add: ability to transfer community ownership

crates/core/src/database/communities.rs

@@ -397,6 +397,68 @@ impl DataManager {
         Ok(())
     }
 
+    pub async fn update_community_owner(
+        &self,
+        id: usize,
+        user: User,
+        new_owner: usize,
+    ) -> Result<()> {
+        let y = self.get_community_by_id(id).await?;
+
+        if user.id != y.owner {
+            if !user.permissions.check(FinePermission::MANAGE_COMMUNITIES) {
+                return Err(Error::NotAllowed);
+            } else {
+                self.create_audit_log_entry(crate::model::moderation::AuditLogEntry::new(
+                    user.id,
+                    format!("invoked `update_community_owner` with x value `{id}`"),
+                ))
+                .await?
+            }
+        }
+
+        let new_owner_membership = self
+            .get_membership_by_owner_community(new_owner, y.id)
+            .await?;
+        let current_owner_membership = self
+            .get_membership_by_owner_community(y.owner, y.id)
+            .await?;
+
+        // ...
+        let conn = match self.connect().await {
+            Ok(c) => c,
+            Err(e) => return Err(Error::DatabaseConnection(e.to_string())),
+        };
+
+        let res = execute!(
+            &conn,
+            "UPDATE communities SET owner = $1 WHERE id = $2",
+            params![&(new_owner as i64), &(id as i64)]
+        );
+
+        if let Err(e) = res {
+            return Err(Error::DatabaseError(e.to_string()));
+        }
+
+        self.cache_clear_community(&y).await;
+
+        // update memberships
+        self.update_membership_role(
+            new_owner_membership.id,
+            CommunityPermission::DEFAULT | CommunityPermission::ADMINISTRATOR,
+        )
+        .await?;
+
+        self.update_membership_role(
+            current_owner_membership.id,
+            CommunityPermission::DEFAULT | CommunityPermission::MEMBER,
+        )
+        .await?;
+
+        // return
+        Ok(())
+    }
+
     auto_method!(update_community_context(CommunityContext)@get_community_by_id_no_void:MANAGE_COMMUNITIES -> "UPDATE communities SET context = $1 WHERE id = $2" --serde --cache-key-tmpl=cache_clear_community);
     auto_method!(update_community_read_access(CommunityReadAccess)@get_community_by_id_no_void:MANAGE_COMMUNITIES -> "UPDATE communities SET read_access = $1 WHERE id = $2" --serde --cache-key-tmpl=cache_clear_community);
     auto_method!(update_community_write_access(CommunityWriteAccess)@get_community_by_id_no_void:MANAGE_COMMUNITIES -> "UPDATE communities SET write_access = $1 WHERE id = $2" --serde --cache-key-tmpl=cache_clear_community);