var drag =
{
  obj : null,

  init : function(o, oRoot, minX, maxX, minY, maxY, bSwapHorzRef, bSwapVertRef, fXMapper, fYMapper)
  {
    o.onmousedown = drag.start;
    o.hmode       = bSwapHorzRef         ? false : true;
    o.vmode       = bSwapVertRef         ? false : true;
    o.root        = oRoot && oRoot!=null ? oRoot : o;

    if (o.hmode  && isNaN(parseInt(o.root.style.left  ))) o.root.style.left   = "0px";
    if (o.vmode  && isNaN(parseInt(o.root.style.top   ))) o.root.style.top    = "0px";
    if (!o.hmode && isNaN(parseInt(o.root.style.right ))) o.root.style.right  = "0px";
    if (!o.vmode && isNaN(parseInt(o.root.style.bottom))) o.root.style.bottom = "0px";

    o.minX    = typeof minX != 'undefined' ? minX : null;
    o.minY    = typeof minY != 'undefined' ? minY : null;
    o.maxX    = typeof maxX != 'undefined' ? maxX : null;
    o.maxY    = typeof maxY != 'undefined' ? maxY : null;
    o.xMapper = fXMapper ? fXMapper : null;
    o.yMapper = fYMapper ? fYMapper : null;

    o.root.onDragStart = new Function();
    o.root.onDragEnd   = new Function();
    o.root.onDrag      = new Function();
  },

  start : function(e)
  {
    var o = drag.obj = this;
    e     = drag.fixevent(e);
    var y = parseInt(o.vmode ? o.root.style.top  : o.root.style.bottom);
    var x = parseInt(o.hmode ? o.root.style.left : o.root.style.right);
    o.root.onDragStart(x,y);

    o.lastMouseX = e.clientX;
    o.lastMouseY = e.clientY;

    if (o.hmode)
    {
      if (o.minX != null) o.minMouseX = e.clientX   - x      + o.minX;
      if (o.maxX != null) o.maxMouseX = o.minMouseX + o.maxX - o.minX;
    }
    else
    {
      if (o.minX != null) o.maxMouseX = -o.minX + e.clientX + x;
      if (o.maxX != null) o.minMouseX = -o.maxX + e.clientX + x;
    }

    if (o.vmode)
    {
      if (o.minY != null) o.minMouseY = e.clientY   - y      + o.minY;
      if (o.maxY != null) o.maxMouseY = o.minMouseY + o.maxY - o.minY;
    }
    else 
    {
      if (o.minY != null) o.maxMouseY = -o.minY + e.clientY + y;
      if (o.maxY != null) o.minMouseY = -o.maxY + e.clientY + y;
    }

    document.onmousemove = drag.drag;
    document.onmouseup   = drag.end;
    return false;
  },

  drag : function(e)
  {
    e      = drag.fixevent(e);
    var o  = drag.obj;
    var ey = e.clientY;
    var ex = e.clientX;
    var y  = parseInt(o.vmode ? o.root.style.top  : o.root.style.bottom);
    var x  = parseInt(o.hmode ? o.root.style.left : o.root.style.right);
    var nx, ny;

    if (o.minX != null) ex = o.hmode ? Math.max(ex, o.minMouseX) : Math.min(ex, o.maxMouseX);
    if (o.maxX != null) ex = o.hmode ? Math.min(ex, o.maxMouseX) : Math.max(ex, o.minMouseX);
    if (o.minY != null) ey = o.vmode ? Math.max(ey, o.minMouseY) : Math.min(ey, o.maxMouseY);
    if (o.maxY != null) ey = o.vmode ? Math.min(ey, o.maxMouseY) : Math.max(ey, o.minMouseY);

    nx = x + ((ex - o.lastMouseX) * (o.hmode ? 1 : -1));
    ny = y + ((ey - o.lastMouseY) * (o.vmode ? 1 : -1));

    if (o.xMapper) nx = o.xMapper(y); else
    if (o.yMapper) ny = o.yMapper(x);

    drag.obj.root.style[o.hmode ? "left" : "right"] = nx + "px";
    drag.obj.root.style[o.vmode ? "top" : "bottom"] = ny + "px";
    drag.obj.lastMouseX	= ex;
    drag.obj.lastMouseY	= ey;

    drag.obj.root.onDrag(nx,ny);
    return false;
  },

  end : function()
  {
    document.onmousemove = null;
    document.onmouseup   = null;
    drag.obj.root.onDragEnd(parseInt(drag.obj.root.style[drag.obj.hmode ? "left":"right"]),parseInt(drag.obj.root.style[drag.obj.vmode ? "top":"bottom"]));
    drag.obj             = null;
  },

  fixevent : function(e)
  {
    if (typeof e        == 'undefined') e        = window.event;
    if (typeof e.layerX == 'undefined') e.layerX = e.offsetX;
    if (typeof e.layerY == 'undefined') e.layerY = e.offsetY;
    return e;
  }
};

var scroller =
{
  scrollid  : null,  // Scrollbar id
  scrolllen : 0,     // Length scroller
  scrolloff : 0,     // Zero offset for scroller
  scrollnsa : 0,     // Non-scrollbar area

  init: function()
  {
    var o = document.getElementById(scroller.scrollid+"scroller");
    o.scrollid = scroller.scrollid;

    // Collect the variables
    o.scrolldoclen  = document.getElementById(scroller.scrollid+"content")  .offsetWidth;
    o.scrollcontlen = document.getElementById(scroller.scrollid+"container").offsetWidth;
    o.scrollbarlen  = document.getElementById(scroller.scrollid+"scrollbar").offsetWidth-scroller.scrollnsa;

    if (scroller.scrolllen>0) o.scrolllen = scroller.scrolllen; else
    {
      o.scrolllen = (o.scrollcontlen*o.scrollbarlen)/o.scrolldoclen;
      if(o.scrolllen < 50) o.scrolllen = 50;
    }

    o.style.width = Math.round(o.scrolllen)+"px";
    
    // What is the effective scroll distance once the scoller's height has been taken into account
    o.scrolldist = Math.round(o.scrollbarlen-o.scrolllen);
    o.style.left = scroller.scrolloff+"px";
    
    // Make the scroller div draggable
    drag.init(o,null,scroller.scrolloff,o.scrolldist+scroller.scrolloff,0,0);
    
    // Add ondrag function
    o.onDrag = function (x,y)
    {
      var o       = this;
      var scrollY = parseInt(o.style.left)-scroller.scrolloff;
      var docY    = 0 - (scrollY*(o.scrolldoclen-o.scrollcontlen)/o.scrolldist);
      document.getElementById(o.scrollid+"content").style.left = docY+"px";
    }
  }
}