"""WinRM connectivity test for Windows hosts using domain admin credentials."""

from __future__ import annotations

import socket
from dataclasses import dataclass

from app.models import Host


class WinAdminNotConfiguredError(Exception):
    pass


class HostNotWindowsError(Exception):
    pass


class HostTargetMissingError(Exception):
    pass


@dataclass(frozen=True)
class WinRmTestResult:
    ok: bool
    message: str
    target: str
    hostname: str | None = None


def resolve_windows_host_target(host: Host) -> str:
    targets = iter_winrm_targets(host)
    if not targets:
        raise HostTargetMissingError("Host has no hostname or IPv4 for WinRM test")
    return targets[0]


def _netbios_name_variants(name: str | None) -> list[str]:
    """Короткое имя ПК (NetBIOS), как Enter-PSSession -ComputerName Andrisonova-PC."""
    text = (name or "").strip()
    if not text:
        return []
    short = text.split(".")[0].split("\\")[0].strip()
    if not short:
        return []
    if short.casefold() == text.casefold():
        return [short]
    return [short, text]


def _looks_like_computer_name(value: str) -> bool:
    text = value.strip()
    if not text or " " in text:
        return False
    return len(text) <= 63


def iter_winrm_targets(host: Host) -> list[str]:
    """WinRM + NTLM: сначала имя хоста (как Enter-PSSession -ComputerName), IP — последним."""
    if not is_windows_host(host):
        raise HostNotWindowsError("Host is not Windows")

    seen: set[str] = set()
    ordered: list[str] = []

    def add(value: str | None) -> None:
        text = (value or "").strip()
        if not text or text.casefold() in seen:
            return
        seen.add(text.casefold())
        ordered.append(text)

    for variant in _netbios_name_variants(host.hostname):
        add(variant)

    inventory = host.inventory if isinstance(host.inventory, dict) else {}
    computer_name = inventory.get("computer_name")
    if isinstance(computer_name, str):
        for variant in _netbios_name_variants(computer_name):
            add(variant)

    if host.display_name and _looks_like_computer_name(host.display_name):
        for variant in _netbios_name_variants(host.display_name):
            add(variant)

    add(host.ipv4)
    return ordered


def is_windows_host(host: Host) -> bool:
    if (host.os_family or "").strip().lower() == "windows":
        return True
    return (host.product or "").strip() == "rdp-login-monitor"


def test_winrm_connection(
    *,
    target: str,
    user: str,
    password: str,
    timeout_sec: int = 15,
) -> WinRmTestResult:
    target = target.strip()
    user = user.strip()
    if not target or not user or not password:
        raise WinAdminNotConfiguredError("Windows admin credentials or target missing")

    from app.services.win_admin_settings import normalize_win_admin_user

    user = normalize_win_admin_user(user)

    try:
        import winrm
    except ImportError as exc:
        raise RuntimeError("pywinrm is not installed on SAC server") from exc

    operation_timeout_sec = max(5, timeout_sec)
    read_timeout_sec = operation_timeout_sec + 15
    endpoint = f"http://{target}:5985/wsman"
    try:
        session = winrm.Session(
            endpoint,
            auth=(user, password),
            transport="ntlm",
            read_timeout_sec=read_timeout_sec,
            operation_timeout_sec=operation_timeout_sec,
        )
        result = session.run_cmd("hostname")
    except winrm.exceptions.WinRMTransportError as exc:
        detail = str(exc)
        hint = ""
        if "credentials were rejected" in detail.lower():
            hint = (
                " Проверьте логин (B26\\user), пароль и права admin на ПК; "
                "подключайтесь по имени хоста (как Enter-PSSession -ComputerName), не по IP."
            )
        return WinRmTestResult(
            ok=False,
            message=f"WinRM transport error ({target}): {detail}{hint}",
            target=target,
        )
    except (socket.timeout, TimeoutError):
        return WinRmTestResult(
            ok=False,
            message=f"WinRM timeout ({timeout_sec}s) to {target}:5985",
            target=target,
        )
    except Exception as exc:
        return WinRmTestResult(
            ok=False,
            message=f"WinRM error: {exc}",
            target=target,
        )

    stdout = (result.std_out or b"").decode("utf-8", errors="replace").strip()
    stderr = (result.std_err or b"").decode("utf-8", errors="replace").strip()
    if result.status_code == 0 and stdout:
        return WinRmTestResult(
            ok=True,
            message=f"WinRM OK, hostname={stdout}",
            target=target,
            hostname=stdout,
        )
    detail = stderr or stdout or f"exit code {result.status_code}"
    return WinRmTestResult(
        ok=False,
        message=f"WinRM command failed: {detail}",
        target=target,
    )