from functools import wraps
from glob import glob
from fnmatch import fnmatchcase
from os.path import dirname, isdir, isfile, realpath


def _with_is_allowed(func):
    @wraps(func)
    def wrapper(self, *args, **kwargs):
        if self._is_allowed(args[0]): # pylint: disable=protected-access
            return func(self, *args, **kwargs)
        raise ValueError('Forbidden path.')
    return wrapper


class FileManager: # pylint: disable=too-many-instance-attributes
    def __init__(self, patterns):
        self.patterns = patterns

    @property
    def files(self):
        return list(set(
            path
            for pattern in self.patterns
            for path in glob(pattern, recursive=True)
            if isfile(path) and self._is_allowed(path)
        ))

    @property
    def parents(self):
        return list(set(
            self._find_directory(pattern)
            for pattern in self.patterns
        ))

    @staticmethod
    def _find_directory(pattern):
        while pattern and not isdir(pattern):
            pattern = dirname(pattern)
        return pattern

    def _is_allowed(self, filepath):
        return any(
            fnmatchcase(realpath(filepath), pattern)
            for pattern in self.patterns
        )

    @_with_is_allowed
    def read_file(self, filepath): # pylint: disable=no-self-use
        with open(filepath, 'rb', buffering=0) as ifile:
            return ifile.read().decode(errors='surrogateescape')

    @_with_is_allowed
    def write_file(self, filepath, contents): # pylint: disable=no-self-use
        with open(filepath, 'wb', buffering=0) as ofile:
            ofile.write(contents.encode())