var pos_supported = false;

var pos_in_drag = false;

var posslide_init = function()

{

  // make sure the theme supports the playhead

  var base = document.getElementById('playhead');

  var inner = document.getElementById('playhead-filler');

  var slider = document.getElementById('playhead-button');

  if ( !slider || !inner || !base )

    return false;

  pos_supported = true;

  var minX = $(base).Left() - 3;

  var minY = $(base).Top() + 3;

  var maxY = minY;

  var maxX = minX + $(base).Width() - 6;

  Drag.init(slider, slider, minX, maxX, minY, maxY);

  slider.onDrag = posslide_handle_drag;

  slider.onDragEnd = posslide_handle_dragend;

  slider.onDragStart = function(x, y) { pos_in_drag = true; };

  base.onclick = posslide_handle_click;

  posslide_set_position(0);

  slider.style.top = minY + 'px';

}

var posslide_handle_drag = function(x, y, do_inner)

{

  var inner = document.getElementById('playhead-filler');

  var slider = document.getElementById('playhead-button');

  var size = x - $(inner).Left() + 8;

  if ( do_inner )

    inner.style.width = size + 'px';

  if ( ( pos_in_drag && !do_inner ) || ( !pos_in_drag && do_inner ) )

    slider.style.left = ( x ) + 'px';

}

var posslide_handle_dragend = function(x, y)

{

  pos_in_drag = false;

  var inner = document.getElementById('playhead-filler');

  var base = document.getElementById('playhead');

  var multiplier = $(base).Width();

  var pos = x - $(inner).Left() + 8;

  pos = 100 * ( pos / multiplier );

  set_playback_position(pos);

}

var posslide_handle_click = function(e)

{

  e = Drag.fixE(e);

  var base = document.getElementById('playhead');

  var val = e.clientX - $(base).Left();

  val = 100 * ( val / $(base).Width() );

  posslide_set_position(val);

  set_playback_position(val);

}

function posslide_set_position(pos)

{

  if ( !pos_supported )

    return false;

  // pos needs to be 1-100

  var base = document.getElementById('playhead');

  var multiplier = $(base).Width();

  pos = ( pos / 100 ) * multiplier;

  var left = pos + $(base).Left();

  posslide_handle_drag(left, 0, true);

}

addOnloadHook(posslide_init);