#ifndef PAGING_H
#define PAGING_H

#include "../include/stdio.h"
#include "../include/multiboot.h"
#include <stdint.h>

#define PAGE_OFFSET 0xC0000000
#define PAGE_SIZE		4096
#define PAGE_SHIFT		0x0C

#define PAGE_MASK		~(PAGE_SIZE - 1)	/* 0xFFFFF000 */
#define PAGE_ALIGN(addr)	(((addr) + (PAGE_SIZE - 1)) & PAGE_MASK)

#define PAGE_PRESENT 0x1
#define PAGE_RW		0x002	/* Read/Write */
#define PAGE_USER	0x004	/* User */
#define PAGE_NOALLOC	0x200	/* No Page Allocated (OS managed) */

#define GDT_BASE	(0xFFFFFFFF - (PAGE_OFFSET - 1))

#define GET_PGDIR(address)	((uint32_t)((address) >> 22) & 0x3FF)
#define GET_PGTBL(address)	((uint32_t)((address) >> 12) & 0x3FF)

// Общий размер памяти
#define MEMORY_SIZE (0xFFFFFFFF-0xC0000000)

// Количество страниц
#define PAGE_COUNT (MEMORY_SIZE / PAGE_SIZE)

// Размер битмапа в байтах (округлено вверх)
#define BITMAP_SIZE 1024//(PAGE_COUNT / 8)

extern uint32_t *kpage_dir;

//paging.c
void grub_memory_map(unsigned int magic, struct multiboot_info* mbi);
uint32_t* get_page_dir();
void set_page_dir(uint32_t new_page_dir);
uint32_t phys_to_virt(uint32_t phys);
uint32_t* create_page_dir();
void destroy_page_dir(uint32_t* page_dir);
uint32_t* copy_page_dir(uint32_t* page_dir_virt);

static inline uint32_t virt_to_phys(void* virt) {
    return (uint32_t)virt - 0xC0000000;
}

//page_alloc.c
int is_page_in_use(uint32_t page_index);
void set_bit(uint32_t page_index);
void clear_bit(uint32_t page_index);
void init_allocator();
void* alloc_page();
void free_page(void* physaddr);

//page_tables.c
void *get_physaddr(void *virtualaddr);
uint32_t get_pte(void *virtualaddr);
void map_page(void* physaddr, void* virtualaddr, unsigned int flags);
void unmap_page(void *virtualaddr);
int map_page_in_directory(uint32_t* pd_virt_addr, void* phys_addr, void* virt_addr, uint32_t flags);

#endif