Implement maximize/restore controls

Remove also resize from top and right of the window

data/core/titleview.lua

@@ -3,10 +3,18 @@ local common = require "core.common"
 local style = require "core.style"
 local View = require "core.view"
 
+local restore_command = {
+  symbol = "w", action = function() system.set_window_mode("normal") end
+}
+
+local maximize_command = {
+  symbol = "W", action = function() system.set_window_mode("maximized") end
+}
+
 local title_commands = {
   {symbol = "_", action = function() system.set_window_mode("minimized") end},
-  {symbol = "w", action = function() system.set_window_mode("maximized") end},
-  {symbol = "W", action = function() core.quit() end},
+  maximize_command,
+  {symbol = "X", action = function() core.quit() end},
 }
 
 local TitleView = View:extend()
@@ -28,6 +36,8 @@ function TitleView:update()
     self.size.y = 0
   end
   TitleView.super.update(self)
+  local window_mode = system.get_window_mode()
+  title_commands[2] = window_mode == "maximized" and restore_command or maximize_command
   local title_height = self.size.y
   if core.window_borderless and title_height ~= core.hit_test_title_height then
     local icon_w = style.icon_font:get_width("_")