#include "x86_64/memory/scoped_mapping.hpp"

#include "kapi/memory.hpp"
#include "kapi/system.hpp"

#include "x86_64/memory/mmu.hpp"
#include "x86_64/memory/paging_root.hpp"

#include <utility>

namespace teachos::memory::x86_64
{

  scoped_mapping::scoped_mapping(scoped_mapping && other)
      : m_address{std::exchange(other.m_address, linear_address{})}
      , m_allocator{std::exchange(other.m_allocator, nullptr)}
      , m_mapped{std::exchange(other.m_mapped, false)}
  {}

  scoped_mapping::scoped_mapping(linear_address address, frame_allocator & allocator)
      : m_address{address}
      , m_allocator{&allocator}
      , m_mapped{false}
  {
    if (paging_root::get().translate(address))
    {
      system::panic("[MEM] Tried to map a page that is already mapped!");
    }
  }

  scoped_mapping::~scoped_mapping()
  {
    if (m_mapped)
    {
      unmap();
      x86_64::tlb_flush(m_address);
    }
  }

  auto scoped_mapping::operator=(scoped_mapping && other) -> scoped_mapping &
  {
    if (&other == this)
    {
      return *this;
    }

    using std::swap;

    swap(m_address, other.m_address);
    swap(m_allocator, other.m_allocator);
    swap(m_mapped, other.m_mapped);

    return *this;
  }

  auto scoped_mapping::map(frame frame, page_table::entry::flags flags) -> std::byte *
  {
    static_cast<void>(frame);
    static_cast<void>(flags);

    m_mapped = true;

    return nullptr;
  }

  auto scoped_mapping::unmap() -> void
  {
    if (!m_mapped)
    {
      system::panic("[MEM] Tried to release an unmapped temporary mapping!");
    }

    // TODO: scan pages
    // TODO: remove mapping
    // TODO: release temporary table frames
    m_mapped = false;
  }

}  // namespace teachos::memory::x86_64