# celery_app.py
from celery import Celery
import redis
from urllib.parse import urlparse
from config import get_settings

settings = get_settings()

def parse_redis_host(raw: str, default_port: int) -> tuple[str, int]:
    """
    Accept any of these formats for REDIS_HOST:
      - "my-host.upstash.io"
      - "my-host.upstash.io:6379"
      - "https://my-host.upstash.io"
      - "rediss://my-host.upstash.io:6379"
    Always returns (hostname, port).
    """
    raw = raw.strip()
    # If there's a scheme, use urlparse
    if "://" in raw:
        parsed = urlparse(raw)
        host = parsed.hostname or raw
        port = parsed.port or default_port
    elif ":" in raw:
        host, port_str = raw.rsplit(":", 1)
        port = int(port_str)
    else:
        host = raw
        port = default_port
    return host, port

REDIS_HOST, REDIS_PORT = parse_redis_host(settings.REDIS_HOST, settings.REDIS_PORT)
REDIS_PASSWORD = settings.REDIS_PASSWORD

if REDIS_PASSWORD:
    BROKER_URL  = f"rediss://:{REDIS_PASSWORD}@{REDIS_HOST}:{REDIS_PORT}/0?ssl_cert_reqs=CERT_NONE"
    BACKEND_URL = f"rediss://:{REDIS_PASSWORD}@{REDIS_HOST}:{REDIS_PORT}/0?ssl_cert_reqs=CERT_NONE"
else:
    BROKER_URL  = f"redis://{REDIS_HOST}:{REDIS_PORT}/0"
    BACKEND_URL = f"redis://{REDIS_HOST}:{REDIS_PORT}/0"

celery_app = Celery(
    "assistant_worker",
    broker=BROKER_URL,
    backend=BACKEND_URL,
    include=["generation.ExamAnswer"]
)

celery_app.conf.update(
    task_serializer="json",
    accept_content=["json"],
    result_serializer="json",
    task_track_started=True,
    task_time_limit=60 * 60,
    broker_use_ssl={"ssl_cert_reqs": "CERT_NONE"} if REDIS_PASSWORD else None,
    redis_backend_use_ssl={"ssl_cert_reqs": "CERT_NONE"} if REDIS_PASSWORD else None,
)

import worker.tasks
from generation.ExamAnswer import grade_exam_task


def clear_redis_backend():
    if REDIS_PASSWORD:
        r = redis.Redis(
            host=REDIS_HOST,
            port=REDIS_PORT,
            password=REDIS_PASSWORD,
            ssl=True,
            ssl_cert_reqs=None,
            db=0,
        )
    else:
        r = redis.Redis(host=REDIS_HOST, port=REDIS_PORT, db=0)
    r.flushdb()
    print("Redis result backend cleared!")


@celery_app.on_after_configure.connect
def setup(sender, **kwargs):
    clear_redis_backend()