"""Ubiquiti AirOS base class."""

from __future__ import annotations

from abc import ABC
import asyncio
from collections.abc import Callable
from http.cookies import SimpleCookie
import json
import logging
from ssl import SSLError
from typing import Any, Generic, TypeVar
from urllib.parse import urlparse

import aiohttp
from mashumaro.exceptions import InvalidFieldValue, MissingField

from .data import (
    AirOSDataBaseClass,
    DerivedWirelessMode,
    DerivedWirelessRole,
    redact_data_smart,
)
from .exceptions import (
    AirOSConnectionAuthenticationError,
    AirOSConnectionSetupError,
    AirOSDataMissingError,
    AirOSDeviceConnectionError,
    AirOSKeyDataMissingError,
    AirOSMultipleMatchesFoundException,
    AirOSTLSCompatibilityError,
    AirOSUrlNotFoundError,
)
from .model_map import UispAirOSProductMapper

_LOGGER = logging.getLogger(__name__)

AirOSDataModel = TypeVar("AirOSDataModel", bound=AirOSDataBaseClass)


class AirOS(ABC, Generic[AirOSDataModel]):
    """AirOS connection class."""

    data_model: type[AirOSDataModel]

    def __init__(
        self,
        data_model: type[AirOSDataModel],
        host: str,
        username: str,
        password: str,
        session: aiohttp.ClientSession,
        *,
        use_ssl: bool = True,
    ):
        """Initialize AirOS class."""
        self.data_model = data_model
        self.username = username
        self.password = password

        self.api_version: int = 8

        parsed_host = urlparse(host)
        scheme = parsed_host.scheme or ("https" if use_ssl else "http")
        hostname = parsed_host.hostname or host

        self.base_url = f"{scheme}://{hostname}"

        self.session = session

        self._use_json_for_login_post = False
        self._auth_cookie: str | None = None
        self._csrf_id: str | None = None
        self.connected: bool = False
        self.current_csrf_token: str | None = None

        # Mostly 8.x API endpoints, login/status are the same in 6.x
        self._login_url = f"{self.base_url}/api/auth"
        self._status_cgi_url = f"{self.base_url}/status.cgi"
        self._reboot_cgi_url = f"{self.base_url}/reboot.cgi"

        # Presumed 6.x XM only endpoint
        self._v6_xm_login_url = f"{self.base_url}/login.cgi"
        self._v6_form_url = "/index.cgi"

        # Presumed 8.x only endpoints
        self._stakick_cgi_url = f"{self.base_url}/stakick.cgi"
        self._provmode_url = f"{self.base_url}/api/provmode"
        self._warnings_url = f"{self.base_url}/api/warnings"
        self._update_check_url = f"{self.base_url}/api/fw/update-check"
        self._download_url = f"{self.base_url}/api/fw/download"
        self._download_progress_url = f"{self.base_url}/api/fw/download-progress"
        self._install_url = f"{self.base_url}/fwflash.cgi"

        self._login_urls = [self._login_url, self._v6_xm_login_url]

    @staticmethod
    def _derived_wireless_data(
        derived: dict[str, Any], response: dict[str, Any]
    ) -> dict[str, Any]:
        """Add derived wireless data to the device response."""
        # Access Point / Station vs PTP/PtMP
        wireless_mode = response.get("wireless", {}).get("mode", "")
        match wireless_mode:
            case "ap-ptmp":
                derived["access_point"] = True
                derived["ptmp"] = True
                derived["role"] = DerivedWirelessRole.ACCESS_POINT
                derived["mode"] = DerivedWirelessMode.PTMP
            case "sta-ptmp":
                derived["station"] = True
                derived["ptmp"] = True
                derived["mode"] = DerivedWirelessMode.PTMP
            case "ap-ptp":
                derived["access_point"] = True
                derived["ptp"] = True
                derived["role"] = DerivedWirelessRole.ACCESS_POINT
            case "sta-ptp":
                derived["station"] = True
                derived["ptp"] = True
        return derived

