list.h

/* ScummVM - Graphic Adventure Engine
 *
 * ScummVM is the legal property of its developers, whose names
 * are too numerous to list here. Please refer to the COPYRIGHT
 * file distributed with this source distribution.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation, either version 3 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 */

#ifndef BAGEL_BOFLIB_LIST_H
#define BAGEL_BOFLIB_LIST_H

#include "common/scummsys.h"
#include "bagel/boflib/misc.h"

namespace Bagel {


#define MIN_NODES 5 // Minimum # of pre-allocated nodes in node array

template<class T>
class CBofListNode {
protected:
    T _cItem;              // Data contained at this node

public:
    CBofListNode() {
        _pNext = _pPrev = nullptr;
    }
    CBofListNode(T cItem) {
        _pNext = _pPrev = nullptr;
        _cItem = cItem;
    }

    T getNodeItem() {
        return _cItem;
    }
    void setNodeItem(T cItem) {
        _cItem = cItem;
    }

    CBofListNode *_pNext; // Next node in list
    CBofListNode *_pPrev; // Previous node in list
};

template<class T>
class CBofList {
private:
    void newItemList() {
        if (_pItemList != nullptr) {
            bofFree(_pItemList);
            _pItemList = nullptr;
        }

        if (_nNumItems != 0) {
            _pItemList = (void **)bofAlloc(_nNumItems * sizeof(void *));
        }
    }

    void killItemList() {
        if (_pItemList != nullptr) {
            bofFree(_pItemList);
            _pItemList = nullptr;
        }
    }

    void recalcItemList() {
        // We only want to recalc if we're about to overflow what we have
        if (_nNumItems >= _nItemsAllocated) {
            if (_pItemList != nullptr) {
                bofFree(_pItemList);
                _pItemList = nullptr;
            }

            if (_nNumItems != 0) {
                assert(_nItemsAllocated < 0x8000);
                _nItemsAllocated *= 2;
                if (_nItemsAllocated == 0)
                    _nItemsAllocated = MIN_NODES;

                _pItemList = (void **)bofAlloc(_nItemsAllocated * sizeof(void *));
            }
        }

        if (_nNumItems != 0) {
            assert(_pItemList != nullptr);

            int i = 0;
            CBofListNode<T> *pNode = _pHead;

            while (pNode != nullptr) {
                *(_pItemList + i++) = pNode;
                pNode = pNode->_pNext;
            }
        }
    }

    CBofListNode<T> *newNode(T cItem) {
        CBofListNode<T> *pNewNode = new CBofListNode<T>(cItem);
        return pNewNode;
    }

    CBofListNode<T> *getActualHead() {
        CBofListNode<T> *pNode;
        CBofListNode<T> *pLast = pNode = _pHead;

        while (pNode != nullptr) {
            pLast = pNode;
            pNode = pNode->_pPrev;
        }

        return pLast;
    }

    CBofListNode<T> *getActualTail() {
        CBofListNode<T> *pNode;
        CBofListNode<T> *pLast = pNode = _pTail;

        while (pNode != nullptr) {
            pLast = pNode;
            pNode = pLast->_pNext;
        }

        return pLast;
    }

protected:
    uint32 _nNumItems;
    uint32 _nItemsAllocated;
    CBofListNode<T> *_pHead;       // pointer to head of list
    CBofListNode<T> *_pTail;       // pointer to tail of list

    void **_pItemList;         // pointer to secondary node list

public:
    /*
     * Constructor
     */
    CBofList() {
        _nNumItems = 0;
        _nItemsAllocated = 0;
        _pHead = _pTail = nullptr;
        _pItemList = nullptr;
    }

    virtual ~CBofList() {
        removeAll();
        killItemList();
        assert(_nNumItems == 0);
    }

    int getCount() const {
        return _nNumItems;
    }

    int getActualCount() const {
        uint32 nCount = 0;
        CBofListNode<T> *pNode = _pHead;
        while (pNode != nullptr) {
            nCount++;
            pNode = pNode->_pNext;
        }

        // There should be no discrepancy
        assert(_nNumItems == nCount);

        return _nNumItems;
    }

    bool isEmpty() const {
        return _pHead == nullptr;
    }

    inline T getNodeItem(int nNodeIndex) {
        CBofListNode<T> *pNode = getNode(nNodeIndex);

        assert(pNode != nullptr);

        return pNode->getNodeItem();
    }

    void setNodeItem(int nNodeIndex, T tNewItem) {
        CBofListNode<T> *pNode = getNode(nNodeIndex);

        assert(pNode != nullptr);

        pNode->setNodeItem(tNewItem);
    }

    T operator[](int nIndex) {
        return getNodeItem(nIndex);
    }

    CBofListNode<T> *getNode(int nNodeIndex) {
        assert(nNodeIndex >= 0 && nNodeIndex < getCount());

