import abc
import typing
import datetime
import copy

import schema
import dateutil.rrule

class Adapter(abc.ABC):
    schema: schema.Schema

    def __init__(self, config, *args, **kwargs):
        _ = args, kwargs
        self.config = config

    @classmethod
    def new(cls, config: dict, *args, **kwargs):
        return cls(cls.schema.validate(config) , *args, **kwargs)

    @abc.abstractmethod
    def login(self) -> bool:
        raise NotImplementedError()

class Source(abc.ABC):

    @abc.abstractmethod
    def get_events(
        self,
        start: datetime.datetime | None=None,
        until: datetime.timedelta | None=None,
        limit=None,
    ) -> typing.Iterable[dict]:
        raise NotImplementedError()

    def get_events_resolved(
        self,
        start: datetime.datetime | None=None,
        until: datetime.timedelta | None=None,
        limit=None,
    ) -> typing.Iterable[dict]:
        until = until if until else datetime.timedelta(days=365)
        now = start if start else datetime.datetime.utcnow().astimezone()
        now_365 = now + until
        for e in self.get_events(
            start=start,
            until=until,
            limit=limit,
        ):
            if 'recurrence' not in e:
                yield e
                continue
            r = e.pop('recurrence')
            r = dateutil.rrule.rrulestr(
                '\n'.join(r),
                unfold=True,
                ignoretz=True,
                dtstart=datetime.datetime.fromisoformat(
                    e['start']['dateTime']
                        if 'dateTime' in e['start'] else
                    e['start']['date']
                ).replace(tzinfo=None)
            )
            for t_ in r.between(now.replace(tzinfo=None), now_365.replace(tzinfo=None)):
                e_ = copy.deepcopy(e)
                if 'dateTime' in e['start']:
                    e_['start']['dateTime'] = datetime.datetime.combine(t_.date(), datetime.datetime.fromisoformat(e['start']['dateTime']).time()).isoformat()
                elif 'date' in e['start']:
                    e_['start']['date'] = datetime.datetime.combine(t_.date(), datetime.time())
                if 'dateTime' in e['end']:
                    e_['end']['dateTime'] = datetime.datetime.combine(t_.date(), datetime.datetime.fromisoformat(e['end']['dateTime']).time()).isoformat()
                elif 'date' in e['end']:
                    e_['end']['date'] = datetime.datetime.combine(t_.date(), datetime.time())
                yield e_
            yield e

class Sink(abc.ABC):

    @abc.abstractmethod
    def post_events(
        self,
        events,
        start: datetime.datetime | None=None,
        until: datetime.timedelta | None=None,
    ) -> bool:
        raise NotImplementedError()