#include "arch/kernel/main.hpp"

#include "arch/exception_handling/assert.hpp"
#include "arch/memory/allocator/area_frame_allocator.hpp"
#include "arch/memory/multiboot/reader.hpp"
#include "arch/memory/paging/page_mapper.hpp"
#include "arch/memory/paging/temporary_page.hpp"
#include "arch/video/vga/text.hpp"

#include <algorithm>

namespace teachos::arch::kernel
{
  auto main() -> void
  {
    video::vga::text::clear();
    video::vga::text::cursor(false);
    video::vga::text::write("TeachOS is starting up...", video::vga::text::common_attributes::green_on_black);

    auto const memory_information = memory::multiboot::read_multiboot2();
    memory::allocator::area_frame_allocator allocator(memory_information);

    size_t address = 42 * memory::paging::PAGE_TABLE_ENTRY_COUNT * memory::paging::PAGE_TABLE_ENTRY_COUNT *
                     memory::allocator::PAGE_FRAME_SIZE;  // 42th P3 entry
    auto const page = memory::paging::virtual_page::containing_address(address);

    auto & active_table = memory::paging::active_page_table::create_or_get();
    memory::paging::temporary_page temp_page{page, allocator};
    temp_page.zero_entries(active_table);

    // memory::paging::map_next_free_page_to_frame(allocator, page, 0U);
    // auto optional_frame = memory::paging::translate_page(page);
    // video::vga::text::newline();
    // video::vga::text::write("Mapped physical frame: ", video::vga::text::common_attributes::green_on_black);
    // video::vga::text::write_number(optional_frame.value().frame_number,
    //                                video::vga::text::common_attributes::green_on_black);
    // video::vga::text::write(" to virtual page: ", video::vga::text::common_attributes::green_on_black);
    // video::vga::text::write_number(page.page_number, video::vga::text::common_attributes::green_on_black);

    // memory::paging::unmap_page(allocator, page);
    // video::vga::text::newline();
    // video::vga::text::write("Unapped virtual page from physical frame: ",
    //                         video::vga::text::common_attributes::green_on_black);
    // optional_frame = memory::paging::translate_page(page);
    // exception_handling::assert(!optional_frame.has_value(), "[Main] Ummapping failed");
    // video::vga::text::write_number(page.page_number, video::vga::text::common_attributes::green_on_black);

    auto last_allocated = allocator.allocate_frame();
    auto allocated = last_allocated;
    do
    {
      last_allocated = allocated;
      allocated = allocator.allocate_frame();
    } while (allocated);
    video::vga::text::newline();
    video::vga::text::write("Allocated Frames: ", video::vga::text::common_attributes::green_on_black);
    video::vga::text::write_number(last_allocated.value().frame_number,
                                   video::vga::text::common_attributes::green_on_black);
  }
}  // namespace teachos::arch::kernel