#include <stdint.h>

typedef struct page_map_level_4
{
    page_map_level_4_entry_t *map;
} page_map_level_4_t;

typedef struct page_map_level_4_entry {
    /// @brief Is this a valid entry?
    uint64_t present:1;
    /// @brief If clear, this page is read only;
    uint64_t writable:1;
    /// @brief If set, this page is user accessable;
    uint64_t user:1;
    /// @brief If set, write through caching is enabled
    uint64_t write_through:1;
    /// @brief Page will not be cached
    uint64_t cache_disable:1;
    /// @brief If set, this page has been recently accessed by the CPU
    uint64_t accessed:1;
    uint64_t unused_0:1;
    uint64_t reserved_0:1;
    uint64_t unused_1:4;
    /// @brief The address of the page directory pointer table
    uint64_t address:36;
    uint64_t reserved_1:4;
    uint64_t unused_2:11;
    uint64_t disable_execution:1;
} __attribute__((packed)) page_map_level_4_entry_t;

typedef struct page_directory_pointer_table
{
    page_directory_pointer_table_entry_t *map;
} page_directory_pointer_table_t;

typedef struct page_directory_pointer_table_entry {
    /// @brief Is this a valid entry?
    uint64_t present:1;
    /// @brief If clear, this page is read only;
    uint64_t writable:1;
    /// @brief If set, this page is user accessable;
    uint64_t user:1;
    /// @brief If set, write through caching is enabled
    uint64_t write_through:1;
    /// @brief Page will not be cached
    uint64_t cache_disable:1;
    /// @brief If set, this page has been recently accessed by the CPU
    uint64_t accessed:1;
    uint64_t unused_0:1;
    /// @brief Set to 0
    uint64_t page_size:1;
    uint64_t unused_1:4;
    /// @brief The address of the page directory pointer table
    uint64_t address:36;
    uint64_t reserved_1:4;
    uint64_t unused_2:11;
    uint64_t disable_execution:1;
} __attribute__((packed)) page_directory_pointer_table_entry_t;

typedef struct page_directory
{
    page_directory_entry_t *map;
} page_directory_t;

typedef struct page_directory_entry {
    /// @brief Is this a valid entry?
    uint64_t present:1;
    /// @brief If clear, this page is read only;
    uint64_t writable:1;
    /// @brief If set, this page is user accessable;
    uint64_t user:1;
    /// @brief If set, write through caching is enabled
    uint64_t write_through:1;
    /// @brief Page will not be cached
    uint64_t cache_disable:1;
    /// @brief If set, this page has been recently accessed by the CPU
    uint64_t accessed:1;
    uint64_t unused_0:1;
    /// @brief Set to 0
    uint64_t page_size:1;
    uint64_t unused_1:4;
    /// @brief The address of the page directory pointer table
    uint64_t address:36;
    uint64_t reserved_1:4;
    uint64_t unused_2:11;
    uint64_t disable_execution:1;
} __attribute__((packed)) page_directory_entry_t;

typedef struct page_table
{
    page_directory_entry_t *map;
} page_table_t;

typedef struct page_table_entry
{
    /// @brief Is this a valid entry?
    uint64_t present:1;
    /// @brief If clear, this page is read only;
    uint64_t writable:1;
    /// @brief If set, this page is user accessable;
    uint64_t user:1;
    /// @brief If set, write through caching is enabled
    uint64_t write_through:1;
    /// @brief Page will not be cached
    uint64_t cache_disable:1;
    /// @brief If set, this page has been recently accessed by the CPU
    uint64_t avalible:3;
    /// @brief The page has been written to
    uint64_t ditry:1;
    /// @brief Use Page Attribute Table
    uint64_t pat:1;
    uint64_t global:1;
    uint64_t unused_0:3;
    uint64_t address:36;
    uint64_t reserved:2;
    uint64_t unused_1:7;
    uint64_t protection_key:4;
    uint64_t execution_disable:1;
} __attribute__((packed)) page_table_entry_t;