#!/usr/bin/env python3
from typing import Any
import uuid

from sqlalchemy.orm import session

from app import models
from app import ldsig
from app.database import AsyncSession
from app.models import InboxObject, OutboxObject, now
from app.activitypub import ME
from app.activitypub import handle_visibility
from app.config import MANUALLY_APPROVES_FOLLOWERS
from app.config import BASE_URL, ID
from app.models import Actor
from app.actor import fetch_actor
from app.httpsig import k

import app.activitypub as ap

from urllib.parse import urlparse
from sqlalchemy import select
from sqlalchemy import delete
from sqlalchemy.orm import joinedload
from sqlalchemy.exc import  IntegrityError
from loguru import logger
from uuid import uuid4
from datetime import datetime



def allocate_outbox_id() -> str:
    return str(uuid.uuid4())


def build_object_id(id) -> str:
    return f"{BASE_URL}/tail/{id}"


async def get_outbox_object(
        db_session: AsyncSession,
        ap_id: str,
) -> OutboxObject | None :
    return (
        (
            await db_session.execute(
                select(OutboxObject)
                .where(OutboxObject.ap_id == ap_id)
                .options(
                    joinedload(OutboxObject.relates_to_inbox_object).options(
                        joinedload(InboxObject.actor),
                    ),
                )
            )
        )
        .unique()
        .scalar_one_or_none()
    )


async def save_incoming(
        db_session: AsyncSession,
        payload: dict,
) -> models.IncomingActivity | None:
    ap_id: str
    if "@context" not in payload:
        logger.warning(f"invalid object: {payload}")
        return None

    if "id" in payload:
        ap_id = payload["id"]
    else:
        ap_id = str(uuid4())

    incoming_activity = models.IncomingActivity(
        ap_id=ap_id,
        ap_object=payload,
    )

    if await process_incoming(db_session, payload):
        await db_session.commit()
        await db_session.flush()
        return incoming_activity

    db_session.add(incoming_activity)
    await db_session.commit()
    await db_session.refresh(incoming_activity)
    return incoming_activity


async def process_incoming(
        db_session: AsyncSession,
        ap_object: dict,
) -> bool:
    actor = await fetch_actor(db_session, ap_object["actor"])

    relates_to_inbox_object = None
    relates_to_outbox_object = None

    if ap_object["object"].startswith(BASE_URL):
        relates_to_outbox_object = await get_outbox_object(
            db_session,
            ap_object["object"],
        )

    def build_object(
            object,
            relates_to_inbox_object_id = None,
            relates_to_outbox_object_id = None,
    ) -> InboxObject:
        inbox_object = models.InboxObject(
            actor_id=actor.id,
            server=urlparse(object["id"]).hostname,
            is_hidden_from_stream=True,
            ap_actor_id=actor.ap_id,
            ap_type=object["type"],
            ap_id=object["id"],
            ap_published_at=now(),
            ap_object=object,
            visibility=handle_visibility(object),
            activity_object_ap_id=object["actor"],
            relates_to_inbox_object_id=relates_to_inbox_object_id,
            relates_to_outbox_object_id=relates_to_outbox_object_id,
        )
        return inbox_object

    if "Follow" == ap_object["type"]:
        inbox_object = build_object(ap_object)
        db_session.add(inbox_object)
        await db_session.flush()
        await db_session.refresh(inbox_object)

        if await _handle_follow(db_session, actor, inbox_object):
            return True
        return False
    elif "Undo" == ap_object["type"]:
        #inbox_object = build_object(ap_object)
        #db_session.add(inbox_object)
        if await _handle_undo(db_session, ap_object):
            return True
    elif ap_object["type"] in ["Accept", "Rejact"]:
        relate_following_object = (await db_session.execute(
            select(models.OutboxObject)
            .where(models.OutboxObject.ap_id == ap_object["object"])
            .options(
               joinedload(models.OutboxObject.relates_to_inbox_object).options(
                   joinedload(models.InboxObject.actor)
               )
            )
        )
        ).unique().scalar_one_or_none()

        if "Accept" == ap_object["type"]:
            inbox_object = build_object(ap_object)
            db_session.add(inbox_object)
            await db_session.flush()
            await db_session.refresh(inbox_object)

            following = models.Following(
                actor_id=relate_following_object.relates_to_actor.id,
                outbox_object_id=relate_following_object.id,
                ap_actor_id=ap_object["actor"],
            )

