import os, logging, subprocess, threading
DEBUG = os.environ.get('DEBUG')
logging.basicConfig(
        format='[%(asctime)s] %(levelname)s %(module)s/%(funcName)s - %(message)s',
        level=logging.DEBUG if DEBUG else logging.INFO)

from flask import Flask, request

AUTO_STOP_TIMEOUT_SECONDS = 3600  # 1 hour
LAST_CAST_ADDRESS = None

app = Flask(__name__)
auto_stop_timer = None # Timer for automatic VNC stop

@app.route('/cast', methods=['POST'])
def cast_spell():
    global auto_stop_timer, LAST_CAST_ADDRESS

    ip_address = request.form.get('ip_address')
    logging.info(f"Received POST request on /cast. Requested ip_address: {ip_address}")

    if not ip_address:
        logging.warning(f"Invalid or missing ip_address parameter: {ip_address}")
        return f"Invalid or missing 'ip_address' parameter.", 400

    logging.info(f"Casting to {ip_address}.")
    kill_vnc()  # Kill any existing VNC session first
    cast_machine(ip_address)
    LAST_CAST_ADDRESS = ip_address

    # Restart auto-stop timer
    if auto_stop_timer is not None and auto_stop_timer.is_alive():
        auto_stop_timer.cancel()
        logging.info("Cancelled previous auto-stop timer.")
    auto_stop_timer = threading.Timer(AUTO_STOP_TIMEOUT_SECONDS, _auto_stop_vnc)
    auto_stop_timer.start()
    logging.info(f"Scheduled auto-stop for VNC in {AUTO_STOP_TIMEOUT_SECONDS} seconds.")

    return f"Successfully cast to {ip_address}.", 200

@app.route('/stop', methods=['POST'])
def stop_cast():
    global auto_stop_timer, LAST_CAST_ADDRESS

    ip_address = request.form.get('ip_address')
    logging.info(f"Received POST request on /stop for ip_address: {ip_address}")

    if not ip_address:
        logging.warning(f"Invalid or missing ip_address parameter: {ip_address}")
        return f"Invalid or missing 'ip_address' parameter.", 400

    if ip_address != LAST_CAST_ADDRESS:
        logging.warning(f"Stop request for {ip_address} does not match last cast address {LAST_CAST_ADDRESS}.")
        return f"Stop request for {ip_address} does not match last cast address.", 403

    if auto_stop_timer is not None and auto_stop_timer.is_alive():
        auto_stop_timer.cancel()
        auto_stop_timer = None
        logging.info("Manual stop: auto-stop timer cancelled.")
    
    kill_vnc()
    LAST_CAST_ADDRESS = None

    return "Attempted to stop VNC viewers.", 200

def _auto_stop_vnc():
    """Called by the timer to automatically stop VNC."""
    global auto_stop_timer
    logging.info("Auto-stopping VNC viewers due to inactivity timer.")
    kill_vnc()
    auto_stop_timer = None # Clear the timer reference

def cast_machine(ip_address):
    """Executes the xtightvncviewer command for a given IP address."""
    command = f"DISPLAY=:1 xtightvncviewer -viewonly -fullscreen {ip_address}"
    try:
        logging.info(f"Launching command: {command}")
        # Use Popen to run the command in the background (non-blocking)
        subprocess.Popen(command, shell=True)
        logging.info(f"Command '{command}' launched successfully.")
    except Exception as e: # Catch other potential errors during Popen
        logging.error(f"An error occurred while launching VNC for {ip_address} with Popen: {e}")

def kill_vnc():
    """Executes the killall command for xtightvncviewer."""
    command = "killall xtightvncviewer"
    try:
        logging.info(f"Executing command: {command}")
        # We don't use check=True here because killall returns a non-zero exit code
        # if no processes were killed, which is not necessarily an error in this context.
        result = subprocess.run(command, shell=True, capture_output=True, text=True)
        if result.returncode == 0:
            logging.info("killall command executed successfully. Processes were likely terminated.")
        else:
            # killall returns 1 if no matching processes were found.
            # Other non-zero codes might indicate other errors.
            logging.warning(f"killall command finished. Exit code: {result.returncode}. Stderr: {result.stderr.strip()}")
            if "no process found" in result.stderr.lower():
                 logging.info("No xtightvncviewer processes were found to kill.")

    except Exception as e:
        logging.error(f"An unexpected error occurred while trying to run killall: {e}")

def main():
    app.run(debug=DEBUG, host='0.0.0.0', port=int(os.environ.get('PORT', 5000)))

if __name__ == '__main__':
    main()