    @staticmethod
    def _derived_data_helper(
        response: dict[str, Any],
        derived_wireless_data_func: Callable[
            [dict[str, Any], dict[str, Any]], dict[str, Any]
        ],
    ) -> dict[str, Any]:
        """Add derived data to the device response."""
        sku: str = "UNKNOWN"

        devmodel = (response.get("host") or {}).get("devmodel", "UNKNOWN")
        try:
            sku = UispAirOSProductMapper().get_sku_by_devmodel(devmodel)
        except KeyError:
            _LOGGER.warning(
                "Unknown SKU/Model ID for '%s'. Please report at "
                "https://github.com/CoMPaTech/python-airos/issues so we can add support.",
                devmodel,
            )
            sku = "UNKNOWN"
        except AirOSMultipleMatchesFoundException as err:  # pragma: no cover
            _LOGGER.warning(
                "Multiple SKU/Model ID matches found for model '%s': %s. Please report at "
                "https://github.com/CoMPaTech/python-airos/issues so we can add support.",
                devmodel,
                err,
            )
            sku = "AMBIGUOUS"

        derived: dict[str, Any] = {
            "station": False,
            "access_point": False,
            "ptp": False,
            "ptmp": False,
            "role": DerivedWirelessRole.STATION,
            "mode": DerivedWirelessMode.PTP,
            "sku": sku,
        }

        # WIRELESS
        derived = derived_wireless_data_func(derived, response)

        # Interfaces / MAC (for unique id)
        interfaces = response.get("interfaces", [])
        # No interfaces, no mac, no usability
        if not interfaces:
            _LOGGER.error("Failed to determine interfaces from AirOS data")
            raise AirOSKeyDataMissingError from None

        derived["mac"] = AirOS.get_mac(interfaces)["mac"]
        derived["mac_interface"] = AirOS.get_mac(interfaces)["mac_interface"]

        # Firmware Major Version
        fwversion = (response.get("host") or {}).get("fwversion", "invalid")
        derived["fw_major"] = AirOS.get_fw_major(fwversion)

        response["derived"] = derived

        return response

    @staticmethod
    def get_fw_major(fwversion: str) -> int:
        """Extract major firmware version from fwversion string."""
        try:
            return int(fwversion.lstrip("v").split(".", 1)[0])
        except (ValueError, AttributeError) as err:
            _LOGGER.error("Invalid firmware version '%s'", fwversion)
            raise AirOSKeyDataMissingError("invalid fwversion") from err

    @staticmethod
    def get_mac(interfaces: list[dict[str, Any]]) -> dict[str, str]:
        """Extract MAC address from interfaces."""
        result: dict[str, str] = {"mac": "", "mac_interface": ""}

        if not interfaces:
            return result

        addresses: dict[str, str] = {}
        interface_order = ["br0", "eth0", "ath0"]

        for interface in interfaces:
            if (
                interface.get("enabled")
                and interface.get("hwaddr")
                and interface.get("ifname")
            ):
                addresses[interface["ifname"]] = interface["hwaddr"]

        for preferred in interface_order:
            if preferred in addresses:
                result["mac"] = addresses[preferred]
                result["mac_interface"] = preferred
                break
        else:
            result["mac"] = interfaces[0].get("hwaddr", "")
            result["mac_interface"] = interfaces[0].get("ifname", "")

        return result

    @classmethod
    def derived_data(cls, response: dict[str, Any]) -> dict[str, Any]:
        """Add derived data to the device response (instance method for polymorphism)."""
        return cls._derived_data_helper(response, cls._derived_wireless_data)

    def _get_authenticated_headers(
        self,
        ct_json: bool = False,
        ct_form: bool = False,
    ) -> dict[str, str]:
        """Construct headers for an authenticated request."""
        headers = {}
        if ct_json:
            headers["Content-Type"] = "application/json"
        elif ct_form:
            headers["Content-Type"] = "application/x-www-form-urlencoded"

        if self._csrf_id:  # pragma: no cover
            headers["X-CSRF-ID"] = self._csrf_id

        if self._auth_cookie:  # pragma: no cover
            # headers["Cookie"] = f"AIROS_{self._auth_cookie}"
            headers["Cookie"] = self._auth_cookie

        return headers

    def _store_auth_data(self, response: aiohttp.ClientResponse) -> None:
        """Parse the response from a successful login and store auth data."""
        self._csrf_id = response.headers.get("X-CSRF-ID")

