coll_templ.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/>.
 *
 */

/*
 * This file is based on WME Lite.
 * http://dead-code.org/redir.php?target=wmelite
 * Copyright (c) 2011 Jan Nedoma
 */

#ifndef WINTERMUTE_COLL_TEMPL_H
#define WINTERMUTE_COLL_TEMPL_H

#include "engines/wintermute/base/base_persistence_manager.h"

namespace Wintermute {

#include <new>

template<class TYPE>
inline void dcConstructElements(TYPE *pElements, int32 nCount) {
    // first do bit-wise zero initialization
    memset((void *)pElements, 0, nCount * sizeof(TYPE));

    // then call the constructor(s)
    for (; nCount--; pElements++)
        ::new((void *)pElements) TYPE;
}

template<class TYPE>
inline void dcDestructElements(TYPE *pElements, int32 nCount) {
    // call the destructor(s)
    for (; nCount--; pElements++)
        pElements->~TYPE();
}

template<class TYPE>
inline void dcCopyElements(TYPE *pDest, const TYPE *pSrc, int32 nCount) {
    // default is element-copy using assignment
    while (nCount--)
        *pDest++ = *pSrc++;
}

// BaseArray<TYPE>
template<class TYPE>
class BaseArrayBase {
public:
    // Construction
    BaseArrayBase();

    // Attributes
    int32 getSize() const;
    int32 getUpperBound() const;
    void setSize(int32 nNewSize, int32 nGrowBy = -1);

    // Operations
    // Clean up
    void freeExtra();
    void removeAll();

    // Accessing elements
    TYPE getAt(int32 nIndex) const;
    void setAt(int32 nIndex, TYPE newElement);
    TYPE& elementAt(int32 nIndex);

    // Direct Access to the element data (may return NULL)
    const TYPE *getData() const;
    TYPE *getData();

    // Potentially growing the array
    void setAtGrow(int32 nIndex, TYPE newElement);
    int32 add(TYPE newElement);
    int32 append(const BaseArrayBase &src);
    void copy(const BaseArrayBase &src);

    // overloaded operator helpers
    TYPE operator[](int32 nIndex) const;
    TYPE &operator[](int32 nIndex);

    // Operations that move elements around
    void insertAt(int32 nIndex, TYPE newElement, int32 nCount = 1);
    void removeAt(int32 nIndex, int32 nCount = 1);
    void insertAt(int32 nStartIndex, BaseArrayBase *pNewArray);

    // Implementation
protected:
    TYPE *_pData;   // the actual array of data
    int32 _nSize;     // # of elements (upperBound - 1)
    int32 _nMaxSize;  // max allocated
    int32 _nGrowBy;   // grow amount

public:
    ~BaseArrayBase();
};

// CBArray<TYPE> inline functions
template<class TYPE>
inline int32 BaseArrayBase<TYPE>::getSize() const {
    return _nSize;
}

template<class TYPE>
inline int32 BaseArrayBase<TYPE>::getUpperBound() const {
    return _nSize - 1;
}

template<class TYPE>
inline void BaseArrayBase<TYPE>::removeAll() {
    setSize(0, -1);
}

template<class TYPE>
inline TYPE BaseArrayBase<TYPE>::getAt(int32 nIndex) const {
    return _pData[nIndex];
}

template<class TYPE>
inline void BaseArrayBase<TYPE>::setAt(int32 nIndex, TYPE newElement) {
    _pData[nIndex] = newElement;
}

template<class TYPE>
inline TYPE &BaseArrayBase<TYPE>::elementAt(int32 nIndex) {
    return _pData[nIndex];
}

template<class TYPE>
inline const TYPE *BaseArrayBase<TYPE>::getData() const {
    return (const TYPE *)_pData;
}

template<class TYPE>
inline TYPE *BaseArrayBase<TYPE>::getData() {
    return (TYPE *)_pData;
}

template<class TYPE>
inline int32 BaseArrayBase<TYPE>::add(TYPE newElement) {
    int32 nIndex = _nSize;
    setAtGrow(nIndex, newElement);
    return nIndex;
}

template<class TYPE>
inline TYPE BaseArrayBase<TYPE>::operator[](int32 nIndex) const {
    return getAt(nIndex);
}

template<class TYPE>
inline TYPE &BaseArrayBase<TYPE>::operator[](int32 nIndex) {
    return elementAt(nIndex);
}

