#ifndef _VFS_H_INCLUDE
#define _VFS_H_INCLUDE

#include <sys/stat.h>
#include <hashtable.h>
#include <errno.h>

struct _vnode_t;
struct _fscalls_t;
struct _dirnode_t;

typedef struct {	
	struct _dirnode_t* rootvnode;
	struct _fscalls_t* calls;
	void* data;
} fs_t;


typedef struct _vnode_t {
	stat st;
	fs_t* fs;
	void* fsdata;
	size_t refcount;
	struct _dirnode_t* parent;
} vnode_t;

// folders are an expansion of vnode_t to save memory

typedef struct _dirnode_t{
	vnode_t vnode;
	struct _dirnode_t* mountednode;
	hashtable children;
} dirnode_t;

// fs specific calls called by the vfs on filesystems

typedef struct _fscalls_t {
	// prepares the filesystem using a filesystem data pointer and returns the root node
	dirnode_t* (*mount)(void*);
	// cleanup of the filesystem
	int	 (*umount)();
	//	 opens a file under a dirnode
	//	 args: parent, name
	int	 (*open)(dirnode_t*, char*);
	//	 cleans up a vfsnode
	//	 args: the node to clean
	int	 (*close)(vnode_t*);
	//	 creates a new directory with the right mode
	//	 args: parent, name, mode
	int	 (*mkdir)(dirnode_t* parent, char* name, mode_t mode);
	//	 create a new file
	//	 args: parent, name, mode
	int	 (*create)(dirnode_t* parent, char* name, mode_t mode);
} fscalls_t;


int vfs_mount(dirnode_t* ref, char* device, char* mountpoint, char* fs);
int vfs_umount(dirnode_t* ref, char* mountpoint);
int vfs_open(vnode_t* buf, dirnode_t* ref, char* path, int flags, mode_t mode);
int vfs_close(vnode_t* node);
int vfs_mkdir(dirnode_t* ref, char* path, mode_t mode);
int vfs_create(dirnode_t* ref, char* path, mode_t mode);


void vfs_init();
dirnode_t* vfs_root();
void vfs_acquirenode(vnode_t* node);
void vfs_releasenode(vnode_t* node);
vnode_t* vfs_newnode(fs_t* fs, void* fsdata);
dirnode_t* vfs_newdirnode(fs_t* fs, void* fsdata);
void vfs_destroynode(vnode_t* node);
int  vfs_resolvepath(vnode_t** result, dirnode_t* ref, char* path);

#endif