#!/usr/bin/env python3
import os
import json
from flask import Flask, request, jsonify, Response
import logging
import sys
from dotenv import load_dotenv # Import load_dotenv

# --- Configuration Loading ---
# Load environment variables from from $HOME/.env and ./.env files
# $HOME/.env allows for user-specific settings, ./.env for project-specific settings.
# Values in ./.env might override $HOME/.env if load_dotenv is called again without override=False
# or if the variable exists in both and override=True is used on the second call.
# Current approach: Load $HOME/.env first, then load ./.env allowing ./.env to add or override.
logging.info("Loading environment variables...")
home_dotenv_path = os.path.join(os.environ.get("HOME", "."), '.env')
project_dotenv_path = os.path.join(os.getcwd(), '.env')

if os.path.exists(home_dotenv_path):
    logging.info(f"Loading environment variables from: {home_dotenv_path}")
    load_dotenv(dotenv_path=home_dotenv_path)
else:
    logging.info(f"Optional environment file not found: {home_dotenv_path}")

if os.path.exists(project_dotenv_path):
    logging.info(f"Loading environment variables from: {project_dotenv_path}")
    # load_dotenv will not override existing variables by default.
    # Use override=True if you want ./.env to forcefully replace variables from $HOME/.env
    load_dotenv(dotenv_path=project_dotenv_path, override=True)
else:
    logging.info(f"Project environment file not found: {project_dotenv_path}")


# --- Configuration ---
# Now loaded from environment variables defined in the .env files
TELNYX_API_KEY = os.environ.get("TELNYX_API_KEY") # Used for making API calls (e.g., sending messages)
TELNYX_SENDER_ID = os.environ.get("TELNYX_SENDER_ID") # Default 'from' number if sending messages via API
TELNYX_CONNECTION_ID = os.environ.get("TELNYX_CONNECTION_ID") # Used for Voice/TTS Calls via API
TELNYX_MESSAGING_PROFILE_ID = os.environ.get("TELNYX_MESSAGING_PROFILE_ID") # Associated messaging profile
TELNYX_PUBLIC_KEY = os.environ.get("TELNYX_PUBLIC_KEY") # REQUIRED if enabling signature validation

# --- Other Configurations ---
# Keyword can also be moved to .env if preferred
OPT_IN_KEYWORD = os.environ.get("OPT_IN_KEYWORD", "WELLNUOJOIN") # Load from env or default

# Configure logging (after potentially loading log level from env)
LOG_LEVEL = os.environ.get("LOG_LEVEL", "INFO").upper()
logging.basicConfig(level=LOG_LEVEL, format='%(asctime)s - %(levelname)s - %(message)s', stream=sys.stdout) # Log to stdout for containers/systemd


# --- Verification ---
if not TELNYX_PUBLIC_KEY:
     logging.warning("TELNYX_PUBLIC_KEY is not set in environment variables. Signature validation will be skipped.")
# Add checks for other essential variables if needed for specific functions

app = Flask(__name__)

# --- Database Interaction Placeholder ---
# (Keep your existing database functions here)
def add_opted_in_number(phone_number):
    logging.info(f"Adding phone number to opt-in list: {phone_number}")
    print(f"DATABASE STUB: Adding {phone_number} to opt-ins.")
    # Replace with your actual DB logic
    return True

def is_opted_in(phone_number):
    logging.info(f"Checking opt-in status for: {phone_number}")
    print(f"DATABASE STUB: Checking if {phone_number} is opted in.")
     # Replace with your actual DB logic
    return False
# --------------------------------------

@app.route('/webhook', methods=['POST'])
def telnyx_webhook():
    """Handles incoming webhooks from Telnyx."""
    logging.debug("Webhook received") # Use debug level for noisy logs

    # --- Telnyx Signature Validation (Using loaded TELNYX_PUBLIC_KEY) ---
    # UNCOMMENT this section if you have set TELNYX_PUBLIC_KEY in your .env file
    # and installed the 'telnyx' library.
    # ---
    # if not TELNYX_PUBLIC_KEY:
    #     logging.warning("Skipping signature validation: TELNYX_PUBLIC_KEY not configured.")
    # else:
    #     signature = request.headers.get("Telnyx-Signature-Ed25519")
    #     timestamp = request.headers.get("Telnyx-Timestamp")
    #     raw_payload = request.data # Get raw bytes
    #     if not signature or not timestamp:
    #         logging.warning("Missing Telnyx signature headers")
    #         return jsonify({"error": "Missing signature headers"}), 400
    #     try:
    #         # Requires 'telnyx' library: pip install telnyx
    #         from telnyx.webhook import Webhook
    #         Webhook.construct_event(raw_payload, signature, timestamp, TELNYX_PUBLIC_KEY, tolerance=600) # 10 min tolerance
    #         logging.info("Telnyx signature validated successfully.")
    #     except Exception as e:
    #         logging.error(f"Invalid Telnyx signature: {e}")
    #         return jsonify({"error": "Invalid signature"}), 401
    # --- End Signature Validation Section ---


    try:
        payload = request.json
        # Log the full payload only at DEBUG level to avoid excessive logging
        logging.debug(f"Payload received: {json.dumps(payload, indent=2)}")

        event_type = payload.get('data', {}).get('event_type')
        record_type = payload.get('data', {}).get('record_type')

        if event_type == 'message.received' and record_type == 'message':
            message_payload = payload.get('data', {}).get('payload', {})
            direction = message_payload.get('direction')

            if direction == 'inbound':
                from_number = message_payload.get('from', {}).get('phone_number')
                # Use the OPT_IN_KEYWORD loaded from env or default
                message_body = message_payload.get('text', '').strip().upper()

                logging.info(f"Received inbound message from {from_number}: '{message_body[:50]}'...") # Log truncated message

                if message_body == OPT_IN_KEYWORD:
                    logging.info(f"Opt-in keyword '{OPT_IN_KEYWORD}' detected from {from_number}")
                    if not is_opted_in(from_number):
                        if add_opted_in_number(from_number):
                            logging.info(f"Successfully processed opt-in for {from_number}")
                        else:
                            logging.error(f"Failed to add {from_number} to opt-in database.")
                    else:
                         logging.info(f"{from_number} is already opted in.")
                else:
                    logging.info(f"Message from {from_number} did not match opt-in keyword.")
            else:
                logging.debug(f"Ignoring non-inbound message: direction={direction}") # Use debug for less important ignores
        else:
            logging.debug(f"Ignoring non-message.received event: type={event_type}, record={record_type}") # Use debug

        # Acknowledge receipt to Telnyx
        return Response(status=204)

    except Exception as e:
        logging.exception("Error processing webhook") # Logs the full exception traceback
        return jsonify({"error": "Internal server error"}), 500

if __name__ == '__main__':
    logging.info("Starting Flask development server for local testing...")
    # Bind to 0.0.0.0 to be accessible externally if needed for local testing with ngrok/similar
    app.run(host='0.0.0.0', port=8002, debug=True) # Debug=True is NOT for production