import re
import uuid

from django.conf import settings
from django.db import connection, models
from django.db.models import Avg, Count, Q
from django.utils import timezone
from django.utils.baseconv import base62
from django.utils.translation import gettext_lazy as _
from polymorphic.models import PolymorphicModel

from catalog.common.models import AvailableItemCategory, Item, ItemCategory
from catalog.models import *
from takahe.utils import Takahe
from users.models import APIdentity, User

from .mixins import UserOwnedObjectMixin

_logger = logging.getLogger(__name__)


class VisibilityType(models.IntegerChoices):
    Public = 0, _("公开")
    Follower_Only = 1, _("仅关注者")
    Private = 2, _("仅自己")


def q_owned_piece_visible_to_user(viewing_user: User, owner: APIdentity):
    if (
        not viewing_user
        or not viewing_user.is_authenticated
        or not viewing_user.identity
    ):
        return Q(visibility=0)
    viewer = viewing_user.identity
    if viewer == owner:
        return Q()
    # elif viewer.is_blocked_by(owner):
    #     return Q(pk__in=[])
    elif viewer.is_following(owner):
        return Q(owner=owner, visibility__in=[0, 1])
    else:
        return Q(owner=owner, visibility=0)


def max_visiblity_to_user(viewing_user: User, owner: APIdentity):
    if (
        not viewing_user
        or not viewing_user.is_authenticated
        or not viewing_user.identity
    ):
        return 0
    viewer = viewing_user.identity
    if viewer == owner:
        return 2
    elif viewer.is_following(owner):
        return 1
    else:
        return 0


def q_piece_visible_to_user(user: User):
    if not user or not user.is_authenticated or not user.identity:
        return Q(visibility=0)
    return (
        Q(visibility=0)
        | Q(owner_id__in=user.identity.following, visibility=1)
        | Q(owner_id=user.identity.pk)
    ) & ~Q(owner_id__in=user.identity.ignoring)


def q_piece_in_home_feed_of_user(user: User):
    return Q(owner_id__in=user.identity.following, visibility__lt=2) | Q(
        owner_id=user.identity.pk
    )


def q_item_in_category(item_category: ItemCategory | AvailableItemCategory):
    classes = item_categories()[item_category]
    # q = Q(item__instance_of=classes[0])
    # for cls in classes[1:]:
    #     q = q | Q(instance_of=cls)
    # return q
    ct = item_content_types()
    contenttype_ids = [ct[cls] for cls in classes]
    return Q(item__polymorphic_ctype__in=contenttype_ids)


# class ImportStatus(Enum):
#     QUEUED = 0
#     PROCESSING = 1
#     FINISHED = 2


# class ImportSession(models.Model):
#     owner = models.ForeignKey(APIdentity, on_delete=models.CASCADE)
#     status = models.PositiveSmallIntegerField(default=ImportStatus.QUEUED)
#     importer = models.CharField(max_length=50)
#     file = models.CharField()
#     default_visibility = models.PositiveSmallIntegerField()
#     total = models.PositiveIntegerField()
#     processed = models.PositiveIntegerField()
#     skipped = models.PositiveIntegerField()
#     imported = models.PositiveIntegerField()
#     failed = models.PositiveIntegerField()
#     logs = models.JSONField(default=list)
#     created_time = models.DateTimeField(auto_now_add=True)
#     edited_time = models.DateTimeField(auto_now=True)

#     class Meta:
#         indexes = [
#             models.Index(fields=["owner", "importer", "created_time"]),
#         ]


class Piece(PolymorphicModel, UserOwnedObjectMixin):
    url_path = "p"  # subclass must specify this
    uid = models.UUIDField(default=uuid.uuid4, editable=False, db_index=True)
    local = models.BooleanField(default=True)
    post_id = models.BigIntegerField(null=True, default=None)

    class Meta:
        indexes = [
            models.Index(fields=["post_id"]),
        ]

    @property
    def uuid(self):
        return base62.encode(self.uid.int)

    @property
    def url(self):
        return f"/{self.url_path}/{self.uuid}" if self.url_path else None

    @property
    def absolute_url(self):
        return (settings.SITE_INFO["site_url"] + self.url) if self.url_path else None

    @property
    def api_url(self):
        return f"/api/{self.url}" if self.url_path else None

    @property
    def shared_link(self):
        return Takahe.get_post_url(self.post_id) if self.post_id else None

    @property
    def like_count(self):
        return (
            Takahe.get_post_stats(self.post_id).get("likes", 0) if self.post_id else 0
        )

    def is_liked_by(self, user):
        return self.post_id and Takahe.post_liked_by(self.post_id, user)

    @classmethod
    def get_by_url(cls, url_or_b62):
        b62 = url_or_b62.strip().split("/")[-1]
        if len(b62) not in [21, 22]:
            r = re.search(r"[A-Za-z0-9]{21,22}", url_or_b62)
            if r:
                b62 = r[0]
        try:
            obj = cls.objects.get(uid=uuid.UUID(int=base62.decode(b62)))
        except:
            obj = None
        return obj

    @classmethod
    def update_by_ap_object(cls, owner, item, obj, post_id, visibility):
        raise NotImplemented

    @property
    def ap_object(self):
        raise NotImplemented


class Content(Piece):
    owner = models.ForeignKey(APIdentity, on_delete=models.PROTECT)
    visibility = models.PositiveSmallIntegerField(
        default=0
    )  # 0: Public / 1: Follower only / 2: Self only
    created_time = models.DateTimeField(default=timezone.now)
    edited_time = models.DateTimeField(
        default=timezone.now
    )  # auto_now=True   FIXME revert this after migration
    metadata = models.JSONField(default=dict)
    item = models.ForeignKey(Item, on_delete=models.PROTECT)
    remote_id = models.CharField(max_length=200, null=True, default=None)

    def __str__(self):
        return f"{self.uuid}@{self.item}"

    class Meta:
        abstract = True