big ass modding update

src/ui/Screens.lua

@@ -0,0 +1,71 @@
+-- Screen id -> factory resolution.  The screens registry (Data.screens)
+-- wins; engine screens are the require fallback, so a mod-free boot
+-- resolves every id to the exact module it required before.  One cache,
+-- dropped with the rest of the asset caches on dev-mode hot reload.
+
+local Assets = require("src.render.Assets")
+local Logger = require("src.core.Logger")
+
+local Screens = {}
+
+-- ids whose builtin module is not under src/ui/
+local BUILTIN = {
+  ManagerState = "src.mods.ManagerState",
+}
+
+local cache = {}
+
+local function builtinFor(id)
+  return require(BUILTIN[id] or ("src.ui." .. id))
+end
+
+local function resolve(game, id)
+  local hit = cache[id]
+  if hit then return hit end
+  local screens = game and game.data and game.data.screens
+  local record = screens and screens[id]
+  local factory
+  if record then
+    -- registry record: { new = fn } or a bare function (05-registry-system)
+    factory = (type(record) == "function") and { new = record } or record
+    factory.__modOwned = true
+  else
+    factory = builtinFor(id)
+  end
+  cache[id] = factory
+  return factory
+end
+
+function Screens.get(game, id)
+  return resolve(game, id)
+end
+
+function Screens.push(game, id, ...)
+  local factory = resolve(game, id)
+  local inst
+  if factory.__modOwned then
+    -- a broken mod screen degrades to the builtin, never a dead end
+    local ok, result = pcall(factory.new, game, ...)
+    if ok and result then
+      inst = result
+    else
+      Logger.error("mod screen '%s' failed: %s -- using builtin",
+                   id, tostring(result))
+      cache[id] = nil
+      inst = builtinFor(id).new(game, ...)
+    end
+  else
+    inst = factory.new(game, ...)
+  end
+  inst.screenId = inst.screenId or id
+  game.stack:push(inst)
+  return inst
+end
+
+function Screens.invalidate()
+  cache = {}
+end
+
+Assets.register(Screens.invalidate)
+
+return Screens