#!/usr/bin/env python3
# -*- coding: utf-8 -*-
'''
Criticality: High
Check that emails can be sent.
'''
import os
import subprocess
import sys
import random
import time
import imp

YELLOW = '\033[93m'
GREEN = '\033[92m'
RED = '\033[91m'
DEF = '\033[0m'

os.chdir(os.path.dirname(__file__))
if not os.path.isfile('../utils.py'):
    print('The envsetup configuration was not found.')
    sys.exit(1)
else:
    es_utils = imp.load_source('es_utils', '../utils.py')
    conf = es_utils.load_conf()


def print_color(txt, col):
    print('%s%s%s' % (col, txt, DEF))


def print_yellow(txt):
    print_color(txt, YELLOW)


def print_red(txt):
    print_color(txt, RED)


def print_green(txt):
    print_color(txt, GREEN)


def check_listening_port():
    # check that postfix listens the port 25 correctly
    status, out = subprocess.getstatusoutput('netstat -pant | grep master | grep 127.0.0.1:25')
    if status != 0:
        print_red('The port 25 is not listened by postfix "master" process.')
        return 1
    else:
        print_green('Postfix is listening port 25 correctly.')
        return 0


def check_relay():
    print('Checking if SMTP relay conforms to conf.')
    status, out = subprocess.getstatusoutput('grep relayhost /etc/postfix/main.cf')
    if status == 0:
        configured_relay = out[len('relayhost'):].strip(' \t=')
    else:
        configured_relay = None
    if not configured_relay:
        # no relay configured, check relayless situations
        ip = conf.get('NETWORK_IP_NAT')
        if not ip:
            ip = conf.get('NETWORK_IP')
        with open('/etc/mailname', 'r') as f:
            d = f.read().strip()
            if d not in ('ubicast.tv', 'ubicast.eu'):
                print_yellow('/etc/mailname does not contain ubicast.eu or ubicast.tv, mails will probably not be received on ubicast mailing lists')
                return 3
            # check spf
            status, output = subprocess.getstatusoutput('host -t TXT ubicast.eu')
            if ip not in output:
                print_red('ip %s is not in ubicast.eu SPF and emails sent from support@ubicast.eu will be treated as spam' % ip)
                return 1
    conf_relay = conf.get('EMAIL_SMTP_SERVER')
    if conf_relay != configured_relay:
        print_red('Configured STMP relay (%s) does not match the expected value (%s).' % (configured_relay, conf_relay))
        return 1
    else:
        print_green('STMP relay is properly set.')
        return 0


def send_test_email():
    email = 'noreply+%s-%s@ubicast.eu' % (time.time(), random.randint(0, 1000))
    print('Sending test email to "%s".' % email)
    cmd = 'echo "This is a test email" | mail -s "Test email from `cat /etc/hostname`" %s' % email
    subprocess.getstatusoutput(cmd)
    time.sleep(3)
    cmd = 'grep "%s" /var/log/mail.log' % email
    status, out = subprocess.getstatusoutput(cmd)
    if status != 0:
        time.sleep(7)
        status, out = subprocess.getstatusoutput(cmd)
        if status != 0:
            print_red('Failed to send email.')
            print('No log entry found using command: %s' % cmd)
            return 1
    if 'bounced' not in out or 'The email account that you tried to reach does not exist.' in out:
        print_green('Email sent.')
        return 0
    else:
        print_red('Failed to send email.')
        print('Sending log line:\n%s' % out)
        return 1


if not os.path.exists('/etc/postfix'):
    print_red('Postfix dir does not exists, please install postfix.')
    sys.exit(1)

rc = check_listening_port()
if rc == 0:
    rc = check_relay()
    if send_test_email() == 1:
        rc = 1

sys.exit(rc)