/* vim: tabstop=4 shiftwidth=4 noexpandtab
 */

#pragma once

#define PATH_SEPARATOR '/'
#define PATH_SEPARATOR_STRING "/"
#define PATH_UP  ".."
#define PATH_DOT "."

#define O_RDONLY     0x0000
#define O_WRONLY     0x0001
#define O_RDWR       0x0002
#define O_APPEND     0x0008
#define O_CREAT      0x0200
#define O_TRUNC      0x0400
#define O_EXCL       0x0800
#define O_NOFOLLOW   0x1000
#define O_PATH       0x2000

#define FS_FILE        0x01
#define FS_DIRECTORY   0x02
#define FS_CHARDEVICE  0x04
#define FS_BLOCKDEVICE 0x08
#define FS_PIPE        0x10
#define FS_SYMLINK     0x20
#define FS_MOUNTPOINT  0x40

#define _IFMT       0170000 /* type of file */
#define     _IFDIR  0040000 /* directory */
#define     _IFCHR  0020000 /* character special */
#define     _IFBLK  0060000 /* block special */
#define     _IFREG  0100000 /* regular */
#define     _IFLNK  0120000 /* symbolic link */
#define     _IFSOCK 0140000 /* socket */
#define     _IFIFO  0010000 /* fifo */

struct fs_node;

typedef uint32_t (*read_type_t) (struct fs_node *, uint32_t, uint32_t, uint8_t *);
typedef uint32_t (*write_type_t) (struct fs_node *, uint32_t, uint32_t, uint8_t *);
typedef void (*open_type_t) (struct fs_node *, unsigned int flags);
typedef void (*close_type_t) (struct fs_node *);
typedef struct dirent *(*readdir_type_t) (struct fs_node *, uint32_t);
typedef struct fs_node *(*finddir_type_t) (struct fs_node *, char *name);
typedef int (*create_type_t) (struct fs_node *, char *name, uint16_t permission);
typedef int (*unlink_type_t) (struct fs_node *, char *name);
typedef int (*mkdir_type_t) (struct fs_node *, char *name, uint16_t permission);
typedef int (*ioctl_type_t) (struct fs_node *, int request, void * argp);
typedef int (*get_size_type_t) (struct fs_node *);
typedef int (*chmod_type_t) (struct fs_node *, int mode);
typedef int (*symlink_type_t) (struct fs_node *, char * name, char * value);
typedef int (*readlink_type_t) (struct fs_node *, char * buf, size_t size);
typedef int (*selectcheck_type_t) (struct fs_node *);
typedef int (*selectwait_type_t) (struct fs_node *, void * process);
typedef int (*chown_type_t) (struct fs_node *, int, int);

typedef struct fs_node {
	char name[256];         /* The filename. */
	void * device;          /* Device object (optional) */
	uint32_t mask;          /* The permissions mask. */
	uint32_t uid;           /* The owning user. */
	uint32_t gid;           /* The owning group. */
	uint32_t flags;         /* Flags (node type, etc). */
	uint32_t inode;         /* Inode number. */
	uint32_t length;        /* Size of the file, in byte. */
	uint32_t impl;          /* Used to keep track which fs it belongs to. */
	uint32_t open_flags;    /* Flags passed to open (read/write/append, etc.) */

	/* times */
	uint32_t atime;         /* Accessed */
	uint32_t mtime;         /* Modified */
	uint32_t ctime;         /* Created  */

	/* File operations */
	read_type_t read;
	write_type_t write;
	open_type_t open;
	close_type_t close;
	readdir_type_t readdir;
	finddir_type_t finddir;
	create_type_t create;
	mkdir_type_t mkdir;
	ioctl_type_t ioctl;
	get_size_type_t get_size;
	chmod_type_t chmod;
	unlink_type_t unlink;
	symlink_type_t symlink;
	readlink_type_t readlink;

	struct fs_node *ptr;   /* Alias pointer, for symlinks. */
	uint32_t offset;       /* Offset for read operations XXX move this to new "file descriptor" entry */
	int32_t refcount;
	uint32_t nlink;

	selectcheck_type_t selectcheck;
	selectwait_type_t selectwait;

	chown_type_t chown;
} fs_node_t;

struct dirent {
	uint32_t ino;           /* Inode number. */
	char name[256];         /* The filename. */
};

struct stat  {
	uint16_t  st_dev;
	uint16_t  st_ino;
	uint32_t  st_mode;
	uint16_t  st_nlink;
	uint16_t  st_uid;
	uint16_t  st_gid;
	uint16_t  st_rdev;
	uint32_t  st_size;
	uint32_t  st_atime;
	uint32_t  __unused1;
	uint32_t  st_mtime;
	uint32_t  __unused2;
	uint32_t  st_ctime;
	uint32_t  __unused3;
	uint32_t  st_blksize;
	uint32_t  st_blocks;
};

struct vfs_entry {
	char * name;
	fs_node_t * file;
	char * device;
	char * fs_type;
};

extern fs_node_t *fs_root;
extern int pty_create(void *size, fs_node_t ** fs_master, fs_node_t ** fs_slave);

int has_permission(fs_node_t *node, int permission_bit);
uint32_t read_fs(fs_node_t *node, uint32_t offset, uint32_t size, uint8_t *buffer);
uint32_t write_fs(fs_node_t *node, uint32_t offset, uint32_t size, uint8_t *buffer);
void open_fs(fs_node_t *node, unsigned int flags);
void close_fs(fs_node_t *node);
struct dirent *readdir_fs(fs_node_t *node, uint32_t index);
fs_node_t *finddir_fs(fs_node_t *node, char *name);
int mkdir_fs(char *name, uint16_t permission);
int create_file_fs(char *name, uint16_t permission);
fs_node_t *kopen(char *filename, uint32_t flags);
char *canonicalize_path(char *cwd, char *input);
fs_node_t *clone_fs(fs_node_t * source);
int ioctl_fs(fs_node_t *node, int request, void * argp);
int chmod_fs(fs_node_t *node, int mode);
int chown_fs(fs_node_t *node, int uid, int gid);
int unlink_fs(char * name);
int symlink_fs(char * value, char * name);
int readlink_fs(fs_node_t * node, char * buf, size_t size);
int selectcheck_fs(fs_node_t * node);
int selectwait_fs(fs_node_t * node, void * process);

void vfs_install(void);
void * vfs_mount(char * path, fs_node_t * local_root);
typedef fs_node_t * (*vfs_mount_callback)(char * arg, char * mount_point);
int vfs_register(char * name, vfs_mount_callback callback);
int vfs_mount_type(char * type, char * arg, char * mountpoint);
void vfs_lock(fs_node_t * node);

/* Debug purposes only, please */
void debug_print_vfs_tree(void);

void map_vfs_directory(char *);

int make_unix_pipe(fs_node_t ** pipes);