Damage System: detect damage.Type of Playey|Entity hand. Closes #1634

mods/lord/Core/damage/src/damage/Type.lua

@@ -1,7 +1,8 @@
-local assert, table_contains, pairs, typeof
-    = assert, table.contains, pairs, type
+local assert, table_contains, typeof
+    = assert, table.contains, type
 
-local TypeEvent = require('damage.Type.Event')
+local TypeEvent    = require('damage.Type.Event')
+local TypeResolver = require('damage.Type.Resolver')
 
 
 --- @static
@@ -19,6 +20,8 @@ local Type = {
 	}
 }
 
+TypeResolver.init(Type.registered)
+
 --- @param name string
 --- @return damage.Type
 function Type.register(name)
@@ -47,61 +50,28 @@ end
 --- @param damage_groups table<string,number>
 --- @return string|nil
 function Type.get_from_groups(damage_groups)
-	for type, damage in pairs(damage_groups) do
-		if table_contains(Type.registered, type) then
-			return type
-		end
-	end
-
-	return nil
+	return TypeResolver.by_damage_groups(damage_groups)
 end
 
 --- @param definition ItemDefinition
 --- @return string|nil
 function Type.get_by_definition(definition)
-	local damage_groups = definition.damage_groups or (
-		definition.tool_capabilities
-			and (definition.tool_capabilities.damage_groups or {})
-			or {}
-	)
-
-	return Type.get_from_groups(damage_groups)
+	return TypeResolver.by_definition(definition)
 end
 
 --- @param reason PlayerHPChangeReason
 --- @return string
 function Type.detect(reason)
-	local type = Type.get_default()
-	assert(typeof(type) == 'string')
-
-	if reason.type == 'node_damage' and reason.node then
-
-		return Type.get_by_definition(minetest.registered_nodes[reason.node]) or type
+	local default_type = Type.get_default()
+	assert(typeof(default_type) == 'string')
 
-	elseif reason.type == 'punch' and reason.object then
-
-		--- @type Player|Entity
-		local player_or_mob   = reason.object
-		local item_definition = player_or_mob:get_wielded_item():get_definition()
-
-		return Type.get_by_definition(item_definition) or type
-
-	end
-
-	return type
+	return TypeResolver.by_reason(reason) or default_type
 end
 
 --- @return string[]
 function Type.get_registered()
 	return Type.registered
 end
 
-setmetatable(Type, {
-	--- @return fun(registered:string[]): (number, string)
-	__pairs = function()
-		return pairs(Type.registered)
-	end
-})
-
 
 return Type

mods/lord/Core/damage/src/damage/Type/Resolver.lua

@@ -0,0 +1,75 @@
+local table_contains, pairs
+	= table.contains, pairs
+
+
+--- @static
+--- @class damage.Type.Resolver
+local Resolver = {
+	--- @private
+	--- @static
+	--- @type string[]
+	damage_types = nil
+}
+
+--- @param registered_damage_types string[]
+--- @return damage.Type.Resolver
+function Resolver.init(registered_damage_types)
+	Resolver.damage_types = registered_damage_types
+
+	return Resolver
+end
+
+--- @param damage_groups table<string,number>
+--- @return string|nil
+function Resolver.by_damage_groups(damage_groups)
+	for type, damage in pairs(damage_groups) do
+		if table_contains(Resolver.damage_types, type) then
+			return type
+		end
+	end
+
+	return nil
+end
+
+--- @param definition ItemDefinition
+--- @return string|nil
+function Resolver.by_definition(definition)
+	local damage_groups = definition.damage_groups or (
+		definition.tool_capabilities
+			and (definition.tool_capabilities.damage_groups or {})
+			or {}
+	)
+
+	return Resolver.by_damage_groups(damage_groups)
+end
+
+--- @param reason PlayerHPChangeReason
+--- @return string|nil
+function Resolver.by_reason(reason)
+
+	if reason.type == 'node_damage' and reason.node then
+
+		return Resolver.by_definition(minetest.registered_nodes[reason.node])
+
+	elseif reason.type == 'punch' and reason.object then
+
+		--- @type Player|Entity
+		local player_or_mob = reason.object
+		local item = player_or_mob:get_wielded_item()
+
+		if player_or_mob:is_player() then                                    -- `damage.Type` of:
+			return Resolver.by_definition(item:get_definition())         -- Player wielded item
+				or Resolver.by_definition(minetest.registered_nodes[""]) -- Player hand
+		else
+			return item:get_name() ~= ""                                 -- `damage.Type` of:
+				and Resolver.by_definition(item:get_definition())    -- Entity wielded item
+				or  player_or_mob:get_luaentity().damage_type            -- Entity hand
+		end
+
+	end
+
+	return nil
+end
+
+
+return Resolver