"""Config flow for AVM FRITZ!SmartHome."""
from urllib.parse import urlparse

from pyfritzhome import Fritzhome, LoginError
from requests.exceptions import HTTPError
import voluptuous as vol

from homeassistant import config_entries
from homeassistant.components.ssdp import (
    ATTR_SSDP_LOCATION,
    ATTR_UPNP_FRIENDLY_NAME,
    ATTR_UPNP_UDN,
)
from homeassistant.const import CONF_HOST, CONF_PASSWORD, CONF_USERNAME

from .const import DEFAULT_HOST, DEFAULT_USERNAME, DOMAIN

DATA_SCHEMA_USER = vol.Schema(
    {
        vol.Required(CONF_HOST, default=DEFAULT_HOST): str,
        vol.Required(CONF_USERNAME, default=DEFAULT_USERNAME): str,
        vol.Required(CONF_PASSWORD): str,
    }
)

DATA_SCHEMA_CONFIRM = vol.Schema(
    {
        vol.Required(CONF_USERNAME, default=DEFAULT_USERNAME): str,
        vol.Required(CONF_PASSWORD): str,
    }
)

RESULT_INVALID_AUTH = "invalid_auth"
RESULT_NO_DEVICES_FOUND = "no_devices_found"
RESULT_NOT_SUPPORTED = "not_supported"
RESULT_SUCCESS = "success"


class FritzboxConfigFlow(config_entries.ConfigFlow, domain=DOMAIN):
    """Handle a AVM FRITZ!SmartHome config flow."""

    VERSION = 1

    def __init__(self):
        """Initialize flow."""
        self._entry = None
        self._host = None
        self._name = None
        self._password = None
        self._username = None

    def _get_entry(self):
        return self.async_create_entry(
            title=self._name,
            data={
                CONF_HOST: self._host,
                CONF_PASSWORD: self._password,
                CONF_USERNAME: self._username,
            },
        )

    async def _update_entry(self):
        self.hass.config_entries.async_update_entry(
            self._entry,
            data={
                CONF_HOST: self._host,
                CONF_PASSWORD: self._password,
                CONF_USERNAME: self._username,
            },
        )
        await self.hass.config_entries.async_reload(self._entry.entry_id)

    def _try_connect(self):
        """Try to connect and check auth."""
        fritzbox = Fritzhome(
            host=self._host, user=self._username, password=self._password
        )
        try:
            fritzbox.login()
            fritzbox.get_device_elements()
            fritzbox.logout()
            return RESULT_SUCCESS
        except LoginError:
            return RESULT_INVALID_AUTH
        except HTTPError:
            return RESULT_NOT_SUPPORTED
        except OSError:
            return RESULT_NO_DEVICES_FOUND

    async def async_step_user(self, user_input=None):
        """Handle a flow initialized by the user."""
        errors = {}

        if user_input is not None:
            self._async_abort_entries_match({CONF_HOST: user_input[CONF_HOST]})

            self._host = user_input[CONF_HOST]
            self._name = user_input[CONF_HOST]
            self._password = user_input[CONF_PASSWORD]
            self._username = user_input[CONF_USERNAME]

            result = await self.hass.async_add_executor_job(self._try_connect)

            if result == RESULT_SUCCESS:
                return self._get_entry()
            if result != RESULT_INVALID_AUTH:
                return self.async_abort(reason=result)
            errors["base"] = result

        return self.async_show_form(
            step_id="user", data_schema=DATA_SCHEMA_USER, errors=errors
        )

    async def async_step_ssdp(self, discovery_info):
        """Handle a flow initialized by discovery."""
        host = urlparse(discovery_info[ATTR_SSDP_LOCATION]).hostname
        self.context[CONF_HOST] = host

        uuid = discovery_info.get(ATTR_UPNP_UDN)
        if uuid:
            if uuid.startswith("uuid:"):
                uuid = uuid[5:]
            await self.async_set_unique_id(uuid)
            self._abort_if_unique_id_configured({CONF_HOST: host})

        for progress in self._async_in_progress():
            if progress.get("context", {}).get(CONF_HOST) == host:
                return self.async_abort(reason="already_in_progress")

        # update old and user-configured config entries
        for entry in self.hass.config_entries.async_entries(DOMAIN):
            if entry.data[CONF_HOST] == host:
                if uuid and not entry.unique_id:
                    self.hass.config_entries.async_update_entry(entry, unique_id=uuid)
                return self.async_abort(reason="already_configured")

        self._host = host
        self._name = discovery_info.get(ATTR_UPNP_FRIENDLY_NAME) or host

        self.context["title_placeholders"] = {"name": self._name}
        return await self.async_step_confirm()

    async def async_step_confirm(self, user_input=None):
        """Handle user-confirmation of discovered node."""
        errors = {}

        if user_input is not None:
            self._password = user_input[CONF_PASSWORD]
            self._username = user_input[CONF_USERNAME]
            result = await self.hass.async_add_executor_job(self._try_connect)

            if result == RESULT_SUCCESS:
                return self._get_entry()
            if result != RESULT_INVALID_AUTH:
                return self.async_abort(reason=result)
            errors["base"] = result

        return self.async_show_form(
            step_id="confirm",
            data_schema=DATA_SCHEMA_CONFIRM,
            description_placeholders={"name": self._name},
            errors=errors,
        )

    async def async_step_reauth(self, data):
        """Trigger a reauthentication flow."""
        self._entry = self.hass.config_entries.async_get_entry(self.context["entry_id"])
        self._host = data[CONF_HOST]
        self._name = data[CONF_HOST]
        self._username = data[CONF_USERNAME]

        return await self.async_step_reauth_confirm()

    async def async_step_reauth_confirm(self, user_input=None):
        """Handle reauthorization flow."""
        errors = {}

        if user_input is not None:
            self._password = user_input[CONF_PASSWORD]
            self._username = user_input[CONF_USERNAME]

            result = await self.hass.async_add_executor_job(self._try_connect)

            if result == RESULT_SUCCESS:
                await self._update_entry()
                return self.async_abort(reason="reauth_successful")
            if result != RESULT_INVALID_AUTH:
                return self.async_abort(reason=result)
            errors["base"] = result

        return self.async_show_form(
            step_id="reauth_confirm",
            data_schema=vol.Schema(
                {
                    vol.Required(CONF_USERNAME, default=self._username): str,
                    vol.Required(CONF_PASSWORD): str,
                }
            ),
            description_placeholders={"name": self._name},
            errors=errors,
        )