[FocusManager] correct cursor keys in RTL (#13362)

frontend/ui/widget/focusmanager.lua

@@ -1,9 +1,10 @@
-local bit = require("bit")
+local BD = require("ui/bidi")
 local Device = require("device")
 local Event = require("ui/event")
 local InputContainer = require("ui/widget/container/inputcontainer")
-local logger = require("logger")
 local UIManager = require("ui/uimanager")
+local bit = require("bit")
+local logger = require("logger")
 local util = require("util")
 --[[
 Wrapper Widget that manages focus for a whole dialog
@@ -156,6 +157,7 @@ function FocusManager:onFocusHalfMove(args)
         end
     elseif direction == "left" then
         dx = - math.floor(#row / 2)
+        if BD.mirroredUILayout() then dx = -dx end
         if dx == 0 then
             dx = -1
         elseif dx + x <= 0 then
@@ -163,12 +165,19 @@ function FocusManager:onFocusHalfMove(args)
         end
     elseif direction == "right" then
         dx = math.floor(#row / 2)
+        if BD.mirroredUILayout() then dx = -dx end
         if dx == 0 then
             dx = 1
         elseif dx + x > #row then
-            dx = #row - y -- last column
+            dx = #row - x -- last column
         end
     end
+    if dx ~= 0 and BD.mirroredUILayout() then
+        -- When in RTL we mirror horizontally the elements/buttons on the screen, however we don't mirror self.layout
+        -- therefore we must account for this when moving the focus. Since we're already inverting dx in the FocusMove
+        -- method, we need to "unfix" our value here, before calling onFocusMove, where it will be flipped again.
+        dx = -dx
+    end
     return self:onFocusMove({dx, dy})
 end
 
@@ -214,6 +223,13 @@ function FocusManager:onFocusMove(args)
     end
     local dx, dy = unpack(args)
 
+    -- Flip horizontal direction in RTL mode
+    if dx ~= 0 and BD.mirroredUILayout() then
+        -- When in RTL we mirror horizontally the elements/buttons on the screen, however we don't mirror self.layout
+        -- therefore we must account for this when moving the focus.
+        dx = -dx
+    end
+
     if (dx ~= 0 and not self.movement_allowed.x)
         or (dy ~= 0 and not self.movement_allowed.y) then
         return true