        CBofListNode<T> *pNode;

        if (_pItemList == nullptr) {

            pNode = _pHead;
            while (pNode != nullptr) {
                if (nNodeIndex-- == 0)
                    break;
                pNode = pNode->_pNext;
            }

        } else {
            pNode = (CBofListNode<T> *)(*(_pItemList + nNodeIndex));
        }

        return pNode;
    }

    void insertBefore(int nNodeIndex, T cNewItem) {
        assert(!isEmpty());
        insertBefore(getNode(nNodeIndex), cNewItem);
    }

    void insertBefore(CBofListNode<T> *pNode, T cNewItem) {
        assert(pNode != nullptr);
        assert(!isEmpty());

        if (pNode == _pHead) {
            addToHead(cNewItem);
        } else {

            CBofListNode<T> *pNewNode = newNode(cNewItem);

            pNewNode->_pPrev = pNode->_pPrev;
            pNewNode->_pNext = pNode;

            if (pNode->_pPrev != nullptr)
                pNode->_pPrev->_pNext = pNewNode;

            pNode->_pPrev = pNewNode;
        }

        // one more item in list
        assert(_nNumItems != 0xFFFF);
        _nNumItems++;

        recalcItemList();
    }

    void insertAfter(int nNodeIndex, T cNewItem) {
        assert(!isEmpty());
        insertAfter(getNode(nNodeIndex), cNewItem);
    }

    void insertAfter(CBofListNode<T> *pNode, T cNewItem) {
        assert(pNode != nullptr);
        assert(!isEmpty());

        if (pNode == _pTail) {
            addToTail(cNewItem);
        } else {

            CBofListNode<T> *pNewNode = newNode(cNewItem);
            pNewNode->_pPrev = pNode;
            pNewNode->_pNext = pNode->_pNext;

            if (pNode->_pNext != nullptr)
                pNode->_pNext->_pPrev = pNewNode;

            pNode->_pNext = pNewNode;
        }

        // one more item in list
        assert(_nNumItems != 0xFFFF);
        _nNumItems++;

        recalcItemList();
    }

    T remove(CBofListNode<T> *pNode) {
        assert(pNode != nullptr);

        // One less item in list
        _nNumItems--;

        //assert(_nNumItems >= 0);

        if (pNode != nullptr) {

            T retVal = pNode->getNodeItem();

            if (_pHead == pNode)
                _pHead = _pHead->_pNext;

            if (_pTail == pNode)
                _pTail = _pTail->_pPrev;

            if (pNode->_pPrev != nullptr)
                pNode->_pPrev->_pNext = pNode->_pNext;

            if (pNode->_pNext != nullptr)
                pNode->_pNext->_pPrev = pNode->_pPrev;

            delete pNode;

            recalcItemList();
            return retVal;
        } else {
            return T();
        }
    }

    T remove(int nNodeIndex) {
        return remove(getNode(nNodeIndex));
    }

    void removeAll() {
        int i = getCount();

        while (i-- != 0)
            remove(0);
    }

    inline T removeHead() {
        assert(_pHead != nullptr);

        return remove(_pHead);
    }

    inline T removeTail() {
        assert(_pTail != nullptr);
        return remove(_pTail);
    }

    inline void addToHead(CBofListNode<T> *pNewNode) {
        assert(pNewNode != nullptr);

        pNewNode->_pNext = _pHead;
        pNewNode->_pPrev = nullptr;
        if (_pHead != nullptr)
            _pHead->_pPrev = pNewNode;
        _pHead = pNewNode;

        if (_pTail == nullptr)
            _pTail = _pHead;

        // one less item in list
        assert(_nNumItems != 0xFFFF);
        _nNumItems++;

        recalcItemList();
    }

    inline void addToHead(T cItem) {
        addToHead(newNode(cItem));
    }

    void addToTail(CBofListNode<T> *pNewNode) {
        assert(pNewNode != nullptr);

        pNewNode->_pPrev = _pTail;
        pNewNode->_pNext = nullptr;
        if (_pTail != nullptr)
            _pTail->_pNext = pNewNode;
        _pTail = pNewNode;

        if (_pHead == nullptr)
            _pHead = _pTail;

        // One more item in list
        assert(_nNumItems != 0xFFFF);
        _nNumItems++;
        recalcItemList();
    }

    void addToTail(T cItem) {
        addToTail(newNode(cItem));
    }

    CBofListNode<T> *getHead() const {
        return _pHead;
    }
    CBofListNode<T> *getTail() const {
        return _pTail;
    }
};

} // namespace Bagel

#endif