$this.checkMove = function (tileNum){
    var direction = null;
    var tile;
    for(var i=0; i<16; i++){
        if(tiles.allTiles[i] == tileNum){
            if(tiles.allTiles[i-1] === 0 && i !== 0 && i != 4 && i != 8 && i != 12){
                direction = "left";
                tile= tiles.findName("tile"+tileNum);
                moveTile(tile,direction);
                tiles.allTiles[i-1]=tileNum;
                tiles.allTiles[i]=0;
                break;
            }
            if(tiles.allTiles[i-4] === 0){
                direction = "up";
                tile = tiles.findName("tile"+tileNum);
                moveTile(tile,direction);
                tiles.allTiles[i-4]=tileNum;
                tiles.allTiles[i]=0;
                break;
            }

            direction = "down";
            tile = tiles.findName("tile"+tileNum);
            moveTile(tile,direction);
            tiles.allTiles[i+4]=tileNum;
            tiles.allTiles[i]=0;
            break;

        }

        if(tiles.allTiles[i+1] === 0 && i != 3 && i != 11 && i != 15){
            direction = "right";
            tile = tiles.findName("tile"+tileNum);
            moveTile(tile,direction);
            tiles.allTiles[i+1]=tileNum;
            tiles.allTiles[i]=0;
            break;
        }

    }
}


function moveTile(tile, direction){
    if(direction == "up"){
        tile.y(tile.y()-tiles.tileDist);

    } else if(direction == "down"){
        tile.y(tile.y()+tiles.tileDist);

    } else if(direction == "left"){
        tile.x(tile.x()-tiles.tileDist);

    } else if(direction == "right"){
        tile.x(tile.x()+tiles.tileDist);
    }
}