//=========== (C) Copyright 1999 Valve, L.L.C. All rights reserved. ===========
//
// The copyright to the contents herein is the property of Valve, L.L.C.
// The contents may be used and/or copied only with the written permission of
// Valve, L.L.C., or in accordance with the terms and conditions stipulated in
// the agreement/contract under which the contents have been supplied.
//
// $Header: $
// $NoKeywords: $
//
// A growable array class that maintains a free list and keeps elements
// in the same location
//=============================================================================

#ifndef UTLVECTOR_H
#define UTLVECTOR_H

#ifdef _WIN32
#pragma once
#endif


#include <string.h>
#include "utlmemory.h"


//-----------------------------------------------------------------------------
// The CUtlVector class:
// A growable array class which doubles in size by default.
// It will always keep all elements consecutive in memory, and may move the
// elements around in memory (via a realloc) when elements are inserted or
// removed. Clients should therefore refer to the elements of the vector
// by index (they should *never* maintain pointers to elements in the vector).
//-----------------------------------------------------------------------------

template< class T >
class CUtlVector
{
public:
	typedef T ElemType_t;

	// constructor, destructor
	CUtlVector( int growSize = 0, int initSize = 0 );
	CUtlVector( T* pMemory, int numElements );
	~CUtlVector();
	
	// Copy the array.
	CUtlVector<T>& operator=( const CUtlVector<T> &other );

	// element access
	T& operator[]( int i );
	T const& operator[]( int i ) const;
	T& Element( int i );
	T const& Element( int i ) const;

	// Gets the base address (can change when adding elements!)
	T* Base();
	T const* Base() const;

	// Returns the number of elements in the vector
	// SIZE IS DEPRECATED!
	int Count() const;
	int Size() const;	// don't use me!

	// Is element index valid?
	bool IsValidIndex( int i ) const;
	static int InvalidIndex( void );

	// Adds an element, uses default constructor
	int AddToHead();
	int AddToTail();
	int InsertBefore( int elem );
	int InsertAfter( int elem );

	// Adds an element, uses copy constructor
	int AddToHead( T const& src );
	int AddToTail( T const& src );
	int InsertBefore( int elem, T const& src );
	int InsertAfter( int elem, T const& src );

	// Adds multiple elements, uses default constructor
	int AddMultipleToHead( int num );
	int AddMultipleToTail( int num, const T *pToCopy=NULL );	   
	int InsertMultipleBefore( int elem, int num, const T *pToCopy=NULL );	// If pToCopy is set, then it's an array of length 'num' and
	int InsertMultipleAfter( int elem, int num );

	// Calls RemoveAll() then AddMultipleToTail.
	void SetSize( int size );
	void SetCount( int count );
	
	// Calls SetSize and copies each element.
	void CopyArray( T const *pArray, int size );
	
	// Add the specified array to the tail.
	int AddVectorToTail( CUtlVector<T> const &src );

	// Finds an element (element needs operator== defined)
	int Find( T const& src ) const;

	bool HasElement( T const& src );

	// Makes sure we have enough memory allocated to store a requested # of elements
	void EnsureCapacity( int num );

	// Makes sure we have at least this many elements
	void EnsureCount( int num );

	// Element removal
	void FastRemove( int elem );	// doesn't preserve order
	void Remove( int elem );		// preserves order, shifts elements
	void FindAndRemove( T const& src );	// removes first occurrence of src, preserves order, shifts elements
	void RemoveMultiple( int elem, int num );	// preserves order, shifts elements
	void RemoveAll();				// doesn't deallocate memory

	// Memory deallocation
	void Purge();

	// Purges the list and calls delete on each element in it.
	void PurgeAndDeleteElements();

	// Set the size by which it grows when it needs to allocate more memory.
	void SetGrowSize( int size );

protected:
	// Can't copy this unless we explicitly do it!
	CUtlVector( CUtlVector const& vec ) { Assert(0); }

	// Grows the vector
	void GrowVector( int num = 1 );

	// Shifts elements....
	void ShiftElementsRight( int elem, int num = 1 );
	void ShiftElementsLeft( int elem, int num = 1 );

	// For easier access to the elements through the debugger
	void ResetDbgInfo();

	CUtlMemory<T> m_Memory;
	int m_Size;

	// For easier access to the elements through the debugger
	// it's in release builds so this can be used in libraries correctly
	T *m_pElements;
};


//-----------------------------------------------------------------------------
// For easier access to the elements through the debugger
//-----------------------------------------------------------------------------

template< class T >
inline void CUtlVector<T>::ResetDbgInfo()
{
	m_pElements = m_Memory.Base();
}

//-----------------------------------------------------------------------------
// constructor, destructor
//-----------------------------------------------------------------------------

template< class T >
inline CUtlVector<T>::CUtlVector( int growSize, int initSize )	: 
	m_Memory(growSize, initSize), m_Size(0)
{
	ResetDbgInfo();
}

template< class T >
inline CUtlVector<T>::CUtlVector( T* pMemory, int numElements )	: 
	m_Memory(pMemory, numElements), m_Size(0)
{
	ResetDbgInfo();
}

template< class T >
inline CUtlVector<T>::~CUtlVector()
{
	Purge();
}

template<class T>
inline CUtlVector<T>& CUtlVector<T>::operator=( const CUtlVector<T> &other )
{
	CopyArray( other.Base(), other.Count() );
	return *this;
}

