"""Pytest plugin for integration test profiling.

Adds a ``--profiling-output`` CLI option and hooks into the pytest session
lifecycle to collect endpoint timing data via :class:`EndpointProfiler` and
write a JSON report at the end of the run.

The plugin is automatically loaded by pytest because it lives in the
``tests/integration/`` directory alongside ``conftest.py``.  It registers
a session-scoped ``profiler`` fixture that other fixtures (e.g. the
profiled HTTP clients in conftest.py) can depend on.
"""

from __future__ import annotations

import pytest

from tests.integration.profiler import EndpointProfiler

# ---------------------------------------------------------------------------
# CLI option — registered by root conftest.py to ensure availability
# ---------------------------------------------------------------------------

DEFAULT_PROFILING_OUTPUT = "/tmp/profiling-report.json"


# ---------------------------------------------------------------------------
# Session-scoped profiler instance (shared across all tests)
# ---------------------------------------------------------------------------

# Module-level reference so the session hooks can access it without fixtures.
_profiler: EndpointProfiler | None = None


@pytest.fixture(scope="session")
def profiler() -> EndpointProfiler:
    """Session-scoped :class:`EndpointProfiler` instance.

    Collects timing data across all integration tests.  The summary is
    printed and written to disk by the ``pytest_sessionfinish`` and
    ``pytest_terminal_summary`` hooks below.
    """
    global _profiler  # noqa: PLW0603
    _profiler = EndpointProfiler()
    return _profiler


# ---------------------------------------------------------------------------
# Session hooks — write report + print summary
# ---------------------------------------------------------------------------


def pytest_sessionfinish(session: pytest.Session, exitstatus: int) -> None:
    """Write the profiling JSON report after all tests complete."""
    if _profiler is None:
        return

    output_path = session.config.getoption("profiling_output", DEFAULT_PROFILING_OUTPUT)
    try:
        _profiler.write_json(output_path)
    except OSError:
        # Best-effort — don't fail the session if we can't write the report
        pass


def pytest_terminal_summary(
    terminalreporter: pytest.TerminalReporter,
    exitstatus: int,
    config: pytest.Config,
) -> None:
    """Print the profiling summary table at the end of the test session."""
    if _profiler is None:
        return

    output_path = config.getoption("profiling_output", DEFAULT_PROFILING_OUTPUT)

    terminalreporter.section("Profiling Summary")
    _profiler.print_summary()
    terminalreporter.write_line(f"JSON report written to: {output_path}")