import re
from django.core import validators
from django.core.exceptions import ValidationError
from django.utils.deconstruct import deconstructible
from django.db import models
from django.contrib.auth.models import AbstractUser
from django.utils import timezone
from django.core.serializers.json import DjangoJSONEncoder
from django.utils.translation import gettext_lazy as _
from common.utils import GenerateDateUUIDMediaFilePath
from django.conf import settings
from management.models import Announcement
from mastodon.api import *
from django.urls import reverse
from django.db.models import Q
from django.templatetags.static import static
import hashlib


RESERVED_USERNAMES = [
    "connect",
    "oauth2_login",
    "__",
    "admin",
    "api",
    "me",
]


@deconstructible
class UsernameValidator(validators.RegexValidator):
    regex = r"^[a-zA-Z0-9_]{2,30}$"
    message = _(
        "Enter a valid username. This value may contain only unaccented lowercase a-z "
        "and uppercase A-Z letters, numbers, and _ characters."
    )
    flags = re.ASCII

    def __call__(self, value):
        if value and value.lower() in RESERVED_USERNAMES:
            raise ValidationError(self.message, code=self.code)
        return super().__call__(value)


def report_image_path(instance, filename):
    return GenerateDateUUIDMediaFilePath(
        instance, filename, settings.REPORT_MEDIA_PATH_ROOT
    )


class User(AbstractUser):
    username_validator = UsernameValidator()
    username = models.CharField(
        _("username"),
        max_length=100,
        unique=True,
        null=True,  # allow null for newly registered users who has not set a user name
        help_text=_("Required. 50 characters or fewer. Letters, digits and _ only."),
        validators=[username_validator],
        error_messages={
            "unique": _("A user with that username already exists."),
        },
    )
    email = models.EmailField(_("email address"), unique=True, default=None, null=True)
    pending_email = models.EmailField(
        _("email address pending verification"), default=None, null=True
    )
    following = models.JSONField(default=list)
    mastodon_id = models.CharField(max_length=100, default=None, null=True)
    mastodon_username = models.CharField(max_length=100, default=None, null=True)
    mastodon_site = models.CharField(max_length=100, default=None, null=True)
    mastodon_token = models.CharField(max_length=2048, default="")
    mastodon_refresh_token = models.CharField(max_length=2048, default="")
    mastodon_locked = models.BooleanField(default=False)
    mastodon_followers = models.JSONField(default=list)
    mastodon_following = models.JSONField(default=list)
    mastodon_mutes = models.JSONField(default=list)
    mastodon_blocks = models.JSONField(default=list)
    mastodon_domain_blocks = models.JSONField(default=list)
    mastodon_account = models.JSONField(default=dict)
    mastodon_last_refresh = models.DateTimeField(default=timezone.now)
    # store the latest read announcement id,
    # every time user read the announcement update this field
    read_announcement_index = models.PositiveIntegerField(default=0)

    class Meta:
        constraints = [
            models.UniqueConstraint(
                fields=["mastodon_username", "mastodon_site"],
                name="unique_mastodon_username",
            ),
            models.UniqueConstraint(
                fields=["mastodon_id", "mastodon_site"],
                name="unique_mastodon_id",
            ),
            models.CheckConstraint(
                check=(
                    Q(is_active=False)
                    | Q(mastodon_username__isnull=False)
                    | Q(email__isnull=False)
                ),
                name="at_least_one_login_method",
            ),
        ]

    # def save(self, *args, **kwargs):
    #     """ Automatically populate password field with settings.DEFAULT_PASSWORD before saving."""
    #     self.set_password(settings.DEFAULT_PASSWORD)
    #     return super().save(*args, **kwargs)

    @property
    def mastodon_acct(self):
        return (
            f"{self.mastodon_username}@{self.mastodon_site}"
            if self.mastodon_username
            else ""
        )

    @property
    def display_name(self):
        return (
            self.mastodon_account.get("display_name")
            if self.mastodon_account
            else (self.username or self.mastodon_acct or "")
        )

    @property
    def avatar(self):
        if self.mastodon_account:
            return self.mastodon_account.get("avatar") or static(
                "static/img/avatar.svg"
            )
        if self.email:
            return (
                "https://www.gravatar.com/avatar/"
                + hashlib.md5(self.email.lower().encode()).hexdigest()
            )
        return static("static/img/avatar.svg")

    @property
    def handler(self):
        return self.mastodon_acct or self.username or f"~{self.pk}"

    @property
    def url(self):
        return reverse("journal:user_profile", args=[self.handler])

    def __str__(self):
        return f'{self.pk}:{self.username or ""}:{self.mastodon_acct}'

    def get_preference(self):
        pref = Preference.objects.filter(user=self).first()  # self.preference
        if not pref:
            pref = Preference.objects.create(user=self)
        return pref

    def clear(self):
        if self.mastodon_site == "removed" and not self.is_active:
            return
        self.first_name = self.mastodon_acct or ""
        self.last_name = self.email or ""
        self.is_active = False
        self.email = None
        # self.username = "~removed~" + str(self.pk)
        # to get ready for federation, username has to be reserved
        self.mastodon_username = None
        self.mastodon_id = None
        self.mastodon_site = "removed"
        self.mastodon_token = ""
        self.mastodon_locked = False
        self.mastodon_followers = []
        self.mastodon_following = []
        self.mastodon_mutes = []
        self.mastodon_blocks = []
        self.mastodon_domain_blocks = []
        self.mastodon_account = {}

