/*
 * Copyright 2020, Shubham Bhagat, shubhambhagat111@yahoo.com
 * All rights reserved. Distributed under the terms of the MIT License.
 */
#ifndef __SHORT_DIR_H__
#define __SHORT_DIR_H__


#include "Directory.h"
#include "Inode.h"


/*
 * offset into the literal area
 * xfs_dir2_sf_off_t
 */
struct ShortFormOffset {
                        uint16                          i;
} __attribute__((packed));

//xfs_dir2_inou_t
union ShortFormInodeUnion {
                        uint64                          i8;
                        uint32                          i4;
} __attribute__((packed));


// xfs_dir2_sf_hdr_t
struct ShortFormHeader {
                        uint8                           count;
                                // number of entries
                        uint8                           i8count;
                                // # of 64bit inode entries
                        ShortFormInodeUnion     parent;
                                // absolute inode # of parent
} __attribute__((packed));


//xfs_dir2_sf_entry_t
struct ShortFormEntry {
                        uint8                           namelen;
                                // length of the name, in bytes
                        ShortFormOffset         offset;
                                // offset tag, for directory iteration
                        char                            name[];
                                // name of directory entry
/*
 * Following will be a single byte file type variable
 * and inode number (64bits or 32 bits)
 */
} __attribute__((packed));


class ShortDirectory : public DirectoryIterator {
public:
                                                                ShortDirectory(Inode* inode);
                                                                ~ShortDirectory();
                        size_t                          HeaderSize();
                        uint8                           GetFileType(ShortFormEntry* entry);
                        ShortFormEntry*         FirstEntry();
                        xfs_ino_t                       GetIno(ShortFormInodeUnion* inum);
                        xfs_ino_t                       GetEntryIno(ShortFormEntry* entry);
                        size_t                          EntrySize(int namelen);
                        status_t                        Rewind();
                        status_t                        GetNext(char* name, size_t* length,
                                                                        xfs_ino_t* ino);
                        status_t                        Lookup(const char* name, size_t length,
                                                                        xfs_ino_t* id);
private:
                        Inode*                          fInode;
                        ShortFormHeader*        fHeader;
                        uint16                          fLastEntryOffset;
                        // offset into the literal area
                        uint8                           fTrack;
                        // Takes the values 0, 1 or 2
};

#endif