/**********************************************************
 Adapted from the sortable lists example by Tim Taylor
 http://tool-man.org/examples/sorting.html
 Modified by Tom Westcott : http://www.cyberdummy.co.uk 
 **********************************************************/

var DragDrop = {
  firstContainer : null,
  lastContainer : null,
  firstGContainer : null,
  lastGContainer : null,
  firstPontainer : null,
  lastPContainer : null,
  parent_id : null,
  source_id : null,
  parent_group : null,
  curContainer : null,
  makeListContainer : function(list, group, draggable, droppable) {
    // each container becomes a linked list node
    if (this.firstContainer == null) {
      this.firstContainer = this.lastContainer = list;
      list.previousContainer = null;
      list.nextContainer = null;
    } else {
      list.previousContainer = this.lastContainer;
      list.nextContainer = null;
      this.lastContainer.nextContainer = list;
      this.lastContainer = list;
    }
    
    list.draggable = draggable;
    list.droppable = droppable;

    if (draggable) {
      if (this.firstGContainer == null) {
        this.firstGContainer = this.lastGContainer = list;
        list.previousContainer = null;
        list.nextContainer = null;
      } else {
        list.previousContainer = this.lastGContainer;
        list.nextContainer = null;
        this.lastGContainer.nextContainer = list;
        this.lastGContainer = list;
      }
    }
    
    if (droppable) {
      if (this.firstPContainer == null) {
        this.firstPContainer = this.lastPContainer = list;
        list.previousContainer = null;
        list.nextContainer = null;
      } else {
        list.previousContainer = this.lastPContainer;
        list.nextContainer = null;
        this.lastPContainer.nextContainer = list;
        this.lastPContainer = list;
      }
    }
    
    // these functions are called when an item is draged over
    // a container or out of a container bounds.  onDragOut
    // is also called when the drag ends with an item having
    // been added to the container
    list.onDragOver = new Function();
    list.onDragOut = new Function();
    list.onDragDrop = new Function();
    list.group = group;
    
    var items = list.getElementsByTagName( "li" );
      
    if (draggable) {
      for (var i = 0; i < items.length; i++) {
        DragDrop.makeItemDraggable(items[i]);
      }
    }
  },
        
  serData : function ( group, theid ) {
    var container = DragDrop.firstContainer;
    var j = 0;
    var string = "";
                
    while (container != null) {
    
      if(theid != null && container.id != theid)
      {
        container = container.nextContainer;
        continue;
      }

      if(group != null && container.group != group)
      {
        container = container.nextContainer;
        continue;
      }
    
      j ++;
      if(j > 1)
      {
        string += ":";
      }
      string += container.id;
      
      var items = container.getElementsByTagName( "li" );
          string += "(";
      for (var i = 0; i < items.length; i++) {
          if(i > 0)
          {
            string += ",";
          }
    string += items[i].id;
      }
      string += ")";
      
      container = container.nextContainer;
    }
    return string;   
  },

  makeItemDraggable : function(item) {
    Drag.makeDraggable(item);
    item.setDragThreshold(5);
    
    // tracks if the item is currently outside all containers
    item.isOutside = false;
    
    item.onDragStart = DragDrop.onDragStart;
    item.onDrag = DragDrop.onDrag;
    item.onDragEnd = DragDrop.onDragEnd;
  },

  makeItemUnDraggable : function(item) {
    Drag.makeUnDraggable(item);
//    item.setDragThreshold(5);
    
    // tracks if the item is currently outside all containers
    item.isOutside = false;
    
    item.onDragStart = null;
    item.onDrag = null;
    item.onDragEnd = null;
  },

  onDragStart : function(nwPosition, sePosition, nwOffset, seOffset) {
    // update all container bounds, since they may have changed
    // on a previous drag
    //
    // could be more smart about when to do this
    var container = DragDrop.firstContainer;
    while (container != null) {
      container.northwest = Coordinates.northwestOffset( container, true );
      container.southeast = Coordinates.southeastOffset( container, true );
      container = container.nextContainer;
    }
    
    // item starts out over current parent
    this.parentNode.onDragOver();
    parent_id = this.parentNode.id;
    parent_group = this.parentNode.group;
curContainer = this.parentNode;
  },

  onDrag : function(nwPosition, sePosition, nwOffset, seOffset) {
    // check if we were nowhere
    if (this.isOutside) {
      // check each container to see if in its bounds
      var container = DragDrop.firstPContainer;
      while (container != null) {

//        if ((nwOffset.inside( container.northwest, container.southeast ) ||
//             seOffset.inside( container.northwest, container.southeast )) && container.group == parent_group) {
        if ((Drag.dmouse.inside( container.northwest, container.southeast )) && container.group == parent_group) {
          // we're inside this one
          container.onDragOver();
          this.isOutside = false;
//window.status = "Inside! 1";

curContainer = container;
//window.alert(this.newContainer+" "+this.newContainer.id+" "+this.newContainer.northwest);
    
          // since isOutside was true, the current parent is a
          // temporary clone of some previous container node and
          // it needs to be removed from the document
//          var tempParent = this.parentNode;
//          tempParent.removeChild( this );
//          container.appendChild( this );
//          tempParent.parentNode.removeChild( tempParent );
          break;
        }
        container = container.nextContainer;
      }
      // we're still not inside the bounds of any container
      if (this.isOutside)
        return;
    
    // check if we're outside our parent's bounds
//    } else if (!(nwOffset.inside( this.parentNode.northwest, this.parentNode.southeast ) ||
//      seOffset.inside( this.parentNode.northwest, this.parentNode.southeast ))) {
//    } else if (!(Drag.dmouse.inside( this.parentNode.northwest, this.parentNode.southeast ))) {
    } else if (this.parentNode && this.parentNode.northwest && !(Drag.dmouse.inside( this.parentNode.northwest, this.parentNode.southeast ))) {
      
      this.parentNode.onDragOut();
      this.isOutside = true;
      curContainer.onDragOut();      
curContainer = null;

