#!/usr/bin/python
#
# Author: Sergei Franco (sergei at sergei.nz)
# License: GPL3 
# Warranty: NONE! Use at your own risk!
# Disclaimer: I am no programmer!
# Description: this script will sync two IMAP mailboxes.
#


import imaplib
import ConfigParser
import os
import time
import sys
import re

sleep_time=15
config_file='imap2imap.conf'
mid_r=re.compile('Message-ID:\s<(.*)>.*')
date_r=re.compile('\d+\s\(INTERNALDATE\s\"(.*)\"\)')

def config_sample():
    print(
"""
Sample config:

[source]
hostname=outlook.office365.com
username=microsoftsucks@example.com
password=hunter12
trash=Deleted Items
#movetotrash=yes
#delete=yes

[destination]
hostname=imap.gmail.com
username=dontbeevil@gmail.com
password=hunter12

""")

def config():
    global config_file
    conf = {'source':{},'destination':{}}
    c = ConfigParser.ConfigParser()
    try:
        c.read([os.path.expanduser(config_file)])
    except Exception as e:
        print("Unable to read config file! Error: %s" % str(e))
        config_sample()
        sys.exit(1)
    try:
        conf['source'].update({'server' : c.get('source', 'hostname')})
        conf['source'].update({'username' : c.get('source', 'username')})
        conf['source'].update({'password' : c.get('source', 'password')})

        try:
            conf['source'].update({'trash' : c.get('source', 'trash')})
        except ConfigParser.NoOptionError:
            conf['source'].update({'trash' : 'Trash'})

        try:
            conf['source'].update({'inbox' : c.get('source', 'inbox')})
        except ConfigParser.NoOptionError:
            conf['source'].update({'inbox': 'INBOX'})

        try:
            delete = c.get('source', 'delete')
            if delete.lower() == 'true' or delete.lower() == 'yes':
                conf['source'].update({'delete' : True })
            else:
                conf['source'].update({'delete' : False })
        except ConfigParser.NoOptionError:
            conf['source'].update({'delete': False})

        try:
            delete = c.get('source', 'movetotrash')
            if delete.lower() == 'true' or delete.lower() == 'yes':
                conf['source'].update({'movetotrash' : True })
            else:
                conf['source'].update({'movetotrash' : False })
        except ConfigParser.NoOptionError:
            conf['source'].update({'movetotrash': False})

        conf['destination'].update({'server' : c.get('destination', 'hostname')})
        conf['destination'].update({'username' : c.get('destination', 'username')})
        conf['destination'].update({'password' : c.get('destination', 'password')})

        try:
            conf['destination'].update({'inbox' : c.get('destination', 'inbox')})
        except ConfigParser.NoOptionError:
            conf['destination'].update({'inbox': 'INBOX'})

    except Exception as e:
        print("Unable to get a config item! Error: %s" % str(e))
        config_sample()
        sys.exit(1)
    return conf


def connect(conf):
    try:
        s_h = conf['source']['server']
        s_u = conf['source']['username']
        s_p = conf['source']['password']
        d_h = conf['destination']['server']
        d_u = conf['destination']['username']
        d_p = conf['destination']['password']
    except Exception as e:
        print("Bad config! Error: %s",str(e))
    try:
        print("Connecting to (source) %s" % s_h)
        src = imaplib.IMAP4_SSL(s_h)
        print("Logging in as (source) %s" % s_u)
        src.login(s_u, s_p)
        print("Connecting to (destination) %s" % d_h)
        dst = imaplib.IMAP4_SSL(d_h)
        print("Logging in as (destination) %s" % d_u)
        dst.login(d_u, d_p)
    except Exception as e:
        print("Unable to connect! Error: %s" % str(e))

