Where can I walk step by step? - on JS - by Jack

clue_test.html

<script>
	/*
		Where can I walk step by step? - by Jack
	
		0 = can walk
		1 = a wall
		
		Other numbers > padding = steps
	*/
	var map = [
		[0,0,0,0,0,0,0,0,0,0],
		[0,0,0,0,0,0,0,0,0,0],
		[0,0,0,0,0,0,0,0,0,0],
		[0,0,0,0,0,1,0,0,0,0],
		[0,0,0,0,0,0,1,0,0,0],
		[0,0,0,0,0,0,1,0,0,0],
		[0,0,0,0,0,0,0,0,0,0],
		[0,0,0,0,0,0,0,0,0,0],
		[0,0,0,0,0,0,0,0,0,0],
		[0,0,0,0,0,0,0,0,0,0],
	];
	
	var point = [4,4];
	var distance = 2; //try with 6!
	
	show_map();
	build_layer( 1, point, distance );
	
	/* This is magic from jack */
	function build_layer( step, point, distance ){
		var padding = 2; //padding dont include reserved status like 1 = block
		var new_step = step + padding; //the real code of the steps
		if( step == 1){ //first time dont exist nothing, so go to origin
			map[point[0]][point[1]] = new_step;
		}else{
			var width = map[0].length;
			var height = map.length;
			for(var y=0; y < height; y++){
				for(var x=0; x < width;x++){
					if( map[x][y] == new_step - 1 ){
						x_p = x+1; x_l = x-1; y_p = y+1; y_l = y-1;
						if(	x_p < width //less than width
							&& map[x_p][y]!=1  //dont a block: can be a method to get all blocks not only '1'
							&& !(map[x_p][y]>padding && map[x_p][y]<=padding+distance) //dont a current step
						){ map[x_p][y] = new_step; }
						if(	x_l >= 0 && map[x_l][y]!=1 && !(map[x_l][y]>padding && map[x_l][y]<=padding+distance)){ map[x_l][y] = new_step; }
						if(y_p < height && map[x][y_p]!=1 && !(map[x][y_p]>padding && map[x][y_p]<=padding+distance)){ map[x][y_p] = new_step; }
						if(y_l >= 0 && map[x][y_l]!=1 && !(map[x][y_l]>padding && map[x][y_l]<=padding+distance)){ map[x][y_l] = new_step; }
					}
				}
			}
		}
		show_map(); //for debug
		if( step+1 <= distance ){ //limit of steps
			build_layer( step+1, point, distance );
		}
	}
	
	function show_map(){
		for(var i=0; i < map.length; i++){
			print_line = "";
			for(var j=0; j < map[0].length; j++){
				print_line += map[i][j]+"";
			}
			console.log( print_line  );
		}
		console.log("----------------------");
	}
</script>