"""Config flow to configure the MJPEG IP Camera integration."""
from __future__ import annotations

from http import HTTPStatus
from types import MappingProxyType
from typing import Any

import requests
from requests.auth import HTTPBasicAuth, HTTPDigestAuth
from requests.exceptions import HTTPError, Timeout
import voluptuous as vol

from homeassistant.config_entries import ConfigEntry, ConfigFlow, OptionsFlow
from homeassistant.const import (
    CONF_AUTHENTICATION,
    CONF_NAME,
    CONF_PASSWORD,
    CONF_USERNAME,
    CONF_VERIFY_SSL,
    HTTP_BASIC_AUTHENTICATION,
    HTTP_DIGEST_AUTHENTICATION,
)
from homeassistant.core import HomeAssistant, callback
from homeassistant.data_entry_flow import FlowResult
from homeassistant.exceptions import HomeAssistantError

from .const import CONF_MJPEG_URL, CONF_STILL_IMAGE_URL, DOMAIN, LOGGER


@callback
def async_get_schema(
    defaults: dict[str, Any] | MappingProxyType[str, Any], show_name: bool = False
) -> vol.Schema:
    """Return MJPEG IP Camera schema."""
    schema = {
        vol.Required(CONF_MJPEG_URL, default=defaults.get(CONF_MJPEG_URL)): str,
        vol.Optional(
            CONF_STILL_IMAGE_URL,
            description={"suggested_value": defaults.get(CONF_STILL_IMAGE_URL)},
        ): str,
        vol.Optional(
            CONF_USERNAME,
            description={"suggested_value": defaults.get(CONF_USERNAME)},
        ): str,
        vol.Optional(
            CONF_PASSWORD,
            default=defaults.get(CONF_PASSWORD, ""),
        ): str,
        vol.Optional(
            CONF_VERIFY_SSL,
            default=defaults.get(CONF_VERIFY_SSL, True),
        ): bool,
    }

    if show_name:
        schema = {
            vol.Optional(CONF_NAME, default=defaults.get(CONF_NAME)): str,
            **schema,
        }

    return vol.Schema(schema)


def validate_url(
    url: str,
    username: str | None,
    password: str,
    verify_ssl: bool,
    authentication: str = HTTP_BASIC_AUTHENTICATION,
) -> str:
    """Test if the given setting works as expected."""
    auth: HTTPDigestAuth | HTTPBasicAuth | None = None
    if username and password:
        if authentication == HTTP_DIGEST_AUTHENTICATION:
            auth = HTTPDigestAuth(username, password)
        else:
            auth = HTTPBasicAuth(username, password)

    response = requests.get(
        url,
        auth=auth,
        stream=True,
        timeout=10,
        verify=verify_ssl,
    )

    if response.status_code == HTTPStatus.UNAUTHORIZED:
        # If unauthorized, try again using digest auth
        if authentication == HTTP_BASIC_AUTHENTICATION:
            return validate_url(
                url, username, password, verify_ssl, HTTP_DIGEST_AUTHENTICATION
            )
        raise InvalidAuth

    response.raise_for_status()
    response.close()

    return authentication


async def async_validate_input(
    hass: HomeAssistant, user_input: dict[str, Any]
) -> tuple[dict[str, str], str]:
    """Manage MJPEG IP Camera options."""
    errors = {}
    field = "base"
    authentication = HTTP_BASIC_AUTHENTICATION
    try:
        for field in (CONF_MJPEG_URL, CONF_STILL_IMAGE_URL):
            if not (url := user_input.get(field)):
                continue
            authentication = await hass.async_add_executor_job(
                validate_url,
                url,
                user_input.get(CONF_USERNAME),
                user_input[CONF_PASSWORD],
                user_input[CONF_VERIFY_SSL],
            )
    except InvalidAuth:
        errors["username"] = "invalid_auth"
    except (OSError, HTTPError, Timeout):
        LOGGER.exception("Cannot connect to %s", user_input[CONF_MJPEG_URL])
        errors[field] = "cannot_connect"

    return (errors, authentication)


class MJPEGFlowHandler(ConfigFlow, domain=DOMAIN):
    """Config flow for MJPEG IP Camera."""

    VERSION = 1

    @staticmethod
    @callback
    def async_get_options_flow(
        config_entry: ConfigEntry,
    ) -> MJPEGOptionsFlowHandler:
        """Get the options flow for this handler."""
        return MJPEGOptionsFlowHandler(config_entry)

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

        if user_input is not None:
            errors, authentication = await async_validate_input(self.hass, user_input)
            if not errors:
                self._async_abort_entries_match(
                    {CONF_MJPEG_URL: user_input[CONF_MJPEG_URL]}
                )

                # Storing data in option, to allow for changing them later
                # using an options flow.
                return self.async_create_entry(
                    title=user_input.get(CONF_NAME, user_input[CONF_MJPEG_URL]),
                    data={},
                    options={
                        CONF_AUTHENTICATION: authentication,
                        CONF_MJPEG_URL: user_input[CONF_MJPEG_URL],
                        CONF_PASSWORD: user_input[CONF_PASSWORD],
                        CONF_STILL_IMAGE_URL: user_input.get(CONF_STILL_IMAGE_URL),
                        CONF_USERNAME: user_input.get(CONF_USERNAME),
                        CONF_VERIFY_SSL: user_input[CONF_VERIFY_SSL],
                    },
                )
        else:
            user_input = {}

        return self.async_show_form(
            step_id="user",
            data_schema=async_get_schema(user_input, show_name=True),
            errors=errors,
        )


class MJPEGOptionsFlowHandler(OptionsFlow):
    """Handle MJPEG IP Camera options."""

    def __init__(self, config_entry: ConfigEntry) -> None:
        """Initialize MJPEG IP Camera options flow."""
        self.config_entry = config_entry

    async def async_step_init(
        self, user_input: dict[str, Any] | None = None
    ) -> FlowResult:
        """Manage MJPEG IP Camera options."""
        errors: dict[str, str] = {}

        if user_input is not None:
            errors, authentication = await async_validate_input(self.hass, user_input)
            if not errors:
                for entry in self.hass.config_entries.async_entries(DOMAIN):
                    if (
                        entry.entry_id != self.config_entry.entry_id
                        and entry.options[CONF_MJPEG_URL] == user_input[CONF_MJPEG_URL]
                    ):
                        errors = {CONF_MJPEG_URL: "already_configured"}

                if not errors:
                    return self.async_create_entry(
                        title=user_input.get(CONF_NAME, user_input[CONF_MJPEG_URL]),
                        data={
                            CONF_AUTHENTICATION: authentication,
                            CONF_MJPEG_URL: user_input[CONF_MJPEG_URL],
                            CONF_PASSWORD: user_input[CONF_PASSWORD],
                            CONF_STILL_IMAGE_URL: user_input.get(CONF_STILL_IMAGE_URL),
                            CONF_USERNAME: user_input.get(CONF_USERNAME),
                            CONF_VERIFY_SSL: user_input[CONF_VERIFY_SSL],
                        },
                    )
        else:
            user_input = {}

        return self.async_show_form(
            step_id="init",
            data_schema=async_get_schema(user_input or self.config_entry.options),
            errors=errors,
        )


class InvalidAuth(HomeAssistantError):
    """Error to indicate there is invalid auth."""