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# or more contributor license agreements.  See the NOTICE file
# distributed with this work for additional information
# 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
#
# Unless required by applicable law or agreed to in writing,
# 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.

import abc
import os
from selenium.webdriver.common.keys import Keys


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

    @abc.abstractmethod
    def is_local_file(self, *keys):
        return


class UselessFileDetector(FileDetector):
    """
    A file detector that never finds anything.
    """
    def is_local_file(self, *keys):
        return None


class LocalFileDetector(FileDetector):
    """
    Detects files on the local disk.
    """
    def is_local_file(self, *keys):
        file_path = ''
        typing = []
        for val in keys:
            if isinstance(val, Keys):
                typing.append(val)
            elif isinstance(val, int):
                val = val.__str__()
                for i in range(len(val)):
                    typing.append(val[i])
            else:
                for i in range(len(val)):
                    typing.append(val[i])
        file_path = ''.join(typing)

        if file_path is '':
            return None

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