/*
 * Copyright 2008, Haiku, Inc.
 * Distributed under the terms of the MIT License.
 *
 * Authors:
 *              François Revol <revol@free.fr>
 */
#ifndef STREAM_H
#define STREAM_H

#include "fatfs.h"
#include "Volume.h"

#include <sys/stat.h>

#define CLUSTER_MAP_CACHE_SIZE 50

class Node;

struct file_map_run;

namespace FATFS {

class Stream {
        public:
                Stream(Volume &volume, uint32 chain, off_t size, const char *name);
                ~Stream();

                status_t InitCheck();
                Volume &GetVolume() const { return fVolume; }

                status_t GetName(char *nameBuffer, size_t bufferSize) const;
                status_t GetFileMap(struct file_map_run *runs, int32 *count);
                off_t   Size() const { return fSize; }
                uint32  FirstCluster() const { return fFirstCluster; }

                void    SetSize(off_t size)             { fSize = size; }

                status_t ReadAt(off_t pos, void *buffer, size_t *length,
                                        off_t *diskOffset = NULL);
                status_t WriteAt(off_t pos, const void *buffer, size_t *length,
                                        off_t *diskOffset = NULL);

        private:
                status_t                BuildClusterList();
                status_t                _FindCluster(off_t pos, uint32& _cluster);
                status_t                _FindOrCreateCluster(off_t pos, uint32& _cluster,
                                                        bool& _added);
                status_t                FindBlock(off_t pos, off_t &block, off_t &offset);

                Volume                  &fVolume;
                uint32                  fFirstCluster;
                uint32                  fClusterCount;
                //uint32                        *fClusters; // [fClusterCount]
                struct {
                        off_t block;
                        uint32 cluster;
                }                       fClusterMapCache[CLUSTER_MAP_CACHE_SIZE];
                int                     fClusterMapCacheLast;
                off_t                   fSize;
                // we cache the name here, since FAT doesn't have inodes,
                // let alone names inside.
                char                    fName[FATFS_NAME_LENGTH+1];
};

}       // namespace FATFS

#endif  /* STREAM_H */