import typing
from dataclasses import dataclass
from urllib.parse import urlparse

from sqlalchemy.orm import Session
from sqlalchemy.orm import joinedload

from app import activitypub as ap

if typing.TYPE_CHECKING:
    from app.models import Actor as ActorModel


def _handle(raw_actor: ap.RawObject) -> str:
    ap_id = ap.get_id(raw_actor["id"])
    domain = urlparse(ap_id)
    if not domain.hostname:
        raise ValueError(f"Invalid actor ID {ap_id}")

    return f'@{raw_actor["preferredUsername"]}@{domain.hostname}'  # type: ignore


class Actor:
    @property
    def ap_actor(self) -> ap.RawObject:
        raise NotImplementedError()

    @property
    def ap_id(self) -> str:
        return ap.get_id(self.ap_actor["id"])

    @property
    def name(self) -> str | None:
        return self.ap_actor.get("name")

    @property
    def summary(self) -> str | None:
        return self.ap_actor.get("summary")

    @property
    def url(self) -> str | None:
        return self.ap_actor.get("url") or self.ap_actor["id"]

    @property
    def preferred_username(self) -> str:
        return self.ap_actor["preferredUsername"]

    @property
    def handle(self) -> str:
        return _handle(self.ap_actor)

    @property
    def ap_type(self) -> str:
        raise NotImplementedError()

    @property
    def inbox_url(self) -> str:
        return self.ap_actor["inbox"]

    @property
    def shared_inbox_url(self) -> str | None:
        return self.ap_actor.get("endpoints", {}).get("sharedInbox")

    @property
    def icon_url(self) -> str | None:
        return self.ap_actor.get("icon", {}).get("url")

    @property
    def icon_media_type(self) -> str | None:
        return self.ap_actor.get("icon", {}).get("mediaType")

    @property
    def public_key_as_pem(self) -> str:
        return self.ap_actor["publicKey"]["publicKeyPem"]

    @property
    def public_key_id(self) -> str:
        return self.ap_actor["publicKey"]["id"]


class RemoteActor(Actor):
    def __init__(self, ap_actor: ap.RawObject) -> None:
        if (ap_type := ap_actor.get("type")) not in ap.ACTOR_TYPES:
            raise ValueError(f"Unexpected actor type: {ap_type}")

        self._ap_actor = ap_actor
        self._ap_type = ap_type

    @property
    def ap_actor(self) -> ap.RawObject:
        return self._ap_actor

    @property
    def ap_type(self) -> str:
        return self._ap_type

    @property
    def is_from_db(self) -> bool:
        return False


LOCAL_ACTOR = RemoteActor(ap_actor=ap.ME)


def save_actor(db: Session, ap_actor: ap.RawObject) -> "ActorModel":
    from app import models

    if ap_type := ap_actor.get("type") not in ap.ACTOR_TYPES:
        raise ValueError(f"Invalid type {ap_type} for actor {ap_actor}")

    actor = models.Actor(
        ap_id=ap_actor["id"],
        ap_actor=ap_actor,
        ap_type=ap_actor["type"],
        handle=_handle(ap_actor),
    )
    db.add(actor)
    db.commit()
    db.refresh(actor)
    return actor


def fetch_actor(db: Session, actor_id: str) -> "ActorModel":
    from app import models

    existing_actor = (
        db.query(models.Actor).filter(models.Actor.ap_id == actor_id).one_or_none()
    )
    if existing_actor:
        return existing_actor

    ap_actor = ap.get(actor_id)
    return save_actor(db, ap_actor)


@dataclass
class ActorMetadata:
    ap_actor_id: str
    is_following: bool
    is_follower: bool
    is_follow_request_sent: bool
    outbox_follow_ap_id: str | None
    inbox_follow_ap_id: str | None


ActorsMetadata = dict[str, ActorMetadata]


def get_actors_metadata(
    db: Session,
    actors: list["ActorModel"],
) -> ActorsMetadata:
    from app import models

    ap_actor_ids = [actor.ap_id for actor in actors]
    followers = {
        follower.ap_actor_id: follower.inbox_object.ap_id
        for follower in db.query(models.Follower)
        .filter(models.Follower.ap_actor_id.in_(ap_actor_ids))
        .options(joinedload(models.Follower.inbox_object))
        .all()
    }
    following = {
        following.ap_actor_id
        for following in db.query(models.Following.ap_actor_id)
        .filter(models.Following.ap_actor_id.in_(ap_actor_ids))
        .all()
    }
    sent_follow_requests = {
        follow_req.ap_object["object"]: follow_req.ap_id
        for follow_req in db.query(
            models.OutboxObject.ap_object, models.OutboxObject.ap_id
        )
        .filter(
            models.OutboxObject.ap_type == "Follow",
            models.OutboxObject.undone_by_outbox_object_id.is_(None),
        )
        .all()
    }
    idx: ActorsMetadata = {}
    for actor in actors:
        idx[actor.ap_id] = ActorMetadata(
            ap_actor_id=actor.ap_id,
            is_following=actor.ap_id in following,
            is_follower=actor.ap_id in followers,
            is_follow_request_sent=actor.ap_id in sent_follow_requests,
            outbox_follow_ap_id=sent_follow_requests.get(actor.ap_id),
            inbox_follow_ap_id=followers.get(actor.ap_id),
        )
    return idx