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# File called _pytest for PyCharm compatability

from datetime import timedelta

import numpy as np
import pandas as pd
import pytest

from tests.common import TestData, assert_almost_equal


class TestSeriesMetrics(TestData):
    all_funcs = ["max", "min", "mean", "sum", "nunique", "var", "std", "mad"]
    timestamp_funcs = ["max", "min", "mean", "nunique"]

    def assert_almost_equal_for_agg(self, func, pd_metric, ed_metric):
        if func in ("nunique", "var", "mad"):
            np.testing.assert_almost_equal(pd_metric, ed_metric, decimal=-3)
        else:
            np.testing.assert_almost_equal(pd_metric, ed_metric, decimal=2)

    def test_flights_metrics(self):
        pd_flights = self.pd_flights()["AvgTicketPrice"]
        ed_flights = self.ed_flights()["AvgTicketPrice"]

        for func in self.all_funcs:
            pd_metric = getattr(pd_flights, func)()
            ed_metric = getattr(ed_flights, func)()

            self.assert_almost_equal_for_agg(func, pd_metric, ed_metric)

    def test_flights_timestamp(self):
        pd_flights = self.pd_flights()["timestamp"]
        ed_flights = self.ed_flights()["timestamp"]

        for func in self.timestamp_funcs:
            pd_metric = getattr(pd_flights, func)()
            ed_metric = getattr(ed_flights, func)()

            if func == "nunique":
                print(pd_metric, ed_metric)
                self.assert_almost_equal_for_agg(func, pd_metric, ed_metric)
            elif func == "mean":
                offset = timedelta(seconds=0.001)
                assert (ed_metric - offset) < pd_metric < (ed_metric + offset)
            else:
                assert pd_metric == ed_metric

    def test_ecommerce_selected_non_numeric_source_fields(self):
        # None of these are numeric, will result in NaNs
        column = "category"

        ed_ecommerce = self.ed_ecommerce()[column]

        for func in self.all_funcs:
            if func == "nunique":  # nunique never returns 'NaN'
                continue

            ed_metric = getattr(ed_ecommerce, func)(numeric_only=False)
            print(func, ed_metric)
            assert np.isnan(ed_metric)

    def test_ecommerce_selected_all_numeric_source_fields(self):
        # All of these are numeric
        columns = ["total_quantity", "taxful_total_price", "taxless_total_price"]

        for column in columns:
            pd_ecommerce = self.pd_ecommerce()[column]
            ed_ecommerce = self.ed_ecommerce()[column]

            for func in self.all_funcs:
                pd_metric = getattr(pd_ecommerce, func)()
                ed_metric = getattr(ed_ecommerce, func)(
                    **({"numeric_only": True} if (func != "nunique") else {})
                )
                self.assert_almost_equal_for_agg(func, pd_metric, ed_metric)

    @pytest.mark.parametrize("agg", ["mean", "min", "max"])
    def test_flights_datetime_metrics_agg(self, agg):
        ed_timestamps = self.ed_flights()["timestamp"]
        expected_values = {
            "min": pd.Timestamp("2018-01-01 00:00:00"),
            "mean": pd.Timestamp("2018-01-21 19:20:45.564438232"),
            "max": pd.Timestamp("2018-02-11 23:50:12"),
        }
        ed_metric = getattr(ed_timestamps, agg)()

        assert_almost_equal(ed_metric, expected_values[agg])

    def test_flights_datetime_median_metric(self):
        ed_series = self.ed_flights_small()["timestamp"]

        median = ed_series.median()
        assert isinstance(median, pd.Timestamp)
        assert (
            pd.to_datetime("2018-01-01 10:00:00.000")
            <= median
            <= pd.to_datetime("2018-01-01 12:00:00.000")
        )