add basic db schema + auth + oauth with osu

src/lib/server/auth.ts

@@ -4,17 +4,65 @@ import { sveltekitCookies } from 'better-auth/svelte-kit';
 import { env } from '$env/dynamic/private';
 import { getRequestEvent } from '$app/server';
 import { db } from '$lib/server/db';
+import { genericOAuth } from 'better-auth/plugins';
 
 export const auth = betterAuth({
 	baseURL: env.ORIGIN,
 	secret: env.BETTER_AUTH_SECRET,
 	database: drizzleAdapter(db, { provider: 'pg' }),
 	emailAndPassword: { enabled: true },
-	socialProviders: {
-		github: {
-			clientId: env.GITHUB_CLIENT_ID,
-			clientSecret: env.GITHUB_CLIENT_SECRET
-		}
-	},
-	plugins: [sveltekitCookies(getRequestEvent)] // make sure this is the last plugin in the array
+	plugins: [
+		genericOAuth({
+			config: [
+				{
+					providerId: 'osu',
+					clientId: env.OSU_CLIENT_ID!,
+					clientSecret: env.OSU_CLIENT_SECRET!,
+					authorizationUrl: 'https://osu.ppy.sh/oauth/authorize',
+					tokenUrl: 'https://osu.ppy.sh/oauth/token',
+					userInfoUrl: 'https://osu.ppy.sh/api/v2/me',
+					scopes: ['identify', 'public'],
+					pkce: false,
+					authentication: 'post',
+					redirectURI: 'http://localhost:5173/api/auth/oauth2/callback/osu',
+					getToken: async ({ code, redirectURI }) => {
+						const res = await fetch('https://osu.ppy.sh/oauth/token', {
+							method: 'POST',
+							headers: {
+								Accept: 'application/json',
+								'Content-Type': 'application/x-www-form-urlencoded'
+							},
+							body: new URLSearchParams({
+								client_id: env.OSU_CLIENT_ID!,
+								client_secret: env.OSU_CLIENT_SECRET!,
+								code,
+								grant_type: 'authorization_code',
+								redirect_uri: redirectURI
+							})
+						});
+						const data = await res.json();
+						if (!res.ok) {
+							console.error('osu! token exchange failed:', data);
+							throw new Error('Token exchange failed');
+						}
+						return {
+							accessToken: data.access_token,
+							refreshToken: data.refresh_token,
+							accessTokenExpiresAt: new Date(Date.now() + data.expires_in * 1000),
+							scopes: ['identify', 'public'],
+							raw: data
+						};
+					},
+					mapProfileToUser(profile) {
+						return {
+							name: profile.username,
+							image: profile.avatar_url,
+							email: `${profile.id}@osu.local`
+						};
+					}
+				}
+			]
+		}),
+		sveltekitCookies(getRequestEvent) // make sure this is the last plugin in the array
+	]
 });