var scl = 40;

var grid = [];

var stack = [];

var ends = [];

var current;

var gate1 = 0;

​

function setup() {

  createCanvas(400, 400);

  cols = floor(width/scl);

  rows = floor(height/scl);

  for(var j = 0; j < rows; j++){

    for(var i = 0; i< cols; i++){

      var cell = new Cell(i,j);

      grid.push(cell)

    }

  }

  current = grid[0];

  //frameRate(2);

}

​

function draw() {

  background(51);

  if(gate1 == 0){

    for(let i = 0; i < 1; i ++){

      backtracking();

    }

  }else if(gate1 == 1){

      for(let end of ends){

        end.highlight();

        let choice = random(1);

        if(choice < 0.5){

          let wall = random(end.walls);

          console.log("1",end.walls)

          while(!wall){

            wall = random(end.walls);

          }

          end.wall = false;

          console.log("2",end.walls)

        }

    }

  gate1++;

  }else{

    for(let i = 0; i < grid.length; i++){

      grid[i].show();

    }

  }

}

​

var gate = true;

​

function backtracking(){

  for(var i = 0; i < grid.length; i++){

    grid[i].show();

  }

  current.visited = true;

  current.highlight();

  //Step 1

  var next = current.checkNeigbors();

  if (next) {

    next.visited = true;

    //Step 2

    stack.push(current);

    //Step 3

    removeWalls(current,next);

    //Step 4

    current = next;

    gate = true;

  } else if(stack.length > 0){ 

    if(gate){

      ends.push(current);

      gate = false;

    }

    current = stack.pop();

  }

  if(current == grid[0]){

    gate1 ++;

  }

}

​

function index(i,j){

  if(i < 0 || j < 0 || i > cols-1|| j > rows-1){

    return -1;

  }

  return i + j * cols;

}

​

function removeWalls(a,b) {

  var x = a.i - b.i;

  if(x === 1){

    a.walls[3] = false;

    b.walls[1] = false;

  } else if (x === -1){

    a.walls[1] = false;

    b.walls[3] = false;

  }

  var y = a.j - b.j;

  if(y === 1){

    a.walls[0] = false;

    b.walls[2] = false;

  } else if (y === -1){

    a.walls[2] = false;

    b.walls[0] = false;

  }

}