for(int i=0; i<LINE-1; i++)
  {
    if((i>3 && i<10) || (i>23 && i<30))
    {
      blocs0[i]='#';
    }
    else
    {
      blocs0[i]=' ';
    }
  }
  /*First blocs position*/
  wmove(inwin, 2, 1);
  /*Blocs in yellow*/
  wattron(inwin, COLOR_PAIR(4));
  wprintw(inwin, "%s", blocs0);
  wattroff(inwin, COLOR_PAIR(4));
  /*First cursor position*/
  wmove(inwin, bracket_Rl, bracket_Rc);
  /*Cursor in red*/
  wattron(inwin, COLOR_PAIR(1));
  wprintw(inwin, "###");
  wattroff(inwin, COLOR_PAIR(1));
  /*Ball in blue*/
  wmove(inwin, ball_Rl, ball_Rc);
  wattron(inwin, COLOR_PAIR(3));
  wprintw(inwin, "O");
  wattroff(inwin, COLOR_PAIR(3));
  /*Inner window updated*/
  wrefresh(inwin);
  /*Key expected*/
  ch = wgetch(inwin);
  /*Inner window cleared before next update*/
  wclear(inwin);
  while(ch!=(int)'q')
  {
    DO_TITLE()
     /*First blocs position*/
    wmove(inwin, 2, 1);
    /*Blocs in yellow*/
    wattron(inwin, COLOR_PAIR(4));
    wprintw(inwin, "%s", blocs0);
    wattroff(inwin, COLOR_PAIR(4));
    /*Cursor movement*/
    switch(ch)
    {
      case KEY_RIGHT:
        if(bracket_Rc==COL-3)
          wmove(inwin, bracket_Rl, bracket_Rc);
        else
          wmove(inwin, bracket_Rl, ++bracket_Rc);
        break;
      case KEY_LEFT:
        if(bracket_Rc==0)
          wmove(inwin, bracket_Rl, bracket_Rc);
        else
          wmove(inwin, bracket_Rl, --bracket_Rc);
        break;
      case KEY_DOWN:
        if(bracket_Rl==LINE-1)
          wmove(inwin, bracket_Rl, bracket_Rc);
        else
          wmove(inwin, ++bracket_Rl, bracket_Rc);
        break;
      case KEY_UP:
        if(bracket_Rl==0)
          wmove(inwin, bracket_Rl, bracket_Rc);
        else
          wmove(inwin, --bracket_Rl, bracket_Rc);
        break;
      /*No key pushed*/
      case ERR:
        wmove(inwin, bracket_Rl, bracket_Rc);
        break;
    }
    wattron(inwin, COLOR_PAIR(1));
    wprintw(inwin, "###");
    wattroff(inwin, COLOR_PAIR(1));
    /*Ball movement*/
    if(tmr==4)
    {
      if(ball_Vl_test())
      {
        ball_Vl=-ball_Vl;
      }
      if(ball_Vc_test())
      {
        ball_Vc=-ball_Vc;
      }
      ball_Rl=ball_Rl+ball_Vl;
      ball_Rc=ball_Rc+ball_Vc;
      tmr=0;
    }
    else
    {
      tmr+=1;
    }
    wmove(inwin, ball_Rl, ball_Rc);
    wattron(inwin, COLOR_PAIR(3));
    wprintw(inwin, "O");
    wattroff(inwin, COLOR_PAIR(3));
    wrefresh(inwin);
    ch = wgetch(inwin);
    wclear(inwin);
  }
  endwin();
  return EXIT_SUCCESS;
}