local _screens = {}

--- Registers a new screen definition with the Screen manager.
-- Overwrites existing screen if an ID conflict occurs.
-- @param screen_data table A table containing the screen definition.
--        Must include an `id` field (string).
--        Optional fields:
--        - `situations` (table): A table of situation IDs allowed on this screen. Defaults to an empty table.
--        - `init` (function): Function to execute once when the screen becomes active. Defaults to an empty function.
--        - `update` (function): Function to execute each frame while the screen is active. Defaults to an empty function.
function Screen.register(screen_data)
  if _screens[screen_data.id] then
    trace("Warning: Overwriting screen with id: " .. screen_data.id)
  end
  if not screen_data.situations then
    screen_data.situations = {}
  end
  if not screen_data.init then
    screen_data.init = function() end
  end
  if not screen_data.update then
    screen_data.update = function() end
  end
  _screens[screen_data.id] = screen_data
end

--- Retrieves a registered screen by its ID.
-- @param screen_id string The ID of the screen to retrieve.
-- @return table The screen table, or `nil` if not found.
function Screen.get_by_id(screen_id)
  return _screens[screen_id]
end