"""APIClient - Agent — Lightweight HTTP mock server."""
import threading
from http.server import BaseHTTPRequestHandler, HTTPServer

from app.core import storage


_server_instance: HTTPServer | None = None
_server_thread:   threading.Thread | None = None
_server_port:     int = 8888


class _MockHandler(BaseHTTPRequestHandler):
    """Queries the DB on every request so new/edited endpoints are served immediately."""

    def log_message(self, fmt, *args):
        pass  # suppress default console logging

    def _handle(self):
        endpoints = storage.get_mock_endpoints()
        matched = None
        for ep in endpoints:
            method_match = ep.method == "*" or ep.method == self.command
            if method_match and ep.path == self.path:
                matched = ep
                break

        if matched:
            self.send_response(matched.status_code)
            for k, v in matched.response_headers.items():
                self.send_header(k, v)
            body = matched.response_body.encode("utf-8")
            self.send_header("Content-Length", str(len(body)))
            self.end_headers()
            self.wfile.write(body)
        else:
            body = b'{"error": "No mock endpoint matched"}'
            self.send_response(404)
            self.send_header("Content-Type", "application/json")
            self.send_header("Content-Length", str(len(body)))
            self.end_headers()
            self.wfile.write(body)

    do_GET     = _handle
    do_POST    = _handle
    do_PUT     = _handle
    do_PATCH   = _handle
    do_DELETE  = _handle
    do_HEAD    = _handle
    do_OPTIONS = _handle


def start(port: int = 8888) -> str:
    global _server_instance, _server_thread, _server_port
    if _server_instance:
        return f"Already running on port {_server_port}"
    _server_port = port
    try:
        _server_instance = HTTPServer(("localhost", port), _MockHandler)
    except OSError as e:
        return f"Failed to start: {e}"
    _server_thread = threading.Thread(target=_server_instance.serve_forever, daemon=True)
    _server_thread.start()
    return f"Mock server running on http://localhost:{port}"


def stop() -> str:
    global _server_instance, _server_thread
    if _server_instance:
        _server_instance.shutdown()
        _server_instance = None
        _server_thread   = None
        return "Mock server stopped"
    return "Not running"


def is_running() -> bool:
    return _server_instance is not None


def get_port() -> int:
    return _server_port