vicious/mboxc.lua

---------------------------------------------------
-- Licensed under the GNU General Public License v2
--  * (c) 2009, Adrian C. <anrxc.sysphere.org>
---------------------------------------------------

-- {{{ Grab environment
local io = { open = io.open }
local setmetatable = setmetatable
local string = { find = string.find }
-- }}}


-- Mboxc: provides the count of total, old and new messages in mbox files
module("vicious.mboxc")


-- {{{ Mbox count widget type
local function worker(format, mbox)
    -- Initialise counters
    local count = {
        old   = 0,
        total = 0,
        new   = 0
    }

    -- Get data from mbox files
    for i=1, #mbox do
        local f = io.open(mbox[i])

        while true do
          -- Read the mbox line by line, if we are going to read some
          -- *HUGE* folders then switch to reading chunks
          local lines = f:read("*line")
          if not lines then break end

          -- Find all messages
          --  * http://www.jwz.org/doc/content-length.html
          local _, from = string.find(lines, "^From[%s]")
          if from ~= nil then count.total = count.total + 1 end

          -- Read messages have the Status header
          local _, status = string.find(lines, "^Status:[%s]RO$")
          if status ~= nil then count.old = count.old + 1 end

          -- Skip the folder internal data
          local _, intdata = string.find(lines, "^Subject:[%s].*FOLDER[%s]INTERNAL[%s]DATA")
          if intdata ~= nil then count.total = count.total - 1 end
        end
        f:close()
    end

    -- Substract total from old to get the new count
    count.new = count.total - count.old

    return {count.total, count.old, count.new}
end
-- }}}

setmetatable(_M, { __call = function(_, ...) return worker(...) end })