"""WizardKit: ddrescue TUI - State"""
# vim: sts=2 sw=2 ts=2

import atexit
import logging
import pathlib
import plistlib
import re

from wk import exe
from wk.std import PLATFORM
from wk.ui import cli


# STATIC VARIABLES
LOG = logging.getLogger(__name__)


# Functions
def mount_raw_image(path) -> pathlib.Path:
  """Mount raw image using OS specific methods, returns pathlib.Path."""
  loopback_path = None

  if PLATFORM == 'Darwin':
    loopback_path = mount_raw_image_macos(path)
  elif PLATFORM == 'Linux':
    loopback_path = mount_raw_image_linux(path)

  # Check
  if not loopback_path:
    cli.print_error(f'Failed to mount image: {path}')

  # Register unmount atexit
  atexit.register(unmount_loopback_device, loopback_path)

  # Done
  return loopback_path


def mount_raw_image_linux(path) -> pathlib.Path:
  """Mount raw image using losetup, returns pathlib.Path."""
  loopback_path = None

  # Mount using losetup
  cmd = [
    'sudo',
    'losetup',
    '--find',
    '--partscan',
    '--show',
    path,
    ]
  proc = exe.run_program(cmd, check=False)

  # Check result
  if proc.returncode == 0:
    loopback_path = proc.stdout.strip()

  # Done
  return loopback_path


def mount_raw_image_macos(path) -> pathlib.Path:
  """Mount raw image using hdiutil, returns pathlib.Path."""
  loopback_path = None
  plist_data = {}

  # Mount using hdiutil
  # plistdata['system-entities'][{}...]
  cmd = [
    'hdiutil', 'attach',
    '-imagekey', 'diskimage-class=CRawDiskImage',
    '-nomount',
    '-plist',
    '-readonly',
    path,
    ]
  proc = exe.run_program(cmd, check=False, encoding=None, errors=None)

  # Check result
  try:
    plist_data = plistlib.loads(proc.stdout)
  except plistlib.InvalidFileException:
    return None
  for dev in plist_data.get('system-entities', []):
    dev_path = dev.get('dev-entry', '')
    if re.match(r'^/dev/disk\d+$', dev_path):
      loopback_path = dev_path

  # Done
  return loopback_path


def unmount_loopback_device(path) -> None:
  """Unmount loopback device using OS specific methods."""
  cmd = []

  # Build OS specific cmd
  if PLATFORM == 'Darwin':
    cmd = ['hdiutil', 'detach', path]
  elif PLATFORM == 'Linux':
    cmd = ['sudo', 'losetup', '--detach', path]

  # Unmount loopback device
  exe.run_program(cmd, check=False)


if __name__ == '__main__':
  print("This file is not meant to be called directly.")