72 lines
2.8 KiB
TypeScript
72 lines
2.8 KiB
TypeScript
/*
|
|
Copyright 2019-2024 New Vector Ltd.
|
|
|
|
SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
|
|
Please see LICENSE files in the repository root for full details.
|
|
*/
|
|
|
|
import { SettingLevel } from "./SettingLevel";
|
|
|
|
export type CallbackFn = (changedInRoomId: string | null, atLevel: SettingLevel, newValAtLevel: any) => void;
|
|
|
|
const IRRELEVANT_ROOM: string | null = null;
|
|
|
|
/**
|
|
* Generalized management class for dealing with watchers on a per-handler (per-level)
|
|
* basis without duplicating code. Handlers are expected to push updates through this
|
|
* class, which are then proxied outwards to any applicable watchers.
|
|
*/
|
|
export class WatchManager {
|
|
private watchers = new Map<string, Map<string | null, CallbackFn[]>>(); // settingName -> roomId -> CallbackFn[]
|
|
|
|
// Proxy for handlers to delegate changes to this manager
|
|
public watchSetting(settingName: string, roomId: string | null, cb: CallbackFn): void {
|
|
if (!this.watchers.has(settingName)) this.watchers.set(settingName, new Map());
|
|
if (!this.watchers.get(settingName)!.has(roomId)) this.watchers.get(settingName)!.set(roomId, []);
|
|
this.watchers.get(settingName)!.get(roomId)!.push(cb);
|
|
}
|
|
|
|
// Proxy for handlers to delegate changes to this manager
|
|
public unwatchSetting(cb: CallbackFn): void {
|
|
this.watchers.forEach((map) => {
|
|
map.forEach((callbacks) => {
|
|
let idx: number;
|
|
while ((idx = callbacks.indexOf(cb)) !== -1) {
|
|
callbacks.splice(idx, 1);
|
|
}
|
|
});
|
|
});
|
|
}
|
|
|
|
public notifyUpdate(
|
|
settingName: string,
|
|
inRoomId: string | null,
|
|
atLevel: SettingLevel,
|
|
newValueAtLevel: any,
|
|
): void {
|
|
// Dev note: We could avoid raising changes for ultimately inconsequential changes, but
|
|
// we also don't have a reliable way to get the old value of a setting. Instead, we'll just
|
|
// let it fall through regardless and let the receiver dedupe if they want to.
|
|
|
|
if (!this.watchers.has(settingName)) return;
|
|
|
|
const roomWatchers = this.watchers.get(settingName)!;
|
|
const callbacks: CallbackFn[] = [];
|
|
|
|
if (inRoomId !== null && roomWatchers.has(inRoomId)) {
|
|
callbacks.push(...roomWatchers.get(inRoomId)!);
|
|
}
|
|
|
|
if (!inRoomId) {
|
|
// Fire updates to all the individual room watchers too, as they probably care about the change higher up.
|
|
callbacks.push(...Array.from(roomWatchers.values()).flat(1));
|
|
} else if (roomWatchers.has(IRRELEVANT_ROOM)) {
|
|
callbacks.push(...roomWatchers.get(IRRELEVANT_ROOM)!);
|
|
}
|
|
|
|
for (const callback of callbacks) {
|
|
callback(inRoomId, atLevel, newValueAtLevel);
|
|
}
|
|
}
|
|
}
|