nod/include/nod/IFileIO.hpp

#ifndef __NOD_IFILE_IO__
#define __NOD_IFILE_IO__

#include <memory>
#include <functional>
#include <stdlib.h>
#include "IDiscIO.hpp"
#include "Util.hpp"

namespace nod
{

class IFileIO
{
public:
    virtual ~IFileIO() = default;
    virtual bool exists()=0;
    virtual uint64_t size()=0;

    struct IWriteStream : nod::IWriteStream
    {
        uint64_t copyFromDisc(IPartReadStream& discio, uint64_t length)
        {
            uint64_t read = 0;
            uint8_t buf[0x7c00];
            while (length)
            {
                uint64_t thisSz = nod::min(uint64_t(0x7c00), length);
                uint64_t readSz = discio.read(buf, thisSz);
                if (thisSz != readSz)
                {
                    LogModule.report(logvisor::Error, "unable to read enough from disc");
                    return read;
                }
                if (write(buf, readSz) != readSz)
                {
                    LogModule.report(logvisor::Error, "unable to write in file");
                    return read;
                }
                length -= thisSz;
                read += thisSz;
            }
            return read;
        }
        uint64_t copyFromDisc(IPartReadStream& discio, uint64_t length, const std::function<void(float)>& prog)
        {
            uint64_t read = 0;
            uint8_t buf[0x7c00];
            uint64_t total = length;
            while (length)
            {
                uint64_t thisSz = nod::min(uint64_t(0x7c00), length);
                uint64_t readSz = discio.read(buf, thisSz);
                if (thisSz != readSz)
                {
                    LogModule.report(logvisor::Error, "unable to read enough from disc");
                    return read;
                }
                if (write(buf, readSz) != readSz)
                {
                    LogModule.report(logvisor::Error, "unable to write in file");
                    return read;
                }
                length -= thisSz;
                read += thisSz;
                prog(read / float(total));
            }
            return read;
        }
    };
    virtual std::unique_ptr<IWriteStream> beginWriteStream() const=0;
    virtual std::unique_ptr<IWriteStream> beginWriteStream(uint64_t offset) const=0;

    struct IReadStream : nod::IReadStream
    {
        virtual uint64_t copyToDisc(struct IPartWriteStream& discio, uint64_t length)=0;
    };
    virtual std::unique_ptr<IReadStream> beginReadStream() const=0;
    virtual std::unique_ptr<IReadStream> beginReadStream(uint64_t offset) const=0;
};

std::unique_ptr<IFileIO> NewFileIO(SystemStringView path, int64_t maxWriteSize=-1);

}

#endif // __NOD_IFILE_IO__