    return src,dst

def delete_message(con,message_id):
    print("Deleting message id %s" % message_id)
    try:
        r, res = con.store(message_id, '+FLAGS', '(\\Deleted)')
        if r != 'OK':
            print("Failed to delete message id %s; response: %s, %s" % (message_id,r,res))
        return False
    except Exception as e:
        print("Failed to delete message id %s; Error: %s" % (message_id,str(e)))
        return False

def expunge(con):
    try:
        r, res = con.expunge()
        if r != 'OK':
            print("Failed to expunge mailbox; response: %s, %s" % (r,res))
        return False
    except Exception as e:
        print("Failed to expunge mailbox; Error: %s" % str(e))
    return True

def copy_message(con,message_id,directory):
    print("Copying message id %s to '%s'" % (message_id, directory))
    try:
        r, res = con.copy(message_id,trash)

        if r != 'OK':
            print("Failed to copy message id %s to '%s'; response: %s, %s" % (message_id,directory,r,res))
        return False
    except Exception as e:
        print("Failed to copy message id %s to '%s'; Error: %s" % (message_id,directory,str(e)))
        return False

    return True

def date_message(con,message_id):
    global date_r
    try:
        r, res = con.fetch(message_id, '(INTERNALDATE)')
        date = date_r.match(res[0]).group(1)
        if r != 'OK':
            print("Failed to get INTERNALDATE of message id %s, Falling back to 'NOW'; response: %s, %s" % (message_id,r,res))
        return time.time()
    except Exception as e:
        print("Failed to get INTERNALDATE of message id %s, Falling back to 'NOW'; Error: %s" % (message_id,str(e))) 
        return time.time()
    return date

def find_dupes(src_con,dst_con,message_id):
    global mid_r
    print("Searching for duplicates for message id %s" % message_id)
    try:
        r,res = src_con.fetch(message_id, '(BODY[HEADER.FIELDS (MESSAGE-ID)])')
        if r != 'OK':
            return False
        mid = mid_r.match(res[0][1]).group(1)
        r,[res] = dst_con.search(None,'(HEADER Message-ID "%s")' % mid)
        if res:
            print("Message with Message-ID <%s> is already on the destination. Skipping..." % mid)
            return True
        else:
            return False
    except Exception as e:
        print("Unable to fetch Message-ID for message id %s" % message_id)
        return False
        
conf = config()
src_inbox = conf['source']['inbox']
dst_inbox = conf['destination']['inbox']
trash = conf['source']['trash']
delete = conf['source']['delete']
movetotrash = conf['source']['movetotrash']


while True:
    try:
        src_con,dst_con = connect(conf)
        src_con.select(src_inbox)
        dst_con.select(dst_inbox)
        sys.stdout.flush()
        r, [message_ids] = src_con.search(None, 'ALL')
        message_ids = message_ids.split()
        message_count = len(message_ids)
        print("Found %d messages in '%s'" % (message_count,src_inbox))
        for message_id in message_ids:
            print("Fetching message id %s" % message_id)
            r, data = src_con.fetch(message_id, '(RFC822)')
            date_message(src_con,message_id)

            if not find_dupes(src_con,dst_con,message_id):
                print("Uploading message id %s" % message_id)
                r, res = dst_con.append(dst_inbox, '', imaplib.Time2Internaldate(date_message(src_con,message_id)), str(''.join(data[0][1])))
            else:
                r = 'OK' #not ideal
            if r == 'OK':
                if movetotrash:
                    print("Moving message id %s to '%s'" % (message_id, trash))
                    if copy_message(src_con,message_id,trash):
                        delete_message(src_con,message_id)
                elif delete:
                    delete_message(src_con,message_id)

            else:
                print("Failed to upload message id %s; response %s, %s" % (message_id,r,res))
            sys.stdout.flush()
        expunge(src_con)
        print("Finished all (%d) messages, sleeping for %d seconds" % (message_count,sleep_time))
        time.sleep(sleep_time)

    except Exception as e:
        print("Error: %s" % str(e))
    finally:
        src_con.close()
        src_con.logout()
        dst_con.close()
        dst_con.logout()