1 files changed, 68 insertions, 0 deletions
diff --git a/static/event-hub.interfaces.ts b/static/event-hub.interfaces.ts
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+++ b/static/event-hub.interfaces.ts
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+// Copyright (c) 2022, Compiler Explorer Authors
+// All rights reserved.
+//
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are met:
+//
+//     * Redistributions of source code must retain the above copyright notice,
+//       this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above copyright
+//       notice, this list of conditions and the following disclaimer in the
+//       documentation and/or other materials provided with the distribution.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
+// AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+// IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+// ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE
+// LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
+// CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
+// SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
+// INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
+// CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
+// ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+// POSSIBILITY OF SUCH DAMAGE.
+
+/* eslint-disable @typescript-eslint/adjacent-overload-signatures -- nicer format */
+
+import { SiteSettings } from './settings';
+
+/**
+ * Exhaustive enumeration of all possible events the Hub's event emitter
+ * can emit.
+ */
+export type EventKeys =
+    | 'settingsChange'
+    | 'requestSettings'
+    | 'modifySettings'
+
+    | 'astViewOpened'
+    ;
+
+/**
+ * A mapping from event name to a tuple of the arguments that the event expects
+ * to be passed to the event emitter's `emit` method.
+ */
+export interface EventHubArguments extends Record<EventKeys, [...args: any]> {
+    settingsChange: [SiteSettings];
+    requestSettings: [];
+    modifySettings: [Partial<SiteSettings>];
+
+    astViewOpened: [number];
+}
+
+/**
+ * A mapping from event name to the type the callback function that should be
+ * passed to the event emitter's `on` method.
+ */
+export interface EventHubListeners extends Record<EventKeys, (...args: any) => any> {
+    settingsChange: (settings: SiteSettings) => void;
+    requestSettings: () => void;
+    modifySettings: (settings: SiteSettings) => void;
+
+    astViewOpened: (id: number) => void;
+}
+
+export interface EventHubEvents {
+    on: <K extends EventKeys>(event: K, listener: EventHubListeners[K]) => void;
+    emit: <K extends EventKeys>(event: K, ...args: EventHubArguments[K]) => void;
+}