            db_session.add(following)
            await db_session.flush()
            await db_session.refresh(following)
            return True
    elif "Announce" == ap_object["type"]:
        inbox_object = build_object(
            ap_object,
            relates_to_inbox_object_id=relates_to_inbox_object,
            relates_to_outbox_object_id=relates_to_outbox_object,
        )
        db_session.add(inbox_object)
        await db_session.flush()
        await db_session.refresh(inbox_object)

        if await _handle_announce(
            db_session,
            inbox_object,
            relates_to_outbox_object=relates_to_outbox_object,
            relates_to_inbox_object=relates_to_inbox_object,
        ):
            return True


    return False


async def _handle_follow(
        db_session : AsyncSession,
        actor : Actor,
        inbox_object : InboxObject,
) -> bool:
    if ME["id"] != inbox_object.ap_object["object"]: #type: ignore
        # await db_session.delete(ap_object)
        logger.warning("no match follow object!" + inbox_object.ap_object["id"]) #type: ignore
        return False

    if MANUALLY_APPROVES_FOLLOWERS:
        return False

    await _send_accept(db_session, actor, inbox_object)
    return True


async def _send_accept(
        db_session: AsyncSession,
        actor : Actor,
        inbox_object : InboxObject,
) -> None :
    follower = models.Follower(
        actor_id=inbox_object.actor_id,
        inbox_object_id=inbox_object.id,
        ap_actor_id=inbox_object.ap_object["actor"], #type: ignore
    )

    try:
        db_session.add(follower)
        await db_session.flush()
    except IntegrityError:
        await db_session.rollback()
        logger.warning("existing follower in db!")

    try:
        reply_id = allocate_outbox_id()

        url = actor.inbox_url # type: ignore
        out = {
            "@context": ap.AS_CTX,
            "id": build_object_id(reply_id),
            "type": "Accept",
            "actor": ME["id"],
            "object": inbox_object.ap_object["id"], #type: ignore
        }
        #TODO outcoming
        await ap.post(url, out) # type: ignore
    except Exception as e:
        logger.error(e)


async def _handle_undo(
        db_session : AsyncSession,
        inbox_object : dict
) -> bool:
    if inbox_object["object"]["object"] != ME["id"]:
        logger.warning("Wrong undo object! "
                       + inbox_object["object"]["actor"])
        return False

    if "Follow" == inbox_object["object"]["type"]:
        relate_object = (await db_session.execute(
            select(models.InboxObject)
            .where(models.InboxObject.ap_id == inbox_object["object"]["id"])
            .options(
                joinedload(models.InboxObject.actor),
                joinedload(models.InboxObject.relates_to_inbox_object),
                joinedload(models.InboxObject.relates_to_outbox_object),
                )
            )
        ).scalar_one_or_none()  # type: ignore

        if relate_object:
            relate_object.undo_id=inbox_object["object"]["id"]
            relate_object.is_deleted=True

        await db_session.execute(
            delete(models.Follower).where(
                models.Follower.ap_actor_id == inbox_object["actor"]
            )
        )
        logger.info("undo follow " + inbox_object["actor"])
        return True

    return False


async def send_follow(
        db_session : AsyncSession,
        acct : str
):
    await _send_follow(db_session, acct)
    await db_session.commit()
    await db_session.flush()


async def _handle_announce(
        db_session: AsyncSession,
        inbox_object: InboxObject,
        relates_to_outbox_object: models.OutboxObject | None,
        relates_to_inbox_object: models.InboxObject | None,
) -> bool :
    if relates_to_outbox_object:
        relates_to_outbox_object.announces_count = (
            models.OutboxObject.announces_count + 1
        )
        logger.info(f"announces +1 {relates_to_outbox_object.ap_id}")
        return True
    else:
        return False


async def _send_follow(
        db_session : AsyncSession,
        actor_url : str,
):
    actor = await fetch_actor(db_session, actor_url)

    follow_id = build_object_id(allocate_outbox_id())
    out = {
        "@context": ap.AS_CTX,
        "id": follow_id,
        "type": "Follow",
        "actor": ME["id"],
        "object": actor.ap_id,
    }

    await save_to_outbox(
        db_session,
        follow_id,
        out,
        relates_to_actor_id=actor.id, # type: ignore
    )

    await ap.post(
        actor.inbox_url,
        out,
    )


