"""Unit tests for telemetry after the passive-collection refactor.

The application no longer pushes OTLP. This module verifies that telemetry
setup/shutdown are safe no-ops and that structured logging still reaches the
configured root handler.
"""

from __future__ import annotations

import logging

import pytest

from contract_check.core.logging import configure_logging, get_logger
from contract_check.core.telemetry import get_meter, get_tracer, setup_telemetry, shutdown_telemetry


@pytest.fixture(autouse=True)
def _reset_logging():
    """Configure logging before each test and clean handlers after."""
    configure_logging("INFO", json_output=True, service="test-service", env="test")
    yield
    root = logging.getLogger()
    root.handlers.clear()


def test_setup_telemetry_is_safe_noop() -> None:
    """setup_telemetry() runs without error and does not add an OTLP handler."""
    root = logging.getLogger()
    before = list(root.handlers)

    setup_telemetry("test")
    try:
        after = list(root.handlers)
        # No new handlers are attached because OTLP is no longer initialized.
        assert after == before
    finally:
        shutdown_telemetry()


def test_shutdown_telemetry_is_safe_noop() -> None:
    """shutdown_telemetry() can be called even when setup_telemetry() was skipped."""
    shutdown_telemetry()
    shutdown_telemetry()  # idempotent


def test_otlp_endpoint_env_does_not_initialize_exporters(monkeypatch: pytest.MonkeyPatch) -> None:
    """A legacy OTLP endpoint env var must not cause the application to import OTel SDK."""
    monkeypatch.setenv("OTEL_EXPORTER_OTLP_ENDPOINT", "http://collector:4318")
    from contract_check.core.config import get_settings

    # Settings explicitly ignores unknown env vars, but a stale env var must not
    # be picked up by telemetry code. Refresh the cached settings instance.
    get_settings.cache_clear()

    root = logging.getLogger()
    before = list(root.handlers)
    setup_telemetry("test")
    try:
        after = list(root.handlers)
        assert after == before
        assert not any(type(h).__name__.startswith(("OTLP", "StructlogOTLP")) for h in after)
    finally:
        shutdown_telemetry()
        get_settings.cache_clear()


def test_get_tracer_and_meter_are_safe_noop() -> None:
    """Tracer/meter accessors return objects that do not require OTel SDK."""
    tracer = get_tracer("test")
    meter = get_meter("test")
    # They should be truthy and accept the expected creation calls without raising.
    assert tracer
    assert meter
    span = tracer.start_span("ignored")
    span.end()
    counter = meter.create_counter("ignored")
    counter.add(1)


def test_configure_logging_delivers_events_to_root_stream_handler() -> None:
    """After configure_logging, structlog events propagate to the root StreamHandler."""
    root = logging.getLogger()
    assert any(isinstance(h, logging.StreamHandler) for h in root.handlers)

    log = get_logger("test")
    log.info("smoke_test", answer=42)