# -*- encoding: utf-8 -*-
from contextlib import contextmanager
from datetime import datetime
from email import encoders
from email.mime.base import MIMEBase
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
import logging
import smtplib
import ssl
import typing as T

from latecomers.helpers import retry_and_log, get_date


RETRIES = 3
logger = logging.getLogger(__name__)


class Notifier(object):
    def __init__(
        self,
        smtp_addr: T.Text,
        smtp_port: int,
        smtp_starttls: bool,
        smtp_user: T.Text,
        smtp_pass: T.Text,
        smtp_from: T.Optional[T.Text] = None,
    ) -> None:
        self._starttls = smtp_starttls
        self._addr = smtp_addr
        self._port = smtp_port
        self._user = smtp_user
        self._pass = smtp_pass
        self._from = smtp_from if smtp_from else smtp_user
        logger.info("%s initialized", self)

    @contextmanager
    def connect(self):
        context = ssl.create_default_context()
        if self._starttls:
            with smtplib.SMTP(self._addr, self._port) as conn:
                conn.starttls(context=context)
                conn.login(self._user, self._pass)
                yield conn
        else:
            with smtplib.SMTP_SSL(self._addr, self._port) as conn:
                conn.login(self._user, self._pass)
                yield conn

    def __str__(self) -> T.Text:
        return f"Notifier<{self._addr}:{self._port},from={self._from}>"

    def send(self, to: T.List[T.Text], email: T.Text) -> None:
        with self.connect() as conn:
            conn.sendmail(self._from, to, email)

    @retry_and_log(logger, RETRIES)
    def send_result(
        self, to: T.List[T.Text], cc: T.List[T.Text], result: bytes
    ) -> None:
        date = get_date()
        body = f"Resoconto dei voli dal sito di AdR per l'aereoporto di Ciampino in data {date}"  # noqa: E501

        message = MIMEMultipart()
        message["Date"] = datetime.now().strftime("%a, %d %b %Y %H:%M:%S %z")
        message["From"] = self._from
        message["To"] = ",".join(to)
        if cc:
            message["Cc"] = ",".join(cc)
        message["Subject"] = f"[{date}] Resoconto CIA da AdR"

        message.attach(MIMEText(body, "plain"))

        payload = MIMEBase("application", "octet-stream")
        payload.set_payload(result)
        encoders.encode_base64(payload)
        payload.add_header(
            "Content-Disposition",
            f"attachment; filename={date}.xlsx",
        )

        message.attach(payload)

        email = message.as_string()

        rcpt = to
        rcpt.extend(cc)

        self.send(rcpt, email)

    @retry_and_log(logger, RETRIES)
    def send_no_data(self, to: T.List[T.Text], cc: T.List[T.Text]) -> None:
        date = get_date()
        body = f"""Attenzione

Nessun dato è stato trovato per i voli in data {date} dal sito di AdR per
l'aereoporto di Ciampino. Questo è probabile indice di errore. Contattate
il vostro tecnico preferito.
        """

        message = MIMEMultipart()
        message["Date"] = datetime.now().strftime("%a, %d %b %Y %H:%M:%S %z")
        message["From"] = self._from
        message["To"] = ",".join(to)
        if cc:
            message["Cc"] = ",".join(cc)
        message["Subject"] = f"ATTENZIONE: [{date}] Resoconto CIA da AdR"

        message.attach(MIMEText(body, "plain"))
        email = message.as_string()

        rcpt = to
        rcpt.extend(cc)

        self.send(rcpt, email)