/*****************************************************************************
 * Copyright (c) 2019, Nations Technologies Inc.
 *
 * All rights reserved.
 * ****************************************************************************
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met:
 *
 * - Redistributions of source code must retain the above copyright notice,
 * this list of conditions and the disclaimer below.
 *
 * Nations' name may not be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * DISCLAIMER: THIS SOFTWARE IS PROVIDED BY NATIONS "AS IS" AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT ARE
 * DISCLAIMED. IN NO EVENT SHALL NATIONS BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
 * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
 * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
 * EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * ****************************************************************************/

/**
 * @file dfs.h
 * @author Nations
 * @version v1.0.0
 *
 * @copyright Copyright (c) 2019, Nations Technologies Inc. All rights reserved.
 */
#ifndef __DFS_H__
#define __DFS_H__

#include <stdio.h>
#include <stdint.h>
#include <stdlib.h>
#include <string.h>

#include <time.h>
#include <rtthread.h>
#include <rtdevice.h>

#ifndef DFS_FILESYSTEMS_MAX
#define DFS_FILESYSTEMS_MAX     2
#endif

#ifndef DFS_FD_MAX
#define DFS_FD_MAX              4
#endif

/*
 * skip stdin/stdout/stderr normally
 */
#ifndef DFS_FD_OFFSET
#define DFS_FD_OFFSET           3
#endif

#ifndef DFS_PATH_MAX
#define DFS_PATH_MAX             256
#endif

#ifndef SECTOR_SIZE
#define SECTOR_SIZE              512
#endif

#ifndef DFS_FILESYSTEM_TYPES_MAX
#define DFS_FILESYSTEM_TYPES_MAX 2
#endif

#define DFS_FS_FLAG_DEFAULT     0x00    /* default flag */
#define DFS_FS_FLAG_FULLPATH    0x01    /* set full path to underlaying file system */

/* File types */
#define FT_REGULAR               0   /* regular file */
#define FT_SOCKET                1   /* socket file  */
#define FT_DIRECTORY             2   /* directory    */
#define FT_USER                  3   /* user defined */

/* File flags */
#define DFS_F_OPEN              0x01000000
#define DFS_F_DIRECTORY         0x02000000
#define DFS_F_EOF               0x04000000
#define DFS_F_ERR               0x08000000

#ifdef __cplusplus
extern "C" {
#endif

struct statfs
{
    size_t f_bsize;   /* block size */
    size_t f_blocks;  /* total data blocks in file system */
    size_t f_bfree;   /* free blocks in file system */
};

struct dirent
{
    uint8_t d_type;           /* The type of the file */
    uint8_t d_namlen;         /* The length of the not including the terminating null file name */
    uint16_t d_reclen;        /* length of this record */
    char d_name[DFS_PATH_MAX];   /* The null-terminated file name */
};

struct dfs_fdtable
{
    uint32_t maxfd;
    struct dfs_fd **fds;
};

/* Initialization of dfs */
int dfs_init(void);

char *dfs_normalize_path(const char *directory, const char *filename);
const char *dfs_subdir(const char *directory, const char *filename);

void dfs_lock(void);
void dfs_unlock(void);

/* FD APIs */
int fd_new(void);
struct dfs_fd *fd_get(int fd);
void fd_put(struct dfs_fd *fd);
int fd_is_open(const char *pathname);

struct dfs_fdtable *dfs_fdtable_get(void);

#ifdef __cplusplus
}
#endif

#endif