From e107d6d448be03a2bdb703106c38f20e1dbefc78 Mon Sep 17 00:00:00 2001
From: tsa96 <tom@trumpetdust.org>
Date: Mon, 15 Apr 2024 12:01:03 +0100
Subject: [PATCH] feat: RegisterHUDPanelForGamemode

:D
---
 scripts/util/register-for-gamemodes.ts | 167 +++++++++++++++++++++++++
 1 file changed, 167 insertions(+)
 create mode 100644 scripts/util/register-for-gamemodes.ts

diff --git a/scripts/util/register-for-gamemodes.ts b/scripts/util/register-for-gamemodes.ts
new file mode 100644
index 00000000..cd817826
--- /dev/null
+++ b/scripts/util/register-for-gamemodes.ts
@@ -0,0 +1,167 @@
+/**
+ * Pass an event that should be only registered when playing certain gamemodes.
+ *
+ * This function will register/unregister the provided events handler when gamemodes change.
+ *
+ * It returns a function that will clean up both event handlers. It's unlikely we'll ever need to use it,
+ * so usually you can just discard it.
+ *
+ * @example
+ * ```ts
+ * // In the static initializer block for some panel's class, call the onUpdate function on this class
+ * // whenever the 'HudProcessInput' event is fired, ONLY if the current gamemode is Gamemode.DEFRAG.
+ * 	static {
+ * 		RegisterEventForGamemodes(
+ * 			[GameMode.DEFRAG],
+ * 			'HudProcessInput',
+ * 			$.GetContextPanel(),
+ * 			this.onUpdate.bind(this)
+ * 		);
+ * 	}
+ * ```
+ * @param gamemodes - Gamemodes to register the callback for. Handler is unregistered for any other modes.
+ * @param event - Event name
+ * @param context - Panel context
+ * @param callbackFn - Event callback
+ * @returns Cleanup function that unregisters both event handlers
+ */
+function RegisterEventForGamemodes(
+	gamemodes: number[],
+	event: string,
+	context: string | Panel,
+	callbackFn: (...args: unknown[]) => void
+): () => void {
+	let innerHandle: number | undefined;
+	const outerHandle = $.RegisterForUnhandledEvent('LevelInitPostEntity', () => {
+		// @ts-expect-error - TODO: Typings for this API
+		if (!innerHandle && gamemodes.includes(GameModeAPI.GetCurrentGameMode())) {
+			innerHandle = $.RegisterEventHandler(event, context, callbackFn);
+		} else if (innerHandle) {
+			$.UnregisterEventHandler(event, context, innerHandle);
+			innerHandle = undefined;
+		}
+	});
+
+	return () => {
+		if (innerHandle) {
+			$.UnregisterEventHandler(event, context, innerHandle);
+		}
+
+		$.UnregisterForUnhandledEvent('LevelInitPostEntity', outerHandle);
+	};
+}
+
+interface RegisterHUDPanelForGamemodeOptions {
+	context: object;
+	contextPanel: Panel;
+	gamemodes: number[];
+	onLoad?: Func;
+	handledEvents?: Array<{ event: string; callback: Func; contextPanel: Panel }>;
+	unhandledEvents?: Array<{ event: string; callback: Func }>;
+}
+
+/**
+ * Mark a panel as being only active in the given gamemodes.
+ *
+ * The panel will be set to `visible=true` in the given modes, and `false` in all others.
+ *
+ * Any events provided will be registered at `LevelInitPostEntity` when the given a map is launched in the provided
+ * modes, and unregistered in any other modes.
+ *
+ * An optional `onLoad` function will be called whenever a launched in the provided modes.
+ *
+ * You must provide the current JS context with `context`, and don't need to use `.bind(this)` on any functions you pass.
+ *
+ * @example
+ * // Simplest usage, only visible in SURF.
+ * class MyEpicSurfPanel {
+ *   static {
+ *     RegisterHUDPanelForGamemode({
+ *       gamemodes: [Gamemode.SURF],
+ *       context: this,
+ *       contextPanel: $.GetContextPanel()
+ *     })
+ *   }
+ * }
+ *
+ * // More advanced example.
+ * class MyFuckedUpBhopPanel {
+ *   static {
+ *     RegisterHUDPanelForGamemode({
+ *        gamemodes: [Gamemode.BHOP],
+ *        context: this,
+ *        contextPanel: $.GetContextPanel(),
+ *        onLoad: this.setup,
+ *        handledEvents: [{
+ *          event: 'HudProcessInput',
+ *          callback: this.onUpdate,
+ *          contextPanel: $.GetContextPanel()
+ *        }]
+ *     })
+ *   }
+ *
+ *   static setup() {
+ *     // ...
+ *   }
+ *
+ *   static onUpdate() {
+ *     // ...
+ *   }
+ * }
+ *
+ * @returns Cleanup function that unregisters all event handlers
+ */
+function RegisterHUDPanelForGamemode({
+	context,
+	contextPanel,
+	onLoad,
+	gamemodes,
+	handledEvents,
+	unhandledEvents
+}: RegisterHUDPanelForGamemodeOptions): () => void {
+	if (!(gamemodes?.length > 0)) {
+		throw new Error('RegisterHUDPanelForGamemode: no gamemode provided');
+	}
+
+	let handles: Array<{ event: string; handle: number; contextPanel?: Panel }>;
+
+	const unregister = () =>
+		(handles ?? []).forEach(({ event, handle, contextPanel }) =>
+			contextPanel === undefined
+				? $.UnregisterForUnhandledEvent(event, handle)
+				: $.UnregisterEventHandler(event, contextPanel, handle)
+		);
+
+	const handle = $.RegisterForUnhandledEvent('LevelInitPostEntity', () => {
+		unregister();
+		handles = [];
+
+		// @ts-expect-error - TODO: Typings for this API
+		if (gamemodes.includes(GameModeAPI.GetCurrentGameMode())) {
+			contextPanel.visible = true;
+			onLoad?.call(context);
+
+			for (const { event, callback } of unhandledEvents ?? []) {
+				handles.push({
+					event,
+					handle: $.RegisterForUnhandledEvent(event, callback.bind(context))
+				});
+			}
+
+			for (const { event, contextPanel, callback } of handledEvents ?? []) {
+				handles.push({
+					event,
+					contextPanel,
+					handle: $.RegisterEventHandler(event, contextPanel, callback.bind(context))
+				});
+			}
+		} else {
+			contextPanel.visible = false;
+		}
+	});
+
+	return () => {
+		unregister();
+		$.UnregisterForUnhandledEvent('LevelInitPostEntity', handle);
+	};
+}