//-----------------------------------------------------------------------------
// element access
//-----------------------------------------------------------------------------

template< class T >
inline T& CUtlVector<T>::operator[]( int i )
{
	Assert( IsValidIndex(i) );
	return m_Memory[i];
}

template< class T >
inline T const& CUtlVector<T>::operator[]( int i ) const
{
	Assert( IsValidIndex(i) );
	return m_Memory[i];
}

template< class T >
inline T& CUtlVector<T>::Element( int i )
{
	Assert( IsValidIndex(i) );
	return m_Memory[i];
}

template< class T >
inline T const& CUtlVector<T>::Element( int i ) const
{
	Assert( IsValidIndex(i) );
	return m_Memory[i];
}


//-----------------------------------------------------------------------------
// Gets the base address (can change when adding elements!)
//-----------------------------------------------------------------------------

template< class T >
inline T* CUtlVector<T>::Base()
{
	return m_Memory.Base();
}

template< class T >
inline T const* CUtlVector<T>::Base() const
{
	return m_Memory.Base();
}

//-----------------------------------------------------------------------------
// Count
//-----------------------------------------------------------------------------

template< class T >
inline int CUtlVector<T>::Size() const
{
	return m_Size;
}

template< class T >
inline int CUtlVector<T>::Count() const
{
	return m_Size;
}


//-----------------------------------------------------------------------------
// Is element index valid?
//-----------------------------------------------------------------------------

template< class T >
inline bool CUtlVector<T>::IsValidIndex( int i ) const
{
	return (i >= 0) && (i < m_Size);
}
 

//-----------------------------------------------------------------------------
// Returns in invalid index
//-----------------------------------------------------------------------------
template< class T >
inline int CUtlVector<T>::InvalidIndex( void )
{
	return -1;
}


//-----------------------------------------------------------------------------
// Grows the vector
//-----------------------------------------------------------------------------
template< class T >
void CUtlVector<T>::GrowVector( int num )
{
	if (m_Size + num - 1 >= m_Memory.NumAllocated())
	{
		m_Memory.Grow( m_Size + num - m_Memory.NumAllocated() );
	}

	m_Size += num;
	ResetDbgInfo();
}


//-----------------------------------------------------------------------------
// Makes sure we have enough memory allocated to store a requested # of elements
//-----------------------------------------------------------------------------
template< class T >
void CUtlVector<T>::EnsureCapacity( int num )
{
	m_Memory.EnsureCapacity(num);
	ResetDbgInfo();
}


//-----------------------------------------------------------------------------
// Makes sure we have at least this many elements
//-----------------------------------------------------------------------------
template< class T >
void CUtlVector<T>::EnsureCount( int num )
{
	if (Count() < num)
		AddMultipleToTail( num - Count() );
}


//-----------------------------------------------------------------------------
// Shifts elements
//-----------------------------------------------------------------------------
template< class T >
void CUtlVector<T>::ShiftElementsRight( int elem, int num )
{
	Assert( IsValidIndex(elem) || ( m_Size == 0 ) || ( num == 0 ));
	int numToMove = m_Size - elem - num;
	if ((numToMove > 0) && (num > 0))
		memmove( &Element(elem+num), &Element(elem), numToMove * sizeof(T) );
}

template< class T >
void CUtlVector<T>::ShiftElementsLeft( int elem, int num )
{
	Assert( IsValidIndex(elem) || ( m_Size == 0 ) || ( num == 0 ));
	int numToMove = m_Size - elem - num;
	if ((numToMove > 0) && (num > 0))
	{
		memmove( &Element(elem), &Element(elem+num), numToMove * sizeof(T) );

#ifdef _DEBUG
		Q_memset( &Element(m_Size-num), 0xDD, num * sizeof(T) );
#endif
	}
}

//-----------------------------------------------------------------------------
// Adds an element, uses default constructor
//-----------------------------------------------------------------------------

template< class T >
inline int CUtlVector<T>::AddToHead()
{
	return InsertBefore(0);
}

template< class T >
inline int CUtlVector<T>::AddToTail()
{
	return InsertBefore( m_Size );
}

template< class T >
inline int CUtlVector<T>::InsertAfter( int elem )
{
	return InsertBefore( elem + 1 );
}

template< class T >
int CUtlVector<T>::InsertBefore( int elem )
{
	// Can insert at the end
	Assert( (elem == Count()) || IsValidIndex(elem) );

	GrowVector();
	ShiftElementsRight(elem);
	Construct( &Element(elem) );
	return elem;
}


