refactor(base): Store RoomPowerLevels in RoomMember

Avoids to carry around the event content only to convert it when we
want to use it. Avoids also to carry around the room creator when we
might not need it.

Signed-off-by: Kévin Commaille <zecakeh@tedomum.fr>

Author: zecakeh

crates/matrix-sdk-base/src/room/members.rs

@@ -25,7 +25,7 @@ use ruma::{
         presence::PresenceEvent,
         room::{
             member::{MembershipState, RoomMemberEventContent},
-            power_levels::{PowerLevelAction, RoomPowerLevels, RoomPowerLevelsEventContent},
+            power_levels::{PowerLevelAction, RoomPowerLevels},
         },
         MessageLikeEventType, StateEventType,
     },
@@ -35,7 +35,7 @@ use tracing::debug;
 
 use super::Room;
 use crate::{
-    deserialized_responses::{DisplayName, MemberEvent, SyncOrStrippedState},
+    deserialized_responses::{DisplayName, MemberEvent},
     store::{ambiguity_map::is_display_name_ambiguous, Result as StoreResult, StateStoreExt},
     MinimalRoomMemberEvent,
 };
@@ -166,13 +166,7 @@ impl Room {
         display_names: &'a [DisplayName],
     ) -> StoreResult<MemberRoomInfo<'a>> {
         let max_power_level = self.max_power_level();
-        let room_creator = self.inner.read().creator().map(ToOwned::to_owned);
-
-        let power_levels = self
-            .store
-            .get_state_event_static(self.room_id())
-            .await?
-            .and_then(|e| e.deserialize().ok());
+        let power_levels = self.power_levels_or_default().await;
 
         let users_display_names =
             self.store.get_users_with_display_names(self.room_id(), display_names).await?;
@@ -188,7 +182,6 @@ impl Room {
         Ok(MemberRoomInfo {
             power_levels: power_levels.into(),
             max_power_level,
-            room_creator,
             users_display_names,
             ignored_users,
         })
@@ -205,9 +198,8 @@ pub struct RoomMember {
     pub(crate) profile: Arc<Option<MinimalRoomMemberEvent>>,
     #[allow(dead_code)]
     pub(crate) presence: Arc<Option<PresenceEvent>>,
-    pub(crate) power_levels: Arc<Option<SyncOrStrippedState<RoomPowerLevelsEventContent>>>,
+    pub(crate) power_levels: Arc<RoomPowerLevels>,
     pub(crate) max_power_level: i64,
-    pub(crate) is_room_creator: bool,
     pub(crate) display_name_ambiguous: bool,
     pub(crate) is_ignored: bool,
 }
@@ -219,15 +211,9 @@ impl RoomMember {
         presence: Option<PresenceEvent>,
         room_info: &MemberRoomInfo<'_>,
     ) -> Self {
-        let MemberRoomInfo {
-            power_levels,
-            max_power_level,
-            room_creator,
-            users_display_names,
-            ignored_users,
-        } = room_info;
+        let MemberRoomInfo { power_levels, max_power_level, users_display_names, ignored_users } =
+            room_info;
 
-        let is_room_creator = room_creator.as_deref() == Some(event.user_id());
         let display_name = event.display_name();
         let display_name_ambiguous = users_display_names
             .get(&display_name)
@@ -240,7 +226,6 @@ impl RoomMember {
             presence: presence.into(),
             power_levels: power_levels.clone(),
             max_power_level: *max_power_level,
-            is_room_creator,
             display_name_ambiguous,
             is_ignored,
         }
@@ -301,10 +286,7 @@ impl RoomMember {
 
     /// Get the power level of this member.
     pub fn power_level(&self) -> i64 {
-        (*self.power_levels)
-            .as_ref()
-            .map(|e| e.power_levels().for_user(self.user_id()).into())
-            .unwrap_or_else(|| if self.is_room_creator { 100 } else { 0 })
+        self.power_levels.for_user(self.user_id()).into()
     }
 
     /// Whether this user can ban other users based on the power levels.
@@ -377,11 +359,8 @@ impl RoomMember {
         self.can_do_impl(|pls| pls.user_can_do(self.user_id(), action))
     }
 
-    fn can_do_impl(&self, f: impl FnOnce(RoomPowerLevels) -> bool) -> bool {
-        match &*self.power_levels {
-            Some(event) => f(event.power_levels()),
-            None => self.is_room_creator,
-        }
+    fn can_do_impl(&self, f: impl FnOnce(&RoomPowerLevels) -> bool) -> bool {
+        f(&self.power_levels)
     }
 
     /// Is the name that the member uses ambiguous in the room.
@@ -405,9 +384,8 @@ impl RoomMember {
 
 // Information about the room a member is in.
 pub(crate) struct MemberRoomInfo<'a> {
-    pub(crate) power_levels: Arc<Option<SyncOrStrippedState<RoomPowerLevelsEventContent>>>,
+    pub(crate) power_levels: Arc<RoomPowerLevels>,
     pub(crate) max_power_level: i64,
-    pub(crate) room_creator: Option<OwnedUserId>,
     pub(crate) users_display_names: HashMap<&'a DisplayName, BTreeSet<OwnedUserId>>,
     pub(crate) ignored_users: Option<BTreeSet<OwnedUserId>>,
 }

crates/matrix-sdk-base/src/room/mod.rs

@@ -47,9 +47,8 @@ pub use room_info::{
     apply_redaction, BaseRoomInfo, InviteAcceptanceDetails, RoomInfo, RoomInfoNotableUpdate,
     RoomInfoNotableUpdateReasons,
 };
-#[cfg(feature = "e2e-encryption")]
-use ruma::{events::AnySyncTimelineEvent, serde::Raw};
 use ruma::{
+    assign,
     events::{
         direct::OwnedDirectUserIdentifier,
         receipt::{Receipt, ReceiptThread, ReceiptType},
@@ -61,9 +60,12 @@ use ruma::{
             power_levels::{RoomPowerLevels, RoomPowerLevelsEventContent},
         },
     },
+    int,
     room::RoomType,
     EventId, OwnedEventId, OwnedMxcUri, OwnedRoomAliasId, OwnedRoomId, OwnedUserId, RoomId, UserId,
 };
+#[cfg(feature = "e2e-encryption")]
+use ruma::{events::AnySyncTimelineEvent, serde::Raw};
 use serde::{Deserialize, Serialize};
 pub use state::{RoomState, RoomStateFilter};
 pub(crate) use tags::RoomNotableTags;
@@ -371,6 +373,23 @@ impl Room {
             .power_levels())
     }
 
+    /// Get the current power levels of this room, or a sensible default if they
+    /// are not known.
+    pub async fn power_levels_or_default(&self) -> RoomPowerLevels {
+        if let Ok(power_levels) = self.power_levels().await {
+            return power_levels;
+        }
+
+        // As a fallback, create the default power levels of a room, with the creator at
+        // level 100.
+        let creator = self.creator();
+        assign!(
+            RoomPowerLevelsEventContent::new(),
+            { users: creator.into_iter().map(|user_id| (user_id, int!(100))).collect() }
+        )
+        .into()
+    }
+
     /// Get the `m.room.name` of this room.
     ///
     /// The returned string may be empty if the event has been redacted, or it's