// Copyright: 	Matra-Datavision 1991
// File:	TCollection_AVLSearchTree.gxx
// Created:	Thu May 23 16:57:42 1991
// Author:	Jean-Pierre TIRAULT
//		Transient implementation
//

#include <Standard_Address.hxx>           

// Global variable
static Standard_Address LastNode;                
// Global variable


void TCollection_AVLIterator::InOrderTraversal (const Standard_Address A)  {
  if (A) {
    InOrderTraversal (((TCollection_AVLNode*)A)->Left());
    TCollection_AVLList* S     = new TCollection_AVLList;
    S->Value()       = ((TCollection_AVLNode*)A)->Value();
    if (!FirstNode) { 
      FirstNode = (Standard_Address*)S; 
      LastNode = FirstNode; 
    }
    else { 
      ((TCollection_AVLList*)LastNode)->Next() = S;
      LastNode = (Standard_Address)S; 
    }
    InOrderTraversal (((TCollection_AVLNode*)A)->Right());
  }
}   




//-----------------------------------------------------------------------------
TCollection_AVLIterator::
              TCollection_AVLIterator ( const TCollection_AVLSearchTree& aTree) 
{
  LastNode  = FirstNode = NULL;
  Standard_Address Root = (Standard_Address) aTree.GetRoot();     // Current node = root of tree
  if (!Root) {
    HasMore = Standard_False;
  }
  else {
    HasMore = Standard_True;
    InOrderTraversal(Root);
  }
}
//-----------------------------------------------------------------------------
TCollection_AVLIterator::TCollection_AVLIterator ( const TCollection_AVLSearchTree&   aTree, const Item&   anItem) 
{
  LastNode  = FirstNode = NULL;
  Standard_Address  Root;
  
  if (aTree.Find(anItem,Root)) {
    HasMore = Standard_True;
    InOrderTraversal(Root);
  }
  else {   
    HasMore = Standard_False;
  }
}

//-----------------------------------------------------------------------------
void TCollection_AVLIterator::Clear () 
{
  LastNode     = NULL ;
  TCollection_AVLList* S   = (TCollection_AVLList*)FirstNode;
  TCollection_AVLList* P;
  while (S) {     // Memory management
    P = S;
    S = (TCollection_AVLList*)S->Next();
    delete P;
  }
  FirstNode    = NULL ;
  HasMore      = Standard_False;
}

//-----------------------------------------------------------------------------
const Item& TCollection_AVLIterator::Value () const 
{
  Standard_NoSuchObject_Raise_if(!HasMore,"TCollection_AVLIterator - No more object");
  return ((TCollection_AVLList*)FirstNode)->Value();
}

//-----------------------------------------------------------------------------
void TCollection_AVLIterator::Next () 
{
  Standard_NoSuchObject_Raise_if(!HasMore,"TCollection_AVLIterator - No more object");
  TCollection_AVLList* S = (TCollection_AVLList*)FirstNode;
  FirstNode  = ((TCollection_AVLList*)FirstNode)->Next();
  HasMore    = (FirstNode != NULL);
  delete S;
}