'''
restore-mail-inject.py - Tool to inject mails via IMAP

Copyright (c) 2012 Intra2net AG
'''

import sys
import socket, imaplib
import re
import logging

MAILBOX_RESP = re.compile(r'\((?P<flags>.*?)\) "(?P<delimiter>.*)" (?P<name>.*)')
UIDVAL_RESP = re.compile(r'(?P<name>.*) \(UIDVALIDITY (?P<uidval>.*)\)')
ACLS_RESP = re.compile(b'(?P<user>.*) (?P<acls>.*)')

class MailIterator:
    """This class communicates with the e-mail server."""

    # class attributes
    # IMAP4_SSL for connection with an IMAP server
    mail_con = None
    # list of tuples (uidvalidity, mailboxname) for the retrieved mailboxes
    mailboxes = None
    # logged in status
    logged_in = None

    def __init__(self, username):
        """Creates a connection and a user session."""

        # connect to server
        try:
            self.mail_con = imaplib.IMAP4("intranator.m.i2n")
            # MODIFIED
            imap_socket = socket.socket(socket.AF_UNIX)
            imap_socket.connect("/var/imap/socket/imap")
            self.mail_con.sock = imap_socket
            self.mail_con.file = self.mail_con.sock.makefile('rb')
            logging.info("Connected to mail server.")
        except (self.mail_con.error, socket.error) as ex:
            logging.error("Could not connect to host: %s" % (ex))
            sys.exit()

        # log in
        try:
            self.mail_con.login("cyrus", "geheim")
            self.logged_in = True
            #self.mail_con.proxyauth(username)
            logging.info("Logged in as %s." % username)
        except self.mail_con.error as ex:
            self.logged_in = False
            logging.error("Could not log in as user %s: %s" % (username, ex))
            sys.exit()

        # list mailboxes
        try:
            _result, mailboxes = self.mail_con.list()
        except self.mail_con.error as ex:
            logging.warning("Could not retrieve mailboxes for user %s: %s" % (username, ex))
        self.mailboxes = []
        for mailbox in mailboxes:
            mailbox = MAILBOX_RESP.match(mailbox.decode('iso-8859-1')).groups()
            self.mailboxes.append(mailbox)
        self.mailboxes = sorted(self.mailboxes, key=lambda box: box[2], reverse=True)

        return

    def __del__(self):
        """Closes the connection and the user session."""
        #if self.logged_in:
        #    self.mail_con.close()
        #    self.mail_con.logout()

    def clear_inbox_acls(self, user):
        """Resets the inbox acls for a given user."""
        try:
            _result, inbox_acls = self.mail_con.getacl("INBOX")
        except self.mail_con.error as ex:
            logging.warning("Could not get the acls of INBOX: %s" % ex)
            return
        inbox_acls = ACLS_RESP.findall(inbox_acls[0][6:])
        logging.debug("Retrieved acls from INBOX are %s" % inbox_acls)
        for acl_ref in inbox_acls:
            if acl_ref[0] != user:
                try:
                    self.mail_con.deleteacl("INBOX", acl_ref[0])
                    logging.debug("Reset acls on INBOX for user %s" % acl_ref[0].decode('iso-8859-1'))
                except self.mail_con.error as ex:
                    logging.warning("Could not reset acls on INBOX for user %s: %s" % (acl_ref[0], ex))
        return

    def add_acls(self, mailbox, mailbox_list, original_user, target_user):
        """Add acls to mailbox."""

        # change encoding to internal cyrus format and make folder absolute
        mailbox = mailbox.replace("INBOX/", "user/" + original_user + "/")
        mailbox = mailbox.replace(".", "^")
        mailbox = mailbox.replace("/", ".")

        # find folder to set all acls
        try:
            mbox_acls = mailbox_list[mailbox]
        except KeyError:
            # no rights for the mailbox were found
            return
        for acl_user in mbox_acls:
            if acl_user != target_user and acl_user != original_user:
                try:
                    self.mail_con.setacl(mailbox, acl_user, mbox_acls[acl_user])
                    logging.debug("Set acls %s for user %s on mailbox %s" % (mbox_acls[acl_user], acl_user, mailbox))
                except self.mail_con.error as ex:
                    logging.warning("Could not set acls %s for user %s on mailbox %s: %s" % (mbox_acls[acl_user], acl_user, mailbox, ex))    

        return

    def delete_mailboxes(self, deleted_mailbox):
        """Delete specified mailbox or empty inbox."""
        for mailbox in self.mailboxes:
            pattern = '^\"?' + deleted_mailbox
            # if INBOX it cannot be deleted so add delimiter
            if (deleted_mailbox == "INBOX"):
                pattern += mailbox[1]
            if re.compile(pattern).match(mailbox[2]):
                result, data = self.mail_con.delete(mailbox[2])
                if result == "OK":
                    logging.debug("Deleted mailbox %s" % mailbox[2])
                else:
                    logging.warning("Could not delete mailbox %s: %s" % (mailbox[2], data[0]))         
        return

    def create_mailbox(self, mailbox):
        """Create new mailbox to inject messages."""
        if mailbox != "INBOX":
            result, data = self.mail_con.create(mailbox)
            if result == "OK":
                logging.debug("Creating mailbox %s" % mailbox)
            else:
                logging.warning("Could not create mailbox %s: %s" % (mailbox, data[0]))
        return

    def inject_message(self, message, mailbox, internal_date):
        """Inject a message into a mailbox."""
        result, data = self.mail_con.append(mailbox, "\\Seen", internal_date, message.encode())
        if result == "OK":
            logging.debug("Appending message to mailbox %s" % mailbox)
        else:
            logging.warning("Could not append the e-mail %s: %s" % (message, data[0]))
        return