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# regarding copyright ownership.  The SFC licenses this file
# to you under the Apache License, Version 2.0 (the
# "License"); you may not use this file except in compliance
# with the License.  You may obtain a copy of the License at
#
#   http://www.apache.org/licenses/LICENSE-2.0
#
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# software distributed under the License is distributed on an
# "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
# KIND, either express or implied.  See the License for the
# specific language governing permissions and limitations
# under the License.

from abc import ABCMeta, abstractmethod
import os
from typing import Optional
from selenium.types import AnyKey
from selenium.webdriver.common.utils import keys_to_typing


class FileDetector(metaclass=ABCMeta):
    """
    Used for identifying whether a sequence of chars represents the path to a
    file.
    """

    @abstractmethod
    def is_local_file(self, *keys: AnyKey) -> Optional[str]:
        raise NotImplementedError


class UselessFileDetector(FileDetector):
    """
    A file detector that never finds anything.
    """

    def is_local_file(self, *keys: AnyKey) -> Optional[str]:
        return None


class LocalFileDetector(FileDetector):
    """
    Detects files on the local disk.
    """

    def is_local_file(self, *keys: AnyKey) -> Optional[str]:
        file_path = ''.join(keys_to_typing(keys))

        if not file_path:
            return None

        try:
            if os.path.isfile(file_path):
                return file_path
        except Exception:
            pass
        return None