#pragma once
#include <kernel/types.h>
#include <kernel/vfs/mount.h>
#include <kernel/vfs/request.h>
#include <stddef.h>

enum handle_type {
	HANDLE_INVALID = 0,
	HANDLE_FILE,
	HANDLE_PIPE,
	HANDLE_FS_FRONT,
	HANDLE_FS_REQ,
	HANDLE_NULL,
};

// TODO use unions
// when making changes, keep in mind that dup creates copies of HANDLE_FILEs
struct Handle {
	enum handle_type type;
	VfsBackend *backend; /* HANDLE_FILE | HANDLE_FS_FRONT */
	void __user *file_id; /* only applicable to HANDLE_FILE */
	// TODO store flags instead
	bool readable, writeable; /* HANDLE_FILE | HANDLE_PIPE */
	VfsReq *req; /* HANDLE_FS_REQ */
	struct {
		Proc *queued;
		Handle *sister; // the other end, not included in refcount
	} pipe;
	Handle *base; /* used by dup'd HANDLE_FILEs. */

	size_t refcount;
};

Handle *handle_init(enum handle_type);
void handle_close(Handle *);