//-----------------------------------------------------------------------------
// Adds an element, uses copy constructor
//-----------------------------------------------------------------------------

template< class T >
inline int CUtlVector<T>::AddToHead( T const& src )
{
	return InsertBefore( 0, src );
}

template< class T >
inline int CUtlVector<T>::AddToTail( T const& src )
{
	return InsertBefore( m_Size, src );
}

template< class T >
inline int CUtlVector<T>::InsertAfter( int elem, T const& src )
{
	return InsertBefore( elem + 1, src );
}

template< class T >
int CUtlVector<T>::InsertBefore( int elem, T const& src )
{
	// Can insert at the end
	Assert( (elem == Count()) || IsValidIndex(elem) );

	GrowVector();
	ShiftElementsRight(elem);
	CopyConstruct( &Element(elem), src );
	return elem;
}


//-----------------------------------------------------------------------------
// Adds multiple elements, uses default constructor
//-----------------------------------------------------------------------------

template< class T >
inline int CUtlVector<T>::AddMultipleToHead( int num )
{
	return InsertMultipleBefore( 0, num );
}

template< class T >
inline int CUtlVector<T>::AddMultipleToTail( int num, const T *pToCopy )
{
	return InsertMultipleBefore( m_Size, num, pToCopy );
}

template< class T >
int CUtlVector<T>::InsertMultipleAfter( int elem, int num )
{
	return InsertMultipleBefore( elem + 1, num );
}


template< class T >
void CUtlVector<T>::SetCount( int count )
{
	RemoveAll();
	AddMultipleToTail( count );
}

template< class T >
inline void CUtlVector<T>::SetSize( int size )
{
	SetCount( size );
}

template< class T >
void CUtlVector<T>::CopyArray( T const *pArray, int size )
{
	SetSize( size );
	for( int i=0; i < size; i++ )
		(*this)[i] = pArray[i];
}

template< class T >
int CUtlVector<T>::AddVectorToTail( CUtlVector const &src )
{
	int base = Count();
	
	// Make space.
	AddMultipleToTail( src.Count() );

	// Copy the elements.	
	for ( int i=0; i < src.Count(); i++ )
		(*this)[base + i] = src[i];

	return base;
}

template< class T >
inline int CUtlVector<T>::InsertMultipleBefore( int elem, int num, const T *pToInsert )
{
	if( num == 0 )
		return elem;
	
	// Can insert at the end
	Assert( (elem == Count()) || IsValidIndex(elem) );

	GrowVector(num);
	ShiftElementsRight(elem, num);

	// Invoke default constructors
	for (int i = 0; i < num; ++i)
		Construct( &Element(elem+i) );

	// Copy stuff in?
	if ( pToInsert )
	{
		for ( int i=0; i < num; i++ )
		{
			Element( elem+i ) = pToInsert[i];
		}
	}

	return elem;
}

//-----------------------------------------------------------------------------
// Finds an element (element needs operator== defined)
//-----------------------------------------------------------------------------
template< class T >
int CUtlVector<T>::Find( T const& src ) const
{
	for ( int i = 0; i < Count(); ++i )
	{
		if (Element(i) == src)
			return i;
	}
	return -1;
}

template< class T >
bool CUtlVector<T>::HasElement( T const& src )
{
	return ( Find(src) >= 0 );
}

//-----------------------------------------------------------------------------
// Element removal
//-----------------------------------------------------------------------------

template< class T >
void CUtlVector<T>::FastRemove( int elem )
{
	Assert( IsValidIndex(elem) );

	Destruct( &Element(elem) );
	if (m_Size > 0)
	{
		memcpy( &Element(elem), &Element(m_Size-1), sizeof(T) );
		--m_Size;
	}
}

template< class T >
void CUtlVector<T>::Remove( int elem )
{
	Destruct( &Element(elem) );
	ShiftElementsLeft(elem);
	--m_Size;
}

template< class T >
void CUtlVector<T>::FindAndRemove( T const& src )
{
	int elem = Find( src );
	if ( elem != -1 )
	{
		Remove( elem );
	}
}

template< class T >
void CUtlVector<T>::RemoveMultiple( int elem, int num )
{
	Assert( IsValidIndex(elem) );
	Assert( elem + num <= Count() );

	for (int i = elem + num; --i >= elem; )
		Destruct(&Element(i));

	ShiftElementsLeft(elem, num);
	m_Size -= num;
}

template< class T >
void CUtlVector<T>::RemoveAll()
{
	for (int i = m_Size; --i >= 0; )
		Destruct(&Element(i));

	m_Size = 0;
}


//-----------------------------------------------------------------------------
// Memory deallocation
//-----------------------------------------------------------------------------

template< class T >
void CUtlVector<T>::Purge()
{
	RemoveAll();
	m_Memory.Purge( );
	ResetDbgInfo();
}


template<class T>
inline void CUtlVector<T>::PurgeAndDeleteElements()
{
	for( int i=0; i < m_Size; i++ )
		delete Element(i);

	Purge();
}


template< class T >
void CUtlVector<T>::SetGrowSize( int size )
{
	m_Memory.SetGrowSize( size );
}


#endif//UTLVECTOR_H