import os
import smtplib
import logging
from datetime import datetime
from email.mime.text import MIMEText
from email.mime.multipart import MIMEMultipart
from dotenv import load_dotenv

# Configure logging
logging.basicConfig(
    level=logging.INFO,
    format='%(asctime)s - %(levelname)s - %(message)s',
    handlers=[
        logging.StreamHandler(),
        logging.FileHandler('email_sender.log')
    ]
)
logger = logging.getLogger(__name__)

def send_email(subject, body):
    # Start logging
    logger.info("="*50)
    logger.info(f"Starting email sending process at {datetime.now()}")
    logger.info("-"*50)
    
    try:
        # Load environment variables
        load_dotenv()
        logger.info("Environment variables loaded successfully")
        
        # Email configuration
        smtp_server = os.getenv('SMTP_SERVER')
        smtp_port = int(os.getenv('SMTP_PORT', '587'))
        smtp_username = os.getenv('SMTP_USERNAME')
        smtp_password = os.getenv('SMTP_PASSWORD')
        from_email = os.getenv('SMTP_FROM')
        to_email = os.getenv('SMTP_TO')
        use_tls = os.getenv('SMTP_USE_TLS', 'True').lower() == 'true'
        
        # Log configuration
        logger.info(f"SMTP Server: {smtp_server}:{smtp_port}")
        logger.info(f"From: {from_email}")
        logger.info(f"To: {to_email}")
        logger.info(f"Use TLS: {use_tls}")
        logger.info(f"Subject: {subject}")
        logger.debug(f"Email body: {body}")

        # Create message
        logger.info("Creating email message...")
        msg = MIMEMultipart()
        msg['From'] = from_email
        msg['To'] = to_email
        msg['Subject'] = subject
        msg.attach(MIMEText(body, 'plain'))
        logger.debug("Email message created successfully")

        # Create SMTP session
        logger.info(f"Connecting to SMTP server: {smtp_server}:{smtp_port}")
        with smtplib.SMTP(smtp_server, smtp_port, timeout=30) as server:
            logger.info("SMTP connection established")
            
            if use_tls:
                logger.info("Starting TLS encryption...")
                server.starttls()
                logger.info("TLS encryption started")
            
            # Login to SMTP server
            logger.info("Authenticating with SMTP server...")
            try:
                server.login(smtp_username, smtp_password)
                logger.info("Successfully authenticated with SMTP server")
            except Exception as auth_error:
                logger.error(f"SMTP authentication failed: {str(auth_error)}")
                logger.error(f"Username used: {smtp_username}")
                raise
            
            # Send email
            logger.info("Sending email...")
            server.send_message(msg)
            logger.info("Email sent successfully!")
            logger.info(f"Email details - From: {from_email}, To: {to_email}, Subject: {subject}")
            return True
            
    except smtplib.SMTPException as smtp_error:
        logger.error(f"SMTP Error occurred: {str(smtp_error)}")
        logger.error(f"SMTP Error code: {getattr(smtp_error, 'smtp_code', 'N/A')}")
        logger.error(f"SMTP Error message: {getattr(smtp_error, 'smtp_error', 'N/A')}")
        return False
    except Exception as e:
        logger.error(f"Unexpected error occurred: {str(e)}", exc_info=True)
        return False
    finally:
        logger.info("="*50 + "\n")

if __name__ == "__main__":
    try:
        # Test email
        subject = "SMTP Test Email"
        body = "This is a test email sent using Python's smtplib with SMTP on port 587."
        
        logger.info("Starting email test...")
        result = send_email(subject, body)
        
        if result:
            logger.info("Email test completed successfully!")
        else:
            logger.error("Email test failed!")
            
    except Exception as e:
        logger.critical(f"Critical error in main: {str(e)}", exc_info=True)