import typing
import base64
from smtplib import SMTPException, SMTPResponseException

from flask import Markup
from flask_mail import Message

from core_notifications.extensions import mail, celery
from core_notifications.helpers.common import split_long_lines, replace_urls
from core_notifications.logs import logger
from core_notifications.settings import Settings


@celery.task(
    bind=True,
    default_retry_delay=Settings.TASK_RETRY_DELAY,
    retry_kwargs={"max_retries": Settings.TASK_MAX_RETRIES},
)
def send_email_task(
    self,
    subject: str,
    to: str,
    body: str,
    analytic_url: str,
    analytics: dict,
    cc: typing.Optional[typing.List[str]] = None,
    attachments: typing.Optional[typing.List] = None,
    track_clicks: bool = False,
):
    logger.bind(to=to, subject=subject, cc=cc).info("Sending email")
    if cc:
        cc = cc if isinstance(cc, list) else [cc]

    if track_clicks:
        body = replace_urls(
            body=body,
            email_id=self.request.id,
            to=to,
            analytic_url=analytic_url,
            **analytics,
        )

    # Do all body processing before the splitting the long lines!

    text_body = split_long_lines(
        Markup(body).striptags(), Settings.MAX_LINE_LENGTH
    )
    html_body = split_long_lines(body, Settings.MAX_LINE_LENGTH)

    msg = Message(
        subject=subject,
        recipients=[to],
        body=text_body,
        html=html_body,
        sender=Settings.MAIL_DEFAULT_SENDER,
        extra_headers={
            "X-SES-CONFIGURATION-SET": Settings.MAIL_CONFIGURATION_SET
        },
        cc=cc,
    )

    if attachments:
        for attachment in attachments:
            msg.attach(
                attachment["filename"],
                attachment["filetype"],
                base64.b64decode(attachment["base64_data"]),
            )

    try:
        mail.send(msg)
    except SMTPResponseException as exc:
        # Reaching sending limits (AWS Throttling failure)
        if exc.smtp_code == 454:
            logger.bind(to=to, subject=subject, cc=cc, exc=exc).warning(
                "Reaching sending limits"
            )
            raise self.retry(
                exc=exc, countdown=Settings.TASK_REACHING_LIMITS_RETRY_DELAY
            )
        else:
            raise self.retry(exc=exc)
    except SMTPException as exc:
        raise self.retry(exc=exc)