      // check if we're inside a new container's bounds
      var container = DragDrop.firstPContainer;
      while (container != null) {
//        if ((nwOffset.inside( container.northwest, container.southeast ) ||
//             seOffset.inside( container.northwest, container.southeast )) && container.group == parent_group) {
        if ((Drag.dmouse.inside( container.northwest, container.southeast )) && container.group == parent_group) {
curContainer = container;
//window.status = "Inside! 2";
          // we're inside this one
          container.onDragOver();
          this.isOutside = false;
//          this.parentNode.removeChild( this );
//          container.appendChild( this );
          break;
        }
        container = container.nextContainer;
      }
      // if we're not in any container now, make a temporary clone of
      // the previous container node and add it to the document
      if (this.isOutside) {
//window.status = "Outside! 2 "+this.parentNode.id;
//        var tempParent = this.parentNode.cloneNode( false );
//        this.parentNode.removeChild( this );
//        tempParent.appendChild( this );
        // body puts a border or item at bottom of page if do not have this
//        tempParent.style.border = 0;
//        document.getElementsByTagName( "body" ).item(0).appendChild( tempParent );
//	curContainer = tempParent;
        return;
      }

    // See if we exited our current container
    } else if (curContainer && curContainer.northwest && (!Drag.dmouse.inside( curContainer.northwest, curContainer.southeast ))) {
//window.status = "Outside! 3";
      curContainer.onDragOut();
      this.isOutside = true;
      curContainer = null;
    }
    
return;

    // if we get here, we're inside some container bounds, so we do
    // everything the original dragsort script did to swap us into the
    // correct position
    
    var parent = this.parentNode;
  
    var item = this;
    var next = DragUtils.nextItem(item);
    while (next != null && this.offsetTop >= next.offsetTop - 2) {
      var item = next;
      var next = DragUtils.nextItem(item);
    }
    if (this != item) {
      DragUtils.swap(this, next);
      return;
    }

    var item = this;
    var previous = DragUtils.previousItem(item);
    while (previous != null && this.offsetTop <= previous.offsetTop + 2) {
      var item = previous;
      var previous = DragUtils.previousItem(item);
    }
    if (this != item) {
      DragUtils.swap(this, item);
      return;
    }
  },

  onDragEnd : function(nwPosition, sePosition, nwOffset, seOffset) {
    // if the drag ends and we're still outside all containers
    // it's time to remove ourselves from the document or add 
    // to the trash bin
    if (this.isOutside) {
      var container = DragDrop.firstContainer;
      while (container != null) {
         if(container.id == parent_id)
         {
           break;
         }
         container = container.nextContainer;
      }
      this.isOutside = false;

//      this.parentNode.removeChild( this );

      container.appendChild( this );

//var parent = this.parentNode;
//var parent = container;
//for (var i=0; i<parent.childNodes.length; i++) {
//  var kid = parent.childNodes[i];
//  if (this != kid) parent.removeChild(kid);
//}

      this.style["top"] = "0px";
      this.style["left"] = "0px";
      //var container = DragDrop.firstContainer;
      //container.appendChild( this );
      return;
    } else {

var pn = this.parentNode;
var container = DragDrop.firstContainer;
while (container != null) {
  if (container.id == parent_id) {
    break;
  }
  container = container.nextContainer;
}

    pn = curContainer;

//window.alert("dropped "+container.id+" on "+pn.id);
// pn = new parent, container = orig parent
if (pn.id != container.id) {
//          var tempParent = this.parentNode;
//          tempParent.removeChild( this );
//          container.appendChild( this );
//          if (tempParent.parentNode) tempParent.parentNode.removeChild( tempParent );
  var items = pn.getElementsByTagName( "li" );
  for (var i = 0; i < items.length; i++) {
    pn.removeChild(items[i]);
  }
  pn.appendChild(this);
  DragDrop.makeItemUnDraggable(this);

  // Restore copy to original spot
  var newnode = this.cloneNode(true);
  newnode.style["top"] = "0px";
  newnode.style["left"] = "0px";
  container.appendChild(newnode);
  DragDrop.makeItemDraggable(newnode);
}

    }
    this.parentNode.onDragOut();
    this.parentNode.onDragDrop();
    this.style["top"] = "0px";
    this.style["left"] = "0px";
  }
};

var DragUtils = {
  swap : function(item1, item2) {
    var parent = item1.parentNode;
    parent.removeChild(item1);
    parent.insertBefore(item1, item2);

    item1.style["top"] = "0px";
    item1.style["left"] = "0px";
  },

  replace : function(item1, item2) {
    var parent = item1.parentNode;
    parent.removeChild(item1);
    parent.appendChild(item2);

    item1.style["top"] = "0px";
    item1.style["left"] = "0px";
  },

  removeAllChildren : function(item) {
    var kids = item.childNodes;
    for (var i = 0; i < kids.length; i++) {
      item.removeChild(kids[i]);
    } 
  },


  nextItem : function(item) {
    var sibling = item.nextSibling;
    while (sibling != null) {
      if (sibling.nodeName == item.nodeName) return sibling;
      sibling = sibling.nextSibling;
    }
    return null;
  },

  previousItem : function(item) {
    var sibling = item.previousSibling;
    while (sibling != null) {
      if (sibling.nodeName == item.nodeName) return sibling;
      sibling = sibling.previousSibling;
    }
    return null;
  }
}