"""Motion Detection example
This example shows how to use the CSI framework to connect to a FeitCSI host and
detect changes in the environment

Once motion is detected, the application will log the change to Home Assistant
through an HTTP request.
"""

import os
from queue import Queue

import numpy as np
import numpy.typing as npt
import requests

from where_fi.application import CSIApplication
from where_fi.collection.ingest import RealtimeCSIProducer

# Connect to a FeitCSI host
producer = RealtimeCSIProducer()
app = CSIApplication(producer)


class HomeAssistantBinarySensor:
    """
    Represents a binary sensor in Home Assistant.

    Uses the HTTP API [1] to update the state of the sensor.

    [1] - https://www.home-assistant.io/integrations/http/#binary-sensor
    """

    def __init__(self, id: str, name: str) -> None:
        self.id = id
        self.name = name

        BASE_URL = os.getenv("HOME_ASSISTANT_URL")
        API_KEY = os.getenv("HOME_ASSISTANT_API_KEY")

        self.url = f"{BASE_URL}/api/states/binary_sensor.{self.id}"
        self.headers = {"Authorization": f"Bearer {API_KEY}"}

        self.state = False

    def update(self, state: bool) -> None:
        if self.state == state:
            return

        self.state = state
        data = {
            "state": "on" if state else "off",
            "attributes": {"friendly_name": self.name, "device_class": "motion"},
        }
        print(f"Updating sensor {self.name} to {data}")
        requests.post(self.url, json=data, headers=self.headers)


# Stores historical data for each receiving antenna, for each subcarrier
historical: dict[tuple[int, int], Queue[np.complex64]] = {}
sensor = HomeAssistantBinarySensor("motion_detector", "Room Motion Detector")

MAGN_THRESHOLD = 20
PHASE_THRESHOLD = 0.5
QUEUE_SIZE = 2000


@app.on_process
def _(sample: npt.NDArray[np.complex64]) -> None:
    """
    Process the CSI data and detect changes in the environment.

    This function is called by the framework at a fixed interval, with the latest CSI
    sample received.

    It is used to detect changes in the environment caused by motion, by comparing each
    entry in the matrix with a moving average
    """
    change = False
    for antenna in range(sample.shape[1]):
        for subcarrier in range(sample.shape[0]):
            # Get the current subcarrier data
            current = sample[subcarrier, antenna, 0]

            # Get the historical data for this antenna and subcarrier
            if (antenna, subcarrier) not in historical:
                historical[(antenna, subcarrier)] = Queue(maxsize=QUEUE_SIZE)
            historical_data = historical[(antenna, subcarrier)]

            # Calculate the average of the historical data for this antenna and
            # subcarrier
            mean = np.mean(historical_data.queue)

            # If we have enough historical data, compare it with the current data
            if historical_data.full():
                historical_data.get()

            # Add the current sample to the historical data
            historical_data.put(current)

            # Compare the current data with the historical data
            if (
                np.abs(mean - current) > MAGN_THRESHOLD
                or np.abs(np.angle(mean) - np.angle(current)) > PHASE_THRESHOLD
            ):
                change = True

    sensor.update(change)


app.start()