moss - MailbOx Search Script
----------------------------

Moss is a tool for searching mailboxes. It is still in experimental stage,
use at your own risk.

Moss is distributed under GPL v3.

Prerequisites
-------------

Moss requires mutt (an mail user agent) to run:

  www.mutt.org

For example, on Ubuntu:

  apt-get install mutt

Usage
-----

I am aware that the following is insufficient. I will enhance one day.

Run the program as follows:

  moss <path-to-mailbox>

where <path-to-mailbox> may be a single-file mbox or a Maildir.

In the program, you can move the selection up and down with 'k' and 'j' keys
(vim style). With 'K' and 'J' you can scroll without moving the selection.
To enter a command, just type (no command starts with any of 'kjKJ', so there
is no clash with the movement keys).

In Moss, you first build a query, which is an expression returning true/false
for any given email message. The query is presented in the form of a tree
which you can build interactively.

Commands:
  null - create a 'NULL' subexpression (a placeholder),
  substring - create a substring expression (finds one string inside
              another)
  and - create a logical 'and' expression or add a sibling to an expression
        inside an 'and'
  or - create a logical 'or' expression or add a sibling to an expression
       inside an 'or'
  forall [<type>] - create a universal quantifier over a variable of the
                    type given ('string'/'int'/'att'; 'att' means attachment),
                    default type is 'string'
  exists [<type>] - create an existential quantifier over a variable of the
                    type given ('string'/'int'/'att'; 'att' means attachment)
                    default type is 'string'
  const - creates a constant
  var - creates a variable
  header - creates an expression evaluating to the value of the given email
           header
  att - creates an expression evaluating to the list of all attachments of
        the email (except the attachments of mime types 'text/*'),
  attsize - creates an expression evaluating to the size of the attachment
            given as argument (returns 0 for multipart),
  gt - creates a 'greater' comparison expression on int arguments
  more - add a sibling to a list of expressions (in and/or and quantifiers),
  mod - change the parameter value (for elements that have parameters),
  search - search using the current query,
  show - show search results (this creates a temporary mailbox and opens
         with mutt),
  quit - exit the application.

Besides, hitting <return> on an element which has a parameter works as 'mod'.