Presences/websites/W/Wikivoyage/presence.ts

const presence = new Presence({
	clientId: "733216959382159400",
});

let currentURL = new URL(document.location.href),
	currentPath = currentURL.pathname.replace(/^\/|\/$/g, "").split("/");
const browsingTimestamp = Math.floor(Date.now() / 1000);
let presenceData: PresenceData = {
	details: "Viewing an unsupported page",
	largeImageKey:
		"https://cdn.rcd.gg/PreMiD/websites/W/Wikivoyage/assets/logo.png",
	startTimestamp: browsingTimestamp,
};
const updateCallback = {
		_function: null as () => void,
		get function(): () => void {
			return this._function;
		},
		set function(parameter) {
			this._function = parameter;
		},
		get present(): boolean {
			return this._function !== null;
		},
	},
	/**
	 * Initialize/reset presenceData.
	 */
	resetData = (
		defaultData: PresenceData = {
			details: "Viewing an unsupported page",
			largeImageKey:
				"https://cdn.rcd.gg/PreMiD/websites/W/Wikivoyage/assets/logo.png",
			startTimestamp: browsingTimestamp,
		}
	): void => {
		currentURL = new URL(document.location.href);
		currentPath = currentURL.pathname.replace(/^\/|\/$/g, "").split("/");
		presenceData = { ...defaultData };
	},
	/**
	 * Search for URL parameters.
	 * @param urlParam The parameter that you want to know about the value.
	 */
	getURLParam = (urlParam: string): string => {
		return currentURL.searchParams.get(urlParam);
	};

((): void => {
	if (currentURL.hostname === "www.wikivoyage.org")
		presenceData.details = "On the home page";
	else {
		let title: string;
		const actionResult = (): string =>
				getURLParam("action") || getURLParam("veaction"),
			[lang] = currentURL.hostname.split("."),
			titleFromURL = (): string => {
				return decodeURI(
					(currentPath[1] === "index.php"
						? getURLParam("title")
						: currentPath.slice(1).join("/")
					).replaceAll("_", " ")
				);
			};

		try {
			title = document.querySelector("h1:not(:empty)").textContent;
		} catch (e) {
			title = titleFromURL();
		}

		/**
		 * Returns details based on the namespace.
		 * @link https://en.wikivoyage.org/wiki/Special:PrefixIndex
		 */
		const namespaceDetails = (): string => {
			const details: { [index: string]: string } = {
				"-2": "Viewing a media",
				"-1": "Viewing a special page",
				0: "Reading an article",
				1: "Viewing a talk page",
				2: "Viewing a user page",
				3: "Viewing a user talk page",
				4: "Viewing a project page",
				5: "Viewing a project talk page",
				6: "Viewing a file",
				7: "Viewing a file talk page",
				8: "Viewing an interface page",
				9: "Viewing an interface talk page",
				10: "Viewing a template",
				11: "Viewing a template talk page",
				12: "Viewing a help page",
				13: "Viewing a help talk page",
				14: "Viewing a category",
				15: "Viewing a category talk page",
				828: "Viewing a module",
				829: "Viewing a module talk page",
				2300: "Viewing a gadget",
				2301: "Viewing a gadget talk page",
				2302: "Viewing a gadget definition page",
				2303: "Viewing a gadget definition talk page",
				2600: "Viewing a topic",
			};
			return (
				details[
					[...document.querySelector("body").classList]
						.find(v => /ns--?\d/.test(v))
						.slice(3)
				] || "Viewing a page"
			);
		};

		//
		// Important note:
		//
		// When checking for the current location, avoid using the URL.
		// The URL is going to be different in other languages.
		// Use the elements on the page instead.
		//

		if (
			(
				document.querySelector<HTMLAnchorElement>("#n-mainpage a") ??
				document.querySelector<HTMLAnchorElement>("#p-navigation a") ??
				document.querySelector<HTMLAnchorElement>(".mw-wiki-logo")
			).href === currentURL.href
		)
			presenceData.details = "On the main page";
		else if (document.querySelector("#wpLoginAttempt"))
			presenceData.details = "Logging in";
		else if (document.querySelector("#wpCreateaccount"))
			presenceData.details = "Creating an account";
		else if (document.querySelector(".searchresults")) {
			presenceData.details = "Searching for a page";
			presenceData.state =
				document.querySelector<HTMLInputElement>("input[type=search]").value;
		} else if (actionResult() === "history") {
			presenceData.details = "Viewing revision history";
			presenceData.state = titleFromURL();
		} else if (getURLParam("diff")) {
			presenceData.details = "Viewing difference between revisions";
			presenceData.state = titleFromURL();
		} else if (getURLParam("oldid")) {
			presenceData.details = "Viewing an old revision of a page";
			presenceData.state = titleFromURL();
		} else if (
			document.querySelector("#ca-ve-edit") ||
			getURLParam("veaction")
		) {
			presenceData.state = `${
				title.toLowerCase() === titleFromURL().toLowerCase()
					? `${title}`
					: `${title} (${titleFromURL()})`
			}`;
			updateCallback.function = (): void => {
				if (actionResult() === "edit" || actionResult() === "editsource")
					presenceData.details = "Editing a page";
				else presenceData.details = namespaceDetails();
			};
		} else if (actionResult() === "edit") {
			presenceData.details = document.querySelector("#ca-edit")
				? "Editing a page"
				: "Viewing source";
			presenceData.state = titleFromURL();
		} else {
			presenceData.details = namespaceDetails();
			presenceData.state = `${
				title.toLowerCase() === titleFromURL().toLowerCase()
					? `${title}`
					: `${title} (${titleFromURL()})`
			}`;
		}

		if (lang !== "en") {
			if (presenceData.state) presenceData.state += ` (${lang})`;
			else presenceData.details += ` (${lang})`;
		}
	}
})();

if (updateCallback.present) {
	const defaultData = { ...presenceData };
	presence.on("UpdateData", async () => {
		resetData(defaultData);
		updateCallback.function();
		presence.setActivity(presenceData);
	});
} else {
	presence.on("UpdateData", async () => {
		presence.setActivity(presenceData);
	});
}