#ifndef _PAGETABLE_H_
#define _PAGETABLE_H_

#include "../types.h"

#define KERNEL_MEMORY_BORDER 0x4000000

typedef struct {
    uint8_t present:1 = 0;
    uint8_t write:1 = 0;
    uint8_t user:1 = 0;
    uint8_t pwt:1 = 0;
    uint8_t cache_disable:1 = 0;
    uint8_t accessed:1 = 0;
    uint8_t dirty:1 = 0;
    uint8_t pat:1 = 0;
    uint8_t rsvd_0:4 = 0;
    uint64_t address:39 = 0;
    uint16_t rsvd_1:10 = 0;
    uint8_t execute_disable:1 = 0;
} __attribute__((__packed__)) pagetable_entry_t;

typedef struct {
    pagetable_entry_t entries[512];
} pagetable_t;

//typedef struct {
//    uint8_t present:1 = 0;
//    uint8_t write:1 = 0;
//    uint8_t user:1 = 0;
//    uint8_t pwt:1 = 0;
//    uint8_t cache_disable:1 = 0;
//    uint8_t accessed:1 = 0;
//    uint8_t rsvd_0:6 = 0;
//    uint64_t address:39 = 0;
//    uint16_t rsvd_1:10 = 0;
//    uint8_t execute_disable:1 = 0;
//} __attribute__((__packed__))  pagedirectory_entry_t;

typedef struct {
    pagetable_t* l4;
    pagetable_t* l3;
    pagetable_t* l2;
    pagetable_t* l1_kernel;
    pagetable_t* l2_apic;
    pagetable_t* ioapic;
    pagetable_t* lapic;
} four_lvl_paging_t;

void write_identity_map(pagetable_t* identity_table, uint64_t size);
void create_basic_page_table(four_lvl_paging_t* table, pagetable_t* kernel_identity);
void load_cr3(void* cr3_value);
void setMapping(uintptr_t vaddr, void* frame, pagetable_t* l4, bool write=true, bool remap=false);
uintptr_t isMapped(uintptr_t vaddr, pagetable_t* l4);
void* getFreeVirtSpace(pagetable_t* l4, uint8_t num_pages);
void copy_pagetable(four_lvl_paging_t* parent_table, four_lvl_paging_t* child_table);
bool copy_page(pagetable_t* l4, uintptr_t src_paddr, void* dest_vaddr);

//typedef struct {
// same
//} pagedirectory_pointertable_entry_t;

//typedef struct {
// same
//} PML4_entry_t;

#endif