/**************************************************
 * dom-drag.js
 * 09.25.2001
 * www.youngpup.net
 **************************************************
 * 10.28.2001 - fixed minor bug where events
 * sometimes fired off the handle, not the root.
 **************************************************/
 
 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.fixE(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.fixE(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;
 },
 
 fixE : 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;
 }};