Removable egos

Recently there was a talk on IRC how sweet would it be to be able to strip egos from an object. This achieves just that, keeping a list of egos at each object, too! As a nice bonus, it showcases its capabilities by converting Imbue Item and Reshape Weapon/Armor to slap egos onto objects (and in the second case, to strip them from objects, too). Randarts now have egos, too, and even randart stat powers are hoarded together by the name and converted into egos. Overall it's pretty sweet. Of course, this is not limited to objects in its applications. Imagine: SHAPESHIFTING ACTORS.

game/engines/default/engine/Zone.lua

@@ -467,6 +467,76 @@ 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, no_name_change)
+	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 = e.name
+	if not no_name_change then
+		if ego.prefix then newname = ego.name .. e.name
+		else newname = e.name .. ego.name end
+	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, no_name_change}
+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:getEgoByName(e, ego_name)
+	for i, v in ipairs(e.ego_list or {}) do
+		if v[1].name == ego_name then return v[1] end
+	end
+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[1]) end
+	end
+end
+
--- Finishes generating an entity
function _M:finishEntity(level, type, e, ego_filter)
e = e:clone()
@@ -480,25 +550,7 @@ 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 +622,7 @@ 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()