"""
NLProxy SDK test runner CLI.

This command runs the SDK test suite using pytest and supports class-level
and flow/marker-based filtering so tests can be executed in a scalable,
reproducible way.

Examples:
  python -m nlproxy tests
  python -m nlproxy tests --class TestPromptShield
  python -m nlproxy tests --flow unit
  python -m nlproxy tests --flow integration --pytest-args="-v --maxfail=1"

The runner defaults to `tests.py` in the project root and delegates to the
Python interpreter environment that executes the CLI.
"""

from __future__ import annotations

import argparse
import shlex
import subprocess
import sys
from typing import List, Optional


def create_parser() -> argparse.ArgumentParser:
    parser = argparse.ArgumentParser(
        prog="nlproxy tests",
        description="Run NLProxy SDK tests with optional class or flow filtering.",
        formatter_class=argparse.RawDescriptionHelpFormatter,
        epilog="""
Examples:
  python -m nlproxy tests
  python -m nlproxy tests --class TestPromptShield
  python -m nlproxy tests --flow unit
  python -m nlproxy tests --flow integration --pytest-args='-v --maxfail=1'
        """,
    )

    parser.add_argument(
        "-c",
        "--class",
        dest="test_class",
        help="Run only a single test class or filter expression from tests.py",
    )
    parser.add_argument(
        "-f",
        "--flow",
        dest="flow",
        help="Run tests by pytest marker/flow name (e.g. unit, integration, performance, asyncio)",
    )
    parser.add_argument(
        "--path",
        type=str,
        default="tests.py",
        help="Path to the test module or directory to execute",
    )
    parser.add_argument(
        "--pytest-args",
        type=str,
        default="",
        help="Additional pytest arguments to pass through",
    )
    parser.add_argument(
        "-q",
        "--quiet",
        action="store_true",
        help="Suppress output from the test runner when possible",
    )

    return parser


def build_pytest_args(args: argparse.Namespace) -> List[str]:
    pytest_args: List[str] = [sys.executable, "-m", "pytest", args.path]

    if args.test_class:
        pytest_args.extend(["-k", args.test_class])

    if args.flow:
        pytest_args.extend(["-m", args.flow])

    if args.pytest_args:
        pytest_args.extend(shlex.split(args.pytest_args))

    if args.quiet:
        pytest_args.append("-q")

    return pytest_args


def cmd_tests(args: argparse.Namespace) -> int:
    pytest_args = build_pytest_args(args)
    print(f"Running tests: {' '.join(pytest_args)}")

    result = subprocess.run(pytest_args, env=sys.environ.copy())
    return result.returncode


def main(argv: Optional[List[str]] = None) -> int:
    parser = create_parser()
    args = parser.parse_args(argv)
    try:
        return cmd_tests(args)
    except KeyboardInterrupt:
        print("Test execution interrupted by user.", file=sys.stderr)
        return 130
    except FileNotFoundError as exc:
        print(f"Test runner failed: {exc}", file=sys.stderr)
        return 1
    except Exception as exc:
        print(f"Unexpected error while running tests: {exc}", file=sys.stderr)
        return 1


if __name__ == "__main__":
    raise SystemExit(main())