#!/usr/bin/env python
from email.mime.multipart import MIMEMultipart
from email.mime.text import MIMEText
from email import encoders
import smtplib, os

"""
export ENV_EMAIL_SENDER='Chorke Inc<no-reply@chorke.org.bd>';\
export ENV_EMAIL_FROM='Chorke Inc<no-reply@chorke.org.bd>';\
export ENV_EMAIL_TO='Academia<academia@chorke.org.bd>';\
export ENV_EMAIL_SUBJECT='Subject for Debug Email';\
export ENV_EMAIL_BODY='Body for Debug Email';\
\
export ENV_SMTP_USER='no-reply@chorke.org.bd';\
export ENV_SMTP_HOST='mail.chorke.org.bd';\
export ENV_SMTP_PASS='p@$$w0rd';\
export ENV_SMTP_PORT='587';\
export ENV_SMTP_DBUG='1';\
export ENV_SMTP_TTLS='1';\
(curl -s 'https://cdn.chorke.org/exec/cli/python/finology/commons/sendmail.py.txt')|python
"""

class EmailParams:
    def __init__(self):
        env = os.environ
        self.init_parmas(env)

    def init_parmas(self, env):
        self.email_subject = env.get('ENV_EMAIL_SUBJECT', '')
        self.email_sender  = env.get('ENV_EMAIL_SENDER', '')
        self.email_body = env.get('ENV_EMAIL_BODY', '')
        self.email_from = env.get('ENV_EMAIL_FROM', '')
        self.email_to = env.get('ENV_EMAIL_TO', '')
        self.eamil_cc = env.get('ENV_EMAIL_CC', '')

        if bool(self.email_sender) and not(bool(self.email_from)):
            self.email_from = self.email_sender

        if  bool(self.email_from) and not(bool(self.email_sender)):
            self.email_sender = self.email_from

    def print_env(self, debug = False):
        if debug:
            print("ENV_EMAIL_SUBJECT: {0}\nENV_EMAIL_BODY   : [[\n{1}\n]]\n".format(self.email_subject, self.email_body))
            print("ENV_EMAIL_FROM   : {0}\nENV_EMAIL_TO     : {1}\n".format(self.email_from, self.email_to))

class SMTPParams:
    def __init__(self):
        env = os.environ
        self.init_parmas(env)

    def init_parmas(self, env):
        self.smtp_host = env.get('ENV_SMTP_HOST', '')
        self.smtp_port = env.get('ENV_SMTP_PORT', '')
        self.smtp_user = env.get('ENV_SMTP_USER', '')
        self.smtp_pass = env.get('ENV_SMTP_PASS', '')
        self.smtp_ttls = env.get('ENV_SMTP_TTLS', 0)

    def print_env(self, debug = False):
        if debug:
            password = "".ljust(len(self.smtp_user), "*")
            print("ENV_SMTP_USER    : {0}\nENV_SMTP_PASS    : {1}".format(self.smtp_user, password))
            print("ENV_SMTP_HOST    : {0}\nENV_SMTP_PORT    : {1}\nENV_SMTP_TTLS    : {2}\n".format(self.smtp_host, self.smtp_port, self.smtp_ttls))

class SMTPClient:
    def __init__(self, params: SMTPParams):
        self.session = smtplib.SMTP(params.smtp_host, int(params.smtp_port))
        self.session.connect(params.smtp_host, int(params.smtp_port))
        self.session.ehlo()

        if bool(params.smtp_ttls):
            self.session.starttls()
            self.session.ehlo()
        
        self.session.login(params.smtp_user, params.smtp_pass)
        self.session.set_debuglevel(1)
        self.smtp = params

    def send(self, params: EmailParams):
        message = MIMEMultipart()
        message.attach(MIMEText(params.email_body, 'plain'))
        message.add_header('Subject', params.email_subject)
        message.add_header('Reply-To', params.email_sender)
        message.add_header('From', params.email_from)
        message.add_header('To', params.email_to)

        self.session.sendmail(params.email_from, params.email_to, message.as_string())
        self.session.quit()

    @staticmethod
    def print_params(mail: EmailParams, smtp: SMTPParams, debug = False):
        mail.print_env(debug)
        smtp.print_env(debug)

    @staticmethod
    def init(debug = False):
        mail = EmailParams()
        smtp = SMTPParams()

        SMTPClient.print_params(mail, smtp, debug)
        try:
            client = SMTPClient(smtp)
            client.send(mail)
        except Exception as e:
            print("[ERROR]: Email sending failure!\n{0}".format(e))

def main():
    env = os.environ
    debug = bool(env.get('ENV_SMTP_DBUG', 0))
    SMTPClient.init(debug)

if __name__ == "__main__":
    main()