intercept/routes/sensor.py

"""RTL_433 sensor monitoring routes."""

from __future__ import annotations

import json
import queue
import subprocess
import threading
import time
from datetime import datetime
from typing import Generator

from flask import Blueprint, jsonify, request, Response

import app as app_module
from utils.logging import sensor_logger as logger
from utils.validation import validate_frequency, validate_device_index, validate_gain, validate_ppm
from utils.sse import format_sse
from utils.process import safe_terminate, register_process
from utils.sdr import SDRFactory, SDRType

sensor_bp = Blueprint('sensor', __name__)


def stream_sensor_output(process: subprocess.Popen[bytes]) -> None:
    """Stream rtl_433 JSON output to queue."""
    try:
        app_module.sensor_queue.put({'type': 'status', 'text': 'started'})

        for line in iter(process.stdout.readline, b''):
            line = line.decode('utf-8', errors='replace').strip()
            if not line:
                continue

            try:
                # rtl_433 outputs JSON objects, one per line
                data = json.loads(line)
                data['type'] = 'sensor'
                app_module.sensor_queue.put(data)

                # Log if enabled
                if app_module.logging_enabled:
                    try:
                        with open(app_module.log_file_path, 'a') as f:
                            timestamp = datetime.now().strftime('%Y-%m-%d %H:%M:%S')
                            f.write(f"{timestamp} | {data.get('model', 'Unknown')} | {json.dumps(data)}\n")
                    except Exception:
                        pass
            except json.JSONDecodeError:
                # Not JSON, send as raw
                app_module.sensor_queue.put({'type': 'raw', 'text': line})

    except Exception as e:
        app_module.sensor_queue.put({'type': 'error', 'text': str(e)})
    finally:
        process.wait()
        app_module.sensor_queue.put({'type': 'status', 'text': 'stopped'})
        with app_module.sensor_lock:
            app_module.sensor_process = None


@sensor_bp.route('/start_sensor', methods=['POST'])
def start_sensor() -> Response:
    with app_module.sensor_lock:
        if app_module.sensor_process:
            return jsonify({'status': 'error', 'message': 'Sensor already running'}), 409

        data = request.json or {}

        # Validate inputs
        try:
            freq = validate_frequency(data.get('frequency', '433.92'))
            gain = validate_gain(data.get('gain', '0'))
            ppm = validate_ppm(data.get('ppm', '0'))
            device = validate_device_index(data.get('device', '0'))
        except ValueError as e:
            return jsonify({'status': 'error', 'message': str(e)}), 400

        # Clear queue
        while not app_module.sensor_queue.empty():
            try:
                app_module.sensor_queue.get_nowait()
            except queue.Empty:
                break

        # Get SDR type and build command via abstraction layer
        sdr_type_str = data.get('sdr_type', 'rtlsdr')
        try:
            sdr_type = SDRType(sdr_type_str)
        except ValueError:
            sdr_type = SDRType.RTL_SDR

        # Create device object and get command builder
        sdr_device = SDRFactory.create_default_device(sdr_type, index=device)
        builder = SDRFactory.get_builder(sdr_type)

        # Build ISM band decoder command
        cmd = builder.build_ism_command(
            device=sdr_device,
            frequency_mhz=freq,
            gain=float(gain) if gain and gain != 0 else None,
            ppm=int(ppm) if ppm and ppm != 0 else None
        )

        full_cmd = ' '.join(cmd)
        logger.info(f"Running: {full_cmd}")

        try:
            app_module.sensor_process = subprocess.Popen(
                cmd,
                stdout=subprocess.PIPE,
                stderr=subprocess.PIPE,
                bufsize=1
            )

            # Start output thread
            thread = threading.Thread(target=stream_sensor_output, args=(app_module.sensor_process,))
            thread.daemon = True
            thread.start()

            # Monitor stderr
            def monitor_stderr():
                for line in app_module.sensor_process.stderr:
                    err = line.decode('utf-8', errors='replace').strip()
                    if err:
                        logger.debug(f"[rtl_433] {err}")
                        app_module.sensor_queue.put({'type': 'info', 'text': f'[rtl_433] {err}'})

            stderr_thread = threading.Thread(target=monitor_stderr)
            stderr_thread.daemon = True
            stderr_thread.start()

            app_module.sensor_queue.put({'type': 'info', 'text': f'Command: {full_cmd}'})

            return jsonify({'status': 'started', 'command': full_cmd})

        except FileNotFoundError:
            return jsonify({'status': 'error', 'message': 'rtl_433 not found. Install with: brew install rtl_433'})
        except Exception as e:
            return jsonify({'status': 'error', 'message': str(e)})


@sensor_bp.route('/stop_sensor', methods=['POST'])
def stop_sensor() -> Response:
    with app_module.sensor_lock:
        if app_module.sensor_process:
            app_module.sensor_process.terminate()
            try:
                app_module.sensor_process.wait(timeout=2)
            except subprocess.TimeoutExpired:
                app_module.sensor_process.kill()
            app_module.sensor_process = None
            return jsonify({'status': 'stopped'})

        return jsonify({'status': 'not_running'})


@sensor_bp.route('/stream_sensor')
def stream_sensor() -> Response:
    def generate() -> Generator[str, None, None]:
        last_keepalive = time.time()
        keepalive_interval = 30.0

        while True:
            try:
                msg = app_module.sensor_queue.get(timeout=1)
                last_keepalive = time.time()
                yield format_sse(msg)
            except queue.Empty:
                now = time.time()
                if now - last_keepalive >= keepalive_interval:
                    yield format_sse({'type': 'keepalive'})
                    last_keepalive = now

    response = Response(generate(), mimetype='text/event-stream')
    response.headers['Cache-Control'] = 'no-cache'
    response.headers['X-Accel-Buffering'] = 'no'
    response.headers['Connection'] = 'keep-alive'
    return response