// BaseArray<TYPE, ARG_TYPE> out-of-line functions
template<class TYPE>
BaseArrayBase<TYPE>::BaseArrayBase() {
    _pData = nullptr;
    _nSize = _nMaxSize = _nGrowBy = 0;
}

template<class TYPE>
BaseArrayBase<TYPE>::~BaseArrayBase() {
    if (_pData != nullptr) {
        dcDestructElements<TYPE>(_pData, _nSize);
        delete[] (byte *)_pData;
    }
}

template<class TYPE>
void BaseArrayBase<TYPE>::setSize(int32 nNewSize, int32 nGrowBy) {
    if (nGrowBy != -1)
        _nGrowBy = nGrowBy;  // set new size

    if (nNewSize == 0) {
        // shrink to nothing
        if (_pData != nullptr) {
            dcDestructElements<TYPE>(_pData, _nSize);
            delete[] (byte *)_pData;
            _pData = nullptr;
        }
        _nSize = _nMaxSize = 0;
    } else if (_pData == nullptr) {
        // create one with exact size
        _pData = (TYPE *) new byte[nNewSize * sizeof(TYPE)];
        dcConstructElements<TYPE>(_pData, nNewSize);
        _nSize = _nMaxSize = nNewSize;
    } else if (nNewSize <= _nMaxSize) {
        // it fits
        if (nNewSize > _nSize) {
            // initialize the new elements
            dcConstructElements<TYPE>(&_pData[_nSize], nNewSize - _nSize);
        } else if (_nSize > nNewSize) {
            // destroy the old elements
            dcDestructElements<TYPE>(&_pData[nNewSize], _nSize - nNewSize);
        }
        _nSize = nNewSize;
    } else {
        // otherwise, grow array
        int32 numGrowBy = _nGrowBy;
        if (numGrowBy == 0) {
            // heuristically determine growth when nGrowBy == 0
            //  (this avoids heap fragmentation in many situations)
            numGrowBy = _nSize / 8;
            numGrowBy = (numGrowBy < 4) ? 4 : ((numGrowBy > 1024) ? 1024 : numGrowBy);
        }
        int nNewMax;
        if (nNewSize < _nMaxSize + numGrowBy)
            nNewMax = _nMaxSize + numGrowBy;  // granularity
        else
            nNewMax = nNewSize;  // no slush

        TYPE *pNewData = (TYPE *) new byte[nNewMax * sizeof(TYPE)];

        // copy new data from old
        memcpy(pNewData, _pData, _nSize * sizeof(TYPE));

        // construct remaining elements
        dcConstructElements<TYPE>(&pNewData[_nSize], nNewSize - _nSize);

        // get rid of old stuff (note: no destructors called)
        delete[] (byte *)_pData;
        _pData = pNewData;
        _nSize = nNewSize;
        _nMaxSize = nNewMax;
    }
}

template<class TYPE>
int32 BaseArrayBase<TYPE>::append(const BaseArrayBase &src) {
    int32 nOldSize = _nSize;
    setSize(_nSize + src._nSize);
    dcCopyElements<TYPE>(_pData + nOldSize, src._pData, src._nSize);
    return nOldSize;
}

template<class TYPE>
void BaseArrayBase<TYPE>::copy(const BaseArrayBase &src) {
    setSize(src._nSize);
    dcCopyElements<TYPE>(_pData, src._pData, src._nSize);
}

template<class TYPE>
void BaseArrayBase<TYPE>::freeExtra() {
    if (_nSize != _nMaxSize) {
        // shrink to desired size
        TYPE *pNewData = nullptr;
        if (_nSize != 0) {
            pNewData = (TYPE *) new byte[_nSize * sizeof(TYPE)];
            // copy new data from old
            memcpy(pNewData, _pData, _nSize * sizeof(TYPE));
        }

