import asyncio
import itertools
import logging
from typing import List, Optional

from peewee import BooleanField, CharField

import defence360agent.subsys.panels.hosting_panel as hp
from defence360agent.contracts.messages import MessageType
from defence360agent.model import Model, instance
from defence360agent.model.simplification import run_in_executor
from defence360agent.utils import execute_iterable_expression
from defence360agent.utils.config import update_config
from imav.malwarelib.model import MalwareHit

logger = logging.getLogger(__name__)


class MyImunify(Model):
    """Secure-site related settings"""

    class Meta:
        database = instance.db
        db_table = "myimunify"

    #: The username of the end-user, or an empty string for the default value
    #: for all new users.
    user = CharField(unique=True)

    #: Is MyImunify protection enabled/disabled to the end-user.
    protection = BooleanField(null=False, default=False)

    @classmethod
    def get_protection(cls, user: Optional[str]) -> bool:
        """Get SecureSite protection by username"""
        if user is None or user == "root":
            # root
            return True

        perm, _ = cls.get_or_create(user=user, defaults={"protection": False})
        return perm.protection

    @classmethod
    def update_users_protection(cls, users: List[str], status: bool):
        cls.insert_many(
            [{"user": user, "protection": status} for user in users]
        ).on_conflict(
            conflict_target=[cls.user],
            preserve=[],
            update={cls.protection: status},
        ).execute()


async def malware_cleanup(sink, user):
    hits = MalwareHit.malicious_select(user=user, cleanup=True)
    if hits:
        await sink.process_message(MessageType.MalwareCleanupTask(hits=hits))


async def update_users_protection(sink, users: List[str], status: bool):
    await run_in_executor(
        None,
        lambda: MyImunify.update_users_protection(users, status),
    )
    proactive_mode = None
    if not status:
        proactive_mode = "LOG"
    tasks = [
        update_config(
            sink,
            {"PROACTIVE_DEFENCE": {"mode": proactive_mode}},
            user,
        )
        for user in users
    ]

    if status:
        tasks += [malware_cleanup(sink, user) for user in users]

    await asyncio.gather(*tasks)


async def set_protection_status_for_all_users(sink, status: bool):
    """Set protection status for all users"""
    panel_users = await hp.HostingPanel().get_users()
    await update_users_protection(sink, panel_users, status)


async def sync_users(sink, users: List[str]) -> bool:
    """Synchronize existing permissions with myimunify users"""
    panel_users = set(users)

    myimunify_users = MyImunify.select(MyImunify.user)
    myimunify_users = set(itertools.chain(*myimunify_users.tuples()))

    users_to_remove = myimunify_users - panel_users

    if users_to_remove:
        logger.info("Remove myimunify users %s", users_to_remove)

        def expression(users_to_remove):
            return MyImunify.delete().where(
                MyImunify.user.in_(users_to_remove)
            )

        execute_iterable_expression(expression, list(users_to_remove))

    users_to_add = panel_users - myimunify_users

    if users_to_add:
        logger.info("Add permissions to users %s", users_to_add)
        await update_users_protection(sink, users, False)
    return bool(users_to_add) or bool(users_to_remove)