import operator

from functools import reduce

from ..time import TimeSpan

from .metrics import Metrics

class Aggregation:

def __init__(self, timespan: TimeSpan, metrics: Metrics):

self.timespan = timespan

self.metrics = metrics

@classmethod

def from_sample(cls, sample):

timestamp, value = sample

timespan = TimeSpan(timestamp, timestamp)

metrics = Metrics.from_value(value)

return cls(timespan, metrics)

@staticmethod

def from_samples(samples):

""" Take a bunch of samples, and convert into a single metric. """

assert samples

return reduce(operator.add, map(Aggregation.from_sample, samples))

@classmethod

def from_aggregations(cls, aggregations):

assert aggregations

metrics = []

timespans = []

for aggregation in aggregations:

assert isinstance(aggregation, Aggregation)

metrics.append(aggregation.metrics)

timespans.append(aggregation.timespan)

timespan = TimeSpan.from_timespans(timespans)

metrics = Metrics.from_metrics(metrics)

return cls(timespan, metrics)

def __add__(self, other):

if isinstance(other, Aggregation):

metrics = self.metrics + other.metrics

timespan = TimeSpan.from_timespans([self.timespan, other.timespan])

return Aggregation(timespan, metrics)

else: # pragma: no cover

return NotImplemented