import Link from "next/link";
import { redirect } from "next/navigation";
import { AuthError } from "next-auth";
import { platformAuth, platformSignIn } from "@/server/platform-auth";
import { Button } from "@/components/ui/button";
import { Input } from "@/components/ui/input";
import { Label } from "@/components/ui/label";
import { CertviaLogo } from "@/components/brand/certvia-logo";
import { PoweredByGefim } from "@/components/brand/powered-by-gefim";

/**
 * Getrennter Login für Plattform-Administratoren (Phase-1-Härtung Paket 2).
 * Eigene Auth-Domäne, kein Mandantenkontext. TOTP-Code ist ab eingerichteter MFA
 * erforderlich (Feld optional, damit der erste Login zur Einrichtung durchläuft).
 */
export default async function PlatformLoginPage({
  searchParams,
}: {
  searchParams: Promise<{ error?: string }>;
}) {
  const { error } = await searchParams;

  const session = await platformAuth();
  if (session?.user?.id) redirect("/admin");

  async function login(formData: FormData) {
    "use server";
    try {
      await platformSignIn("credentials", {
        email: formData.get("email"),
        password: formData.get("password"),
        token: formData.get("token"),
        redirectTo: "/admin",
      });
    } catch (err) {
      if (err instanceof AuthError) redirect("/platform/login?error=1");
      throw err; // NEXT_REDIRECT eines erfolgreichen signIn muss durchlaufen
    }
  }

  return (
    <main className="flex flex-1 items-center justify-center p-6">
      <div className="shadow-card w-full max-w-sm rounded-2xl border bg-card p-8">
        <CertviaLogo variant="lockup" theme="dark" height={38} />
        <p className="mt-4 font-heading text-lg font-semibold">Plattform-Administration</p>
        <h2 className="mt-1 text-sm font-normal text-muted-foreground">
          Betreiberzugang — getrennt vom Mandanten-Login
        </h2>

        {error && (
          <p
            role="alert"
            className="mt-4 rounded-lg bg-[rgba(255,107,107,0.16)] px-3 py-2 text-sm text-[var(--risk)]"
          >
            Anmeldung fehlgeschlagen. Bitte E-Mail, Passwort und — falls MFA eingerichtet — den 6-stelligen Code prüfen.
          </p>
        )}

        <form action={login} className="mt-6 space-y-4">
          <div>
            <Label htmlFor="email">E-Mail</Label>
            <Input id="email" name="email" type="email" required autoComplete="email" className="mt-1" />
          </div>
          <div>
            <Label htmlFor="password">Passwort</Label>
            <Input id="password" name="password" type="password" required autoComplete="current-password" className="mt-1" />
          </div>
          <div>
            <Label htmlFor="token">MFA-Code (falls eingerichtet)</Label>
            <Input
              id="token"
              name="token"
              inputMode="numeric"
              autoComplete="one-time-code"
              placeholder="6-stelliger Code oder Recovery-Code"
              className="mt-1"
            />
          </div>
          <Button type="submit" className="w-full">Anmelden</Button>
        </form>

        <p className="mt-4 text-center text-[12.5px]">
          <Link href="/forgot-password?domain=platform" className="text-muted-foreground hover:text-foreground">
            Passwort vergessen?
          </Link>
        </p>

        <PoweredByGefim className="mt-7 border-t border-[var(--panel-brd)] pt-4" />
      </div>
    </main>
  );
}