import os
import subprocess
import sys
import traceback

import servicemanager
import win32event
import win32service
import win32serviceutil


SERVICE_NAME = "InventeraServer"
SERVICE_DISPLAY_NAME = "Inventera Server"


def _application_directory():
    executable = sys.executable if getattr(sys, "frozen", False) else __file__
    return os.path.dirname(os.path.abspath(executable))


class InventeraWindowsService(win32serviceutil.ServiceFramework):
    _svc_name_ = SERVICE_NAME
    _svc_display_name_ = SERVICE_DISPLAY_NAME
    _svc_description_ = (
        "Автоматически запускает веб-сервер Inventera при старте Windows."
    )

    def __init__(self, args):
        super().__init__(args)
        self.stop_event = win32event.CreateEvent(None, 0, 0, None)
        self.server_process = None

    def SvcStop(self):
        self.ReportServiceStatus(win32service.SERVICE_STOP_PENDING)
        win32event.SetEvent(self.stop_event)
        self._stop_server()

    def SvcDoRun(self):
        servicemanager.LogInfoMsg("Служба Inventera запускается.")
        try:
            self._run_server()
        except Exception:
            servicemanager.LogErrorMsg(
                "Служба Inventera завершилась с ошибкой:\n"
                + traceback.format_exc()
            )
            raise
        finally:
            self._stop_server()
            servicemanager.LogInfoMsg("Служба Inventera остановлена.")

    def _run_server(self):
        application_directory = _application_directory()
        server_path = os.path.join(application_directory, "Inventera.Server.exe")
        if not os.path.isfile(server_path):
            raise FileNotFoundError(f"Не найден сервер Inventera: {server_path}")

        creation_flags = getattr(subprocess, "CREATE_NO_WINDOW", 0)
        self.server_process = subprocess.Popen(
            [server_path],
            cwd=application_directory,
            creationflags=creation_flags,
        )

        while self.server_process.poll() is None:
            wait_result = win32event.WaitForSingleObject(self.stop_event, 1000)
            if wait_result == win32event.WAIT_OBJECT_0:
                return

        exit_code = self.server_process.returncode
        self.server_process = None
        raise RuntimeError(
            "Inventera.Server.exe неожиданно завершился "
            f"с кодом {exit_code}."
        )

    def _stop_server(self):
        process = self.server_process
        if process is None or process.poll() is not None:
            self.server_process = None
            return

        process.terminate()
        try:
            process.wait(timeout=15)
        except subprocess.TimeoutExpired:
            process.kill()
            process.wait(timeout=5)
        finally:
            self.server_process = None


if __name__ == "__main__":
    win32serviceutil.HandleCommandLine(InventeraWindowsService)