file.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_FILE_H
#define BAGEL_BOFLIB_FILE_H

#include "common/algorithm.h"
#include "common/memstream.h"
#include "common/stream.h"
#include "bagel/boflib/stdinc.h"
#include "bagel/boflib/object.h"
#include "bagel/boflib/error.h"

namespace Bagel {

#define CBF_TEXT 0x00000001
#define CBF_BINARY 0x00000002
#define CBF_READONLY 0x00000004
#define CBF_OVERWRITE 0x00000008
#define CBF_SHARED 0x00000010
#define CBF_CREATE 0x00000020
#define CBF_SAVEFILE 0x100

#define CBF_DEFAULT (CBF_BINARY | CBF_READONLY)

#define CBOFFILE_TEXT CBF_TEXT
#define CBOFFILE_READONLY CBF_READONLY
#define CBOFFILE_OVERWRITE CBF_OVERWRITE

#define CBOFFILE_DEFAULT CBF_DEFAULT

class SaveReadStream : public Common::SeekableReadStream {
private:
    Common::MemoryWriteStreamDynamic *_owner;
public:
    SaveReadStream(Common::MemoryWriteStreamDynamic *owner) : _owner(owner) {}

    bool eos() const override {
        return _owner->pos() >= _owner->size();
    }
    uint32 read(void *dataPtr, uint32 dataSize) override {
        int bytesToCopy = MIN<int>(dataSize, _owner->size() - _owner->pos());
        const byte *src = _owner->getData() + _owner->pos();
        Common::copy(src, src + bytesToCopy, (byte *)dataPtr);
        seek(bytesToCopy, SEEK_CUR);
        return bytesToCopy;
    }
};

class SaveReadWriteStream : public Common::MemoryWriteStreamDynamic, SaveReadStream {
private:
    Common::WriteStream *_save;

public:
    SaveReadWriteStream(Common::WriteStream *save) :
        Common::MemoryWriteStreamDynamic(DisposeAfterUse::YES),
        SaveReadStream(this), _save(save) {
    }
    ~SaveReadWriteStream() {
        _save->write(getData(), Common::MemoryWriteStreamDynamic::size());
        delete _save;
    }

    int64 pos() const override {
        return Common::MemoryWriteStreamDynamic::pos();
    }
    bool seek(int64 offset, int whence = SEEK_SET) override {
        return Common::MemoryWriteStreamDynamic::seek(offset, whence);
    }
    int64 size() const override {
        return Common::MemoryWriteStreamDynamic::size();
    }
};

class CBofFile : public CBofObject, public CBofError {
protected:
    char _szFileName[MAX_FNAME];
    Common::Stream *_stream = nullptr;
    uint32 _lFlags = CBF_DEFAULT;

public:
    CBofFile();

    CBofFile(const char *pszFileName, uint32 lFlags = CBF_DEFAULT);

    virtual ~CBofFile();

    ErrorCode open(const char *pszFileName, uint32 lFlags = CBF_DEFAULT);

    ErrorCode create(const char *pszFileName, uint32 lFlags = CBF_DEFAULT | CBF_CREATE);

    virtual ErrorCode close();

    virtual ErrorCode read(void *pDestBuf, int32 lBytes);

    virtual ErrorCode write(const void *pSrcBuf, int32 lBytes);

    void commit();

    ErrorCode seek(uint32 lPos) {
        return (setPosition(lPos));
    }

    ErrorCode seekToBeginning() {
        return (setPosition(0));
    }

    ErrorCode seekToEnd();

    ErrorCode setPosition(uint32 lPos);

    uint32 getPosition();

    uint32 getLength();

    operator Common::SeekableReadStream *() const {
        return dynamic_cast<Common::SeekableReadStream *>(_stream);
    }
};

} // namespace Bagel

#endif