import os
from prometheus_client import Counter, start_http_server

_METRICS_STARTED = False

NS = os.getenv("METRICS_NS", "servicestask")
SERVICE_NAME = os.getenv("SERVICE_NAME", "db-service")

QUEUE_ENQUEUED = Counter(
    f"{NS}_queue_enqueued_total", "Enqueued tasks",
    labelnames=("service","queue","type")
)
QUEUE_DUPLICATE = Counter(
    f"{NS}_queue_duplicate_skipped_total", "Duplicate skipped",
    labelnames=("service","queue","type")
)
QUEUE_DONE = Counter(
    f"{NS}_queue_done_total", "Done tasks",
    labelnames=("service","queue","type")
)
QUEUE_FAILED = Counter(
    f"{NS}_queue_failed_total", "Failed tasks",
    labelnames=("service","queue","type")
)
QUEUE_RETRY = Counter(
    f"{NS}_queue_retry_total", "Retry attempts",
    labelnames=("service","queue","type")
)

def start_server():
    global _METRICS_STARTED
    if _METRICS_STARTED:
        return
    port = int(os.getenv("METRICS_PORT", "8000"))
    start_http_server(port)
    _METRICS_STARTED = True

def observe(status: str, queue: str, type_: str):
    labels = (SERVICE_NAME, queue, type_ or "unknown")
    if status == "enqueued":
        QUEUE_ENQUEUED.labels(*labels).inc()
    elif status == "duplicate_skipped":
        QUEUE_DUPLICATE.labels(*labels).inc()
    elif status == "done":
        QUEUE_DONE.labels(*labels).inc()
    elif status == "failed":
        QUEUE_FAILED.labels(*labels).inc()
    elif status == "retry":
        QUEUE_RETRY.labels(*labels).inc()