    def refresh_mastodon_data(self):
        """Try refresh account data from mastodon server, return true if refreshed successfully, note it will not save to db"""
        self.mastodon_last_refresh = timezone.now()
        code, mastodon_account = verify_account(self.mastodon_site, self.mastodon_token)
        if code == 401 and self.mastodon_refresh_token:
            self.mastodon_token = refresh_access_token(
                self.mastodon_site, self.mastodon_refresh_token
            )
            if self.mastodon_token:
                code, mastodon_account = verify_account(
                    self.mastodon_site, self.mastodon_token
                )
        updated = False
        if mastodon_account:
            self.mastodon_account = mastodon_account
            self.mastodon_locked = mastodon_account["locked"]
            if self.mastodon_username != mastodon_account["username"]:
                logger.warn(
                    f"username changed from {self} to {mastodon_account['username']}"
                )
                self.mastodon_username = mastodon_account["username"]
            # self.mastodon_token = token
            # user.mastodon_id  = mastodon_account['id']
            self.mastodon_followers = get_related_acct_list(
                self.mastodon_site,
                self.mastodon_token,
                f"/api/v1/accounts/{self.mastodon_id}/followers",
            )
            self.mastodon_following = get_related_acct_list(
                self.mastodon_site,
                self.mastodon_token,
                f"/api/v1/accounts/{self.mastodon_id}/following",
            )
            self.mastodon_mutes = get_related_acct_list(
                self.mastodon_site, self.mastodon_token, "/api/v1/mutes"
            )
            self.mastodon_blocks = get_related_acct_list(
                self.mastodon_site, self.mastodon_token, "/api/v1/blocks"
            )
            self.mastodon_domain_blocks = get_related_acct_list(
                self.mastodon_site, self.mastodon_token, "/api/v1/domain_blocks"
            )
            self.following = self.get_following_ids()
            updated = True
        elif code == 401:
            print(f"401 {self}")
            self.mastodon_token = ""
        return updated

    def get_following_ids(self):
        fl = []
        for m in self.mastodon_following:
            target = User.get(m)
            if target and (
                (not target.mastodon_locked)
                or self.mastodon_acct in target.mastodon_followers
            ):
                fl.append(target.pk)
        return fl

    def is_blocking(self, target):
        return (
            (
                target.mastodon_acct in self.mastodon_blocks
                or target.mastodon_site in self.mastodon_domain_blocks
            )
            if target.is_authenticated
            else self.preference.no_anonymous_view  # type: ignore
        )

    def is_blocked_by(self, target):
        return target.is_authenticated and target.is_blocking(self)

    def is_muting(self, target):
        return target.mastodon_acct in self.mastodon_mutes

    def is_following(self, target):
        return (
            self.mastodon_acct in target.mastodon_followers
            if target.mastodon_locked
            else self.mastodon_acct in target.mastodon_followers
            or target.mastodon_acct in self.mastodon_following
        )

    def is_followed_by(self, target):
        return target.is_following(self)

    def get_mark_for_item(self, item):
        params = {item.__class__.__name__.lower() + "_id": item.id, "owner": self}
        mark = item.mark_class.objects.filter(**params).first()
        return mark

    def get_max_visibility(self, viewer):
        if not viewer.is_authenticated:
            return 0
        elif viewer == self:
            return 2
        elif viewer.is_blocked_by(self):
            return -1
        elif viewer.is_following(self):
            return 1
        else:
            return 0

    @property
    def unread_announcements(self):
        unread_announcements = Announcement.objects.filter(
            pk__gt=self.read_announcement_index
        ).order_by("-pk")
        return unread_announcements

    @classmethod
    def get(cls, name):
        if isinstance(name, str):
            sp = name.split("@")
            if name.startswith("~"):
                try:
                    query_kwargs = {"pk": int(name[1:])}
                except:
                    return None
            elif len(sp) == 1:
                query_kwargs = {"username": name}
            elif len(sp) == 2:
                query_kwargs = {"mastodon_username": sp[0], "mastodon_site": sp[1]}
            else:
                return None
        elif isinstance(name, int):
            query_kwargs = {"pk": name}
        else:
            return None
        return User.objects.filter(**query_kwargs).first()


class Preference(models.Model):
    user = models.OneToOneField(User, models.CASCADE, primary_key=True)
    profile_layout = models.JSONField(
        blank=True,
        default=list,
    )
    discover_layout = models.JSONField(
        blank=True,
        default=list,
    )
    export_status = models.JSONField(
        blank=True, null=True, encoder=DjangoJSONEncoder, default=dict
    )
    import_status = models.JSONField(
        blank=True, null=True, encoder=DjangoJSONEncoder, default=dict
    )
    default_no_share = models.BooleanField(default=False)
    default_visibility = models.PositiveSmallIntegerField(default=0)
    classic_homepage = models.PositiveSmallIntegerField(null=False, default=0)
    mastodon_publish_public = models.BooleanField(null=False, default=False)
    mastodon_append_tag = models.CharField(max_length=2048, default="")
    show_last_edit = models.PositiveSmallIntegerField(default=0)
    no_anonymous_view = models.PositiveSmallIntegerField(default=0)

    def __str__(self):
        return str(self.user)


class Report(models.Model):
    submit_user = models.ForeignKey(
        User, on_delete=models.SET_NULL, related_name="sumbitted_reports", null=True
    )
    reported_user = models.ForeignKey(
        User, on_delete=models.SET_NULL, related_name="accused_reports", null=True
    )
    image = models.ImageField(
        upload_to=report_image_path,
        blank=True,
        default="",
    )
    is_read = models.BooleanField(default=False)
    submitted_time = models.DateTimeField(auto_now_add=True)
    message = models.CharField(max_length=1000)