Roundcube Webmail SieveRules
============================
This plugin adds the ability for users to manage their sieve mail filter rules.
Inspiration and most of the code for this plugin was taken from:
Aleksander Machniak <alec@alec.pl> - original Roundcube managesieve patch
Tested with Dovecot-managesieve

Requirements
============
* Roundcube jQueryUI plugin

Supported Extensions
====================
comparators
envelope
fileinto
imapflags/imap4flags
notify/enotify
regex
reject/ereject
relational
subaddress
vacation
body
copy
spamtest
virustest
variables
date

License
=======
This plugin is released under the GNU General Public License Version 2
(http://www.gnu.org/licenses/gpl-2.0.html).

Even if skins might contain some programming work, they are not considered
as a linked part of the plugin and therefore skins DO NOT fall under the
provisions of the GPL license. See the README file located in the core skins
folder for details on the skin license.

Install
=======
* Place this plugin folder into plugins directory of Roundcube
* Add sieverules to $rcmail_config['plugins'] in your Roundcube config
NB: When downloading the plugin from GitHub you will need to create a directory
called sieverules and place the files in there, ignoring the root directory in
the downloaded archive.

Config
======
The default config file is plugins/sieverules/config.inc.php.dist
Rename this to plugins/sieverules/config.inc.php
* Set the host where managesieve is listening
* Set the port managesieve is listening on
* (Optional) Set the folder delimiter (if your managesieve implementation uses
             a different one to your IMAP server
* Set the name of the ruleset in which your sieve rules are stored
* Enable/disable the actions you want
* (Optional) Define any predefined rules you wish to use
* (Optional) Define a default sieve rule file
* (Optional) Define an example sieve rule file

Predefined rules
================
The predefined rules option allows you specify a set of simple rules which are
available in the UI identified by their name.
All other rule options are hidden when a predefined rule is selected.

The following options are available in each field:

type:
  header
  address
  envelope
  size
operator:
  for rules of type header, address, envelope one of:
    'contains' : contains
    'notcontains' : does not contain
    'is' : is equal to
    'notis' : is not equal to
    'exists' : exists
    'notexists' : does not exist
    'regex' : matches regular expression
    'notregex' : does not match regular expression
    'count "gt"': count is greater than
    'count "ge"': count is greater than or equal to
    'count "lt"': count is less than
    'count "le"': count is less than or equal to
    'count "eq"': count is equal to
    'count "ne"': count does not equal
    'value "gt"': value is greater than
    'value "ge"': value is greater than or equal to
    'value "lt"': value is less than
    'value "le"': value is less than or equal to
    'value "eq"': value is equal to
    'value "ne"': value does not equal
    'user': user part equals
    'notuser': user part does not equal
    'detail': detail part equals
    'notdetail': detail part does not equal
    'domain': domain part equals
    'notdomain': domain part does not equal
  for rules of type size one of:
    'over' : is more than
    'under' : is less than
extra:
  with count or value operators a comparator can be specified, this can be any
  comparator supported by your server (i;ascii-casemap is default, to use this
  comparator the field should be left blank)

The name, header, and target fields do not have set values

Examples:

1) Simple spam filter:
   array(
    'name' => 'Is Spam',
    'type' => 'header',
    'header' => 'X-Spam-Flag',
    'operator' => 'exists',
    'extra' => '',
    'target' => '')

2) Big message filter:
   array(
    'name' => 'Big messages',
    'type' => 'size',
    'header' => '',
    'operator' => 'over',
    'extra' => '',
    'target' => '5M')

3) Spam score filter:
   array(
    'name' => 'Definitely spam',
    'type' => 'header',
    'header' => 'X-Spam-Score',
    'operator' => 'value "ge"',
    'extra' => 'i;ascii-numeric',
    'target' => '10')

Advanced editor
===============
The advanced editor allows users to edit the sieve file directly, without the
restrictions of the UI. Please note any changes made to the file directly which
cannot be parsed by the script will be lost if rules are saved in the normal
mode.

IMPORTANT: There is no validation of the script, please be careful when editing
it directly or you could break all your filtering!

Default sieve rule file
=======================
If a default sieve rule file is specified then when a user has no sieve rules
defined this file is loaded instead and the rules are displayed just as if they
belong to the user. The file can be stored any where on your server and the
user under which your web server runs must have permission to read it.

Example sieve rule file
=======================
If an example sieve rule file is specified then the filters from this script
are loaded and displayed in a drop down in the bottom right of the screen.
Users can select one of these example rules, it will load in the just as one of
their rules, edit it and then save it to their rule set. The file can be stored
any where on your server and the user under which your web server runs must
have permission to read it.

Import existing rulesets
========================
The plugin contains a basic import system and 2 basic import filters. These
example import filters are not perfect, use them with care you may loose some
rule data! You can create your own filter (or modify existing ones), if you do
please consider sharing it. To create an import filter you must add a file in
the importFilters directory. The file must contain a class named
'srimport_[filename]'. Each import filter must have:

 * An attribute called name - this should be the user friendly name of the
   import e.g. `Squirrelmail (Avelsieve)`

 * A pubic function called detector - used to detect of if current rule file
   was genereted with the software

 * A pubic function called importer - converts the rule file to SieveRules
   format

The importer function can return either a string to be parsed by the SieveRules
parser or an array, similar to the one created by the SieveRules parser.

The structure of the rule file
==============================
By default this plugin uses \r\n to seperate lines (RFC 5228) if you want to
use \n instead then set define('RCUBE_SIEVE_NEWLINE', "\n"); in your config.
Add define('RCUBE_SIEVE_INDENT', "\t"); to change the tab character.
By default this plugin places a simple comment at the top of the rule file to
show it was generated by the plugin. This header can be overridden by setting
define('RCUBE_SIEVE_HEADER', "## Generated by Roundcube Webmail SieveRules
Plugin ##"); in your config.

Default values for header, operator and flag drop downs
=======================================================
The default values for these drop downs are set in sieverules.php but they can
be overridden by setting the array in the config for
$rcmail_config['sieverules_default_headers'],
$rcmail_config['sieverules_default_operators'] or
$rcmail_config['sieverules_default_flags'].

sieverules_connect hook
=======================
This hook is triggered right before connecting to the managesieve server and
can be used to change connection details dynamically
Arguments/Return:
  * username - (string) the user's username
  * password - (string) the user's password
  * host - (string) the managesieve host
  * port - (int) the managesieve port
  * auth_type - (string) authentication type (eg. CRAM-MD5, DIGEST-MD5, PLAIN)
  * usetls - (bool) enable TLS for managesieve server connection
  * ruleset - (string) the name of the default ruleset file to be used
  * dir - (string) the path to the plugin directory, use for locating the
    import filters. This is th path to the directory containing the
    importFilters directory
  * elsif - (bool) the rule file can be written as one IF/ELSIF statement or as
    a series of unrelated IF statements
  * auth_cid - (string) optional managesieve authentication identifier to be
    used as authorization proxy
  * auth_pw - (string)  optional managesieve authentication password to be used
    for sieverules_auth_cid

sieverules_save hook
=====================
Before filter information is saved to the managesieve server the plugin hook
sieverules_save is executed, this allows you to perform any custom actions
like updating another system or performing further validation.
Arguments:
  * ruleset - (string) the name of the ruleset file
  * script - (string) the raw sieve script

Return:
  * abort - (boolean) if true the script will not be saved
  * message - (string) optional reason why the script was not saved which
    will be shown to the user