#ifndef _JOVE_ARCH_HAL_OBJ_H
#define _JOVE_ARCH_HAL_OBJ_H 1

#include <stdatomic.h>
#include <stdint.h>
#include <stddef.h>

enum
{
    JOVE_OBJ_SERIAL_COM = 0x80,
};

/*Represents a locked kernel object pointer inside of a object directory.*/
typedef union jove_obj
{
    struct {
        uint8_t type;
        atomic_flag lock;
        /*Raw value or pointer to a data-structure located in kernel memory.*/
        uint64_t value : 48;
    };
    uintmax_t data;
} jove_obj_t;

/*Represents an unlocked kernel object pointer.
 *This object should only exist temporarily while accessing the underlying
 *structure this object points to.*/
typedef union jove_obj_locked
{
    struct {
        uint8_t type;
        uint8_t lock;
        uint64_t value : 48;
    };
    uintmax_t data;
} jove_owned_obj_t;

/*Object directories are always 1 page wide. Since an object inside the directory
 * is a pointer width, on x86_64 that is 512 entries per directory.*/
#define JOVE_OBJDIR_SIZE 0x1000
#define JOVE_OBJDIR_ENTRIES (JOVE_OBJDIR_SIZE / sizeof(jove_obj_t))

typedef struct jove_objdir
{
    jove_obj_t entries[JOVE_OBJDIR_ENTRIES];
} jove_objdir_t;
/*Locks the mutex of the kernel object provided. Returns the locked version. */
jove_owned_obj_t *obj_take(jove_obj_t *obj);
/*Unlocks the mutex of the kernel object provided. Returns the unlocked version. */
jove_obj_t *obj_release(jove_owned_obj_t *obj);

/*Converts the value pointer of the object into a pointer to kernel memory.*/
void *obj_deref(jove_owned_obj_t *obj);

/*Getters and setters for accessing the type field of the kernel object. */
uint8_t obj_gettype(jove_owned_obj_t *obj);
void obj_settype(jove_owned_obj_t *obj, uint8_t type);

/*Getters and setters for accessing the value field of the kernel object. */
uintmax_t obj_getvalue(jove_owned_obj_t *obj);
void obj_setvalue(jove_owned_obj_t *obj, uintmax_t value);

/*Returns the n'th entry of the object directory passed.
 * If the passed object is not an objdir, returns NULL and sets errno to EBADOBJ.
 * If the passed entry index is out of bounds, returns NULL and sets errno to EOOB.*/
jove_owned_obj_t *objdir_getlocal(jove_owned_obj_t *objdir_obj, uint16_t entry);

/*Recursively seeks through an object directory for an object following the passed
 * path variable.
 * If the path length is zero, returns the passed object.
 * If the passed object is not an objdir, returns NULL and sets errno to EBADOBJ.
 * If any object excluding the object at the end of the path is not an objdir,
 * returns NULL and sets errno to EBADOBJ.
 * If any entry in the path is out of bounds, returns NULL and sets errno to EBADOBJ.*/
jove_owned_obj_t *objdir_getobj(jove_owned_obj_t *objdir_obj, const uint16_t *path, size_t path_len);

#endif