#include "arch/kernel/main.hpp"

#include "arch/exception_handling/assert.hpp"
#include "arch/memory/allocator/area_frame_allocator.hpp"
#include "arch/memory/cpu/msr.hpp"
#include "arch/memory/multiboot/reader.hpp"
#include "arch/memory/paging/kernel_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);

    memory::cpu::set_cr2_bit(memory::cpu::cr2_flags::WRITE_PROTECT);
    memory::cpu::set_efer_bit(memory::cpu::efer_flags::NXE);

    memory::paging::kernel_mapper kernel(allocator, memory_information);
    auto & active_table = kernel.remap_kernel();
    auto x = active_table.active_handle.next_table(0);
    auto y = x.value().next_table(0);
    auto z = y.value().next_table(0);
    if (z.has_value())
    {
      video::vga::text::write("Kernel remapping successfull", video::vga::text::common_attributes::green_on_black);
    }

    // TODO: Seems to work correctly, Level 4 Index 0, Level 3 Index 0, Level 2 Index 0, Level 1 Index 184 = 753667 from
    // mapping vga is still mapped

    // TODO: Map heap virtual pages with active table

    /*
        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);
        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