"""Check configured infrastructure without changing production data."""
import json,uuid
from django.core.management.base import BaseCommand,CommandError
from django.db import connection
from django.db.migrations.executor import MigrationExecutor
from django.core.cache import cache
from config.celery import app

class Command(BaseCommand):
    help='Prüft Datenbank, Migrationen, Redis, Broker und optional Worker.'
    def add_arguments(self,p):p.add_argument('--workers',action='store_true')
    def handle(self,*args,**options):
        results={}
        try:
            with connection.cursor() as c:c.execute('SELECT 1');c.fetchone()
            results['database']=connection.vendor
            executor=MigrationExecutor(connection)
            pending=executor.migration_plan(executor.loader.graph.leaf_nodes())
            results['migrations']='pending' if pending else 'ok'
        except Exception as e:results['database']='ERROR '+type(e).__name__
        try:
            key='doctor:'+str(uuid.uuid4());cache.set(key,'ok',30)
            results['cache']='ok' if cache.get(key)=='ok' else 'ERROR readback'
            cache.delete(key)
        except Exception as e:results['cache']='ERROR '+type(e).__name__
        try:
            with app.connection_for_read() as conn:conn.ensure_connection(max_retries=0,timeout=5)
            results['broker']='ok'
        except Exception as e:results['broker']='ERROR '+type(e).__name__
        if options['workers']:
            try:results['workers']='ok' if app.control.ping(timeout=3) else 'ERROR no response'
            except Exception as e:results['workers']='ERROR '+type(e).__name__
        self.stdout.write(json.dumps(results,indent=2))
        if any(v.startswith('ERROR') or v=='pending' for v in results.values()):
            raise CommandError('Infrastrukturprüfung fehlgeschlagen; keine Zugangsdaten werden ausgegeben.')