"""Config flow to configure the Obihai integration."""

from __future__ import annotations

from socket import gaierror, gethostbyname
from typing import Any

from pyobihai import PyObihai
import voluptuous as vol

from homeassistant.components import dhcp
from homeassistant.config_entries import ConfigFlow, ConfigFlowResult
from homeassistant.const import CONF_HOST, CONF_PASSWORD, CONF_USERNAME
from homeassistant.core import HomeAssistant
from homeassistant.helpers.device_registry import format_mac

from .connectivity import validate_auth
from .const import DEFAULT_PASSWORD, DEFAULT_USERNAME, DOMAIN

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


async def async_validate_creds(
    hass: HomeAssistant, user_input: dict[str, Any]
) -> PyObihai | None:
    """Manage Obihai options."""

    if user_input[CONF_USERNAME] and user_input[CONF_PASSWORD]:
        return await hass.async_add_executor_job(
            validate_auth,
            user_input[CONF_HOST],
            user_input[CONF_USERNAME],
            user_input[CONF_PASSWORD],
        )

    # Don't bother authenticating if we've already determined the credentials are invalid
    return None


class ObihaiFlowHandler(ConfigFlow, domain=DOMAIN):
    """Config flow for Obihai."""

    VERSION = 2
    discovery_schema: vol.Schema | None = None
    _dhcp_discovery_info: dhcp.DhcpServiceInfo | None = None

    async def async_step_user(
        self, user_input: dict[str, Any] | None = None
    ) -> ConfigFlowResult:
        """Handle a flow initialized by the user."""

        errors: dict[str, str] = {}
        ip: str | None = None

        if user_input is not None:
            try:
                ip = await self.hass.async_add_executor_job(
                    gethostbyname, user_input[CONF_HOST]
                )
            except gaierror:
                errors["base"] = "cannot_connect"

            if ip:
                if pyobihai := await async_validate_creds(self.hass, user_input):
                    device_mac = await self.hass.async_add_executor_job(
                        pyobihai.get_device_mac
                    )
                    await self.async_set_unique_id(format_mac(device_mac))
                    self._abort_if_unique_id_configured()

                    return self.async_create_entry(
                        title=user_input[CONF_HOST],
                        data=user_input,
                    )
                errors["base"] = "invalid_auth"

        data_schema = self.discovery_schema or DATA_SCHEMA
        return self.async_show_form(
            step_id="user",
            errors=errors,
            data_schema=self.add_suggested_values_to_schema(data_schema, user_input),
        )

    async def async_step_dhcp(
        self, discovery_info: dhcp.DhcpServiceInfo
    ) -> ConfigFlowResult:
        """Prepare configuration for a DHCP discovered Obihai."""

        self._dhcp_discovery_info = discovery_info
        return await self.async_step_dhcp_confirm()

    async def async_step_dhcp_confirm(
        self, user_input: dict[str, Any] | None = None
    ) -> ConfigFlowResult:
        """Attempt to confirm."""
        assert self._dhcp_discovery_info
        await self.async_set_unique_id(format_mac(self._dhcp_discovery_info.macaddress))
        self._abort_if_unique_id_configured()

        if user_input is None:
            credentials = {
                CONF_HOST: self._dhcp_discovery_info.ip,
                CONF_PASSWORD: DEFAULT_PASSWORD,
                CONF_USERNAME: DEFAULT_USERNAME,
            }
            if await async_validate_creds(self.hass, credentials):
                self.discovery_schema = self.add_suggested_values_to_schema(
                    DATA_SCHEMA, credentials
                )
            else:
                self.discovery_schema = self.add_suggested_values_to_schema(
                    DATA_SCHEMA,
                    {
                        CONF_HOST: self._dhcp_discovery_info.ip,
                        CONF_USERNAME: "",
                        CONF_PASSWORD: "",
                    },
                )

            # Show the confirmation dialog
            return self.async_show_form(
                step_id="dhcp_confirm",
                data_schema=self.discovery_schema,
                description_placeholders={CONF_HOST: self._dhcp_discovery_info.ip},
            )

        return await self.async_step_user(user_input=user_input)