        # Parse all Set-Cookie headers to ensure we don't miss AIROS_* cookie
        cookie = SimpleCookie()
        for set_cookie in response.headers.getall("Set-Cookie", []):
            cookie.load(set_cookie)
        for key, morsel in cookie.items():
            if key.startswith("AIROS_"):
                # self._auth_cookie = morsel.key[6:] + "=" + morsel.value
                self._auth_cookie = f"{morsel.key}={morsel.value}"
                break

    async def _request_json(
        self,
        method: str,
        url: str,
        *,
        headers: dict[str, Any] | None = None,
        json_data: dict[str, Any] | None = None,
        form_data: dict[str, Any] | None = None,
        authenticated: bool = False,
        ct_json: bool = False,
        ct_form: bool = False,
    ) -> dict[str, Any] | Any:
        """Make an authenticated API request and return JSON response."""
        # Pass the content type flags to the header builder
        request_headers = (
            self._get_authenticated_headers(ct_json=ct_json, ct_form=ct_form)
            if authenticated
            else {}
        )
        if headers:
            request_headers.update(headers)

        try:
            if url not in self._login_urls and not self.connected:
                _LOGGER.error("Not connected, login first")
                raise AirOSDeviceConnectionError from None

            async with self.session.request(
                method,
                url,
                json=json_data,
                data=form_data,
                headers=request_headers,  # Pass the constructed headers
            ) as response:
                response.raise_for_status()
                response_text = await response.text()
                _LOGGER.debug("Successfully fetched JSON from %s", url)

                # If this is the login request, we need to store the new auth data
                if url in self._login_urls:
                    self._store_auth_data(response)
                    self.connected = True

                return json.loads(response_text)
        except aiohttp.ClientResponseError as err:
            _LOGGER.error(
                "Request to %s failed with status %s: %s", url, err.status, err.message
            )
            if err.status in [401, 403]:
                raise AirOSConnectionAuthenticationError from err
            if err.status == 404:
                raise AirOSUrlNotFoundError from err
            raise AirOSConnectionSetupError from err
        except aiohttp.ClientConnectorSSLError as err:
            if _is_tls_compatibility_error(err):
                _LOGGER.exception("TLS compatibility error during API call to %s", url)
                raise AirOSTLSCompatibilityError from err
            raise AirOSDeviceConnectionError from err
        except (TimeoutError, aiohttp.ClientError) as err:
            _LOGGER.exception("Error during API call to %s", url)
            raise AirOSDeviceConnectionError from err
        except json.JSONDecodeError as err:
            _LOGGER.error("Failed to decode JSON from %s", url)
            raise AirOSDataMissingError from err
        except asyncio.CancelledError:
            _LOGGER.warning("Request to %s was cancelled", url)
            raise

    async def _login_v6(self) -> None:
        """Login to airOS v6 (XM) devices."""
        # Handle session cookie from login url
        async with self.session.request(
            "GET",
            self._v6_xm_login_url,
            allow_redirects=False,
        ) as response:
            session_cookie = next(
                (c for n, c in response.cookies.items() if n.startswith("AIROS")), None
            )
            if not session_cookie:
                raise AirOSDeviceConnectionError("No session cookie received.")
            self._auth_cookie = f"{session_cookie.key}={session_cookie.value}"

        # Handle login expecting 302 redirect
        payload = {
            "username": self.username,
            "password": self.password,
            "uri": self._v6_form_url,
        }
        headers = {
            "Content-Type": "application/x-www-form-urlencoded",
            "Origin": self.base_url,
            "Referer": self._v6_xm_login_url,
            "Cookie": self._auth_cookie,
        }
        async with self.session.request(
            "POST",
            self._v6_xm_login_url,
            data=payload,
            headers=headers,
            allow_redirects=False,
        ) as response:
            if response.status != 302:
                raise AirOSConnectionAuthenticationError("Login failed.")

