core/menusystem: restore keyboard navigation support in grid system

sonic-boost.love/core/modules/menusystem/grid.lua

@@ -59,6 +59,12 @@ function GridBox:getSlotHitbox(slot)
   return x, y, w, h
 end
 
+function GridBox:getSlotCenter(slot)
+  local x, y, w, h = self:getSlotHitbox(slot)
+
+  return x + (w/2), y + (h/2)
+end
+
 function GridBox:getWidgetID(slot)
   local widgetID
   if self.slots[slot] ~= nil then
@@ -109,21 +115,19 @@ function GridBox:keyreleased(key, code)
   slotID = self:getWidgetSlot(self.widget.selected)
   local col, line = self.cursor.x, self.cursor.y
   if key == 'left' then
-    --self:moveCol(-1)
+    self:moveCol(-1)
-    --self:moveCursor(col - 1, line)
   end
 
   if key == 'right' then
-    --self:moveCol(1)
+    self:moveCol(1)
-    --self:moveCursor(col + 1, line)
   end
 
   if key == 'up' then
-    --self:moveCursor(col, line - 1)
+    self:moveLine(-1)
   end
 
   if key == 'down' then
-    --self:moveCursor(col, line + 1)
+    self:moveLine(1)
   end
 
   if key == "A" and self.widget.selected <= #self.widget.list then
@@ -131,6 +135,48 @@ function GridBox:keyreleased(key, code)
   end
 end
 
+function GridBox:moveCol(direction)
+  local orig_x, orig_y = self:getSlotCenter(self.widget.selected)
+  local distance = self.w -- on met directement à la distance max possible le système
+  local nearastWidget = 0
+  for i,v in ipairs(self.slots) do
+    local xx, yy = self:getSlotCenter(i)
+    -- On commence par vérifier si le slot est bien positionné par rapport au
+    -- widget de base
+    if utils.math.sign(xx - orig_x) == direction then
+      if utils.math.pointDistance(orig_x, orig_y, xx, yy) < distance then
+        distance = utils.math.pointDistance(orig_x, orig_y, xx, yy)
+        nearestWidget = v.widgetID
+      end
+    end
+  end
+
+  if nearestWidget ~= 0 then
+    self.widget.selected = nearestWidget
+  end
+end
+
+function GridBox:moveLine(direction)
+  local orig_x, orig_y = self:getSlotCenter(self.widget.selected)
+  local distance = self.h -- on met directement à la distance max possible le système
+  local nearastWidget = 0
+  for i,v in ipairs(self.slots) do
+    local xx, yy = self:getSlotCenter(i)
+    -- On commence par vérifier si le slot est bien positionné par rapport au
+    -- widget de base
+    if utils.math.sign(yy - orig_y) == direction then
+      if utils.math.pointDistance(orig_x, orig_y, xx, yy) < distance then
+        distance = utils.math.pointDistance(orig_x, orig_y, xx, yy)
+        nearestWidget = v.widgetID
+      end
+    end
+  end
+
+  if nearestWidget ~= 0 then
+    self.widget.selected = nearestWidget
+  end
+end
+
 function GridBox:mousemoved(x, y)
   local widgetID = self:getWidgetAtPoint(x, y)