import dbm
import shelve

from flask import current_app, g
from flask_login import current_user

from .model.read_mails import QMailAuthuser


def build_qma(username, password):
    authenticator = current_app.config["JWEBMAIL"]["READ_MAILS"]["AUTHENTICATOR"]
    backend = current_app.config["JWEBMAIL"]["READ_MAILS"]["BACKEND"]
    mailbox = current_app.config["JWEBMAIL"]["READ_MAILS"]["MAILBOX"]
    mailbox_user = current_app.config["JWEBMAIL"]["READ_MAILS"]["MAILBOX_USER"]

    return QMailAuthuser(
        username, password, backend, mailbox, mailbox_user, authenticator
    )


def login(username, password):
    return build_qma(username, password).verify_user()


def add_user(user):
    with shelve.open("user_sessions", flag="c") as s:
        s[user.get_id()] = user


def load_user(username):
    try:
        with shelve.open("user_sessions", flag="r") as s:
            user = s[username]
        return user
    except dbm.error:
        return None
    except KeyError:
        return None


def get_read_mails_logged_in():
    if "read_mails" in g:
        return g.read_mails

    with shelve.open("user_sessions", flag="r") as s:
        user_data = s[current_user.get_id()]

    qma = build_qma(current_user.get_id(), user_data.password)
    g.read_mails = qma
    return qma