"""Extension that provides weather station related commands to the server, and
allow weather station providers to register themselves.
"""

from inspect import isawaitable

from flockwave.gps.vectors import GPSCoordinate
from trio import sleep_forever

from flockwave.server.message_hub import MessageHub
from flockwave.server.model.client import Client
from flockwave.server.model.messages import FlockwaveMessage, FlockwaveResponse
from flockwave.server.model.weather import Weather
from flockwave.server.registries import WeatherProviderRegistry, find_in_registry

registry = WeatherProviderRegistry()
"""Registry containing the registered weather providers by ID."""


async def handle_WTH_AT(message: FlockwaveMessage, sender: Client, hub: MessageHub):
    body = {}
    position = message.body.get("position")
    if not isinstance(position, list) or len(position) < 2:
        return hub.acknowledge(
            message, outcome=False, reason="Invalid GPS coordinate provided"
        )

    if registry.num_entries > 0:
        gps_coordinate = GPSCoordinate.from_json(position)
        weather = Weather(position=gps_coordinate)
        for provider in registry.iter_providers_by_priority():
            result = provider(weather, gps_coordinate)
            if isawaitable(result):
                await result
        body["weather"] = weather

    return body


async def handle_WTH_INF(
    message: FlockwaveMessage, sender: Client, hub: MessageHub
) -> FlockwaveResponse:
    statuses = {}

    body = {"status": statuses, "type": "WTH-INF"}
    response = hub.create_response_or_notification(body=body, in_response_to=message)

    for station_id in message.get_ids():
        provider = find_in_registry(
            registry,
            station_id,
            response=response,
            failure_reason="No such weather provider",
        )
        if provider:
            weather = Weather()
            result = provider(weather, None)
            if isawaitable(result):
                await result
            statuses[station_id] = weather

    return response


def handle_WTH_LIST(message: FlockwaveMessage, sender: Client, hub: MessageHub):
    return {"ids": list(registry.ids)}


async def run(app):
    """Unloads the extension."""
    with app.message_hub.use_message_handlers(
        {
            "WTH-AT": handle_WTH_AT,
            "WTH-INF": handle_WTH_INF,
            "WTH-LIST": handle_WTH_LIST,
        }
    ):
        await sleep_forever()


description = "Basic support for weather stations"
exports = {"add_provider": registry.add, "use_provider": registry.use}
schema = {}