draggable.js

//Function to enable reposition cover
function enableRepositionCover() {
    $("#cover_image").css('cursor','move');
    var y1 = $('.img-header').height();
    var y2 = $('#cover_image').height();
      $("#cover_image").liveDraggable({
          scroll: false,
          axis: "y",
          drag: function(event, ui) {
              if(ui.position.top >= 0)
              {
                  ui.position.top = 0;
              }
              else if(ui.position.top <= y1 - y2)
              {
                  ui.position.top = y1 - y2;
              }
        },
          stop: function(event, ui) {
           var img = {
                  "id": $(this).attr('id'),
                  "position_y": $(this).position().top.toString(),
                  "position_x": $(this).position().left.toString()
          };

          $("#farm_cover_position_x").val(img.position_x);
          $("#farm_cover_position_y").val(img.position_y);
        }
    });
}

//Function to disable reposition cover
function disableRepositionCover(){
  $('#drag_instruction').css('visibility','hidden');
  $("#cover_image").draggable('destroy');
  $('.cover-editor-bar').css('visibility','hidden');
  $("#cover_image").css('cursor','default');
}