        // get rid of old stuff (note: no destructors called)
        delete[] (byte *)_pData;
        _pData = pNewData;
        _nMaxSize = _nSize;
    }
}

template<class TYPE>
void BaseArrayBase<TYPE>::setAtGrow(int32 nIndex, TYPE newElement) {
    if (nIndex >= _nSize)
        setSize(nIndex + 1, -1);
    _pData[nIndex] = newElement;
}

template<class TYPE>
void BaseArrayBase<TYPE>::insertAt(int32 nIndex, TYPE newElement, int32 nCount /*=1*/) {
    if (nIndex >= _nSize) {
        // adding after the end of the array
        setSize(nIndex + nCount, -1);   // grow so nIndex is valid
    } else {
        // inserting in the middle of the array
        int32 nOldSize = _nSize;
        setSize(_nSize + nCount, -1);  // grow it to new size
        // destroy intial data before copying over it
        dcDestructElements<TYPE>(&_pData[nOldSize], nCount);
        // shift old data up to fill gap
        memmove(&_pData[nIndex + nCount], &_pData[nIndex],
                (nOldSize - nIndex) * sizeof(TYPE));

        // re-init slots we copied from
        dcConstructElements<TYPE>(&_pData[nIndex], nCount);
    }

    // insert new value in the gap
    while (nCount--)
        _pData[nIndex++] = newElement;
}

template<class TYPE>
void BaseArrayBase<TYPE>::removeAt(int32 nIndex, int32 nCount) {
    // just remove a range
    int32 nMoveCount = _nSize - (nIndex + nCount);
    dcDestructElements<TYPE>(&_pData[nIndex], nCount);
    if (nMoveCount)
        memmove(&_pData[nIndex], &_pData[nIndex + nCount], nMoveCount * sizeof(TYPE));
    _nSize -= nCount;
}

template<class TYPE>
void BaseArrayBase<TYPE>::insertAt(int32 nStartIndex, BaseArrayBase *pNewArray) {
    if (pNewArray->getSize() > 0) {
        InsertAt(nStartIndex, pNewArray->getAt(0), pNewArray->getSize());
        for (int32 i = 0; i < pNewArray->getSize(); i++)
            setAt(nStartIndex + i, pNewArray->getAt(i));
    }
}

template<class TYPE>
class BaseArray : public BaseArrayBase<TYPE> {
public:
    bool persist(BasePersistenceManager *persistMgr) {
        int32 i, j;
        if (persistMgr->getIsSaving()) {
            j = BaseArray::getSize();
            persistMgr->transferSint32("ArraySize", &j);
            for (i = 0; i < j; i++) {
                TYPE obj = BaseArray::getAt(i);
                persistMgr->transferPtr("", &obj);
            }
        } else {
            BaseArray::setSize(0, -1);
            persistMgr->transferSint32("ArraySize", &j);
            for (i = 0; i < j; i++) {
                TYPE obj = nullptr;
                persistMgr->transferPtr("", &obj);
                BaseArray::add(obj);
            }
        }
        return true;
    }
};

template <>
class BaseArray<char *> : public BaseArrayBase<char *> {
public:
    bool persist(BasePersistenceManager *persistMgr) {
        int32 i, j;
        if (persistMgr->getIsSaving()) {
            j = getSize();
            persistMgr->transferSint32("ArraySize", &j);
            for (i = 0; i < j; i++) {
                char *obj = getAt(i);
                persistMgr->transferCharPtr("", &obj);
            }
        } else {
            setSize(0, -1);
            persistMgr->transferSint32("ArraySize", &j);
            for (i = 0; i < j; i++) {
                char *obj = nullptr;
                persistMgr->transferCharPtr("", &obj);
                add(obj);
            }
        }
        return true;
    }
};

template <>
class BaseArray<const char *> : public BaseArrayBase<const char *> {
public:
    bool persist(BasePersistenceManager *persistMgr) {
        int32 i, j;
        if (persistMgr->getIsSaving()) {
            j = getSize();
            persistMgr->transferSint32("ArraySize", &j);
            for (i = 0; i < j; i++) {
                const char * obj = getAt(i);
                persistMgr->transferConstChar("", &obj);
            }
        } else {
            setSize(0, -1);
            persistMgr->transferSint32("ArraySize", &j);
            for (i = 0; i < j; i++) {
                const char * obj;
                persistMgr->transferConstChar("", &obj);
                add(obj);
            }
        }
        return true;
    }
};

} // End of namespace Wintermute

#endif