"""
Zähler für produktive OpenRouter-Aufrufe innerhalb einer Planungs-API-Anfrage.

Wird per ContextVar gesetzt (Router: ``planning_llm_call_meter``); ``openrouter_chat_completion``
erhöht den Zähler nach erfolgreicher Antwort — nur wenn ein Meter aktiv ist.
"""
from __future__ import annotations

from contextlib import contextmanager
from contextvars import ContextVar
from typing import Iterator, Optional

_llm_call_counter: ContextVar[Optional["PlanningLlmCallCounter"]] = ContextVar(
    "planning_llm_call_counter",
    default=None,
)


class PlanningLlmCallCounter:
    """Anzahl erfolgreicher OpenRouter-Chat-Completions in einem Request-Kontext."""

    __slots__ = ("count",)

    def __init__(self) -> None:
        self.count = 0

    def record(self, amount: int = 1) -> None:
        try:
            n = int(amount)
        except (TypeError, ValueError):
            n = 1
        if n > 0:
            self.count += n


def current_planning_llm_call_counter() -> Optional[PlanningLlmCallCounter]:
    return _llm_call_counter.get()


def record_planning_llm_call(amount: int = 1) -> None:
    counter = _llm_call_counter.get()
    if counter is not None:
        counter.record(amount)


@contextmanager
def planning_llm_call_meter() -> Iterator[PlanningLlmCallCounter]:
    """Aktiviert LLM-Zählung für den umschlossenen Block (inkl. verschachtelter Aufrufe)."""
    counter = PlanningLlmCallCounter()
    token = _llm_call_counter.set(counter)
    try:
        yield counter
    finally:
        _llm_call_counter.reset(token)


__all__ = [
    "PlanningLlmCallCounter",
    "current_planning_llm_call_counter",
    "planning_llm_call_meter",
    "record_planning_llm_call",
]