Translation system first draft

state/State.lua

@@ -6,6 +6,7 @@ local ScopeStack = require("state.ScopeStack")
 local tag_manager = require("state.tag_manager")
 local event_manager = require("state.event_manager")
 local resumable_manager = require("state.resumable_manager")
+local translation_manager = require("state.translation_manager")
 local uuid = require("common").uuid
 local parser = require("parser")
 local binser = require("lib.binser")
@@ -32,6 +33,7 @@ State = class {
 			event_manager:setup(self)
 			tag_manager:setup(self)
 			resumable_manager:setup(self)
+			translation_manager:setup(self)
 		end
 	end,
 

state/translation_manager.lua

@@ -0,0 +1,78 @@
+local class = require("class")
+
+local ast = require("ast")
+local Table, Identifier
+
+local translations_identifier, translations_symbol
+
+local translation_manager = class {
+	init = false,
+
+	setup = function(self, state)
+		state.scope:define(translations_symbol, Table:new(state))
+	end,
+
+	-- context is the context Struct - when translating, the translation will only be used for nodes that at least match this context
+	-- original is the original node (non-evaluated)
+	-- translated is the translated node (non-evaluated)
+	set = function(self, state, context, original, translated)
+		local translations = state.scope:get(translations_identifier)
+		if not translations:has(state, original) then
+			translations:set(state, original, Table:new(state))
+		end
+		local tr = translations:get(state, original)
+		return tr:set(state, context, translated)
+	end,
+
+	-- context is the context Struct of the calling translation
+	-- original is the original node to translate (non-evaluated)
+	-- returns the (evaluated) translated node, or the original node if no translation defined
+	eval = function(self, state, context, original)
+		local translations = state.scope:get(translations_identifier)
+		if translations:has(state, original) then
+			local tr = translations:get(state, original)
+
+			-- find most specific translation
+			local translated, specificity = nil, -1
+			for match_context, match_translated in tr:iter(state) do
+				local matched, match_specificity = true, 0
+				for key, val in match_context:iter() do
+					if context:has(key) and val:hash() == context:get(key):hash() then
+						match_specificity = match_specificity + 1
+					else
+						matched = false
+						break
+					end
+				end
+				if matched then
+					if match_specificity > specificity then
+						translated, specificity = match_translated, match_specificity
+					elseif match_specificity == specificity then
+						print("a a dà é payé")
+					end
+				end
+			end
+
+			-- found, evaluate translated
+			if translated then
+				-- eval in a scope where all active translations, as translating the translation would be stupid
+				state.scope:push_partial(translations_identifier)
+				state.scope:define(translations_symbol, Table:new(state))
+				local r = translated:eval(state)
+				state.scope:pop()
+				return r
+			end
+		end
+
+		-- no matching translation
+		return original.expression:eval(state)
+	end,
+}
+
+package.loaded[...] = translation_manager
+Table, Identifier = ast.Table, ast.Identifier
+
+translations_identifier = Identifier:new("_translations") -- Table of { Translatable = Table{ Struct context = translated node, ... }, ... }
+translations_symbol = translations_identifier:to_symbol()
+
+return translation_manager