Redshift widget and icons added

widgets/contrib/redshift.lua

@@ -0,0 +1,79 @@
+
+--[[
+                                                   
+     Licensed under GNU General Public License v2  
+      * (c) 2014, blueluke <http://github.com/blueluke>
+                                                   
+--]]
+
+local os = os
+local awful = require("awful")
+local spawn = awful.util.spawn_with_shell
+
+local setmetatable = setmetatable
+
+-- redshift
+-- lain.widgets.contrib.redshift
+local redshift = {}
+
+local attached = false                       -- true if attached to a widget
+local active = false                         -- true if redshift is active            
+local running = false                        -- true if redshift was initialized 
+local update_fnct = function() end           -- function that is run each time redshift is toggled. See redshift:attach().
+
+
+local function init()
+    -- As there is no way to determine if redshift was previously
+    -- toggled off (i.e Awesome on-the-fly restart), kill redshift to make sure
+    os.execute("pkill redshift")
+    -- Remove existing color adjustment
+    spawn("redshift -x")
+    -- (Re)start redshift
+    spawn("redshift")
+    running = true
+    active = true
+end
+
+function redshift:toggle()
+    if running then 
+        -- Sending -USR1 toggles redshift (See project website)
+        os.execute("pkill -USR1 redshift")
+        active = not active
+    else 
+        init()
+    end
+    update_fnct()
+end
+
+function redshift:off()
+    if running and active then
+        redshift:toggle()
+    end
+end
+
+function redshift:on()
+    if not active then
+        redshift:toggle()
+    end
+end
+
+function redshift:is_active()
+    return active
+end
+
+-- Attach to a widget
+-- Provides a button which toggles redshift on/off on click
+-- @ param widget:  widget to attach to
+-- @ param fnct:  function to be run each time redshift is toggled (optional).
+--                         Use it to update widget text or icons on status change.
+function redshift:attach(widget, fnct)
+    update_fnct  = fnct or function() end
+    if not attached then
+        init()
+        attached = true
+        update_fnct()
+    end
+    widget:buttons(awful.util.table.join( awful.button({}, 1, function () redshift:toggle() end) ))
+end
+
+return setmetatable(redshift, { _call = function(_, ...) return create(...) end })