/*
Game of life, 2d console mode
  Based on John Conway's coolness.
  Thx to inspirational Complexity and Stephen 
by eozl, July 27, 2003
tangledweb.ath.cx/files/source/c/gameoflife.c
                                               */

/*** INCLUDES ****/
#include <stdio.h> 
#include <unistd.h>
#include <stdlib.h>


/*** DEFINES ***/
#define SPANV 35
#define SPANH 60
#define ASC0 48  // ascii value for 0, for stoi()


/*** PROTOTYPES ***/
void  print    (short arr[SPANV][SPANH]);
void  seed     (short arr[SPANV][SPANH], int k);
int   surround (short arr[SPANV][SPANH], int x, int y);
int   stoi     (char *c);


/*** FUNCTIONS ***/
int main(int argc, char *argv[]) {

  short game [SPANV][SPANH];
  short gamed[SPANV][SPANH]; 
  int i,j,k,iter,maxiter;
  
  /* COMMAND LINE STF */
  static char cmdhelp[]=
"Program usage:
    [-?]        this help
    [-m VALUE]  maximum iterations (default 125)
    \n";

  short badflag=0, m=0 ,h=0;       // bools for args
  short printedhelp=0; // so we dont print help multiple times...
  if (argc>1) {                  // if there are any args
    for (i=1;i<argc;i++) {
      switch (argv[i][1]) {
      case 'm':
	maxiter=stoi(argv[++i]);
	m++;
	break;
      case '?':
    	if (!printedhelp) {
	  printf("%s",cmdhelp);
	  printedhelp=1;
	}
	h++;
	break;
      default:
    	if (!printedhelp) {
	  printf("%s",cmdhelp);
	  printedhelp=1;
	}
	printf("* Unknown argument: \"%s\"; going to bail\n",argv[i]);
 	badflag++;
	break;
      }
    }
  }
  
  if (!m) maxiter=125;
  if (h || badflag)
	return 1;
  
  
  /* Clear game-d[][] */
  for (i=0;i<SPANV;i++){
    for (j=0;j<SPANH;j++){
      game [i][j]=0;
      gamed[i][j]=0;
    }
  }


  seed(game,-1);
 

  /* Debug */
  //int dx,dy; dx=6; dy=4;
  //printf("Surrounding : %d\n\n",surround(game,dx,dy));
  //game[dx][dy]=-1;
  //print(game);
  //return 1;


  /* MAIN LOOP */
  for (iter=1;iter<=maxiter;iter++) {
    system("clear");              // i dont like this but it helps fps
    
    
    printf("\n\n==== %d of %d\n\n",iter,maxiter);
    print(game);
    for (i=0;i<SPANV;i++){
      for (j=0;j<SPANH;j++){      // for each point, update gamed[]
        k=surround(game,i,j);     // k is number of neighbors

        if (game[i][j]==0 && 3==k) { //dead + 3 k = birth
          gamed[i][j]=1;
        }
        else if ((2==k || 3==k) && 1==game[i][j]){ 
          gamed[i][j]=1;             //alive+2|3=survival
        }
        else{                        //die die die
          //gamed[i][j]=0;           // not needed, gamed starts as 0
        }
        
      }
    }
    for (i=0;i<SPANV;i++){        // copy gamed[] to game[]
      for (j=0;j<SPANH;j++){
        game[i][j]=gamed[i][j];
        gamed[i][j]=0;
      }
    }
    usleep(90000);                // make em go 'oo aa'
  }
  return 0;  
}


// all-purpose string to int.
int stoi(char *c) {
  int i;
  int n=(int)c[0]-ASC0;           // ascii '0' is 48. 
  
  for (i=1; c[i]!='\0'; i++) {
    n*=10;
    n+=(int)c[i]-ASC0;
  }
  return n;
}

// returns number of neighbors
int surround(short arr[SPANV][SPANH], int x, int y) { //x,y: down,right
  int top=0,bottom=0,left=0,right=0;     //bools essentially

  if (x<=0)
    top=1;
  if (x>= (SPANV - 1))
    bottom=1;
  
  if (y<=0) 
    left=1;
  if (y>= (SPANH - 1))
    right=1;

  //printf("top %d, bottom %d, left %d, right %d\n\n",top,bottom,left,right);
  //return -1;
  
  int n=0;

  //comments n,s,w,e=north/south/west/east etc.

  //nw. check here only if its not top and not left
  if (!top && !left) {
    if (arr[x-1][y-1])
      {n++;}
  }
  if (!top) {
    if (arr[x-1][y])   //n
      {n++;}
  }
  if (!top && !right) {
    if (arr[x-1][y+1])  //ne
      {n++;}
  }
  
  
  if (!left) {
    if (arr[x][y-1])    //w
      {n++;}
  }
  if (!right) {
    if (arr[x][y+1])    //e
      {n++;}
  }
  
  
  if(!bottom && !left){
    if (arr[x+1][y-1])
      {n++;}
  }
  if (!bottom) {
    if (arr[x+1][y])
      {n++;}
  }
  if (!bottom && !right) {
    if (arr[x+1][y+1])
      {n++;}
  }

  return n;
}


// seed the virgin board with start spark
void seed(short arr[SPANV][SPANH], int k) {
  int i;
  switch (k) {
  case 1: // 3 vertical dots
    arr[SPANV/2][SPANH/2]=1;
    arr[SPANV/2+1][SPANH/2]=1;
    arr[SPANV/2-1][SPANH/2]=1;
    break;
    
  case 2: //test deal
    arr[SPANV/2][SPANH/2]=1;
    arr[SPANV/2][SPANH/2+1]=1;
    arr[SPANV/2+1][SPANH/2]=1;
    arr[SPANV/2+1][SPANH/2+1]=1;
    arr[SPANV/2+1][SPANH/2+2]=1;
    break;
    
  case 3: //"r-pentomino"
    arr[SPANV/2][SPANH/2]=1;
    arr[SPANV/2+1][SPANH/2]=1;
    arr[SPANV/2-1][SPANH/2]=1;
    arr[SPANV/2][SPANH/2-1]=1;
    arr[SPANV/2-1][SPANH/2+1]=1;
    break;
    
  case 4: //horiz line of __ length 
    for (i=SPANH/2-12;i<SPANH/2+13;i++)
      arr[SPANV/2][i]=1;
    break;

  case 5: //vert line, as tall as possible
  default:
    for (i=1;i<SPANV-1;i++)
      arr[i][SPANH/2]=1;    
    break;
  }
}

// print out any 2d array of nul/!nul
void print(short arr[SPANV][SPANH]) {
  int i, j;
  for (i=0; i<SPANV; i++) {
    for (j=0; j<SPANH; j++) {
      arr[i][j] ? printf("# ") : printf("  ");

      //printf("%d ",arr[i][j]);
      /* //For special characters
      switch (arr[i][j]) {
        case -1: printf("! "); break;
        case  0: printf("  "); break;
        case  1: default: printf("# "); break;
      }
      */
    }
    printf("\n");
  }
}


// DAMN new order's someone like you is HOT