import { getTranslations } from "next-intl/server";
import { redirect } from "next/navigation";
import Link from "next/link";
import { getSessionUser, canMutate } from "@/lib/session";
import { Card } from "@/components/ui/card";

/**
 * /settings — landing page for user/org-level configuration (Bug 35
 * intentionally landed billing here rather than at /billing because we
 * expect more settings categories: notifications, API keys, default
 * workspace templates, etc.). Currently lists a single category card;
 * the layout scales to a sidebar nav once there are 3+.
 *
 * Access: any authenticated user (the cards themselves gate further;
 * non-owner users would not see "Billing" as actionable, etc.).
 */
export async function generateMetadata() {
  const t = await getTranslations("common");
  return { title: t("settings") };
}

export default async function SettingsPage() {
  const user = await getSessionUser();
  if (!user) redirect("/login");
  const t = await getTranslations("settings");

  // Build the list of settings cards. Each entry has a stable key, a
  // route, and a visibility predicate. Phase 6 fix5: profile is
  // visible to every signed-in user (it's their own identity).
  // Billing stays gated behind canMutate.
  const sections: Array<{
    key: string;
    href: string;
    title: string;
    description: string;
    visible: boolean;
  }> = [
    {
      key: "profile",
      href: "/settings/profile",
      title: t("profileTitle"),
      description: t("profileDescription"),
      // Every signed-in user can edit their own first/last name.
      visible: true,
    },
    {
      key: "billing",
      href: "/settings/billing",
      title: t("billingTitle"),
      // Personal customers (B2C) don't have a VAT number; the
      // description shouldn't mention one. Same pattern used in the
      // form itself (label/field gating).
      description: user.isPersonal
        ? t("billingDescriptionPersonal")
        : t("billingDescription"),
      // Owners and platform admins can edit billing. `user` role
      // can't even view it — billing details aren't useful to them.
      visible: canMutate(user),
    },
  ];

  const visibleSections = sections.filter((s) => s.visible);

  return (
    <main className="max-w-4xl mx-auto px-6 py-8">
      <div className="mb-8 animate-in">
        <h1 className="font-display text-2xl font-semibold accent-rule">
          {t("title")}
        </h1>
        <p className="text-sm text-text-secondary mt-3">{t("subtitle")}</p>
      </div>

      {visibleSections.length === 0 && (
        <Card className="animate-in animate-in-delay-1">
          <p className="text-sm text-text-secondary">{t("nothingForYou")}</p>
        </Card>
      )}

      <div className="grid gap-3 animate-in animate-in-delay-1">
        {visibleSections.map((s) => (
          <Link
            key={s.key}
            href={s.href}
            className="block rounded-xl border border-border bg-surface-1 p-4 hover:border-text-secondary transition-colors"
          >
            <div className="font-medium text-text-primary">{s.title}</div>
            <div className="text-xs text-text-secondary mt-1">
              {s.description}
            </div>
          </Link>
        ))}
      </div>
    </main>
  );
}