        # Activate session by accessing the form URL
        headers = {"Referer": self._v6_xm_login_url, "Cookie": self._auth_cookie}
        async with self.session.request(
            "GET",
            f"{self.base_url}{self._v6_form_url}",
            headers=headers,
            allow_redirects=True,
        ) as response:
            if "login.cgi" in str(response.url):
                raise AirOSConnectionAuthenticationError("Session activation failed.")
        self.connected = True
        self.api_version = 6

    async def login(self) -> None:
        """Login to AirOS device."""
        payload = {"username": self.username, "password": self.password}
        try:
            await self._request_json("POST", self._login_url, json_data=payload)
        except AirOSUrlNotFoundError:
            await self._login_v6()
        except AirOSConnectionSetupError as err:
            raise AirOSConnectionSetupError("Failed to login to AirOS device") from err
        else:
            return

    async def raw_status(self) -> dict[str, Any]:
        """Retrieve raw status from the device."""
        return await self._request_json("GET", self._status_cgi_url, authenticated=True)

    async def status(self) -> AirOSDataModel:
        """Retrieve status from the device."""
        response = await self._request_json(
            "GET", self._status_cgi_url, authenticated=True
        )

        try:
            adjusted_json = self.derived_data(response)
            return self.data_model.from_dict(adjusted_json)
        except InvalidFieldValue as err:
            # Log with .error() as this is a specific, known type of issue
            redacted_data = redact_data_smart(response)
            _LOGGER.error(
                "Failed to deserialize AirOS data due to an invalid field value: %s",
                redacted_data,
            )
            raise AirOSKeyDataMissingError from err
        except MissingField as err:
            # Log with .exception() for a full stack trace
            redacted_data = redact_data_smart(response)
            _LOGGER.exception(
                "Failed to deserialize AirOS data due to a missing field: %s",
                redacted_data,
            )
            raise AirOSKeyDataMissingError from err

    async def update_check(self, force: bool = False) -> dict[str, Any]:
        """Check for firmware updates."""
        if force:
            return await self._request_json(
                "POST",
                self._update_check_url,
                json_data={"force": True},
                authenticated=True,
                ct_form=True,
            )
        return await self._request_json(
            "POST",
            self._update_check_url,
            json_data={},
            authenticated=True,
            ct_json=True,
        )

    async def stakick(self, mac_address: str | None = None) -> bool:
        """Reconnect client station."""
        if not mac_address:
            _LOGGER.error("Device mac-address missing")
            raise AirOSDataMissingError from None

        payload = {"staif": "ath0", "staid": mac_address.upper()}

        await self._request_json(
            "POST",
            self._stakick_cgi_url,
            form_data=payload,
            ct_form=True,
            authenticated=True,
        )
        return True

    async def reboot(self) -> bool:
        """Reboot/restart device."""
        payload = {"reboot": "yes"}

        result = await self._request_json(
            "POST",
            self._reboot_cgi_url,
            form_data=payload,
            ct_form=True,
            authenticated=True,
        )

        ok_value = result.get("ok")
        return ok_value is True or ok_value == "true"

    async def provmode(self, active: bool = False) -> bool:
        """Set provisioning mode."""
        action = "stop"
        if active:
            action = "start"

        payload = {"action": action}
        await self._request_json(
            "POST",
            self._provmode_url,
            form_data=payload,
            ct_form=True,
            authenticated=True,
        )
        return True

    async def warnings(self) -> dict[str, Any]:
        """Get warnings."""
        return await self._request_json("GET", self._warnings_url, authenticated=True)

    async def progress(self) -> dict[str, Any]:
        """Get download progress for updates."""
        payload: dict[str, Any] = {}
        return await self._request_json(
            "POST",
            self._download_progress_url,
            json_data=payload,
            ct_json=True,
            authenticated=True,
        )

    async def download(self) -> dict[str, Any]:
        """Download new firmware."""
        payload: dict[str, Any] = {}
        return await self._request_json(
            "POST",
            self._download_url,
            json_data=payload,
            ct_json=True,
            authenticated=True,
        )

    async def install(self) -> dict[str, Any]:
        """Install new firmware."""
        payload: dict[str, Any] = {"do_update": 1}
        return await self._request_json(
            "POST",
            self._install_url,
            json_data=payload,
            ct_json=True,
            authenticated=True,
        )


def _is_tls_compatibility_error(err: aiohttp.ClientConnectorSSLError) -> bool:
    """Return True for known legacy airOS TLS handshake failures."""
    if "SSLV3_ALERT_HANDSHAKE_FAILURE" in str(err):
        return True

    cause = err.__cause__
    if isinstance(cause, SSLError):
        message = str(cause).lower()
        return (
            "handshake failure" in message or "sslv3 alert handshake failure" in message
        )

    return False
