email_sender_api.py

from flask import Flask, request, jsonify
from flask_cors import CORS
import smtplib
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
from email.mime.base import MIMEBase
from email import encoders
import base64
import os

app = Flask(__name__) # Make sure your Flask app instance is named 'app'
CORS(app)

# Environment variables will be set as Secrets in Hugging Face Space settings
SMTP_SERVER_HOST = os.environ.get("SMTP_SERVER_HOST")
SMTP_SERVER_PORT = os.environ.get("SMTP_SERVER_PORT")
SMTP_SENDER_EMAIL = os.environ.get("SMTP_SENDER_EMAIL")
SMTP_SENDER_PASSWORD = os.environ.get("SMTP_SENDER_PASSWORD")

@app.route('/send-report-via-email', methods=['POST'])
def handle_send_email():
    print("EMAIL_SENDER_API (HF): Received request at /send-report-via-email")
    if not all([SMTP_SERVER_HOST, SMTP_SERVER_PORT, SMTP_SENDER_EMAIL, SMTP_SENDER_PASSWORD]):
        error_msg = "EMAIL_SENDER_API (HF): ERROR - SMTP environment variables (Secrets) not fully set."
        print(error_msg)
        return jsonify({"status": "error", "message": "Email server configuration incomplete on the API."}), 500
    
    try:
        SMTP_PORT_INT = int(SMTP_SERVER_PORT)
    except ValueError:
        error_msg = "EMAIL_SENDER_API (HF): ERROR - Invalid SMTP_SERVER_PORT configured."
        print(error_msg)
        return jsonify({"status": "error", "message": "Invalid email server port configured on the API."}), 500

    data = request.json
    if not data:
        print("EMAIL_SENDER_API (HF): No JSON data received.")
        return jsonify({"status": "error", "message": "No data received by email API."}), 400

    recipient_email = data.get('recipient_email')
    pdf_base64_data = data.get('pdf_base64_data')
    pdf_filename = data.get('pdf_filename')
    print(f"EMAIL_SENDER_API (HF): Attempting to send to: {recipient_email}, Filename: {pdf_filename}")

    if not all([recipient_email, pdf_base64_data, pdf_filename]):
        print("EMAIL_SENDER_API (HF): Missing required data in JSON payload.")
        return jsonify({"status": "error", "message": "Missing required data: recipient_email, pdf_base64_data, or pdf_filename."}), 400

    try:
        msg = MIMEMultipart()
        msg['From'] = SMTP_SENDER_EMAIL
        msg['To'] = recipient_email
        msg['Subject'] = f"EPIC-AMP Analysis Report: {pdf_filename}"
        body = f"""Dear User,\n\nPlease find your EPIC-AMP analysis report attached.\n\nFilename: {pdf_filename}\n\nThis report includes details on your sequence analysis.\n\nThank you for using EPIC-AMP!\n\nBest regards,\nThe EPIC-AMP Team\nBioinformatics and Computational Biology Unit, Zewail City\nFor inquiries: [email protected]"""
        msg.attach(MIMEText(body, 'plain'))

        pdf_data_bytes = base64.b64decode(pdf_base64_data)
        part = MIMEBase('application', 'octet-stream')
        part.set_payload(pdf_data_bytes)
        encoders.encode_base64(part)
        part.add_header('Content-Disposition', f"attachment; filename=\"{pdf_filename}\"")
        msg.attach(part)

        print(f"EMAIL_SENDER_API (HF): Connecting to SMTP server {SMTP_SERVER_HOST}:{SMTP_PORT_INT}")
        with smtplib.SMTP(SMTP_SERVER_HOST, SMTP_PORT_INT) as server:
            server.set_debuglevel(1) 
            server.ehlo()
            if SMTP_PORT_INT == 587:
                print("EMAIL_SENDER_API (HF): Starting TLS...")
                server.starttls()
                server.ehlo()
            print("EMAIL_SENDER_API (HF): Logging in...")
            server.login(SMTP_SENDER_EMAIL, SMTP_SENDER_PASSWORD)
            print("EMAIL_SENDER_API (HF): Sending mail...")
            server.sendmail(SMTP_SENDER_EMAIL, recipient_email, msg.as_string())
            print("EMAIL_SENDER_API (HF): Mail sent.")
        
        success_msg = f"Report successfully sent to {recipient_email}."
        print(f"EMAIL_SENDER_API (HF): {success_msg}")
        return jsonify({"status": "success", "message": success_msg}), 200

    except smtplib.SMTPAuthenticationError as e:
        error_msg = f"EMAIL_SENDER_API (HF): SMTP Authentication Error - {e}"
        print(error_msg)
        return jsonify({"status": "error", "message": "Email server authentication failed on the API."}), 500
    except Exception as e:
        import traceback
        error_msg = f"EMAIL_SENDER_API (HF): Error sending email to {recipient_email} - {e}"
        print(error_msg)
        print(traceback.format_exc())
        return jsonify({"status": "error", "message": f"Failed to send email via API: {e}"}), 500

# This __main__ block is mostly for local testing.
# On Hugging Face Spaces with Gunicorn, Gunicorn directly imports and runs the 'app' object.
# if __name__ == '__main__':
#     port = int(os.environ.get("PORT", 7860)) # Default port for HF Spaces if not overridden
#     print(f"Starting Email Sender API Service on port {port} locally...")
#     app.run(host='0.0.0.0', port=port, debug=True)