import json
import logging
import sys
from collections.abc import Iterator
from datetime import UTC, datetime

import pytest

from agentci.observability.logging import JsonFormatter, configure_logging


@pytest.fixture(autouse=True)
def restore_logging_state() -> Iterator[None]:
    root = logging.getLogger()
    original_handlers = root.handlers[:]
    original_level = root.level
    client_levels = {name: logging.getLogger(name).level for name in ("httpx", "httpcore")}
    try:
        yield
    finally:
        root.handlers[:] = original_handlers
        root.setLevel(original_level)
        for name, level in client_levels.items():
            logging.getLogger(name).setLevel(level)


def record(*, message: str = "processed job") -> logging.LogRecord:
    return logging.LogRecord(
        name="agentci.test",
        level=logging.INFO,
        pathname=__file__,
        lineno=1,
        msg=message,
        args=(),
        exc_info=None,
    )


def test_json_formatter_emits_stable_structured_contract() -> None:
    value = record()
    value.__dict__.update(
        operation="worker.execute",
        job_id="job-1",
        duration_ms=0,
        unapproved_secret="not-for-output",
    )

    payload = json.loads(JsonFormatter().format(value))

    assert payload == {
        "timestamp": payload["timestamp"],
        "level": "INFO",
        "logger": "agentci.test",
        "message": "processed job",
        "operation": "worker.execute",
        "job_id": "job-1",
        "duration_ms": 0,
    }
    timestamp = datetime.fromisoformat(payload["timestamp"])
    assert timestamp.tzinfo == UTC


def test_json_formatter_includes_exception_traceback() -> None:
    try:
        raise RuntimeError("provider unavailable")
    except RuntimeError:
        value = record(message="request failed")
        value.exc_info = sys.exc_info()

    payload = json.loads(JsonFormatter().format(value))

    assert payload["message"] == "request failed"
    assert "RuntimeError: provider unavailable" in payload["exception"]


def test_json_formatter_survives_unserializable_context() -> None:
    value = record()
    value.__dict__["operation"] = object()

    payload = json.loads(JsonFormatter().format(value))

    assert payload["level"] == "INFO"
    assert payload["logger"] == "agentci.test"
    assert payload["message"] == "Log record could not be serialized"
    assert "TypeError" in payload["exception"]


def test_repeated_configuration_replaces_handlers_without_duplicate_output(
    capsys: pytest.CaptureFixture[str],
) -> None:
    configure_logging()
    configure_logging()

    root = logging.getLogger()
    assert root.level == logging.INFO
    assert len(root.handlers) == 1
    assert isinstance(root.handlers[0].formatter, JsonFormatter)
    assert logging.getLogger("httpx").level == logging.WARNING
    assert logging.getLogger("httpcore").level == logging.WARNING

    logging.getLogger("agentci.contract").info(
        "configured", extra={"operation": "logging.configure"}
    )
    lines = capsys.readouterr().err.splitlines()
    assert len(lines) == 1
    assert json.loads(lines[0])["operation"] == "logging.configure"