Added PWA support

public/sw.js

@@ -0,0 +1,80 @@
+const SHELL_CACHE = "music-pwa-shell-v1"
+const ASSET_CACHE = "music-pwa-assets-v1"
+const OFFLINE_PAGE = "/offline.html"
+const SHELL_ASSETS = [
+	OFFLINE_PAGE,
+	"/icons/pwa-192.png",
+	"/icons/pwa-512.png",
+	"/icons/pwa-maskable-512.png",
+	"/icons/apple-touch-icon.png",
+]
+const SHELL_ASSET_PATHS = new Set(SHELL_ASSETS)
+
+self.addEventListener("install", (event) => {
+	event.waitUntil(
+		caches
+			.open(SHELL_CACHE)
+			.then((cache) => cache.addAll(SHELL_ASSETS))
+			.then(() => self.skipWaiting()),
+	)
+})
+
+self.addEventListener("activate", (event) => {
+	event.waitUntil(
+		caches.keys().then(async (keys) => {
+			await Promise.all(
+				keys
+					.filter(
+						(key) =>
+							key.startsWith("music-pwa-") &&
+							key !== SHELL_CACHE &&
+							key !== ASSET_CACHE,
+					)
+					.map((key) => caches.delete(key)),
+			)
+			await self.clients.claim()
+		}),
+	)
+})
+
+self.addEventListener("fetch", (event) => {
+	const request = event.request
+	if (request.method !== "GET") return
+
+	const url = new URL(request.url)
+	if (url.origin !== self.location.origin) return
+
+	if (request.mode === "navigate") {
+		event.respondWith(
+			fetch(request).catch(async () => {
+				const offlinePage = await caches.match(OFFLINE_PAGE)
+				return offlinePage ?? Response.error()
+			}),
+		)
+		return
+	}
+
+	if (SHELL_ASSET_PATHS.has(url.pathname)) {
+		event.respondWith(
+		caches.match(request).then((cached) => cached ?? fetch(request)),
+		)
+		return
+	}
+
+	if (url.pathname.startsWith("/_nuxt/")) {
+		event.respondWith(
+			caches.open(ASSET_CACHE).then(async (cache) => {
+				const cached = await cache.match(request)
+				if (cached) return cached
+
+				const response = await fetch(request)
+				if (response.ok) {
+					await cache.put(request, response.clone())
+					const entries = await cache.keys()
+					if (entries.length > 100) await cache.delete(entries[0])
+				}
+				return response
+			}),
+		)
+	}
+})