"""Onboarding views."""
import asyncio

import voluptuous as vol

from homeassistant.components.http.data_validator import RequestDataValidator
from homeassistant.components.http.view import HomeAssistantView
from homeassistant.core import callback

from .const import DOMAIN, STEP_USER, STEPS


async def async_setup(hass, data, store):
    """Set up the onboarding view."""
    hass.http.register_view(OnboardingView(data, store))
    hass.http.register_view(UserOnboardingView(data, store))


class OnboardingView(HomeAssistantView):
    """Return the onboarding status."""

    requires_auth = False
    url = '/api/onboarding'
    name = 'api:onboarding'

    def __init__(self, data, store):
        """Initialize the onboarding view."""
        self._store = store
        self._data = data

    async def get(self, request):
        """Return the onboarding status."""
        return self.json([
            {
                'step': key,
                'done': key in self._data['done'],
            } for key in STEPS
        ])


class _BaseOnboardingView(HomeAssistantView):
    """Base class for onboarding."""

    requires_auth = False
    step = None

    def __init__(self, data, store):
        """Initialize the onboarding view."""
        self._store = store
        self._data = data
        self._lock = asyncio.Lock()

    @callback
    def _async_is_done(self):
        """Return if this step is done."""
        return self.step in self._data['done']

    async def _async_mark_done(self, hass):
        """Mark step as done."""
        self._data['done'].append(self.step)
        await self._store.async_save(self._data)

        hass.data[DOMAIN] = len(self._data) == len(STEPS)


class UserOnboardingView(_BaseOnboardingView):
    """View to handle onboarding."""

    url = '/api/onboarding/users'
    name = 'api:onboarding:users'
    step = STEP_USER

    @RequestDataValidator(vol.Schema({
        vol.Required('name'): str,
        vol.Required('username'): str,
        vol.Required('password'): str,
    }))
    async def post(self, request, data):
        """Return the manifest.json."""
        hass = request.app['hass']

        async with self._lock:
            if self._async_is_done():
                return self.json_message('User step already done', 403)

            provider = _async_get_hass_provider(hass)
            await provider.async_initialize()

            user = await hass.auth.async_create_user(data['name'])
            await hass.async_add_executor_job(
                provider.data.add_auth, data['username'], data['password'])
            credentials = await provider.async_get_or_create_credentials({
                'username': data['username']
            })
            await provider.data.async_save()
            await hass.auth.async_link_user(user, credentials)
            await self._async_mark_done(hass)


@callback
def _async_get_hass_provider(hass):
    """Get the Home Assistant auth provider."""
    for prv in hass.auth.auth_providers:
        if prv.type == 'homeassistant':
            return prv

    raise RuntimeError('No Home Assistant provider found')
