from flask import Flask, jsonify
import gps
import threading
import time

app = Flask(__name__)

# GPS data container
current_gps_data = {
    "latitude": None,
    "longitude": None,
    "altitude": None,
    "speed": None,
    "timestamp": None
}

# Global gps session object
session = gps.gps(mode=gps.WATCH_ENABLE | gps.WATCH_NEWSTYLE)

def gps_monitor():
    global current_gps_data
    while True:
        try:
            # Wait for new data from the GPS device
            report = session.next()
            if report['class'] == 'TPV':
                current_gps_data = {
                    "latitude": report.get('lat', None),
                    "longitude": report.get('lon', None),
                    "altitude": report.get('alt', None),
                    "speed": report.get('speed', None),
                    "timestamp": report.get('time', None)
                }
        except gps.GPSException as e:
            print(f"GPS Error: {e}")
        except KeyError as e:
            print(f"Missing Key: {e}")
        time.sleep(1)

@app.route('/gps', methods=['GET'])
def get_gps_data():
    """API endpoint to fetch current GPS data"""
    if None in current_gps_data.values():
        return jsonify({"error": "No GPS data available yet"}), 404
    return jsonify(current_gps_data)

if __name__ == '__main__':
    # Start GPS monitoring in a separate thread
    gps_thread = threading.Thread(target=gps_monitor)
    gps_thread.daemon = True  # This makes the thread exit when the program does
    gps_thread.start()

    # Run the Flask web service
    app.run(host='0.0.0.0', port=5000)