"""
This file is designed to specify the appliction of pre/post-processing code. 
    The pre-processing code gets applied after the data has been loaded
    The post-processing code get applied after the data has been generated for instance:
        -approximation code/logic; date shifting; suppression; adding noise
        - 
"""
import numpy as np
from datetime import datetime, timedelta
import time

class Phase:
    def __init__(self,**_args):
        self._df = _args['data']
        self.callback = _args['callback']
    def apply(self,**_args):
        """
            :param  data        data-frame
            :param  _info       arguments needed to be applied
            :param  callback    callback function once done
        """
        raise Exception ("Function needs to be Implemented")
class Pre(Phase):
    pass
class Post(Phase):
    def __init__(self,**_args):
        super().__init__(**_args)
    pass

class Date(Post):
    def __init__(self,**_args):
        super().__init__(**_args)
    def make(self,**_args):
        """
        This function generates a random date given a year and optionally a set of days from the randomly generated date
        :param year     initial value of a year
        :param offset   list of days between initial date    
        """
        if _args['year'] in ['',None,np.nan] :
            return None
        year = int(_args['year'])

        offset = _args['offset'] if 'offset' in _args else 0
        month   = np.random.randint(1,13)
        if month == 2:
            _end = 28 if year % 4 != 0 else 29
        else:
            _end = 31 if month in [1,3,5,7,8,10,12] else 30
        day = np.random.randint(1,_end)

        #-- synthetic date
        _date = datetime(year=year,month=month,day=day,minute=0,hour=0,second=0)
        FORMAT =  '%Y-%m-%d' if 'format' not in _args else _args['format']



        # print ([_name,FORMAT, _date.strftime(FORMAT)])
        r = []
        if offset :
            r = [_date.strftime(FORMAT)]
            for _delta in offset :
                _date = _date + timedelta(_delta)
                r.append(_date.strptime(FORMAT))
            return r
        else:
            return _date.strftime(FORMAT)
        
    def apply(self,**_args):
        """
        
        """
        pass
class Approximate(Post):
    def apply(**_args):
        pass
    def applyWithRange(**_args):