/*
 * Copyright 2003-2013, Axel Dörfler, axeld@pinc-software.de.
 * Copyright 2008, François Revol <revol@free.fr>
 * Distributed under the terms of the MIT License.
 */


#include "File.h"

#include <sys/stat.h>
#include <unistd.h>

#include "Directory.h"


//#define TRACE(x) dprintf x
#define TRACE(x) do {} while (0)


namespace FATFS {


File::File(Volume &volume, off_t dirEntryOffset, uint32 cluster, off_t size,
        const char *name)
        :
        fVolume(volume),
        fStream(volume, cluster, size, name),
        fDirEntryOffset(dirEntryOffset)
{
        TRACE(("FATFS::File::()\n"));
}


File::~File()
{
        TRACE(("FATFS::File::~()\n"));
}


status_t
File::InitCheck()
{
        if (fStream.InitCheck() != B_OK)
                return fStream.InitCheck();

        return B_OK;
}


status_t
File::Open(void **_cookie, int mode)
{
        TRACE(("FATFS::File::%s(, %d)\n", __FUNCTION__, mode));
        if (fStream.InitCheck() < B_OK)
                return fStream.InitCheck();

        return Node::Open(_cookie, mode);
}


status_t
File::Close(void *cookie)
{
        return Node::Close(cookie);
}


ssize_t
File::ReadAt(void *cookie, off_t pos, void *buffer, size_t bufferSize)
{
        TRACE(("FATFS::File::%s(, %lld,, %d)\n", __FUNCTION__, pos, bufferSize));
        status_t err;
        err = fStream.ReadAt(pos, buffer, &bufferSize);
        if (err < B_OK)
                return err;
        return bufferSize;
}


ssize_t
File::WriteAt(void *cookie, off_t pos, const void *buffer, size_t bufferSize)
{
        off_t streamSize = fStream.Size();
        uint32 firstCluster = fStream.FirstCluster();

        // write data
        size_t written = bufferSize;
        status_t error = fStream.WriteAt(pos, buffer, &written);
        if (error != B_OK)
                return error;

        // If the file size has changed, we need to adjust the directory entry.
        if (fStream.Size() > streamSize || fStream.FirstCluster() != firstCluster) {
                error = Directory::UpdateDirEntry(fVolume, fDirEntryOffset,
                        fStream.FirstCluster(), fStream.Size());
                if (error != B_OK)
                        return error;
                        // TODO: Undo the changes!
        }

        return written;
}


status_t
File::GetName(char *nameBuffer, size_t bufferSize) const
{
        return fStream.GetName(nameBuffer, bufferSize);
}


status_t
File::GetFileMap(struct file_map_run *runs, int32 *count)
{
        return fStream.GetFileMap(runs, count);
}


int32
File::Type() const
{
        return S_IFREG;
}


off_t
File::Size() const
{
        return fStream.Size();
}


ino_t
File::Inode() const
{
        return fStream.FirstCluster() << 16;
}


}       // namespace FATFS