"""Config flow for IntelliFire integration."""
from __future__ import annotations

from collections.abc import Mapping
from dataclasses import dataclass
from typing import Any

from aiohttp import ClientConnectionError
from intellifire4py import AsyncUDPFireplaceFinder
from intellifire4py.exceptions import LoginException
from intellifire4py.intellifire import IntellifireAPICloud, IntellifireAPILocal
import voluptuous as vol

from homeassistant import config_entries
from homeassistant.components.dhcp import DhcpServiceInfo
from homeassistant.const import CONF_API_KEY, CONF_HOST, CONF_PASSWORD, CONF_USERNAME
from homeassistant.data_entry_flow import FlowResult

from .const import CONF_USER_ID, DOMAIN, LOGGER

STEP_USER_DATA_SCHEMA = vol.Schema({vol.Required(CONF_HOST): str})

MANUAL_ENTRY_STRING = "IP Address"  # Simplified so it does not have to be translated


@dataclass
class DiscoveredHostInfo:
    """Host info for discovery."""

    ip: str
    serial: str | None


async def validate_host_input(host: str, dhcp_mode: bool = False) -> str:
    """Validate the user input allows us to connect.

    Data has the keys from STEP_USER_DATA_SCHEMA with values provided by the user.
    """
    LOGGER.debug("Instantiating IntellifireAPI with host: [%s]", host)
    api = IntellifireAPILocal(fireplace_ip=host)
    await api.poll(supress_warnings=dhcp_mode)
    serial = api.data.serial

    LOGGER.debug("Found a fireplace: %s", serial)
    # Return the serial number which will be used to calculate a unique ID for the device/sensors
    return serial


class ConfigFlow(config_entries.ConfigFlow, domain=DOMAIN):
    """Handle a config flow for IntelliFire."""

    VERSION = 1

    def __init__(self):
        """Initialize the Config Flow Handler."""
        self._host: str = ""
        self._serial: str = ""
        self._not_configured_hosts: list[DiscoveredHostInfo] = []
        self._discovered_host: DiscoveredHostInfo
        self._reauth_needed: DiscoveredHostInfo

    async def _find_fireplaces(self):
        """Perform UDP discovery."""
        fireplace_finder = AsyncUDPFireplaceFinder()
        discovered_hosts = await fireplace_finder.search_fireplace(timeout=1)
        configured_hosts = {
            entry.data[CONF_HOST]
            for entry in self._async_current_entries(include_ignore=False)
            if CONF_HOST in entry.data  # CONF_HOST will be missing for ignored entries
        }

        self._not_configured_hosts = [
            DiscoveredHostInfo(ip, None)
            for ip in discovered_hosts
            if ip not in configured_hosts
        ]
        LOGGER.debug("Discovered Hosts: %s", discovered_hosts)
        LOGGER.debug("Configured Hosts: %s", configured_hosts)
        LOGGER.debug("Not Configured Hosts: %s", self._not_configured_hosts)

    async def validate_api_access_and_create_or_update(
        self, *, host: str, username: str, password: str, serial: str
    ):
        """Validate username/password against api."""
        LOGGER.debug("Attempting login to iftapi with: %s", username)

        ift_cloud = IntellifireAPICloud()
        await ift_cloud.login(username=username, password=password)
        api_key = ift_cloud.get_fireplace_api_key()
        user_id = ift_cloud.get_user_id()

        data = {
            CONF_HOST: host,
            CONF_PASSWORD: password,
            CONF_USERNAME: username,
            CONF_API_KEY: api_key,
            CONF_USER_ID: user_id,
        }

        # Update or Create
        existing_entry = await self.async_set_unique_id(serial)
        if existing_entry:
            self.hass.config_entries.async_update_entry(existing_entry, data=data)
            await self.hass.config_entries.async_reload(existing_entry.entry_id)
            return self.async_abort(reason="reauth_successful")
        return self.async_create_entry(title=f"Fireplace {serial}", data=data)

    async def async_step_api_config(
        self, user_input: dict[str, Any] | None = None
    ) -> FlowResult:
        """Configure API access."""

        errors = {}
        control_schema = vol.Schema(
            {
                vol.Required(CONF_USERNAME): str,
                vol.Required(CONF_PASSWORD): str,
            }
        )

        if user_input is not None:

            control_schema = vol.Schema(
                {
                    vol.Required(
                        CONF_USERNAME, default=user_input.get(CONF_USERNAME, "")
                    ): str,
                    vol.Required(
                        CONF_PASSWORD, default=user_input.get(CONF_PASSWORD, "")
                    ): str,
                }
            )

            try:
                return await self.validate_api_access_and_create_or_update(
                    host=self._host,
                    username=user_input[CONF_USERNAME],
                    password=user_input[CONF_PASSWORD],
                    serial=self._serial,
                )

