import os
import requests
from flask import jsonify, request

BASE_URL = 'https://ws.audioscrobbler.com/2.0/'
RECENT_TRACKS_PARAMS = 'method=user.getrecenttracks&limit=1&format=json'
TIMEOUT = 10

def route(user):
    api_key = os.environ.get('LASTFM_API_KEY')
    if not api_key:
        return jsonify({"message": "INTERNAL_ERROR"}), 500
    try:
        req = requests.get(f"{BASE_URL}?{RECENT_TRACKS_PARAMS}&user={user}&api_key={api_key}", timeout=TIMEOUT)
        lastfm_response = req.json()
        recent_tracks = lastfm_response.get('recenttracks', {})
        if 'track' not in recent_tracks or not recent_tracks['track']:
            return jsonify({'message': 'NO_TRACKS_FOUND'}), 200
        track = recent_tracks['track'][0]
        if request.args.get('format') == 'shields.io':
            return jsonify({'schemaVersion': 1, 'label': 'Last.FM Last Played Song', 'message': f"{track['name']} - {track['artist']['#text']}"}), 200
        return jsonify({'track': track}), req.status_code
    except Exception:
        return jsonify({'message': 'INTERNAL_ERROR'}), 500