import os
import smtplib
import logging
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart
from threading import Thread

logger = logging.getLogger(__name__)

def _send_email_async(subject: str, body: str):
    """Internal function running on a background thread to send the email."""
    smtp_host = os.environ.get('SMTP_HOST')
    smtp_port = os.environ.get('SMTP_PORT', '587')
    smtp_user = os.environ.get('SMTP_USER')
    smtp_pass = os.environ.get('SMTP_PASSWORD')
    to_email = 'sales@freshbeats.ai'
    
    # If credentials are not configured, print to logs/stdout and exit cleanly
    if not smtp_host or not smtp_user or not smtp_pass:
        logger.warning("Email notification skipped: SMTP environment variables (SMTP_HOST, SMTP_USER, SMTP_PASSWORD) are not fully configured.")
        logger.info(f"[Email Stub to {to_email}] Subject: {subject}\nBody:\n{body}")
        return
        
    try:
        # Create message
        msg = MIMEMultipart()
        msg['From'] = smtp_user
        msg['To'] = to_email
        msg['Subject'] = subject
        
        msg.attach(MIMEText(body, 'plain'))
        
        # Connect and send
        server = smtplib.SMTP(smtp_host, int(smtp_port), timeout=10)
        server.starttls()
        server.login(smtp_user, smtp_pass)
        server.sendmail(smtp_user, to_email, msg.as_string())
        server.quit()
        logger.info(f"Notification email successfully sent to {to_email}")
        
    except Exception as e:
        logger.error(f"Failed to send SMTP notification email to {to_email}: {e}")

def send_notification_email(subject: str, body: str):
    """
    Sends a notification email to sales@freshbeats.ai.
    This runs asynchronously on a background thread to prevent blocking the request lifecycle.
    """
    # Only execute if running in HuggingFace Spaces environment
    if os.environ.get('HF_SPACE', '0') == '1':
        thread = Thread(target=_send_email_async, args=(subject, body))
        thread.daemon = True
        thread.start()
    else:
        logger.info(f"Local development mode - skipping HF email alert: {subject}")