roblox_emulator: implement CoerceEnum

lib/roblox_emulator/src/runner/enum.rs

@@ -46,6 +46,48 @@ pub struct EnumItems<'a>{
 	ed:&'a rbx_reflection::EnumDescriptor<'a>,
 }
 
+impl<'a> EnumItems<'a>{
+	pub fn from_value(&self,value:u32)->Option<EnumItem<'a>>{
+		self.ed.items.iter().find(|&(_,&v)|v==value).map(EnumItem::known_name)
+	}
+	pub fn from_name(&self,name:&str)->Option<EnumItem<'a>>{
+		self.ed.items.get_key_value(name).map(EnumItem::known_name)
+	}
+	pub fn from_enum(&self,enum_item:EnumItem)->Option<EnumItem<'a>>{
+		match enum_item.name{
+			Some(s)=>{
+				let got=self.from_name(s)?;
+				(got.value==enum_item.value).then_some(got)
+			},
+			None=>self.from_value(enum_item.value)
+		}
+	}
+	pub fn coerce(&self,e:CoerceEnum)->mlua::Result<EnumItem<'a>>{
+		match e{
+			CoerceEnum::Integer(int)=>self.from_value(int as u32),
+			CoerceEnum::String(s)=>self.from_name(&*s.to_str()?),
+			CoerceEnum::Enum(enum_item)=>self.from_enum(enum_item),
+		}.ok_or_else(||mlua::Error::runtime(format!("Bad {} EnumItem",self.ed.name)))
+	}
+}
+
+pub enum CoerceEnum<'a>{
+	Integer(i32),
+	String(mlua::String),
+	Enum(EnumItem<'a>),
+}
+
+impl mlua::FromLua for CoerceEnum<'_>{
+	fn from_lua(value:mlua::Value,_lua:&mlua::Lua)->Result<Self,mlua::Error>{
+		match value{
+			mlua::Value::Integer(int)=>Ok(CoerceEnum::Integer(int)),
+			mlua::Value::String(s)=>Ok(CoerceEnum::String(s)),
+			mlua::Value::UserData(ud)=>Ok(CoerceEnum::Enum(*ud.borrow()?)),
+			other=>Err(mlua::Error::runtime(format!("Expected {} got {:?}",stringify!(Enum),other))),
+		}
+	}
+}
+
 pub fn set_globals(_lua:&mlua::Lua,globals:&mlua::Table)->Result<(),mlua::Error>{
 	globals.set("Enum",Enums)
 }
@@ -54,6 +96,8 @@ impl mlua::UserData for EnumItems<'static>{
 	fn add_fields<F:mlua::UserDataFields<Self>>(_fields:&mut F){
 	}
 	fn add_methods<M:mlua::UserDataMethods<Self>>(methods:&mut M){
+		methods.add_method("FromName",|_,this:&EnumItems,name:mlua::String|Ok(this.from_name(&*name.to_str()?)));
+		methods.add_method("FromValue",|_,this:&EnumItems,value:u32|Ok(this.from_value(value)));
 		methods.add_method("GetEnumItems",|_,this:&EnumItems,()|->mlua::Result<Vec<EnumItem>>{
 			Ok(this.ed.items.iter().map(EnumItem::known_name).collect())
 		});