import re

from django.db import models
from django.template.defaultfilters import slugify
from django.utils.translation import gettext_lazy as _

import requests

from aleksis.core.mixins import ExtensibleModel, ExtensiblePolymorphicModel
from aleksis.core.models import Group, Person


class MatrixProfile(ExtensibleModel):
    """Model for a Matrix profile."""

    matrix_id = models.CharField(max_length=255, verbose_name=_("Matrix ID"), unique=True)
    person = models.OneToOneField(
        Person,
        on_delete=models.CASCADE,
        verbose_name=_("Person"),
        null=True,
        blank=True,
        related_name="matrix_profile",
    )

    class Meta:
        verbose_name = _("Matrix profile")
        verbose_name_plural = _("Matrix profiles")


class MatrixRoom(ExtensiblePolymorphicModel):
    """Model for a Matrix room."""

    room_id = models.CharField(max_length=255, verbose_name=_("Room ID"), unique=True)
    alias = models.CharField(max_length=255, verbose_name=_("Alias"), unique=True, blank=True)
    group = models.ForeignKey(
        Group,
        on_delete=models.CASCADE,
        verbose_name=_("Group"),
        null=True,
        blank=True,
        related_name="matrix_spaces",
    )

    @classmethod
    def from_group(self, group: Group):
        """Create a Matrix room from a group."""
        from .matrix import MatrixException, build_url, get_headers

        try:
            room = MatrixRoom.objects.get(group=group)
        except MatrixRoom.DoesNotExist:
            room = MatrixRoom(group=group)

        if room.room_id:
            # Existing room, check if still accessible
            r = requests.get(
                build_url(f"directory/list/room/{room.room_id}"), headers=get_headers()
            )
            if not r.status_code == requests.codes.ok:
                raise MatrixException()
        else:
            # Room does not exist, create it
            alias = slugify(group.short_name or group.name)
            r = self._create_group(group.name, alias)
            while r.json().get("errcode") == "M_ROOM_IN_USE":
                match = re.match(r"^(.*)-(\d+)$", alias)
                if match:
                    # Counter found, increase
                    prefix = match.group(1)
                    counter = int(match.group(2)) + 1
                    alias = f"{prefix}-{counter}"
                else:
                    # Counter not found, add one
                    alias = f"{alias}-2"
                r = self._create_group(group.name, alias)

            if r.status_code == requests.codes.ok:
                room.room_id = r.json()["room_id"]
                room.alias = r.json()["room_alias"]
                room.save()
            else:
                raise MatrixException(r.text)
        return room

    @classmethod
    def _create_group(self, name, alias):
        from .matrix import build_url, get_headers

        body = {"preset": "private_chat", "name": name, "room_alias_name": alias}
        r = requests.post(build_url("createRoom"), headers=get_headers(), json=body)

        return r

    class Meta:
        verbose_name = _("Matrix room")
        verbose_name_plural = _("Matrix rooms")


class MatrixSpace(MatrixRoom):
    children = models.ManyToManyField(
        to=MatrixRoom, verbose_name=_("Child rooms/spaces"), blank=True, related_name="parents"
    )

    class Meta:
        verbose_name = _("Matrix space")
        verbose_name_plural = _("Matrix spaces")