Remember mouse position per screen

The mouse position is saved and restored when focusing another screen

If the target screen has no saved mouse position, the relative position
of the current screen is used

Signed-off-by: lesell_b <lesell_b@epitech.eu>

lib/awful/screen.lua

@@ -24,6 +24,8 @@ local screen = {}
 local data = {}
 data.padding = {}
 
+mouse_per_screen = {}
+
 ---
 -- Return Xinerama screen number corresponding to the given (pixel) coordinates.
 -- The number returned can be used as an index into the global
@@ -44,8 +46,8 @@ function screen.getbycoord(x, y, default)
     return default
 end
 
---- Give the focus to a screen, and move pointer.
+--- Give the focus to a screen, and move pointer to last known position on this
--- Keeps relative position of the pointer on the screen.
+-- screen, or keep position relative to the current focused screen
 -- @param _screen Screen number (defaults / falls back to mouse.screen).
 function screen.focus(_screen)
     client = client or require("awful.client")
@@ -53,7 +55,11 @@ function screen.focus(_screen)
 
     -- screen and pos for current screen
     local s = capi.mouse.screen
-    local pos = capi.mouse.coords()
+    local pos
+
+    if not mouse_per_screen[s] then
+        -- This is the first time we enter this screen,
+        mouse_per_screen[s] = capi.mouse.coords()
 
         -- keep relative mouse position on the new screen
         local relx = (pos.x - capi.screen[s].geometry.x) / capi.screen[s].geometry.width
@@ -61,6 +67,10 @@ function screen.focus(_screen)
 
         pos.x = capi.screen[_screen].geometry.x + relx * capi.screen[_screen].geometry.width
         pos.y = capi.screen[_screen].geometry.y + rely * capi.screen[_screen].geometry.height
+    else
+        -- restore mouse position
+        pos = mouse_per_screen[s]
+    end
 
    -- move cursor without triggering signals mouse::enter and mouse::leave
     capi.mouse.coords(pos, true)
@@ -71,7 +81,8 @@ function screen.focus(_screen)
     end
 end
 
---- Give the focus to a screen, and move pointer, by physical position relative to current screen.
+--- Give the focus to a screen, and move pointer to last known position on this
+-- screen, or keep position relative to the current focused screen
 -- @param dir The direction, can be either "up", "down", "left" or "right".
 -- @param _screen Screen number.
 function screen.focus_bydirection(dir, _screen)
@@ -88,8 +99,8 @@ function screen.focus_bydirection(dir, _screen)
     end
 end
 
---- Give the focus to a screen, and move pointer, but relative to the current
+--- Give the focus to a screen, and move pointer to last known position on this
--- focused screen.
+-- screen, or keep position relative to the current focused screen
 -- @param i Value to add to the current focused screen index. 1 will focus next
 -- screen, -1 would focus the previous one.
 function screen.focus_relative(i)