rc: add a systray widget showing desktops with urgent windows

2 files changed, 152 insertions, 1 deletions

diff --git a/rc.lua b/rc.lua
index e1d23c2..d479ca5 100644
--- a/rc.lua
+++ b/rc.lua
@@ -12,6 +12,7 @@ local naughty = require("naughty")
 local bindings   = require("bindings")
 local commondefs = require("commondefs")
 local pager      = require("pager")
+local urgent_wgt = require("urgent_wgt")
 local utils      = require("utils")
 local workspace  = require("workspace")
 
@@ -97,8 +98,11 @@ awful.screen.connect_for_each_screen(function(s)
                       awful.button({ }, 5, function () awful.layout.inc(layouts, -1) end)))
     local layoutbox_container = wibox.container.constraint(layoutbox, 'max', beautiful.xresources.apply_dpi(tray_icon_size))
 
-    local layout_utils = wibox.layout.flex.horizontal()
+    local u_wgt = urgent_wgt.UrgentWidget:new()
+
+    local layout_utils = wibox.layout.fixed.horizontal()
     layout_utils:add(layoutbox_container)
+    layout_utils:add(u_wgt.widget)
 
     -- Create a tasklist widget
     local pgr = pager.Pager:new(wsp, s)
diff --git a/urgent_wgt.lua b/urgent_wgt.lua
new file mode 100644
index 0000000..1b2f60c
--- /dev/null
+++ b/urgent_wgt.lua
@@ -0,0 +1,147 @@
+local awful     = require("awful")
+local beautiful = require("beautiful")
+local shape     = require("gears.shape")
+local wibox     = require("wibox")
+
+local M = {}
+
+local function client_get_desk_idx(c)
+    if c.first_tag then
+        local desk_idx = tonumber('0x' .. c.first_tag.name:sub(1, 2))
+        if desk_idx ~= nil and desk_idx >= 0 then
+            return desk_idx
+        else
+            print('cannot get desk idx: ' .. c.first_tag.name)
+        end
+    end
+    return false
+end
+
+local function urgent_widget_create(name)
+    local textbox = wibox.widget.textbox(' ' .. name .. ' ')
+    local cont_bg = wibox.container.background(textbox)
+    cont_bg.bg = beautiful.bg_urgent
+    cont_bg.fg = beautiful.fg_urgent
+
+    cont_bg:set_shape(shape.rounded_rect, 5)
+    cont_bg.shape_border_width = 1
+    cont_bg.shape_border_color = beautiful.border_focus
+
+    return cont_bg
+end
+
+local UrgentWidget = {}
+
+function UrgentWidget:_desk_client_add(desk_idx, c)
+    -- create the client list, if it does not exist already
+    if self._desktops[desk_idx] == nil then
+        self._desktops[desk_idx] = {}
+    end
+
+    self._desktops[desk_idx][c] = true
+
+    if self._desktop_widgets[desk_idx] == nil then
+        self._desktop_widgets[desk_idx] = urgent_widget_create(desk_idx)
+    end
+
+    for k, w in pairs(self._layout:get_children()) do
+        if w == self._desktop_widgets[desk_idx] then
+            return
+        end
+    end
+    self._layout:add(self._desktop_widgets[desk_idx])
+end
+
+function UrgentWidget:_desk_client_remove(desk_idx, c)
+    self._desktops[desk_idx][c] = nil
+
+    -- remove the widget if there are no clients left
+    local count = 0
+    for c, v in pairs(self._desktops[desk_idx]) do
+        if v then
+            count = count + 1
+        end
+    end
+    if count == 0 then
+        self._layout:remove_widgets(self._desktop_widgets[desk_idx])
+    end
+end
+
+function UrgentWidget:_client_remove(c)
+    if self._clients[c] then
+        self:_desk_client_remove(self._clients[c], c)
+    end
+    self._clients[c] = nil
+end
+
+function UrgentWidget:_client_add(c)
+    local desk_idx   = client_get_desk_idx(c)
+    self._clients[c] = desk_idx
+
+    if desk_idx then
+        self:_desk_client_add(desk_idx, c)
+    end
+
+    -- handle client state changes:
+    -- lose the urgency flag
+    c:connect_signal('property::urgent',
+        function (c)
+            if not c.urgent then
+                self:_client_remove(c)
+            end
+        end)
+    -- client destroyed
+    c:connect_signal('unmanage',
+        function (c)
+            self:_client_remove(c)
+        end)
+    -- client moved
+    c:connect_signal('untagged',
+        function(c, t)
+            local desk_idx = self._clients[c]
+            if desk_idx then
+                self:_desk_client_remove(desk_idx, c)
+            end
+            self._clients[c] = false
+        end)
+    c:connect_signal('tagged',
+        function(c, t)
+            local desk_idx   = client_get_desk_idx(c)
+            self._clients[c] = desk_idx
+
+            if desk_idx then
+                self:_desk_client_add(desk_idx, c)
+            end
+        end)
+end
+
+function UrgentWidget:new()
+    local ret = setmetatable({}, self)
+    self.__index = self
+
+    ret._layout = wibox.layout.fixed.horizontal()
+    ret.widget  = awful.widget.only_on_screen(ret._layout, "primary")
+
+    -- maps from clients to their desk num (or false, when no desk num
+    -- can be determined)
+    ret._clients  = {}
+    -- contains a table of urgent clients per each desktop number
+    ret._desktops = {}
+    ret._desktop_widgets = {}
+
+    -- signal handler for adding new clients
+    client.connect_signal('property::urgent',
+        function (c)
+            -- only do something when urgency flag is on
+            if c.urgent then
+                ret:_client_add(c)
+            end
+        end)
+
+    return ret
+end
+
+M.UrgentWidget = UrgentWidget
+
+return M
+