/*
 *   FILE: s5fs.h
 * AUTHOR: kma
 *  DESCR: shared structures for the System V file system...
 */

#pragma once

#ifdef __FSMAKER__
#include <stdint.h>
#else

#include "config.h"

#include "drivers/blockdev.h"
#include "fs/vfs.h"
#include "fs/vnode.h"
#include "mm/page.h"
#include "proc/kmutex.h"

#endif

#define S5_SUPER_BLOCK 0 /* the blockno of the superblock */
#define S5_IS_SUPER(blkno) ((blkno) == S5_SUPER_BLOCK)

#define S5_NBLKS_PER_FNODE 30

#define S5_BLOCK_SIZE 4096
#define S5_NDIRECT_BLOCKS 28
#define S5_INODES_PER_BLOCK (S5_BLOCK_SIZE / sizeof(s5_inode_t))
#define S5_DIRENTS_PER_BLOCK (S5_BLOCK_SIZE / sizeof(s5_dirent_t))
#define S5_MAX_FILE_BLOCKS (S5_NDIRECT_BLOCKS + S5_NIDIRECT_BLOCKS)
#define S5_MAX_FILE_SIZE (S5_MAX_FILE_BLOCKS * S5_BLOCK_SIZE)
#define S5_NAME_LEN 28

#define S5_TYPE_FREE 0x0
#define S5_TYPE_DATA 0x1
#define S5_TYPE_DIR 0x2
#define S5_TYPE_CHR 0x4
#define S5_TYPE_BLK 0x8

#define S5_MAGIC 071177
#define S5_CURRENT_VERSION 3

/* Number of blocks stored in the indirect block */
#define S5_NIDIRECT_BLOCKS (S5_BLOCK_SIZE / sizeof(uint32_t))

/* Given a file offset, returns the block number that it is in */
#define S5_DATA_BLOCK(seekptr) ((seekptr) / S5_BLOCK_SIZE)

/* Given a file offset, returns the offset into the pointer's block */
#define S5_DATA_OFFSET(seekptr) ((seekptr) % S5_BLOCK_SIZE)

/* Given an inode number, tells the block that inode is stored in. */
#define S5_INODE_BLOCK(inum) ((inum) / S5_INODES_PER_BLOCK + 1)

/*
 * Given an inode number, tells the offset (in units of s5_inode_t) of
 * that inode within the block returned by S5_INODE_BLOCK.
 */
#define S5_INODE_OFFSET(inum) ((inum) % S5_INODES_PER_BLOCK)

/* Given an FS struct, get the S5FS (private data) struct. */
#define FS_TO_S5FS(fs) ((s5fs_t *)(fs)->fs_i)

/* each node of the free block list looks like this: */
/*
typedef struct s5_fbl_node {
        int free_blocks[S5_NBLKS_PER_FNODE-1];
        int more;
} s5_fbl_node_t;
*/

/* Note that all on-disk types need to have hard-coded sizes (to ensure
 * inter-machine compatibility of s5 disks) */

/* The contents of the superblock, as stored on disk. */
typedef struct s5_super
{
    uint32_t s5s_magic;      /* the magic number */
    uint32_t s5s_free_inode; /* the free inode pointer */
    uint32_t s5s_nfree;      /* number of blocks currently in
                              * s5s_free_blocks */
    /* First "node" of free block list */
    uint32_t s5s_free_blocks[S5_NBLKS_PER_FNODE];

    uint32_t s5s_root_inode; /* root inode */
    uint32_t s5s_num_inodes; /* number of inodes */
    uint32_t s5s_version;    /* version of this disk format */
} s5_super_t;

/* The contents of an inode, as stored on disk. */
typedef struct s5_inode
{
    union {
        uint32_t s5_next_free; /* inode free list ptr */
        uint32_t s5_size;      /* file size */
    } s5_un;
    uint32_t s5_number;   /* this inode's number */
    uint16_t s5_type;     /* one of S5_TYPE_{FREE,DATA,DIR,CHR,BLK} */
    int16_t s5_linkcount; /* link count of this inode */
    uint32_t s5_direct_blocks[S5_NDIRECT_BLOCKS];
    uint32_t s5_indirect_block;
} s5_inode_t;

typedef struct s5_node
{
    vnode_t vnode;
    s5_inode_t inode;
    long dirtied_inode;
} s5_node_t;

#define VNODE_TO_S5NODE(vn) CONTAINER_OF(vn, s5_node_t, vnode)

/* The contents of a directory entry, as stored on disk. */
typedef struct s5_dirent
{
    uint32_t s5d_inode;
    char s5d_name[S5_NAME_LEN];
} s5_dirent_t;

#ifndef __FSMAKER__
/* Our in-memory representation of a s5fs filesytem (fs_i points to this) */
typedef struct s5fs
{
    blockdev_t *s5f_bdev;
    s5_super_t s5f_super;
    kmutex_t s5f_mutex;
    fs_t *s5f_fs;
#ifndef OLD
    mobj_t s5f_mobj;
#endif
} s5fs_t;

long s5fs_mount(struct fs *fs);

void s5_get_meta_disk_block(s5fs_t *s5fs, uint64_t blocknum, long forwrite,
                       pframe_t **pfp);

//void s5_get_file_disk_block(vnode_t *vnode, blocknum_t blocknum, long forwrite,
//                              pframe_t **pfp);

void s5_release_disk_block(pframe_t **pfp);

#endif