fix invites

packages/domain/src/relationships-db.ts

@@ -0,0 +1,56 @@
+/**
+ * Read-only access to the friendship graph on the shared `recflare` D1 database.
+ *
+ * The `relationship` table's schema and every mutation are owned by the `api` worker
+ * (apps/api/src/relationships-db.ts, migrations/0001_relationship.sql). This module is
+ * the shared *reader* other workers need: the `match` worker looks up a player's friends
+ * to push a presence update to them when the player changes rooms. It only SELECTs the
+ * three columns that identify a friendship (requester/target/type), so it stays
+ * decoupled from the favorited/ignored/muted flag columns api layers on top.
+ */
+
+/**
+ * `relationship_type` for a mutual friendship — mirror of api's `RelationshipType.Friend`.
+ * Pending requests (1 sent / 2 received) and bare ignore/mute rows (0) are not friends.
+ */
+const FRIEND_RELATIONSHIP_TYPE = 3
+
+/**
+ * The account ids of a player's mutual friends. Exactly one relationship row exists per
+ * unordered pair, with the player on either side, so this reads both directions and
+ * returns whichever id isn't the player. Non-friend rows are excluded; the order is
+ * unspecified.
+ */
+export async function getFriendIds(db: D1Database, playerId: number): Promise<number[]> {
+	const { results } = await db
+		.prepare(
+			`SELECT requester_id, target_id FROM relationship
+			 WHERE relationship_type = ?2 AND (requester_id = ?1 OR target_id = ?1)`
+		)
+		.bind(playerId, FRIEND_RELATIONSHIP_TYPE)
+		.all<{ requester_id: number; target_id: number }>()
+	return results.map((r) => (r.requester_id === playerId ? r.target_id : r.requester_id))
+}
+
+/**
+ * Whether two players are mutual friends. The single relationship row for the pair sits
+ * in either direction, so both are checked. A targeted single-row read — cheaper than
+ * {@link getFriendIds} when all you need is "are these two friends?" (e.g. gating a
+ * follow-a-friend matchmake).
+ */
+export async function areFriends(
+	db: D1Database,
+	playerId: number,
+	otherId: number
+): Promise<boolean> {
+	const row = await db
+		.prepare(
+			`SELECT 1 AS ok FROM relationship
+			 WHERE relationship_type = ?3
+			   AND ((requester_id = ?1 AND target_id = ?2) OR (requester_id = ?2 AND target_id = ?1))
+			 LIMIT 1`
+		)
+		.bind(playerId, otherId, FRIEND_RELATIONSHIP_TYPE)
+		.first<{ ok: number }>()
+	return row !== null
+}