import subprocess
import requests
import sys
from datetime import datetime
import time
import random
import signal

# arbitrarily chosen prime numbers
SLEEP_MIN = 127
SLEEP_MAX = 157


def get_slurm_status_status(username):
    """Get the status of the slurm nodes for a given user."""
    output = subprocess.check_output(
        ['squeue', '-u', username, '-h', '-o', '"%i %N %T"']).decode('utf-8')

    # parse output and return a set of status lines
    output = output.strip('" \n').split('\n')

    outputSet = set()
    for line in output:
        line = line.strip('" ')
        if line:
            outputSet.add(line)

    return outputSet


def send_notification(post_url, message):
    """Send notification via HTTP POST."""
    response = requests.post(post_url, data=message, headers={
        "Title": "Slurm Status Update",
        "Priority": "max",
        "Tags": "computer"
    })
    if response.status_code != 200:
        raise Exception(
            f"Failed HTTP POST with {response.status_code}")


def monitor_slurm_status(username, post_url):
    """Monitor the slurm status and send notifications for changes."""

    previous_status = set()

    while True:
        current_status = get_slurm_status_status(username)

        # Check for changes in the nodes
        added_status = current_status - previous_status
        removed_status = previous_status - current_status

        # Send a notification if there are any changes
        if added_status:
            print(f"{datetime.now()} Added: {added_status}")
            message = "; ".join(added_status)

            # send a notification only if any of the added lines contain "RUNNING"
            if any("RUNNING" in line for line in added_status):
                send_notification(post_url, message)
                print(f"{datetime.now()} Notification sent: {message}")

        if removed_status:
            print(f"{datetime.now()} Removed: {removed_status}")

        # Update the previous nodes
        previous_status = current_status

    # sleep for a random interval betwen 127 and 157 seconds
        time.sleep(random.randint(SLEEP_MIN, SLEEP_MAX))


if __name__ == '__main__':
    # first argument is the username to monitor
    username = sys.argv[1]

    # second argument is the URL to send the notification
    post_url = sys.argv[2]

    # trap SIGINT
    def signal_handler(sig, frame):
        print("Exiting...")
        sys.exit(0)

    signal.signal(signal.SIGINT, signal_handler)

    monitor_slurm_status(username, post_url)