refactor: replace signIn callback with signIn event, adjust getUserByEmail in adapter to check provider (#1223)

* refactor: replace signIn callback with signIn event, adjust getUserByEmail in adapter to check provider

* test: adjusting tests for adapter and events

* docs: add comments for unknown auth provider

* fix: missing dayjs import

packages/auth/callbacks.ts

@@ -1,5 +1,3 @@
-import { cookies } from "next/headers";
-import type { Adapter } from "@auth/core/adapters";
 import dayjs from "dayjs";
 import type { NextAuthConfig } from "next-auth";
 
@@ -9,9 +7,6 @@ import { eq, inArray } from "@homarr/db";
 import { groupMembers, groupPermissions, users } from "@homarr/db/schema/sqlite";
 import { getPermissionsWithChildren } from "@homarr/definitions";
 
-import { env } from "./env.mjs";
-import { expireDateAfter, generateSessionToken, sessionTokenCookieName } from "./session";
-
 export const getCurrentUserPermissionsAsync = async (db: Database, userId: string) => {
   const dbGroupMembers = await db.query.groupMembers.findMany({
     where: eq(groupMembers.userId, userId),
@@ -68,51 +63,6 @@ export const createSessionCallback = (db: Database): NextAuthCallbackOf<"session
   };
 };
 
-export const createSignInCallback =
-  (adapter: Adapter, db: Database, isCredentialsRequest: boolean): NextAuthCallbackOf<"signIn"> =>
-  async ({ user }) => {
-    if (!isCredentialsRequest) return true;
-
-    // https://github.com/nextauthjs/next-auth/issues/6106
-    if (!adapter.createSession || !user.id) {
-      return false;
-    }
-
-    const sessionToken = generateSessionToken();
-    const sessionExpires = expireDateAfter(env.AUTH_SESSION_EXPIRY_TIME);
-
-    await adapter.createSession({
-      sessionToken,
-      userId: user.id,
-      expires: sessionExpires,
-    });
-
-    cookies().set(sessionTokenCookieName, sessionToken, {
-      path: "/",
-      expires: sessionExpires,
-      httpOnly: true,
-      sameSite: "lax",
-      secure: true,
-    });
-
-    const dbUser = await db.query.users.findFirst({
-      where: eq(users.id, user.id),
-      columns: {
-        colorScheme: true,
-      },
-    });
-
-    if (!dbUser) return false;
-
-    // We use a cookie as localStorage is not shared with server (otherwise flickering would occur)
-    cookies().set("homarr-color-scheme", dbUser.colorScheme, {
-      path: "/",
-      expires: dayjs().add(1, "year").toDate(),
-    });
-
-    return true;
-  };
-
 type NextAuthCallbackRecord = Exclude<NextAuthConfig["callbacks"], undefined>;
 export type NextAuthCallbackOf<TKey extends keyof NextAuthCallbackRecord> = Exclude<
   NextAuthCallbackRecord[TKey],