#!/usr/bin/env python3
# -*- coding: utf-8 -*-
"""
Created on Fri Sep 27 16:20:03 2019

@author: tanya
"""

import pandas as pd
import numpy as np


class CleaningUtils:
    '''
    '''
    def convert_dates(series: pd.Series, formats: (str, list)) -> pd.Series:
        '''
        '''
        formats = list(formats)

        converted = pd.Series([pd.to_datetime(np.nan)]*len(series))

        for formt in formats:
            if formt == "%d%m%Y":
                missing_leading_zero = (series.astype(str).str.len() == 7)

                series = series.astype(str)

                series.loc[missing_leading_zero] = "0" +\
                    series.loc[missing_leading_zero]

            converted_this_format = pd.to_datetime(series,
                                                   format=formt,
                                                   errors="coerce")

            converted.fillna(converted_this_format, inplace=True)

        return converted

    def standarize_writing(self, s: str):
        '''
        '''
        import re

        german_character_mapping = {"ß": "ss",
                                    "ü": "ue",
                                    "Ü": "Ue",
                                    "ä": "ae",
                                    "Ä": "Ae",
                                    "ö": "oe",
                                    "Ö": "Oe"}

        s = s.encode('raw_unicode_escape').decode('raw_unicode_escape')
        for char, correct_char in german_character_mapping.items():
            s = s.replace(char, correct_char)

        s = s.lower()

        s = re.sub('[^0-9a-zA-Z]+', '_', s)

        return s