from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
from email.utils import make_msgid
from imaplib import IMAP4, IMAP4_PORT
from smtplib import SMTP, SMTP_PORT
from subprocess import call
from textwrap import dedent
from time import sleep


class AutoReplyer:
    refresh_delay = 5

    imap_server = None
    imap_port = IMAP4_PORT
    imap_user = None
    imap_password = None

    smtp_server = None
    smtp_port = SMTP_PORT
    smtp_user = None
    smtp_password = None

    from_address = None
    body = None
    body_html = None

    def __init__(self):
        self.imap = IMAP4(self.imap_server, self.imap_port)
        self.imap.login(self.imap_user, self.imap_password)
        self.smtp = SMTP(self.smtp_server, self.smtp_port)
        self.smtp.login(self.smtp_user, self.smtp_password)

    def close(self):
        self.smtp.close()
        self.imap.logout()

    def create_auto_reply(self, original):
        mail = MIMEMultipart('alternative')
        mail['Message-ID'] = make_msgid()
        mail['References'] = mail['In-Reply-To'] = original['Message-ID']
        mail['Subject'] = 'Re: ' + original['Subject']
        mail['From'] = self.from_address
        mail['To'] = original['Reply-To'] or original['From']
        mail.attach(MIMEText(dedent(self.body), 'plain'))
        mail.attach(MIMEText(self.body_html, 'html'))
        return mail

    def send_auto_reply(self, original):
        self.smtp.sendmail(
            self.from_address, [original['From']],
            self.create_auto_reply(original).as_bytes())
        log = 'Replied to “%s” for the mail “%s”' % (original['From'],
                                                     original['Subject'])
        print(log)
        try:
            call(['notify-send', log])
        except FileNotFoundError:
            pass

    def reply(self, mail_number):
        self.imap.select(readonly=True)
        _, data = self.imap.fetch(mail_number, '(RFC822)')
        self.imap.close()
        self.send_auto_reply(email.message_from_bytes(data[0][1]))
        self.imap.select(readonly=False)
        self.imap.store(mail_number, '+FLAGS', '\\Answered')
        self.imap.close()

    def check_mails(self):
        self.imap.select(readonly=False)
        _, data = self.imap.search(None, '(UNSEEN UNANSWERED)')
        self.imap.close()
        for mail_number in data[0].split():
            self.reply(mail_number)

    def run(self):
        try:
            while True:
                self.check_mails()
                sleep(self.refresh_delay)
        finally:
            self.close()