# -*- coding: utf-8 -*-

import sys
import os
import smtplib
import imaplib
import email
import base64
import re

from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText

class Mailer(object):
    """
        Replies to emails on yandex
    """

    __answer_html = ""
    __answer_text = ""
    __imap_server = "imap.yandex.ru"
    __imap_port = 993
    __smtp_server = "smtp.yandex.ru"
    __smtp_port = 465
    __mail_user = ""
    __mail_password = ""
    __from_filter = ""
    __filter_subject = ""

    __my_name = ""
    __subject_text = "Reply"

    def load_answer(self, filename):
        """ Loads answer template from file"""
        f = open(filename, "r")
        try:
            self.__answer_html = '\n'.join(f.readlines())
        except:
            print("Answer data not found!\n")
        f.close()

    def set_answer_text(self, text_answer):
        """ Not really needed, in case html is not supported"""
        self.__answer_text = text_answer

    def get_unread_emails(self):
        """ Reads emails, fetches user data with regexps """
        conn = imaplib.IMAP4_SSL(self.__imap_server, self.__imap_port)
        result = []

        try:
            print("Connecting to server...")
            (retcode, capabilities) = conn.login(self.__mail_user, self.__mail_password)
        except:
            print("Connect to mail server failed")
            return

        if retcode != 'OK':
            print("Connect failed")
            return

        conn.select() # Select inbox or default namespace
        (retcode, messages) = conn.search(None, '(UNSEEN)', '(FROM "%s")' % self.__from_filter)
        if retcode == 'OK':
            i = 0
            letters = messages[0].split()
            print("%i new letters, processing" % len(letters))
            print(40 * '-')
            for num in letters:
                i += 1
                print('Processing : %i letter...' % i)

                typ, data = conn.fetch(num, '(UID BODY[TEXT])') #'(RFC822)'

                for response_part in data:
                    if isinstance(response_part, tuple):
                        original = email.message_from_bytes(response_part[1])

                        try:
                            body = str(base64.b64decode(original.as_string()))
                        except:
                            body = original.as_string()

                        first_name = re.search('First_name: .*?<', body).group()[12:-1]
                        last_name = re.search('Last_name: .*?<', body).group()[11:-1]
                        user_email = re.search('mailto:.*?"', body).group()[7:]

                        result.append({
                            "first_name" : first_name,
                            "last_name"  : last_name,
                            "email"      : user_email
                        })

                        ret, msg = conn.store(num,'+FLAGS','\\Seen')

                        if ret == 'OK':
                            print(ret, '\t%i read successfully' % i, '\n', 30 * '-')

        conn.close()
        return result

    def send_answers(self, user_data):
        """ Sends answers by template"""
        mail = smtplib.SMTP_SSL(self.__smtp_server, self.__smtp_port)

        try:
            print("Connecting to server before sending...")
            mail.login(self.__mail_user, self.__mail_password)
        except:
            print("Connect to mail server failed")
            return

        print("Started processing answers", '\n', 30 * '-')
        for user in user_data:
            first_name = user["first_name"]
            last_name = user["last_name"]
            user_email = user["email"]
            print("Processing ", first_name, " ", last_name)

            msg = MIMEMultipart('alternative')
            msg['Subject'] = self.__subject_text
            msg['From'] = self.__mail_user
            msg['To'] = user_email

            text =  self.__answer_text.replace("%first_name%", first_name).replace("%last_name%", first_name).replace("%answerer%", self.__my_name)
            html =  self.__answer_html.replace("%first_name%", first_name).replace("%last_name%", first_name).replace("%answerer%", self.__my_name)

            part1 = MIMEText(text, 'plain')
            part2 = MIMEText(html, 'html')

            msg.attach(part1)
            msg.attach(part2)

            try:
                mail.sendmail(self.__mail_user, user_email, msg.as_string())
            except Exception as e:
                print(e)

            print("Done\n", 20 * '-')

        mail.quit()

    def get_answer_body(self):
        return self.__answer_html

    def set_from_filter(self, from_filter):
        self.__from_filter = from_filter

    def set_subject_filter(self, subject_filter):
        self.__subject_filter = subject_filter

    def set_mail_user(self, mail_user):
        self.__mail_user = mail_user

    def set_password(self, password):
        self.__mail_password = password

    def set_my_name(self, my_name):
        self.__my_name = my_name

    def set_subject(self, subject):
        self.__subject_text = subject



if __name__ == '__main__':
    mailer = Mailer()
    mailer.load_answer(os.path.join(os.getcwd(), "answer_ru.html"))
    mailer.set_answer_text("Hello, %username%! \n Have fun \n\n Yours, %receiver%")
    mailer.set_from_filter("sales@radexpro.ru") #replace with yours
    mailer.set_my_name("Polina")                #replace with yours
    mailer.set_mail_user("pb@radexpro.ru")       #replace with yours
    mailer.set_subject("Reply")                 #replace with yours
    mailer.set_password("QweioP12468")            #replace with yours
   # mailer.set_subject_filter("RadExPro")
    # receiving
    print(mailer.get_unread_emails())

    #sending
   # mailer.send_answers([{
   #     "first_name" : "Foo",
   #     "last_name"  : "Bar",
   #     "email"      : "pb@radexpro.ru"
   # }])

    # real usage below
   # mailer.send_answers(mailer.get_unread_emails())