Split server code from client code

import {action, cache, redirect} from "@solidjs/router";
import {validate} from "email-validator";
import * as db from "../../../database.js";
import * as auth from "../../../auth.js";
import {deleteCookie, getCookie} from "vinxi/http";

export const signUp = action(async (formData) => {
    "use server";
    const email = formData.get("email");
    if (email && validate(email)) {
        const user = await db.getUserByEmail(email);
        if (user) {
            return new Error("Email address already in use.");
        } else {
            const code = auth.randomCode();
            // send email code
            const verifyState = auth.encryptPayload({email, code, intent: "signup"});
            return redirect(`/verify?state=${verifyState}`);
        }
    } else {
        return new Error("Invalid email address.");
    }
}, "sign-up");

export const checkSession = cache(async () => {
    "use server";
    const sessionCookie = getCookie("session");
    if (sessionCookie) {
        try {
            const sessionData = auth.decryptPayload(sessionCookie);
            if (sessionData.state === auth.SessionState.Authenticated && sessionData.userId) {
                const user = await db.getUserById(sessionData.userId);
                if (user) {
                    return redirect("/app");
                }
            }
            throw new Error();
        } catch {
            deleteCookie("session");
        }
    }
}, "check-session");