import logging
import numbers
import os
import time

logger_name = 'HELPERS'
logger = logging.getLogger(logger_name)


class continues_statistic(dict):
    KEY_SINGLE_VALUE = '_'
    KEY_MEAN_VALUE = 'mean_val'
    KEY_MIN_VALUE = 'min_val'
    KEY_MAX_VALUE = 'max_val'
    KEY_NUM_VALUES = 'num_val'
    """
    Value can be a single single numeric value: continues_statistic(num) or multivalue statistic: continues_statistic(val_a=continues_statistic(num_a), val_b=continues_statistic(num_b)). 
    """
    def __init__(self, *args, **kwargs):
        if len(args) == 1 and isinstance(args[0], numbers.Number):
            dict.__init__(self)
            self[self.KEY_SINGLE_VALUE] = {
                self.KEY_MIN_VALUE: args[0],
                self.KEY_MEAN_VALUE: args[0],
                self.KEY_MAX_VALUE: args[0],
                self.KEY_NUM_VALUES: 1,
            }
        else:
            for key in kwargs:
                if isinstance(kwargs[key], numbers.Number):
                    kwargs[key] = continues_statistic(kwargs[key])
            dict.__init__(self, *args, **kwargs)
            for key in self:
                if type(self[key]) is not continues_statistic:
                    data = continues_statistic()
                    if key == self.KEY_SINGLE_VALUE:
                        data[self.KEY_SINGLE_VALUE] = self[key]
                    else:
                        data[self.KEY_SINGLE_VALUE] = self[key][self.KEY_SINGLE_VALUE]
                    self[key] = data

    @property
    def __multivalue__(self):
        if len(self.keys()) == 0:
            raise AttributeError('No data stored in continues statistic')
        elif len(self.keys()) == 1:
            if list(self.keys())[0] != self.KEY_SINGLE_VALUE:
                raise AttributeError("The single value key needs to be %s." % self.KEY_SINGLE_VALUE)
            return False
        return True

    def __add__(self, other):
        rv = continues_statistic(self)
        if self.__multivalue__:
            if self.__multivalue__ != other.__multivalue__ or self.keys() != other.keys():
                raise AttributeError("Instances are incompatible")
            else:
                for key in rv:
                    rv[key] += other[key]
        else:
            rv[self.KEY_SINGLE_VALUE][self.KEY_MEAN_VALUE] = (self[self.KEY_SINGLE_VALUE][self.KEY_MEAN_VALUE] * self[self.KEY_SINGLE_VALUE][self.KEY_NUM_VALUES] + other[self.KEY_SINGLE_VALUE][self.KEY_MEAN_VALUE] * other[self.KEY_SINGLE_VALUE][self.KEY_NUM_VALUES]) / (self[self.KEY_SINGLE_VALUE][self.KEY_NUM_VALUES] + other[self.KEY_SINGLE_VALUE][self.KEY_NUM_VALUES])
            rv[self.KEY_SINGLE_VALUE][self.KEY_MIN_VALUE] = min(self[self.KEY_SINGLE_VALUE][self.KEY_MIN_VALUE], other[self.KEY_SINGLE_VALUE][self.KEY_MIN_VALUE])
            rv[self.KEY_SINGLE_VALUE][self.KEY_MAX_VALUE] = max(self[self.KEY_SINGLE_VALUE][self.KEY_MAX_VALUE], other[self.KEY_SINGLE_VALUE][self.KEY_MAX_VALUE])
            rv[self.KEY_SINGLE_VALUE][self.KEY_NUM_VALUES] = self[self.KEY_SINGLE_VALUE][self.KEY_NUM_VALUES]+other[self.KEY_SINGLE_VALUE][self.KEY_NUM_VALUES]
        return rv
    
    def __str__(self):
        output_for_value = "mean=%%(%s)s, min=%%(%s)s, max=%%(%s)s, num=%%(%s)s" % (self.KEY_MEAN_VALUE, self.KEY_MIN_VALUE, self.KEY_MAX_VALUE, self.KEY_NUM_VALUES)
        if self.__multivalue__:
            rv = ""
            for key in self:
                rv += key + ': ' + str(self[key]) + "\n"
            return rv
        else:
            return output_for_value % self[self.KEY_SINGLE_VALUE]


class ringbuffer(list):
    def __init__(self, *args, **kwargs):
        self.__max_length__ = kwargs.pop('length')
        list.__init__(self, *args, **kwargs)
        self.__reduce_list__()

    def __reduce_list__(self):
        while len(self) > self.__max_length__:
            self.pop(0)

    def append(self, *args, **kwargs):
        rv = list.append(self, *args, **kwargs)
        self.__reduce_list__()
        return rv


class data_collector(object):
    def __init__(self, bufferlength, current_max_age=300.):
        self.__current_max_age__ = current_max_age
        self.__current_data_rinbuffer__ = ringbuffer(length=3)
        #
        self.__last_add_data__ = 0
        self.__continues_statistic__ = None
        self.__yesterdays_statistic__ = None
        self.__measurement_day__ = None
        #
        self.__ringbuffer__ = ringbuffer(length=bufferlength)

    def __process_continues_statistic__(self, **kwargs):
        # rotate continues_statistic day by day
        today = time.strftime('%Y' + os.path.sep + '%m' + os.path.sep + '%d')
        if self.__measurement_day__ is None:
            self.__measurement_day__ = today
        if self.__measurement_day__ != today:
            self.__yesterdays_statistic__ = self.__continues_statistic__
            self.__continues_statistic__ = None
            self.__measurement_day__ = None
        # Set or update continues statistic
        if self.__continues_statistic__ is None:
            self.__continues_statistic__ = continues_statistic(**kwargs)
        else:
            self.__continues_statistic__ += continues_statistic(**kwargs)


    def add_data(self, **kwargs):
        logger.debug('Got data %s', repr(kwargs))
        self.__last_add_data__ = time.time()
        self.__current_data_rinbuffer__.append(kwargs)
        self.__process_continues_statistic__(**kwargs)
        self.__ringbuffer__.append(kwargs)

    @property
    def current(self):
        if len(self.__current_data_rinbuffer__) == 0:
            logger.info('No data available, yet.')
            return None
        elif  time.time() > self.__last_add_data__ + self.__current_max_age__:
            logger.info('Data max age reached. No current data available.')
            return None
        elif  len(self.__current_data_rinbuffer__) < 3:
            return self.__current_data_rinbuffer__[-1]
        else:
            rv = {}
            for key in self.__current_data_rinbuffer__[0]:
                data = []
                for entry in self.__current_data_rinbuffer__:
                    data.append(entry[key])
                else:
                    data.sort()
                    rv[key] = data[1]
            return rv

    @property
    def todays_statistic(self):
        return self.__continues_statistic__

    @property
    def yesterdays_statistic(self):
        return self.__yesterdays_statistic__

    @property
    def databuffer(self):
        return self.__ringbuffer__[:]