#!/usr/bin/python

import os
import time
import sys
import re
import smtplib
from email.MIMEText import MIMEText
from email.Utils import formatdate

INTERVAL = 1.0

def readline(filepath):
    fp = open(filepath, "r")
    stat = os.stat(filepath)
    size = stat[6]
    fp.seek(size)
    
    try:
        while True:
            where = fp.tell()
            line = fp.readline()
            if not line:
                time.sleep(INTERVAL)
                fp.seek(where)
            else:
                yield line
    except KeyboardInterrupt, e:
        pass
    except Exception, e:
        print(e)
    finally:
        fp.close()


def create_message(from_addr, to_addr, subject, body):
    msg = MIMEText(body)
    msg["subject"] = subject
    msg["From"] = from_addr
    msg["To"] = to_addr
    msg["Date"] = formatdate()
    
    return msg

def send_mail(server, from_addr, to_addr, message):
    smtp = smtplib.SMTP(server)
    smtp.sendmail(from_addr, [to_addr], message.as_string())
    smtp.close()


def printUsage():
    print(sys.argv[0] + " filepath regex_pattern smtp_server, sendto, subject")


def run():
    if len(sys.argv) != 6:
        printUsage()
        return

    filepath = sys.argv[1]
    pattern = re.compile(sys.argv[2])
    smtp_server = sys.argv[3]
    from_addr = to_addr = sys.argv[4]
    subject = sys.argv[5]

    for line in readline(filepath):
        if pattern.findall(line):
            message = create_message(from_addr, to_addr, subject, line)
            send_mail(smtp_server, from_addr, to_addr, message)
            print line,



if __name__ == "__main__":
    run()