#!/usr/bin/python
#
# Quick mail user agent, usefull for unknown/unconfigured environments.
#
# Performs direct delivery for text message and optional attachment.
#
import os
import sys
import urllib
import smtplib
import string
from email import Encoders
from email.MIMEBase import MIMEBase
from email.MIMEText import MIMEText
from email.MIMEMultipart import MIMEMultipart

class App:

  mail_from = ''
  mail_to = ''
  subject = ''
  attachment = ''
  message = ''
  debug = 0
  smtp_server = 'mail.varkala.net'
  smtp_port = 25

  def __init__( self ):

    self.read_data()
    self.send_data()

  def read_data( self ):

    prompt = self.prompt

    self.mail_from = prompt( 'mail from:' )
    self.mail_to = prompt( 'mail to:' )
    self.subject = prompt( 'subject:' )
    self.attachment = prompt( 'file:' )
    self.message = prompt( 'message:' )

    self.validate_input()

  def prompt( self, msg ):

    return raw_input( msg + ' ' ).strip()

  def validate_input( self ):

    if self.mail_to.find( '@' ) < 0:
      print 'mail to is incorrect!'
      sys.exit( 1 )

    if self.attachment:
      if not ( os.path.isfile( self.attachment ) and os.access( self.attachment, os.R_OK ) ):
        print 'unable to read attachment!'
        opt = self.prompt( 'do you wish to proceed without attachment[y|n]?' ).lower()
        if opt == 'n':
          sys.exit( 1 )
        else:
          self.attachment = ''

  def send_data( self ):

    msg = self.prepare_message()

    # send email
    s = smtplib.SMTP()
    s.set_debuglevel( self.debug )
    s.connect( self.smtp_server, self.smtp_port )
    s.sendmail( self.mail_from, self.mail_to, msg.as_string() )
    s.quit()

    print 'message delivered!'

  def prepare_message( self ):

    msg = MIMEMultipart()
    msg['Subject'] = self.subject
    msg['To'] = self.mail_to
    msg['From'] = self.mail_from
    msg.preamble = "you will not see this in a mime-aware mail reader\n"
    msg.epilogue = ''

    att = MIMEText( self.message )
    msg.attach( att )

    if self.attachment:
      f = open( self.attachment )
      att = MIMEBase( 'application', 'octet-stream' )
      att.set_payload( f.read() )
      Encoders.encode_base64( att )
      att.add_header( 'Content-Disposition', 'attachment', filename=self.get_filename() )
      msg.attach( att )
      f.close()

    return msg

  def get_filename( self ):

    return self.attachment.split( os.sep )[ -1 ]

def main():

  App()

if __name__ == '__main__':

  main()