"""MIT License

Copyright (c) 2019, Swiss Federal Institute of Technology (ETH Zurich), Matthias Meyer


Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE."""

import numpy as np
import pandas as pd
import warnings
import datetime as dt

from .management import DataSource
from ..core import configuration


class DataCollector(DataSource):
    def __init__(self, data_paths=[], granularities=[]):
        """Add and choose data path according to its granularity.
           The data collector returns the data path given an index segment (index_end - index_start).
           The index segment is compared against the given granularities and the mapped data path is
           returned. For example, for a time series where the index is a datetime object, the timedelta
           of (end_time - start_time) is compared against the given list of granularity timedeltas.
        
        Keyword Arguments:
            datapaths {list}        -- a list of data paths, e.g. the leafs of a dask graph (default: {[]})
            granularities {list}    -- a list of sorted granularities (default: {[]})
        """
        super().__init__()

        self.data_paths = data_paths
        self.granularities = granularities

        if len(self.data_paths) != len(self.granularities):
            raise ValueError(
                "Each granularity is supposed to have its corresponding data manager"
            )
        if len(self.granularities) > 1 and not self.is_sorted(self.granularities):
            raise ValueError("Granularities should be sorted")

    def forward(self, data=None, request=None):
        if len(self.data_paths) != len(self.granularities):
            raise ValueError(
                "Each granularity is supposed to have its corresponding data manager"
            )
        if len(self.granularities) > 1 and not self.is_sorted(self.granularities):
            raise ValueError("Granularities should be sorted")

        # TODO: change to generic indices or slices
        granularity = request["end_time"] - request["start_time"]

        data_path = None
        for i in range(len(self.granularities)):
            print(i, granularity, "<", self.granularities[i], self.data_paths[i])
            if granularity < self.granularities[i]:
                data_path = self.data_paths[i]
                break

        if data_path is None:
            raise AttributeError("No data manager can be used for this timeframe")

        return data_path

    def is_sorted(self, l):
        """Check whether a list is sorted
        
        Arguments:
            l {list} -- the list to be determined whether sorted
        
        Returns:
            [bool] -- if the list is sorted, return true
        """
        return all(a <= b for a, b in zip(l, l[1:]))