LSFramework/LSString/LSList.h

#pragma once
#include "LSMacros.h"
#include "LSListItem.h"

template <class T>

class LSList
{
public:
  LSList()
  {
  }

  ~LSList()
  {
    DELETE_ARRAY(m_pFirst)
    DELETE_ARRAY(m_pLast)
  }

  LSListItem<T>* Append(T tObj)
  {
    LSListItem<T>* pNewLast;
    if (!m_pFirst)
    {
      m_pFirst = new LSListItem<T>(tObj);
      m_pLast = new LSListItem<T>(tObj);
      m_pFirst->pNext = m_pLast;
      pNewLast = m_pFirst;
    }
    else
    {
      pNewLast = new LSListItem<T>(tObj);
      if (m_pLast->pBefore)
      {
        LSListItem<T>* pCurrentLast = m_pLast;
        pCurrentLast->pNext = pNewLast;
        pNewLast->pBefore = pCurrentLast;
      }
      else
      {
        m_pFirst->pNext = pNewLast;
        pNewLast->pBefore = m_pFirst;
      }
      m_pLast = pNewLast;
    }
    m_zSize++;
    return pNewLast;
  }

  LSListItem<T>* Remove(T tObj)
  {
    if (m_zSize == 0) return nullptr;

    LSListItem<T>* pItemToRemove = m_pFirst;

    while (pItemToRemove->tValue != tObj)
    {
      pItemToRemove = pItemToRemove->pNext;
    }

    LSListItem<T>* pRet = nullptr;

    if (m_zSize <= 1)
    {
      m_pFirst = nullptr;
      m_pLast = nullptr;
    }
    else if (pItemToRemove == m_pFirst)
    {
      LSListItem<T>* pNewFirst = pItemToRemove->pNext;
      pNewFirst->pBefore = nullptr;
      m_pFirst = pNewFirst;
      pRet = pNewFirst;
    }
    else if (pItemToRemove == m_pLast)
    {
      LSListItem<T>* pNewLast = pItemToRemove->pBefore;
      pNewLast->pNext = nullptr;
      m_pLast = pNewLast;
      pRet = pNewLast;
    }
    else
    {
      LSListItem<T>* pBefore = pItemToRemove->pBefore;
      LSListItem<T>* pNext = pItemToRemove->pNext;
      pBefore->pNext = pNext;
      pNext->pBefore = pBefore;
      pRet = pNext;
    }

    DELETE_POINTER(pItemToRemove);
    m_zSize--;
    return pRet;
  }

  T* RemoveAt(size_t zPos)
  {

  }

private:
  LSListItem<T>* m_pFirst = nullptr;
  LSListItem<T>* m_pLast = nullptr;

  size_t m_zSize = 0;
};