#include "kernel/devices/block_device.hpp"

#include "kapi/devices/device.hpp"
#include "kapi/system.hpp"

#include <kstd/string>

#include <cstddef>

namespace kernel::devices
{
  block_device::block_device(size_t major, size_t minor, kstd::string const & name, size_t block_size)
      : kapi::devices::device(major, minor, name)
      , m_block_size(block_size)
  {
    if (m_block_size == 0)
    {
      kapi::system::panic("[DEVICES] block_device constructed with zero block size.");
    }
  }

  auto block_device::calculate_transfer(size_t block_index) const -> transfer_info
  {
    size_t const offset = block_index * m_block_size;
    size_t const limit = size();

    size_t const available = (offset < limit) ? (limit - offset) : 0;
    size_t const to_transfer = (available < m_block_size) ? available : m_block_size;

    return {offset, to_transfer, m_block_size - to_transfer};
  }

  auto block_device::block_size() const -> size_t
  {
    return m_block_size;
  }

  auto block_device::capacity() const -> size_t
  {
    return size();
  }
}  // namespace kernel::devices