import datetime as dt
import os
import re
import typing

import mutagen

from symuid import _tag_interface
from symuid._datetime import datetime_utc_now, unix_epoch_time_to_datetime_utc


class PlayCount:

    def __init__(self, player, library_id, register_dt, count):
        self.player = player
        self.library_id = library_id
        assert isinstance(register_dt, dt.datetime), register_dt
        assert register_dt.tzinfo is not None, register_dt
        self.register_dt = register_dt
        assert isinstance(count, int) and count >= 0, count
        self.count = count

    def __eq__(self, other):
        # pylint: disable=unidiomatic-typecheck
        return type(self) == type(other) and vars(self) == vars(other)

    def __hash__(self):
        attrs_sorted = sorted(vars(self).items(), key=lambda p: p[0])
        return hash(tuple(v for k, v in attrs_sorted))

    def __repr__(self):
        return 'PlayCount({})'.format(', '.join(
            '{}={!r}'.format(k, v) for k, v in vars(self).items()
        ))


class Track:

    PATH_DEFAULT_IGNORE_REGEX = r'\.(itdb|itc2|itl|jpg|midi?|plist|xml|zip)$'

    def __init__(self, path):
        self._iface = self._select_tag_interface(path)

    @staticmethod
    def _select_tag_interface(track_path) -> _tag_interface.TagInterface:
        mutagen_file = mutagen.File(track_path)
        if mutagen_file is None:
            raise NotImplementedError(track_path)
        if isinstance(mutagen_file.tags, mutagen.id3.ID3):
            return _tag_interface.ID3(mutagen_file)
        if isinstance(mutagen_file.tags, mutagen.mp4.MP4Tags):
            return _tag_interface.MP4(mutagen_file)
        if isinstance(mutagen_file, (mutagen.oggopus.OggOpus,
                                     mutagen.oggvorbis.OggVorbis)):
            return _tag_interface.Ogg(mutagen_file)
        raise NotImplementedError((track_path, type(mutagen_file)))

    def __eq__(self, other: 'Track') -> bool:
        return self.path == other.path

    def __hash__(self) -> int:
        return hash(self.path)

    @property
    def path(self):
        return self._iface.track_path

    @property
    def comment(self):
        return self._iface.get_comment()

    @comment.setter
    def comment(self, comment):
        self._iface.set_comment(comment)
        self._iface.save()

    def get_uuid(self):
        return self._iface.get_track_uuid()

    def assign_uuid(self, uuid):
        if self.get_uuid():
            raise Exception("{!r} already has an uuid".format(self.path))
        self._iface.set_track_uuid(uuid)
        self._iface.save()

    def _get_play_counts(self, player=None, library_id=None):
        label = 'symuid:pcnt'
        assert library_id is None or player is not None
        if player:
            label += ':' + player
            if library_id:
                label += ':' + library_id
        elif library_id:
            raise Exception((player, library_id))
        for k, count in self._iface.get_free_ints(label):
            player, library_id, register_ts_dec = k.split(':')[2:]
            yield PlayCount(
                player=player,
                library_id=library_id,
                register_dt=unix_epoch_time_to_datetime_utc(
                    int(register_ts_dec)),
                count=count,
            )

    def get_play_counts(self) -> typing.Iterator[PlayCount]:
        return self._get_play_counts()

    def _get_latest_play_counts(self, player=None, library_id=None):
        latest = {}
        for count in self._get_play_counts(player, library_id):
            if not count.player in latest:
                latest[count.player] = {}
            if not count.library_id in latest[count.player] \
                    or latest[count.player][count.library_id].register_dt < count.register_dt:
                latest[count.player][count.library_id] = count
        return [c for p in latest.values() for c in p.values()]

    def get_latest_play_count(self, player, library_id):
        assert player is not None, player
        assert library_id is not None, library_id
        counts = self._get_latest_play_counts(player, library_id)
        if len(counts) == 0:
            return None
        assert len(counts) == 1, counts
        return counts[0]

    def get_play_count_sum(self, player=None, library_id=None):
        return sum(c.count for c in self._get_latest_play_counts(player, library_id))

    def register_play_count(self, play_count, tag_set_cb=None):
        assert isinstance(play_count, PlayCount), play_count
        tag_label = 'symuid:pcnt:{}:{}:{:.0f}'.format(
            play_count.player, play_count.library_id,
            play_count.register_dt.timestamp(),
        )
        current_count = self._iface.get_free_int(tag_label)
        if current_count is None:
            new_tag = self._iface.set_free_int(tag_label, play_count.count)
            self._iface.save()
            if tag_set_cb:
                tag_set_cb(self, new_tag)
        elif current_count != play_count.count:
            raise Exception((current_count, play_count.count))

    def increase_play_count(self, player, library_id, tag_set_cb=None):
        current_pc = self.get_latest_play_count(player, library_id)
        self.register_play_count(
            PlayCount(
                player=player,
                library_id=library_id,
                register_dt=datetime_utc_now(),
                count=current_pc.count + 1 if current_pc else 1,
            ),
            tag_set_cb=tag_set_cb,
        )

    @classmethod
    def walk(cls, root_path, path_ignore_regex, ignored_cb=None, unsupported_cb=None):
        for dirpath, _, filenames in os.walk(root_path):
            for filename in filenames:
                track_path = os.path.join(dirpath, filename)
                if path_ignore_regex.search(track_path):
                    if ignored_cb is not None:
                        ignored_cb(track_path)
                else:
                    try:
                        yield cls(track_path)
                    except NotImplementedError as exc:
                        if unsupported_cb is not None:
                            unsupported_cb(track_path, exc)