From 20cd7ab38e8177edbf742484f1e8db0d6ddd268a Mon Sep 17 00:00:00 2001
From: Cadence Ember <cadence@disroot.org>
Date: Fri, 25 Aug 2023 17:23:51 +1200
Subject: [PATCH] sync child room avatars when guild is updated

---
 d2m/actions/create-room.js  | 27 ++++++++++++++++-----------
 d2m/actions/create-space.js | 24 ++++++++++++++++++++++--
 2 files changed, 38 insertions(+), 13 deletions(-)

diff --git a/d2m/actions/create-room.js b/d2m/actions/create-room.js
index 6fbc42ee..20951301 100644
--- a/d2m/actions/create-room.js
+++ b/d2m/actions/create-room.js
@@ -17,6 +17,7 @@ const ks = sync.require("../../matrix/kstate")
 const inflightRoomCreate = new Map()
 
 /**
+ * Async because it gets all room state from the homeserver.
  * @param {string} roomID
  */
 async function roomToKState(roomID) {
@@ -60,6 +61,7 @@ function convertNameAndTopic(channel, guild, customName) {
 }
 
 /**
+ * Async because it may upload the guild icon to mxc.
  * @param {DiscordTypes.APIGuildTextChannel | DiscordTypes.APIThreadChannel} channel
  * @param {DiscordTypes.APIGuild} guild
  */
@@ -200,10 +202,10 @@ function channelToGuild(channel) {
 	3. Get kstate for channel
 	4. Create room, return new ID
 
-	New combined flow with ensure / sync:
+	Ensure + sync flow:
 	1. Get IDs
 	2. Does room exist?
-	2.5: If room does exist AND don't need to sync: return here
+	2.5: If room does exist AND wasn't asked to sync: return here
 	3. Get kstate for channel
 	4. Create room with kstate if room doesn't exist
 	5. Get and update room state with kstate if room does exist
@@ -246,7 +248,7 @@ async function _syncRoom(channelID, shouldActuallySync) {
 
 	console.log(`[room sync] to matrix: ${channel.name}`)
 
-	const {spaceID, channelKState} = await channelToKState(channel, guild)
+	const {spaceID, channelKState} = await channelToKState(channel, guild) // calling this in both branches because we don't want to calculate this if not syncing
 
 	// sync channel state to room
 	const roomKState = await roomToKState(roomID)
@@ -261,6 +263,16 @@ async function _syncRoom(channelID, shouldActuallySync) {
 	return roomID
 }
 
+/** Ensures the room exists. If it doesn't, creates the room with an accurate initial state. */
+function ensureRoom(channelID) {
+	return _syncRoom(channelID, false)
+}
+
+/** Actually syncs. Gets all room state from the homeserver in order to diff, and uploads the icon to mxc if it has changed. */
+function syncRoom(channelID) {
+	return _syncRoom(channelID, true)
+}
+
 async function _unbridgeRoom(channelID) {
 	/** @ts-ignore @type {DiscordTypes.APIGuildChannel} */
 	const channel = discord.channels.get(channelID)
@@ -289,6 +301,7 @@ async function _unbridgeRoom(channelID) {
 
 
 /**
+ * Async because it gets all space state from the homeserver, then if necessary sends one state event back.
  * @param {DiscordTypes.APIGuildTextChannel} channel
  * @param {string} spaceID
  * @param {string} roomID
@@ -311,14 +324,6 @@ async function _syncSpaceMember(channel, spaceID, roomID) {
 	return applyKStateDiffToRoom(spaceID, spaceDiff)
 }
 
-function ensureRoom(channelID) {
-	return _syncRoom(channelID, false)
-}
-
-function syncRoom(channelID) {
-	return _syncRoom(channelID, true)
-}
-
 async function createAllForGuild(guildID) {
 	const channelIDs = discord.guildChannelMap.get(guildID)
 	assert.ok(channelIDs)
diff --git a/d2m/actions/create-space.js b/d2m/actions/create-space.js
index 46fa71f5..838bef90 100644
--- a/d2m/actions/create-space.js
+++ b/d2m/actions/create-space.js
@@ -1,6 +1,6 @@
 // @ts-check
 
-const assert = require("assert")
+const assert = require("assert").strict
 const DiscordTypes = require("discord-api-types/v10")
 
 const passthrough = require("../../passthrough")
@@ -84,11 +84,31 @@ async function syncSpace(guildID) {
 
 	console.log(`[space sync] to matrix: ${guild.name}`)
 
-	// sync channel state to room
+	// sync guild state to space
 	const spaceKState = await createRoom.roomToKState(spaceID)
 	const spaceDiff = ks.diffKState(spaceKState, guildKState)
 	await createRoom.applyKStateDiffToRoom(spaceID, spaceDiff)
 
+	// guild icon was changed, so room avatars need to be updated as well as the space ones
+	// doing it this way rather than calling syncRoom for great efficiency gains
+	const newAvatarState = spaceDiff["m.room.avatar/"]
+	if (guild.icon && newAvatarState?.url) {
+		// don't try to update rooms with custom avatars though
+		const roomsWithCustomAvatars = db.prepare("SELECT room_id FROM channel_room WHERE custom_avatar IS NOT NULL").pluck().all()
+
+		const childRooms = ks.kstateToState(spaceKState).filter(({type, state_key, content}) => {
+			return type === "m.space.child" && "via" in content && roomsWithCustomAvatars.includes(state_key)
+		}).map(({state_key}) => state_key)
+
+		for (const roomID of childRooms) {
+			const avatarEventContent = await api.getStateEvent(roomID, "m.room.avatar", "")
+			if (avatarEventContent.url !== newAvatarState.url) {
+				await api.sendState(roomID, "m.room.avatar", "", newAvatarState)
+			}
+		}
+	}
+
+
 	return spaceID
 }