async def _send_create(
        db_session: AsyncSession,
        ap_type: str,
        content: str,
        visibility: ap.VisibilityEnum,
        published: str | None = None,
) -> bool:
    object_id = allocate_outbox_id()
    if not published:
        published = now().replace(microsecond=0).isoformat().replace("+00:00", "Z")

    to = []
    cc = []

    if visibility == ap.VisibilityEnum.PUBLIC:
        to = [ap.AS_PUBLIC]
        cc = [f"{BASE_URL}/followers"]
    else:
        raise ValueError(f"Unsupport visibility {visibility}")

    ap_object = {
        "@context": ap.AS_EXTENDED_CTX,
        "type": ap_type,
        "id": build_object_id(object_id),
        "attributedTo": ID,
        "content": content,
        "to": to,
        "cc": cc,
        "published": published,
        # "context": context,
        # "conversation": context,
        "url": build_object_id(object_id),
        "tag": [],
        "summary": None,
        "inReplyTo": None,
        "sensitive": False,
        "attachment": [],
    }

    outbox_object = await save_to_outbox(
        db_session,
        object_id,
        ap_object,
    )

    recipients = await _compute_recipients(db_session, ap_object)
    ap_object = ap.wrap_ap_object(ap_object)

    if ap_object["type"] == "Create":
        if ap.VisibilityEnum.PUBLIC == outbox_object.visibility:
            ldsig.generate_signature(ap_object, k)

    for r in recipients:
        await ap.post(
            r,
            ap_object,
        )

    return True


async def _compute_recipients(
        db_session: AsyncSession,
        ap_object: dict,
) -> set[str]:

    async def process_collection(
            db_session,
            url) -> list[Actor]:
        if url == BASE_URL + "/followers":
            followers = (
                (
                    await db_session.scalars(
                        select(models.Follower).options(
                            joinedload(models.Follower.actor)
                        )
                    )
                )
                .unique()
                .all()
            )
        else:
            raise ValueError(f"{url}) not supported")

        return [follower.actor for follower in followers]

    _recipients = []
    for field in ["to", "cc", "bcc", "bto"]:
        if field in ap_object:
            _recipients.extend(ap_object[field])

    recipients = set()
    logger.info(f"{_recipients}")
    for r in _recipients:
        if r in [ap.AS_PUBLIC, ID]:
            continue

        if r.startswith(BASE_URL):
            for actor in await process_collection(db_session, r):
                recipients.add(actor.share_inbox_url)

            continue

    return recipients


async def save_to_inbox(
        db_session : AsyncSession,
        inbox_id : str,
        ap_object : dict,
        relates_to_inbox_object_id: int | None = None,
        relates_to_outbox_object_id: int | None = None,
        relates_to_actor_id: int | None = None,
) -> InboxObject:

    ap_type = ap_object["type"]
    ap_id = ap_object["id"]
    visibility = handle_visibility(ap_object)

    inbox_object = OutboxObject(
        public_id=inbox_id,
        ap_object=ap_object,
        ap_id=ap_id,
        ap_type=ap_type,
        visibility =visibility,
        relates_to_inbox_object_id=relates_to_inbox_object_id,
        relates_to_outbox_object_id=relates_to_outbox_object_id,
        relates_to_actor_id=relates_to_actor_id,
    )

    db_session.add(inbox_object)
    await db_session.flush()
    await db_session.refresh(inbox_object)

    return inbox_object


async def save_to_outbox(
        db_session : AsyncSession,
        outbox_id : str,
        ap_object : dict,
        relates_to_inbox_object_id: int | None = None,
        relates_to_outbox_object_id: int | None = None,
        relates_to_actor_id: int | None = None,
) -> OutboxObject:
    ap_type = ap_object["type"]
    ap_id = ap_object["id"]
    visibility = handle_visibility(ap_object)

    outbox_object = OutboxObject(
        public_id=outbox_id,
        ap_object=ap_object,
        ap_id=ap_id,
        ap_type=ap_type,
        visibility =visibility,
        relates_to_inbox_object_id=relates_to_inbox_object_id,
        relates_to_outbox_object_id=relates_to_outbox_object_id,
        relates_to_actor_id=relates_to_actor_id,
    )

    db_session.add(outbox_object)
    await db_session.flush()
    await db_session.refresh(outbox_object)
    await db_session.commit()

    return outbox_object