---------------------------------------------------------------------------
-- @author Espen Wiborg <espenhw@grumblesmurf.org>
-- @author Julien Danjou <julien@danjou.info>
-- @copyright 2008 Espen Wiborg, Julien Danjou
-- @release v3.1-rc3-14-gc7ee83f
-- 
-- note: rewritten by Perry Hargrave perry)dot(hargrave)at(gmail.com
-- note: this is a version of revelation.lua modified for awesome 3.2-50
--
---------------------------------------------------------------------------
local math = math
local table = table
local pairs = pairs
local button = button
local awful = awful
local capi =
{
  tag = tag,
  client = client,
  keygrabber = keygrabber,
  mouse = mouse,
  screen = screen
}
local print = print
--- Exposé implementation
module("revelation")
 
function clients(class, s)
  local clients
  if class then
    clients = {}
    for k, c in pairs(capi.client.get(s)) do
      if c.class == class then
        table.insert(clients, c)
      end
    end
  else
    clients = capi.client.get(s)
  end
  return clients
end
 
function selectfn(restore)
  return function(c)
    restore()
    -- Pop to client tag
    awful.tag.viewonly(c:tags()[1])
    -- Focus and raise
    capi.client.focus = c
    c:raise()
  end
end
 
--- Returns keyboardhandler.
-- Arrow keys move focus, Return selects, Escape cancels.
-- Ignores modifiers.
function keyboardhandler (restore)
  return function (mod, key, event)
    if event ~= "press" then return true end
    -- translate vim-style home keys to directions
    if key == "j" or key == "k" or key == "h" or key == "l" then
      if key == "j" then
        key = "Down"
      elseif key == "k" then
        key = "Up"
      elseif key == "h" then
        key = "Left"
      elseif key == "l" then
        key = "Right"
      end
    end
 
    --
    if key == "Escape" then
      restore()
      -- awful.tag.history.restore()
      return false
    elseif key == "Return" then
      selectfn(restore)(capi.client.focus)
      return false
    elseif key == "Left" or key == "Right" or
      key == "Up" or key == "Down" then
      awful.client.focus.bydirection(key:lower())
    end
    return true
  end
end
 
--- Implement Exposé (from Mac OS X).
-- @param class The class of clients to expose, or nil for all clients.
-- @param fn A binary function f(t, n) to set the layout for tag t for n clients, or nil for the default layout.
-- @param s The screen to consider clients of, or nil for "current screen".
function revelation(class, fn, s)
  local scr = s or capi.mouse.screen
  local t = awful.tag.selected()
 
  local oset = {}
  oset.mwfact = awful.tag.getmwfact(t)
  oset.ncol = awful.tag.getncol(t)
  oset.nmaster = awful.tag.getnmaster(t)
  oset.layout = awful.tag.getproperty(t,"layout")
 
  awful.tag.setproperty(t,"layout",awful.layout.suit.fair )
  awful.tag.viewmore( capi.screen[scr]:tags() )
 
  awful.hooks.user.call("arrange", scr)
 
  local function restore()
    local t = awful.tag.selected()
  
    awful.tag.setproperty(t,"layout",oset.layout)
    awful.tag.setnmaster(oset.nmaster,t)
    awful.tag.setmwfact(oset.mwfact, t)
    awful.tag.setncol(oset.ncol, t)
    awful.tag.viewonly(t)
 
    capi.keygrabber.stop()
  end
 
  capi.keygrabber.run(keyboardhandler(restore))
end