// File:	TCollection_List.gxx
// Created:	Thu Dec 17 16:10:17 1992
// Author:	Remi LEQUETTE
//		<rle@phobox>
// Revised:	Thu Jan 17 11:40:17 1995
// By:  	Mireille MERCIEN


#include <Standard_NoMoreObject.hxx>
#include <Standard_NoSuchObject.hxx>

//=======================================================================
//function : TCollection_List
//purpose  : 
//=======================================================================

TCollection_List::TCollection_List() :
       myFirst(NULL),
       myLast(NULL)
{}

//=======================================================================
//function : TCollection_List
//purpose  : 
//=======================================================================

TCollection_List::TCollection_List(const TCollection_List& Other) :
       myFirst(NULL),
       myLast(NULL)
{
  if (!Other.IsEmpty()) {
//    cout << "List copied : magic constructor"<<endl;
    TCollection_ListIterator It(Other);
    while (It.More()) {
      Append(It.Value());
      It.Next();
    }
  }
}

//=======================================================================
//function : Assign
//purpose  : 
//=======================================================================

void TCollection_List::Assign(const TCollection_List& Other) 
{
  if (this != &Other) { 
      Clear();
      TCollection_ListIterator It(Other);
      while (It.More()) {
          Append(It.Value());
          It.Next();
      }
  }
}

//=======================================================================
//function : Clear
//purpose  : 
//=======================================================================

void TCollection_List::Clear()
{
  TCollection_ListNode* p = (TCollection_ListNode*) myFirst;
  TCollection_ListNode* q;
  while (p != NULL) {
    q = p;
    p = (TCollection_ListNode*)q->Next();
    delete q;
  }
  myFirst = myLast = NULL;
}

//=======================================================================
//function : Extent
//purpose  : 
//=======================================================================

Standard_Integer TCollection_List::Extent() const
{
  Standard_Integer Size = 0;
  TCollection_ListNode* p = (TCollection_ListNode*) myFirst;
  while (p != NULL) {
    Size++;
    p = (TCollection_ListNode*)p->Next();
  }
  return Size;
}


//=======================================================================
//function : Prepend
//purpose  : 
//=======================================================================

void TCollection_List::Prepend(const Item& I)
{
  myFirst = new TCollection_ListNode(I,(TCollection_ListNode*)myFirst);
  if (myLast == NULL) myLast = myFirst;
}

//=======================================================================
//function : Prepend
//purpose  : 
//=======================================================================

void TCollection_List::Prepend(const Item& I, TCollection_ListIterator& theIt)
{
  myFirst = new TCollection_ListNode(I,(TCollection_ListNode*)myFirst);

  theIt.current  = myFirst;
  theIt.previous = NULL;
 
  if (myLast == NULL) myLast = myFirst;

}

//=======================================================================
//function : Prepend
//purpose  : 
//=======================================================================

void TCollection_List::Prepend(TCollection_List& Other)
{
  if (!Other.IsEmpty()) {
    ((TCollection_ListNode*)Other.myLast)->Next() = (TCollection_ListNode*)myFirst;
    myFirst = Other.myFirst;
    Other.myFirst = Other.myLast = NULL;
  }
}

//=======================================================================
//function : Append
//purpose  : 
//=======================================================================

void TCollection_List::Append(const Item& I)     
{
  TCollection_ListNode* p = new TCollection_ListNode(I,(TCollection_MapNode*)0L);

  if (myFirst == NULL) {
    myFirst = myLast = p;
  }
  else {
    ((TCollection_ListNode*)myLast)->Next() = (TCollection_ListNode*)p;
    myLast = p;
  }
}


//=======================================================================
//function : Append
//purpose  : 
//=======================================================================

void TCollection_List::Append(const Item& I, TCollection_ListIterator& theIt)
{
  TCollection_ListNode* p = new TCollection_ListNode(I,(TCollection_MapNode*)0L);

  theIt.current  = p;
  theIt.previous = myLast;

  if (myFirst == NULL) {
    myFirst = myLast = p;
  }
  else {
    ((TCollection_ListNode*)myLast)->Next() = (TCollection_ListNode*)p;
    myLast = p;
  }
}

//=======================================================================
//function : Append
//purpose  : 
//=======================================================================

void TCollection_List::Append(TCollection_List& Other)
{
  if (!Other.IsEmpty()) {
    if (IsEmpty()) {
      myFirst = Other.myFirst;
      myLast  = Other.myLast;
    }
    else {
      ((TCollection_ListNode*)myLast)->Next() = (TCollection_ListNode*)Other.myFirst;
      myLast = Other.myLast;
    }
    Other.myLast = Other.myFirst = NULL;
  }
}

//=======================================================================
//function : First
//purpose  : 
//=======================================================================

