Add is_direct() query for account_data.

Signed-off-by: Jason Volk <jason@zemos.net>

src/service/account_data/direct.rs

@@ -0,0 +1,19 @@
+use ruma::{
+	RoomId, UserId,
+	events::{GlobalAccountDataEventType, direct::DirectEventContent},
+};
+use tuwunel_core::{at, implement, is_equal_to};
+
+#[implement(super::Service)]
+pub async fn is_direct(&self, user_id: &UserId, room_id: &RoomId) -> bool {
+	self.services
+		.account_data
+		.get_global(user_id, GlobalAccountDataEventType::Direct)
+		.await
+		.map(|content: DirectEventContent| content)
+		.into_iter()
+		.flat_map(DirectEventContent::into_iter)
+		.map(at!(1))
+		.flat_map(Vec::into_iter)
+		.any(is_equal_to!(room_id))
+}

src/service/account_data/mod.rs

@@ -1,3 +1,4 @@
+mod direct;
 mod room_tags;
 
 use std::sync::Arc;