            except (ConnectionError, ClientConnectionError):
                errors["base"] = "iftapi_connect"
                LOGGER.error(
                    "Could not connect to iftapi.net over https - verify connectivity"
                )
            except LoginException:
                errors["base"] = "api_error"
                LOGGER.error("Invalid credentials for iftapi.net")

        return self.async_show_form(
            step_id="api_config", errors=errors, data_schema=control_schema
        )

    async def _async_validate_ip_and_continue(self, host: str) -> FlowResult:
        """Validate local config and continue."""
        self._async_abort_entries_match({CONF_HOST: host})
        self._serial = await validate_host_input(host)
        await self.async_set_unique_id(self._serial, raise_on_progress=False)
        self._abort_if_unique_id_configured(updates={CONF_HOST: host})
        # Store current data and jump to next stage
        self._host = host

        return await self.async_step_api_config()

    async def async_step_manual_device_entry(self, user_input=None):
        """Handle manual input of local IP configuration."""
        LOGGER.debug("STEP: manual_device_entry")
        errors = {}
        self._host = user_input.get(CONF_HOST) if user_input else None
        if user_input is not None:
            try:
                return await self._async_validate_ip_and_continue(self._host)
            except (ConnectionError, ClientConnectionError):
                errors["base"] = "cannot_connect"

        return self.async_show_form(
            step_id="manual_device_entry",
            errors=errors,
            data_schema=vol.Schema({vol.Required(CONF_HOST, default=self._host): str}),
        )

    async def async_step_pick_device(
        self, user_input: dict[str, Any] | None = None
    ) -> FlowResult:
        """Pick which device to configure."""
        errors = {}
        LOGGER.debug("STEP: pick_device")

        if user_input is not None:
            if user_input[CONF_HOST] == MANUAL_ENTRY_STRING:
                return await self.async_step_manual_device_entry()

            try:
                return await self._async_validate_ip_and_continue(user_input[CONF_HOST])
            except (ConnectionError, ClientConnectionError):
                errors["base"] = "cannot_connect"

        return self.async_show_form(
            step_id="pick_device",
            errors=errors,
            data_schema=vol.Schema(
                {
                    vol.Required(CONF_HOST): vol.In(
                        [host.ip for host in self._not_configured_hosts]
                        + [MANUAL_ENTRY_STRING]
                    )
                }
            ),
        )

    async def async_step_user(
        self, user_input: dict[str, Any] | None = None
    ) -> FlowResult:
        """Start the user flow."""

        # Launch fireplaces discovery
        await self._find_fireplaces()
        LOGGER.debug("STEP: user")
        if self._not_configured_hosts:
            LOGGER.debug("Running Step: pick_device")
            return await self.async_step_pick_device()
        LOGGER.debug("Running Step: manual_device_entry")
        return await self.async_step_manual_device_entry()

    async def async_step_reauth(self, entry_data: Mapping[str, Any]) -> FlowResult:
        """Perform reauth upon an API authentication error."""
        LOGGER.debug("STEP: reauth")
        entry = self.hass.config_entries.async_get_entry(self.context["entry_id"])
        assert entry
        assert entry.unique_id

        # populate the expected vars
        self._serial = entry.unique_id
        self._host = entry.data[CONF_HOST]

        placeholders = {CONF_HOST: self._host, "serial": self._serial}
        self.context["title_placeholders"] = placeholders
        return await self.async_step_api_config()

    async def async_step_dhcp(self, discovery_info: DhcpServiceInfo) -> FlowResult:
        """Handle DHCP Discovery."""

        # Run validation logic on ip
        host = discovery_info.ip
        LOGGER.debug("STEP: dhcp for host %s", host)

        self._async_abort_entries_match({CONF_HOST: host})
        try:
            self._serial = await validate_host_input(host, dhcp_mode=True)
        except (ConnectionError, ClientConnectionError):
            LOGGER.debug(
                "DHCP Discovery has determined %s is not an IntelliFire device", host
            )
            return self.async_abort(reason="not_intellifire_device")

        await self.async_set_unique_id(self._serial)
        self._abort_if_unique_id_configured(updates={CONF_HOST: host})
        self._discovered_host = DiscoveredHostInfo(ip=host, serial=self._serial)

        placeholders = {CONF_HOST: host, "serial": self._serial}
        self.context["title_placeholders"] = placeholders
        self._set_confirm_only()

        return await self.async_step_dhcp_confirm()

    async def async_step_dhcp_confirm(self, user_input=None):
        """Attempt to confirm."""

        LOGGER.debug("STEP: dhcp_confirm")
        # Add the hosts one by one
        host = self._discovered_host.ip
        serial = self._discovered_host.serial

        if user_input is None:
            # Show the confirmation dialog
            return self.async_show_form(
                step_id="dhcp_confirm",
                description_placeholders={CONF_HOST: host, "serial": serial},
            )

        return self.async_create_entry(
            title=f"Fireplace {serial}",
            data={CONF_HOST: host},
        )