#!/usr/bin/env python3
"""Run unit tests and enforce a maximum execution-time budget.

Usage:
  python3 scripts/check_test_speed.py [--max-seconds N]
"""

from __future__ import annotations

import re
import subprocess  # nosec B404

import click

from gitea_runner_manager.i18n import _

DEFAULT_MAX_SECONDS = 2.0
TEST_COMMAND = ["make", "test-unit"]
_TIMING_RE = re.compile(r"(\d+) passed.* in ([0-9.]+)s")


def run_tests() -> tuple[str, str]:
    """Execute the unit-test suite and return (stdout, stderr)."""
    result = subprocess.run(  # nosec B603
        TEST_COMMAND,
        capture_output=True,
        text=True,
        check=False,
    )
    return result.stdout, result.stderr


def parse_duration(output: str) -> float:
    """Extract elapsed seconds from pytest summary line.

    Raises:
        click.ClickException: when the timing line cannot be found.
    """
    for line in output.splitlines():
        match = _TIMING_RE.search(line)
        if match:
            return float(match.group(2))
    raise click.ClickException(_("Could not parse test execution time from output."))


def check_speed(duration: float, max_seconds: float) -> None:
    """Validate duration is within budget; raise on violation."""
    if duration > max_seconds:
        raise click.ClickException(
            _(
                "Unit tests too slow: {duration:.2f}s (max allowed: {max}s).\n"
                "  Fix: run 'make pytest-cov' to profile, then optimise slow tests.\n"
                "  Hint: avoid unnecessary imports, use lighter mocks, or cache fixtures.",
                duration=duration,
                max=max_seconds,
            )
        )


def main(max_seconds: float) -> None:
    """Run tests, parse timing, and enforce the budget."""
    stdout, stderr = run_tests()
    combined = stdout + "\n" + stderr
    click.echo(combined, err=False)

    duration = parse_duration(combined)
    check_speed(duration, max_seconds)
    click.echo(
        _(
            "Unit tests passed in {duration:.2f}s (under {max}s limit).",
            duration=duration,
            max=max_seconds,
        )
    )


@click.command()
@click.option(
    "--max-seconds",
    type=float,
    default=DEFAULT_MAX_SECONDS,
    show_default=True,
    help="Maximum allowed execution time in seconds.",
)
def cli(max_seconds: float) -> None:
    main(max_seconds)


if __name__ == "__main__":  # pragma: no cover
    cli()  # pragma: no cover