"""
Client MinIO/S3 asincrono per il worker.

Percorso EML raw:  pecflow/tenants/{tenant_id}/mailboxes/{mailbox_id}/raw/{uid}.eml
Percorso allegati: pecflow/tenants/{tenant_id}/mailboxes/{mailbox_id}/attachments/{msg_id}/{filename}
"""

import io
import logging
from functools import lru_cache

from miniopy_async import Minio

from app.config import get_settings

logger = logging.getLogger(__name__)
settings = get_settings()


@lru_cache(maxsize=1)
def get_minio_client() -> Minio:
    """Restituisce l'istanza singleton del client MinIO."""
    return Minio(
        endpoint=settings.minio_endpoint,
        access_key=settings.minio_access_key,
        secret_key=settings.minio_secret_key,
        secure=settings.minio_use_ssl,
    )


async def upload_eml(
    tenant_id: str,
    mailbox_id: str,
    uid: int,
    eml_bytes: bytes,
) -> str:
    """
    Carica un raw EML su MinIO e restituisce il percorso oggetto.

    Percorso: tenants/{tenant_id}/mailboxes/{mailbox_id}/raw/{uid}.eml
    """
    client = get_minio_client()
    bucket = settings.minio_bucket
    object_path = f"tenants/{tenant_id}/mailboxes/{mailbox_id}/raw/{uid}.eml"

    try:
        data_stream = io.BytesIO(eml_bytes)
        await client.put_object(
            bucket_name=bucket,
            object_name=object_path,
            data=data_stream,
            length=len(eml_bytes),
            content_type="message/rfc822",
        )
        logger.debug(f"EML caricato: s3://{bucket}/{object_path} ({len(eml_bytes)} bytes)")
        return object_path
    except Exception as e:
        logger.error(f"Errore upload EML {object_path}: {e}")
        raise


async def ensure_bucket_exists() -> None:
    """Verifica che il bucket MinIO esista, altrimenti lo crea."""
    client = get_minio_client()
    bucket = settings.minio_bucket
    try:
        found = await client.bucket_exists(bucket)
        if not found:
            await client.make_bucket(bucket)
            logger.info(f"Bucket MinIO creato: {bucket}")
        else:
            logger.debug(f"Bucket MinIO esistente: {bucket}")
    except Exception as e:
        logger.warning(f"Impossibile verificare/creare bucket MinIO: {e}")