import os
from typing import Dict
from typing import Optional

import requests


def get_cloud_file(env, config: Dict[str, str]) -> str:
    """
    Config:
        path (str): the url to download from
        dest (str): file name of the downloaded file
    """

    _path = os.path.join(env.cache_dir, config["dest"])
    if os.path.exists(_path):
        return _path

    url = config["path"]
    response = requests.get(url, stream=True)
    response.raise_for_status()

    with open(_path, 'wb') as f:
        for chunk in response.iter_content(chunk_size=8192):
            if chunk:
                f.write(chunk)

    return _path


def get_vm_file(env, config: Dict[str, str]) -> Optional[str]:
    """
    Config:
        path (str): absolute path on the VM to fetch
        dest (str): file name of the downloaded file
    """

    _path = os.path.join(env.cache_dir, config["dest"])

    file = env.controller.get_file(config["path"])
    if file is None:
        return None
        # raise FileNotFoundError("File not found on VM: {:}".format(config["path"]))
    with open(_path, "wb") as f:
        f.write(file)

    return _path


def get_cache_file(env, config: Dict[str, str]) -> str:
    """
    Config:
        path (str): relative path in cache dir
    """

    _path = os.path.join(env.cache_dir, config["path"])
    assert os.path.exists(_path)
    return _path