#!/usr/bin/env python
# -*- coding: utf-8 -*-
import time
import sys
import logging
import smtplib
import socket 
import signal
import ConfigParser
from datetime import datetime
from email import encoders
from email.header import Header
from email.mime.text import MIMEText
from email.utils import parseaddr, formataddr

CONF_PATH = "/etc/zabbix/alarm_email.conf"
logging.basicConfig(level=logging.INFO,
          format='%(asctime)s [%(levelname)s]: %(message)s',
          filename='/var/log/zabbix/send_alarm_email.log')
class EmailObject:
  def __init__(self,to_addr,content):
    self.timeout = 10
    self.retry = 3
    self.cp = self._parse_config()
    self.cpl = self._parse_config().sections()
    self.conf = dict(self.cp.items(self.cpl[0])) 
    # common how to use one
    self.to_addr = to_addr
    self.content = content
  # get ConfigParser,for section selection
  def _parse_config(self):
    cp = ConfigParser.ConfigParser()
    cp.read(CONF_PATH)
    return cp
  # set base config
  def _conf_parse(self):
    self.subject = "zabbix告警"
    self.from_addr = self.conf["from_addr"]
    self.password = self.conf["password"]
    self.smtp_server = self.conf["smtp_server"]
  def _msg_parse(self):
    #msg = self.content.split("*")
    #state = "alarm" if msg[0] == "PROBLEM" else "ok"
    #severity = msg[1]
    #head_time = map(int,msg[2].split("."))
    #tail_time = map(int,msg[3].split(":"))
    ## if not host?
    #event_type = "host." + msg[4]
    #reason = msg[5].replace("_"," ")
    #alarm_id = int(msg[6])
    #message = msg
    return self.content
  def _change_server(self):
    # if len = 1 and this fun is called,means that all servers hava been tried
    if(len(self.cpl) > 1):
      self.cpl.pop(0)
      self.retry = 3
      self.conf = dict(self.cp.items(self.cpl[0]))
      logging.info("Change server to {}".format(self.cpl[0]))
      self.send_email()
    else:
      logging.warning("No server could be used,try to config more server(now is {}) or increase the timeout [{}]!".format(self.cp.sections(),self.timeout))
      exit()
 
  def send_email(self):
    # signal handle  
    def handler(signum,frame):
      if self.retry > 0:
        raise AssertionError
      else:
        self._change_server()
    self._conf_parse()
    from_addr = self.from_addr 
    password = self.password
    smtp_server = self.smtp_server
    timeout = self.timeout
    to_addr = self.to_addr
    msg = MIMEText(self.content,'plain','utf-8')
    msg['Subject'] = Header(self.subject, 'utf-8')
    msg['From'] = 'AlarmEmail'+'<'+from_addr+'>'  
    msg['To'] = "******@******.com"
    
    try:
      signal.signal(signal.SIGALRM,handler)
      signal.alarm(timeout)
      server = smtplib.SMTP_SSL(smtp_server,465)
      server.login(from_addr, password)
      server.sendmail(from_addr,to_addr, msg.as_string())
      logging.info("Send email successfully!From:[{}],To:[{}],Content:[{}]".format(from_addr,to_addr,self.content))
      server.quit()
      exit()
    except AssertionError:
      self.retry -= 1
      logging.info("Begin to resend email for the {}th times".format(3-self.retry))
      self.send_email()
    except smtplib.SMTPAuthenticationError,e:
      logging.error("Server [{}] authentication failed".format(smtp_server))
      self._change_server()
'''
example:
from emailtest import emailtest

eb = emailtest.EmailObject("******@******.com","test content")
eb.send_email()
tips:
increase timeout:
  eb.timeout = 10
increase retry times:
  eb.retry = 5
'''