#!/usr/bin/env python3
"""Observe curl exit codes on a disposable, loopback-only HTTP server."""
import argparse
import json
import platform
import subprocess
import tempfile
import threading
from datetime import datetime, timezone
from http.server import BaseHTTPRequestHandler, ThreadingHTTPServer
from pathlib import Path


class Handler(BaseHTTPRequestHandler):
    def log_message(self, *args):
        pass

    def do_GET(self):
        status, body = (200, b'release-v2') if self.path == '/ok' else (404, b'not-found')
        self.send_response(status)
        self.send_header('Content-Length', str(len(body)))
        self.end_headers()
        self.wfile.write(body)


def main():
    parser = argparse.ArgumentParser()
    parser.add_argument('--output', required=True, type=Path)
    output = parser.parse_args().output
    if output.exists():
        raise SystemExit('Existing evidence will not be overwritten.')
    server = ThreadingHTTPServer(('127.0.0.1', 0), Handler)
    worker = threading.Thread(target=server.serve_forever, kwargs={'poll_interval': .05}, daemon=True)
    worker.start()
    observations = []
    try:
        with tempfile.TemporaryDirectory(prefix='punchblog-curl-exit-') as directory:
            for fail in (False, True):
                for path in ('/ok', '/missing'):
                    target = Path(directory) / ('body-' + str(len(observations)))
                    command = ['curl', '--disable', '--noproxy', '*', '-sS', '--connect-timeout', '2', '--max-time', '3',
                               '-o', str(target), '-w', '%{http_code}']
                    if fail:
                        command.append('--fail')
                    result = subprocess.run(command + [f'http://127.0.0.1:{server.server_port}{path}'],
                                            capture_output=True, text=True, timeout=5)
                    observations.append({'path': path, 'fail_option': fail, 'http_status': int(result.stdout),
                                         'curl_exit': result.returncode,
                                         'body': target.read_text() if target.exists() else '', 'stderr': result.stderr.strip()})
    finally:
        server.shutdown()
        server.server_close()
        worker.join(timeout=3)
    assert [(x['http_status'], x['curl_exit']) for x in observations] == [(200, 0), (404, 0), (200, 0), (404, 22)]
    version = subprocess.run(['curl', '--disable', '--version'], capture_output=True, text=True, check=True).stdout.splitlines()[0]
    record = {'schema_version': 1, 'observed_at': datetime.now(timezone.utc).isoformat(),
              'environment': {'python': platform.python_version(), 'os': platform.system(), 'curl': version,
                              'binding': '127.0.0.1:자동 배정 포트'},
              'method': '같은 합성 HTTP 서버의 200·404에 curl을 --fail 유무로 네 번 실행했습니다. 각 요청에 새 출력 파일을 사용했습니다.',
              'limits': '운영 서버·Nginx·CDN·TLS·네트워크 장애를 시험하지 않았습니다. --fail이 모든 인증 오류를 감지한다는 검증도 아닙니다.',
              'observations': observations,
              'tables': {'exits': {'headers': ['요청', '--fail', 'HTTP 상태', 'curl 종료 코드', '저장 본문'],
                                  'rows': [[r['path'], '사용' if r['fail_option'] else '없음', r['http_status'], r['curl_exit'], r['body'] or '없음'] for r in observations]}}}
    output.parent.mkdir(parents=True, exist_ok=True)
    with output.open('x', encoding='utf-8') as stream:
        json.dump(record, stream, ensure_ascii=False, indent=2)
        stream.write('\n')
    print(json.dumps({'cases': len(observations), 'checks': 'passed', 'output': str(output)}))


if __name__ == '__main__':
    main()