import json
import logging
from io import StringIO

import structlog
from opentelemetry.trace import NonRecordingSpan, SpanContext, TraceFlags, use_span

from app.runtime.logging import configure_logging


def test_application_log_is_serialized_as_json() -> None:
    stream = StringIO()

    configure_logging(stream=stream)

    logging.getLogger("app.test").info("application_event")

    payload = json.loads(stream.getvalue().splitlines()[0])

    assert payload["event"] == "application_event"
    assert payload["level"] == "info"
    assert payload["logger"] == "app.test"
    assert isinstance(payload["timestamp"], str)

    _reset_logging()


def test_structured_context_is_preserved_and_rendered_in_event() -> None:
    stream = StringIO()

    configure_logging(stream=stream)

    structlog.get_logger("app.test").warning(
        "application_event",
        order_uuid="order-1",
        attempt=2,
        retryable=True,
        details={"code": "invalid"},
    )

    payload = json.loads(stream.getvalue().splitlines()[0])

    assert payload["event"] == (
        'application_event attempt=2 details={"code":"invalid"} '
        'order_uuid="order-1" retryable=true'
    )
    assert payload["order_uuid"] == "order-1"
    assert payload["attempt"] == 2
    assert payload["retryable"] is True
    assert payload["details"] == {"code": "invalid"}

    _reset_logging()


def test_active_open_telemetry_context_is_added_to_structured_log() -> None:
    stream = StringIO()
    span_context = SpanContext(
        trace_id=0x1234567890ABCDEF1234567890ABCDEF,
        span_id=0x1234567890ABCDEF,
        is_remote=False,
        trace_flags=TraceFlags(TraceFlags.SAMPLED),
    )

    configure_logging(stream=stream)

    with use_span(NonRecordingSpan(span_context)):
        structlog.get_logger("app.test").info("application_event")

    payload = json.loads(stream.getvalue().splitlines()[0])

    assert payload["trace_id"] == "1234567890abcdef1234567890abcdef"
    assert payload["span_id"] == "1234567890abcdef"
    assert payload["trace_flags"] == 1
    assert payload["event"] == (
        'application_event span_id="1234567890abcdef" trace_flags=1 '
        'trace_id="1234567890abcdef1234567890abcdef"'
    )

    _reset_logging()


def test_missing_open_telemetry_context_is_not_added_to_log() -> None:
    stream = StringIO()

    configure_logging(stream=stream)

    structlog.get_logger("app.test").info("application_event")

    payload = json.loads(stream.getvalue().splitlines()[0])

    assert "trace_id" not in payload
    assert "span_id" not in payload
    assert "trace_flags" not in payload

    _reset_logging()


def test_active_open_telemetry_context_is_added_to_stdlib_log() -> None:
    stream = StringIO()
    span_context = SpanContext(
        trace_id=0x1234567890ABCDEF1234567890ABCDEF,
        span_id=0x1234567890ABCDEF,
        is_remote=False,
        trace_flags=TraceFlags(TraceFlags.SAMPLED),
    )

    configure_logging(stream=stream)

    with use_span(NonRecordingSpan(span_context)):
        logging.getLogger("app.test").info("application_event")

    payload = json.loads(stream.getvalue().splitlines()[0])

    assert payload["trace_id"] == "1234567890abcdef1234567890abcdef"
    assert payload["span_id"] == "1234567890abcdef"
    assert payload["trace_flags"] == 1

    _reset_logging()


def test_uvicorn_loggers_use_shared_json_logging_setup() -> None:
    stream = StringIO()

    configure_logging(stream=stream)

    logging.getLogger("uvicorn.error").error("uvicorn_error_event")
    logging.getLogger("uvicorn.access").info("uvicorn_access_event")

    records = [json.loads(line) for line in stream.getvalue().splitlines()]

    assert [record["event"] for record in records] == [
        "uvicorn_error_event",
        "uvicorn_access_event",
    ]
    assert [record["logger"] for record in records] == [
        "uvicorn.error",
        "uvicorn.access",
    ]
    assert all(record["level"] in {"error", "info"} for record in records)
    assert all(isinstance(record["timestamp"], str) for record in records)

    _reset_logging()


def _reset_logging() -> None:
    structlog.reset_defaults()
    root_logger = logging.getLogger()
    root_logger.handlers = []
    for logger_name in ("uvicorn", "uvicorn.error", "uvicorn.access"):
        logging.getLogger(logger_name).handlers = []