"""Prometheus-Metriken des Router-Service (eigene Registry pro Instanz)."""

from __future__ import annotations

from typing import TYPE_CHECKING

from prometheus_client import CollectorRegistry, Counter, Gauge, Histogram, generate_latest

if TYPE_CHECKING:
    from .runner import RunResult


class Metrics:
    def __init__(self) -> None:
        self.registry = CollectorRegistry()
        self.runs = Counter("knaster_runs_total", "Läufe nach Ergebnis und Endstufe", ["status", "stage"],
                            registry=self.registry)
        self.escalations = Counter("knaster_escalations_total", "Eskalationen nach Signal", ["signal"],
                                   registry=self.registry)
        self.verifier = Counter("knaster_verifier_total", "Verifier-Ergebnisse", ["skill", "stage", "passed"],
                                registry=self.registry)
        self.attempts = Histogram("knaster_run_attempts", "Versuche pro Lauf", buckets=(1, 2, 3, 4),
                                  registry=self.registry)
        self.slot_status = Gauge("knaster_slot_available", "1 = Slot verfügbar", ["slot"], registry=self.registry)
        self.open_proposals = Gauge("knaster_open_proposals", "Offene Pflege-Vorschläge", registry=self.registry)

    def observe_run(self, result: RunResult) -> None:
        self.runs.labels(result.status, str(result.stage)).inc()
        self.attempts.observe(len(result.attempts))
        for attempt in result.attempts[1:]:
            for s in attempt.decision.signals[:1]:
                self.escalations.labels(s.value).inc()
        for attempt in result.attempts:
            if attempt.verification is not None:
                self.verifier.labels(attempt.decision.skill or "-", str(attempt.decision.stage),
                                     str(attempt.verification.passed).lower()).inc()

    def render(self) -> bytes:
        return generate_latest(self.registry)