#ifndef _JOVE_HAL_MEMORY_H
#define _JOVE_HAL_MEMORY_H 1

#include "hal/obj.h"
#include "api/syscall.h"
#include "sys/syscall.h"
#include "lib/bitmap.h"
#include <stdbool.h>
#include <stdatomic.h>

typedef uintptr_t physaddr_t;
typedef uintptr_t virtaddr_t;
typedef unsigned short shmem_off_t;

/**Represents a region of alloc-able memory.
 * */
typedef struct jove_memory_region
{
    struct jove_memory_region *next;
    struct jove_memory_region *prev;
    atomic_flag lock;
    bool toplevel;
    struct bitmap bitmap;
} jove_region_t;

#define JOVE_REGION_GRANULARITY BITMAP_BLOCK_BITS
#define JOVE_REGION_OVERHEAD(pages) (sizeof(jove_region_t) + ((pages) + JOVE_REGION_GRANULARITY-1) / JOVE_REGION_GRANULARITY)

typedef struct jove_obj_untyped
{
    size_t limit;
} jove_untyped_t;

#define JOVE_UNTYPED_MINSIZE 0x10
#define JOVE_SMHEM_MAXPAGES 0xFFF

enum {
    JOVE_MAPPING_TYPE_UNTYPED = 0,
    JOVE_MAPPING_TYPE_SHMEM,
    JOVE_MAPPING_TYPE_MESSAGE
};

extern virtaddr_t __syscall_stack_guard;
extern virtaddr_t __syscall_stack;
extern virtaddr_t __interrupt_stack_guard;
extern virtaddr_t __interrupt_stack;

extern virtaddr_t *__syscall_stack_mapping;
extern virtaddr_t *__interrupt_stack_mapping;

void mem_setup_regions(void);

physaddr_t phys_fromvirt(virtaddr_t virt);
void *phys_tovirt(physaddr_t phys);

jove_region_t *region_from_addr(physaddr_t addr);
jove_region_t *region_data(jove_owned_obj_t *region_obj);
physaddr_t region_base(jove_owned_obj_t *region_obj);
unsigned int region_pages(jove_owned_obj_t *region_obj);
unsigned int region_freepages(jove_owned_obj_t *region_obj);

void region_new(jove_owned_obj_t *dest_obj, physaddr_t base, size_t pages);
int region_split(jove_owned_obj_t *source_obj, jove_owned_obj_t *dest_obj, size_t pages);
int region_release(jove_owned_obj_t *region_obj);

int region_alloc(jove_owned_obj_t *region_obj, jove_owned_obj_t *dest_obj);
int region_alloc_contig(jove_owned_obj_t *region_obj, jove_owned_obj_t *dest_obj, size_t pages);

uintptr_t untyped_address(jove_owned_obj_t *tgt);
size_t untyped_size(jove_owned_obj_t *tgt);

int untyped_split(jove_owned_obj_t *tgt, jove_owned_obj_t *dst, size_t bytes);
int untyped_merge(jove_owned_obj_t *a, jove_owned_obj_t *b);

int pagedir_new(jove_owned_obj_t *untyped_obj);

void pagedir_invlpg(virtaddr_t vptr);

virtaddr_t *pagedir_get_mapping(
        jove_owned_obj_t *pagedir, virtaddr_t vptr);

size_t pagedir_mapping_get_pfn(virtaddr_t *mapping);
virtaddr_t pagedir_ident_from_mapping(virtaddr_t *mapping);
bool pagedir_mapping_is_present(virtaddr_t *mapping);

void pagedir_mapping_set_pfn(virtaddr_t *mapping, size_t pfn);
void pagedir_mapping_set_present(virtaddr_t *mapping, bool present);
void pagedir_mapping_set_writeable(virtaddr_t *mapping, bool rw);
void pagedir_mapping_set_user(virtaddr_t *mapping, bool user);
void pagedir_mapping_set_type(virtaddr_t *mapping, int type);

int pagedir_map_untyped_frame(
        jove_owned_obj_t *tgt, jove_perm_obj_t *untyped_obj, 
        virtaddr_t vptr, struct syscall_pagedir_flags flg);
int pagedir_map_untyped_table(
        jove_owned_obj_t *tgt, jove_perm_obj_t *untyped_obj, 
        virtaddr_t vptr);
int pagedir_map_shmem_frame(
        jove_owned_obj_t *tgt, jove_perm_obj_t *shmem_obj, uint8_t page_offset,
        virtaddr_t vptr, struct syscall_pagedir_flags flg);

int pagedir_unmap_untyped_frame(
        jove_owned_obj_t *tgt, jove_owned_obj_t *dst, uintptr_t vptr);
int pagedir_unmap_untyped_table(
        jove_owned_obj_t *tgt, jove_owned_obj_t *dst, uintptr_t vptr);
int pagedir_unmap_shmem_frame(
        jove_owned_obj_t *tgt, uintptr_t vptr);

int shmem_new(jove_owned_obj_t *untyped_obj);

#endif