import hashlib
import requests
from xml.etree import ElementTree

import langfingaz.util.fileUtil as fileUtil


def requestMeetingData() -> str:
    response = requests.get(getRequestUrl())
    if not response.ok:
        raise ValueError("error during request, got status code {}".format(response.status_code))

    tree = ElementTree.fromstring(response.content)
    if tree.find('returncode').text != 'SUCCESS':
        raise ValueError('error getting API data')

    return str(response.content, encoding=response.encoding)


def getRequestUrl(api_method: str = 'getMeetings', query_string: str = '') -> str:
    url = getUrl()
    api_url = url + "api/"
    secret = getSecret()
    h = hashlib.sha1((api_method + query_string + secret).encode('utf-8'))
    checksum = h.hexdigest()

    if len(query_string) > 0:
        query_string += '&'

    return api_url + api_method + '?' + query_string + 'checksum=' + checksum


def getUrl() -> str:
    filepath = fileUtil.getProjectBaseDir().joinpath("secret").joinpath("url.txt")
    url = fileUtil.readFirstLine(filepath).strip()
    if not url.endswith("/"):
        raise ValueError("url should end with '/'")
    return url


def getSecret() -> str:
    filepath = fileUtil.getProjectBaseDir().joinpath("secret").joinpath("secret.txt")
    secret = fileUtil.readFirstLine(filepath).strip()
    min_length = 12
    if len(secret) <= min_length:
        raise ValueError("secret should be longer than {} characters!".format(min_length))
    return secret