import asyncio
import requests
import json
from typing import List
import os
import configparser


async def write_config_file(
    server_name: str, path_to_template_file: str, path_for_config: str
) -> None:
    template: str = ""
    with open(path_to_template_file, "r") as file:
        template = file.read()

    config_body: str = template.replace("server_name _;", f"server_name {server_name};")
    condifg_full_path: str = os.path.abspath(path_for_config)
    config_filename: str = f"{server_name}.conf"

    if not os.path.isdir(condifg_full_path):
        os.mkdir(condifg_full_path)

    with open(os.path.join(condifg_full_path, config_filename), "w") as file:
        file.write(config_body)


async def send_request(server: str, columns: list, limit: int = 1) -> dict:
    response = requests.get(server, json={"columns": columns, "limit": limit})

    return response.json()


async def get_hosts(server_response: dict) -> List[str]:
    """Получить хосты из ответа сервера.

    Parameters
    ----------
    server_response : dict
    """

    hosts: list = []

    for host in server_response.get("result"):
        hosts.append(host.get("hostname"))

    return hosts


async def read_config(path_to_conf_file: str, section: str = "Main") -> dict:
    """
    Считать конфиг с помощью `configparser`.

    Parameters
    ----------
    path_to_conf_file: str
        Путь к файлу конфига. Можно указывать относительный.

    section: str
        Секция в конфиге, которую нужно считывать. По-умолчанию секция [Main].

    Raises
    ------
    KeyError
        Если в конфиге не найдено указанной секции.

    Returns
    -------
    dict
        Словарь, из значений указанной секции.
    """
    config = configparser.ConfigParser()
    config.read(os.path.abspath(path_to_conf_file))

    if section not in config.sections():
        raise KeyError(f"Section {section} not found in config file!")

    return dict(config.items(section))


async def main():

    cnf = await read_config("service.conf")

    wait_sec: int = int(cnf["frequency_sec"])

    while True:
        resp = await send_request(
            cnf["central_host_url"], columns=["hostname"], limit=9
        )

        hosts = await get_hosts(resp)

        for host in hosts:
            await write_config_file(
                server_name=host,
                path_to_template_file=cnf["template"],
                path_for_config=cnf["path_for_config"],
            )
        await asyncio.sleep(wait_sec)


if __name__ == "__main__":
    asyncio.run(main())