feat: add Last.fm provider integration with configuration and SVG asset

.github/ISSUE_TEMPLATE/2_bug_provider.yml

@@ -63,6 +63,7 @@ body:
         - "Frontegg"
         - "Keycloak"
         - "Kinde"
+        - "Last.fm"
         - "Line"
         - "LinkedIn"
         - "Logto"

packages/core/src/providers/lastfm.ts

@@ -0,0 +1,94 @@
+/**
+ * <div class="provider" style={{backgroundColor: "#d51007", display: "flex", justifyContent: "space-between", color: "#fff", padding: 16}}>
+ * <span>Built-in <b>Last.fm</b> integration.</span>
+ * <a href="https://www.last.fm/">
+ *   <img style={{display: "block"}} src="https://authjs.dev/img/providers/lastfm.svg" height="48" />
+ * </a>
+ * </div>
+ *
+ * @module providers/lastfm
+ */
+import type { OAuthConfig, OAuthUserConfig } from "./index.js"
+
+export interface LastFMProfile {
+  name: string
+  realname?: string
+  url: string
+  image: { "#text": string; size: string }[]
+}
+
+/**
+ * Add Last.fm login to your page.
+ *
+ * ### Setup
+ *
+ * #### Callback URL
+ * ```
+ * https://example.com/api/auth/callback/lastfm
+ * ```
+ *
+ * #### Configuration
+ *```ts
+ * import { Auth } from "@auth/core"
+ * import LastFM from "@auth/core/providers/lastfm"
+ *
+ * const request = new Request(origin)
+ * const response = await Auth(request, {
+ *   providers: [
+ *     LastFM({
+ *       clientId: LASTFM_API_KEY,
+ *       clientSecret: LASTFM_SHARED_SECRET,
+ *     }),
+ *   ],
+ * })
+ * ```
+ *
+ * ### Resources
+ *
+ * - [Last.fm API docs](https://www.last.fm/api/authentication)
+ * - [Create an API account](https://www.last.fm/api/account/create)
+ *
+ * ### Notes
+ *
+ * Last.fm uses a custom authentication flow that is *similar* to OAuth, but requires generating an `api_sig` with your API secret to exchange the temporary token for a session key.
+ *
+ * :::info
+ *
+ * This provider assumes you handle the session key exchange manually or through a custom callback, since Auth.js does not support MD5 hashing without adding dependencies.
+ *
+ * :::
+ */
+export default function LastFM<P extends LastFMProfile>(
+  options: OAuthUserConfig<P>
+): OAuthConfig<P> {
+  return {
+    id: "lastfm",
+    name: "Last.fm",
+    type: "oauth",
+    authorization: {
+      url: "https://www.last.fm/api/auth",
+      params: { api_key: options.clientId },
+    },
+    token: "https://ws.audioscrobbler.com/2.0/?method=auth.getSession",
+    userinfo: {
+      url: "https://ws.audioscrobbler.com/2.0/?method=user.getInfo&format=json",
+      async request({ tokens }) {
+        const res = await fetch(
+          `https://ws.audioscrobbler.com/2.0/?method=user.getInfo&api_key=${options.clientId}&sk=${tokens.access_token}&format=json`
+        )
+        const { user } = await res.json()
+        return user
+      },
+    },
+    profile(profile) {
+      return {
+        id: profile.name,
+        name: profile.realname || profile.name,
+        email: null,
+        image: profile.image?.find((img) => img.size === "large")?.["#text"],
+      }
+    },
+    style: { brandColor: "#d51007" },
+    options,
+  }
+}