"""Resolve RDG client workstation (session host) from event internal_ip."""

from __future__ import annotations

from sqlalchemy import or_, select
from sqlalchemy.orm import Session

from app.models import Event, Host
from app.services.rdg_session_flap import event_internal_ip
from app.services.winrm_connect import is_windows_host


class ClientWorkstationNotFoundError(Exception):
    def __init__(self, internal_ip: str) -> None:
        self.internal_ip = internal_ip
        super().__init__(
            f"Client workstation not found in SAC hosts for internal_ip={internal_ip}. "
            "Ensure the PC is registered with matching ipv4."
        )


def find_windows_host_by_ipv4(db: Session, ipv4: str) -> Host | None:
    ip = (ipv4 or "").strip()
    if not ip:
        return None
    rows = db.scalars(
        select(Host)
        .where(
            Host.ipv4 == ip,
            or_(
                Host.os_family.ilike("windows"),
                Host.product == "rdp-login-monitor",
            ),
        )
        .order_by(Host.last_seen_at.desc())
    ).all()
    for host in rows:
        if is_windows_host(host):
            return host
    return None


def resolve_client_workstation(db: Session, event: Event) -> Host:
    internal_ip = event_internal_ip(event)
    if not internal_ip:
        raise ClientWorkstationNotFoundError("")
    host = find_windows_host_by_ipv4(db, internal_ip)
    if host is None:
        raise ClientWorkstationNotFoundError(internal_ip)
    return host