//---- normal P5 code -------------------------------------------------------


function makeGrid(cols, rows){
  let arr = new Array(cols);
  for (let i = 0; i < arr.length; i++){
    arr[i] = new Array(rows);
  }
  return arr;
}

let grid;
let cols;
let rows;
let resolution = 20;

function setup() {
  createCanvas(1000,600);
  cols = width / resolution;
  rows = height / resolution
  grid = makeGrid(cols,rows);
  for(let i = 0; i < cols; i++){
    for(let j = 0; j < rows; j++){
      grid[i][j] = floor(random(2));
    }
  }
}

function draw() {
  background(0);

  for(let i = 0; i < cols; i++){
    for(let j = 0; j < rows; j++){
      let x = i * resolution;
      let y = j * resolution;
      if (grid[i][j] == 1){
        fill(255);
        rect(x,y,resolution - 1,resolution - 1);
      }
    }
  }

  let next = makeGrid(cols,rows);

  for(let i = 0; i < cols; i++){
    for(let j = 0; j < rows; j++){

      let state = grid[i][j];
      console.log(state);

        let sum = 0;
        let neighbours = count(grid, i, j);

        if (state === 0 && neighbours == 3){
          next[i][j] = 1;
        } else if (state == 1 && (neighbours < 2 || neighbours > 3)){
          next[i][j] = 0;
        } else {
          next[i][j] = state;
        }

    }
  }
  grid = next;
}

function count(grid, x, y){
  let sum = 0;
  for (let i = -1; i < 2; i++){
    for (let j = -1; j < 2; j++){

      let col = (x + i + cols) % cols;
      let row = (y + j + rows) % rows;

      sum += grid[col][row];
    }
  }
  sum -= grid[x][y];
  return sum;
}