Item& TCollection_List::First() const
{
  Standard_NoSuchObject_Raise_if(myFirst == NULL,"List:First");
  return ((TCollection_ListNode*) myFirst)->Value();
}

//=======================================================================
//function : Last
//purpose  : 
//=======================================================================

Item& TCollection_List::Last() const
{
  Standard_NoSuchObject_Raise_if(myLast == NULL,"List:Last");
  return ((TCollection_ListNode*) myLast)->Value();
}

//=======================================================================
//function : RemoveFirst
//purpose  : 
//=======================================================================

void TCollection_List::RemoveFirst()
{
  if (myFirst == NULL) return;
  TCollection_ListNode* p = (TCollection_ListNode*) myFirst;
  myFirst = p->Next();
  delete p;
  if (myFirst == NULL) myLast = NULL;
}

//=======================================================================
//function : Remove
//purpose  : 
//=======================================================================

void TCollection_List::Remove(TCollection_ListIterator& It)
{
  Standard_NoSuchObject_Raise_if(!It.More(),
				 "TCollection_List::Remove");
  if (It.previous == NULL) {
    RemoveFirst();
    It.current = myFirst;
  }
  else {
    TCollection_ListNode* p =  (TCollection_ListNode*)((TCollection_ListNode*) It.current)->Next();
    ((TCollection_ListNode*)It.previous)->Next() = (TCollection_ListNode*)p;
    delete ((TCollection_ListNode*) It.current);
    It.current = p;
    if (p == NULL) myLast = It.previous;
  }
}

//=======================================================================
//function : InsertBefore
//purpose  : 
//=======================================================================

void TCollection_List::InsertBefore(const Item& I, 
				    TCollection_ListIterator& It)
{
  Standard_NoSuchObject_Raise_if(!It.More(), "TCollection_List::InsertBefore");
  if (It.previous == NULL) {
    Prepend(I);
    It.previous = myFirst;
  }
  else {
    TCollection_ListNode* p = new TCollection_ListNode(I,(TCollection_ListNode*)It.current);
    ((TCollection_ListNode*)It.previous)->Next() = (TCollection_ListNode*)p;
    It.previous = p;
  }
}

//=======================================================================
//function : InsertBefore
//purpose  : 
//=======================================================================

void TCollection_List::InsertBefore(TCollection_List& Other, 
				    TCollection_ListIterator& It)
{
  Standard_NoSuchObject_Raise_if(!It.More(), "TCollection_List::InsertBefore");
  if (!Other.IsEmpty()) {
    if (It.previous == NULL) {
      It.previous = Other.myLast;
      Prepend(Other);
    }
    else {
      ((TCollection_ListNode*)It.previous)->Next() = (TCollection_ListNode*)Other.myFirst;
      ((TCollection_ListNode*)Other.myLast)->Next() = (TCollection_ListNode*)It.current;
      It.previous = Other.myLast;
      Other.myLast = Other.myFirst = NULL;
    }
  }
}

//=======================================================================
//function : InsertAfter
//purpose  : 
//=======================================================================

void TCollection_List::InsertAfter(const Item& I, TCollection_ListIterator& It)
{
  Standard_NoSuchObject_Raise_if(!It.More(),"TCollection_List::InsertAfter");

  if (It.current == myLast)
    Append(I);
  else {
    TCollection_ListNode* p = new TCollection_ListNode(I,((TCollection_ListNode*)It.current)->Next());
    ((TCollection_ListNode*)It.current)->Next() = (TCollection_ListNode*)p;
  }
}

//=======================================================================
//function : InsertAfter
//purpose  : 
//=======================================================================

void TCollection_List::InsertAfter(TCollection_List& Other, 
				   TCollection_ListIterator& It)
{
  Standard_NoSuchObject_Raise_if(!It.More(),"TCollection_List::InsertAfter");

  if (It.current == myLast)
    Append(Other);
  else if (!Other.IsEmpty()) {
    ((TCollection_ListNode*)Other.myLast)->Next() = ((TCollection_ListNode*)It.current)->Next();
    ((TCollection_ListNode*)It.current)->Next() = (TCollection_ListNode*)Other.myFirst;
    Other.myLast = Other.myFirst = NULL;
  }
}


//=======================================================================
//function : TCollection_ListIterator
//purpose  : 
//=======================================================================

void TCollection_ListIterator::Next()
{
  Standard_NoMoreObject_Raise_if(current == NULL,
				 "TCollection_ListIteratorOfList");
  previous = current;
  current = ((TCollection_ListNode*)previous)->Next();
}

//=======================================================================
//function : Value
//purpose  : 
//=======================================================================

Item& TCollection_ListIterator::Value() const
{
  Standard_NoSuchObject_Raise_if(current == NULL,
				 "TCollection_ListIteratorOfList");
  return ((TCollection_ListNode*)current)->Value();
}