Objects made to keep a list of egos, for possible removal.

Removal is done by rewinding an object and replaying all other egos on
top of it. Not too fancy, but surefire.

game/engines/default/engine/Zone.lua

@@ -467,6 +467,68 @@ local pick_ego = function(self, level, e, eegos, egos_list, type, picked_etype,
 	if egos_list[#egos_list] then print("Picked ego", type.."/"..eegos..":"..etype, ":=>", egos_list[#egos_list].name) else print("Picked ego", type.."/"..eegos..":"..etype, ":=>", #egos_list) end
 end
 
+-- Applies a single ego to a (pre-resolved) entity
+-- May be in need to resolve afterwards
+function _M:applyEgo(e, ego, type)
+	if not e.__original then e.__original = e:clone() end
+	print("ego", ego.__CLASSNAME, ego.name, getmetatable(ego))
+	local orig_ego = ego
+	ego = ego:clone()
+	local newname
+	if ego.prefix then newname = ego.name .. e.name
+	else newname = e.name .. ego.name end
+	print("applying ego", ego.name, "to ", e.name, "::", newname, "///", e.unided_name, ego.unided_name)
+	ego.unided_name = nil
+	ego.__CLASSNAME = nil
+	ego.__ATOMIC = nil
+	-- The ego requested instant resolving before merge ?
+	if ego.instant_resolve then ego:resolve(nil, nil, e) end
+	if ego.instant_resolve == "last" then ego:resolve(nil, true, e) end
+	ego.instant_resolve = nil
+	-- Void the uid, we dont want to erase the base entity's one
+	ego.uid = nil
+	ego.rarity = nil
+	ego.level_range = nil
+	-- Merge according to Object's ego rules.
+	table.ruleMergeAppendAdd(e, ego, self.ego_rules[type] or {})
+	
+	e.name = newname
+	e.egoed = true
+	e.ego_list = e.ego_list or {}
+	e.ego_list[#e.ego_list + 1] = {orig_ego, type}
+end
+
+local function reapplyEgos(e)
+	if not e.__original then return e end
+	local brandNew = e.__original -- it will be cloned upon first ego application
+	if e.ego_list and #e.ego_list > 0 then
+		for _, ego_args in ipairs(e.ego_list) do
+			self:applyEgo(brandNew, unpack(ego_args))
+		end
+	end
+	e:replaceWith(brandNew)
+end
+
+-- Remove an ego
+function _M:removeEgo(e, ego)
+	local idx = nil
+	for i, v in ipairs(e.ego_list or {}) do
+		if v[1] == ego then
+			idx = i
+		end
+	end
+	if not idx then return end
+	table.remove(e.ego_list, idx)
+	reapplyEgos(e)
+	return ego
+end
+
+function _M:removeEgoByName(e, ego_name)
+	for i, v in ipairs(e.ego_list or {}) do
+		if v[1].name == ego_name then return self:removeEgo(e, v) end
+	end
+end
+
 --- Finishes generating an entity
 function _M:finishEntity(level, type, e, ego_filter)
 	e = e:clone()
@@ -480,25 +542,7 @@ function _M:finishEntity(level, type, e, ego_filter)
 
 		if #egos_list > 0 then
 			for ie, ego in ipairs(egos_list) do
-				print("addon", ego.__CLASSNAME, ego.name, getmetatable(ego))
-				ego = ego:clone()
-				local newname
-				if ego.prefix then newname = ego.name .. e.name
-				else newname = e.name .. ego.name end
-				print("applying addon", ego.name, "to ", e.name, "::", newname, "///", e.unided_name, ego.unided_name)
-				ego.unided_name = nil
-				ego.__CLASSNAME = nil
-				ego.__ATOMIC = nil
-				-- The ego requested instant resolving before merge ?
-				if ego.instant_resolve then ego:resolve(nil, nil, e) end
-				if ego.instant_resolve == "last" then ego:resolve(nil, true, e) end
-				ego.instant_resolve = nil
-				-- Void the uid, we dont want to erase the base entity's one
-				ego.uid = nil
-				-- Merge according to Object's ego rules.
-				table.ruleMergeAppendAdd(e, ego, self.ego_rules[type] or {})
-				e.name = newname
-				e.egoed = true
+				self:applyEgo(e, ego, type)
 			end
 			-- Re-resolve with the (possibly) new resolvers
 			e:resolve()
@@ -570,25 +614,7 @@ function _M:finishEntity(level, type, e, ego_filter)
 
 		if #egos_list > 0 then
 			for ie, ego in ipairs(egos_list) do
-				print("ego", ego.__CLASSNAME, ego.name, getmetatable(ego))
-				ego = ego:clone()
-				local newname
-				if ego.prefix then newname = ego.name .. e.name
-				else newname = e.name .. ego.name end
-				print("applying ego", ego.name, "to ", e.name, "::", newname, "///", e.unided_name, ego.unided_name)
-				ego.unided_name = nil
-				ego.__CLASSNAME = nil
-				ego.__ATOMIC = nil
-				-- The ego requested instant resolving before merge ?
-				if ego.instant_resolve then ego:resolve(nil, nil, e) end
-				if ego.instant_resolve == "last" then ego:resolve(nil, true, e) end
-				ego.instant_resolve = nil
-				-- Void the uid, we dont want to erase the base entity's one
-				ego.uid = nil
-				-- Merge according to Object's ego rules.
-				table.ruleMergeAppendAdd(e, ego, self.ego_rules[type] or {})
-				e.name = newname
-				e.egoed = true
+				self:applyEgo(e, ego, type)
 			end
 			-- Re-resolve with the (possibly) new resolvers
 			e:resolve()