import Link from "next/link";
import { notFound } from "next/navigation";
import { getTranslations } from "next-intl/server";
import { ArrowLeft, History, Boxes, Users, DatabaseBackup, ShieldCheck, Download } from "lucide-react";
import { prisma } from "@/server/db";
import { platformAuth } from "@/server/platform-auth";
import { Button } from "@/components/ui/button";
import { PageHead, Pill } from "@/components/mockup-ui";
import { MODULES } from "@/lib/modules";
import { setTenantStatus, toggleTenantModule, setTenantMfaRequired, setTenantLocale } from "@/server/actions/admin";
import { resolveMfaRequired } from "@/lib/mfa-policy";
import { createTenantUser, updateTenantUser, setTenantUserRoles, setTenantUserStatus } from "@/server/actions/platform-users";
import { enqueueRestore, enqueueExport, enqueueDsgvoExport } from "@/server/actions/backup-admin";
import { listSnapshots } from "@/server/backup/export";
import { getBackupStore } from "@/server/storage/backup-store";
import type { BackupManifest } from "@/server/backup/serialization";
import { Modal } from "@/components/modal";
import { UserTable } from "@/components/user-table";
import { UserCreateForm, UserEditForm } from "@/components/user-forms";
import { AuditTrailModal, type AuditRow } from "@/components/audit-trail";
import { RestoreModalBody, ExportModalBody, DsgvoModalBody, type SnapshotOption, type SubjectOption } from "@/components/backup-admin-panel";
import { TrialAdminCard } from "@/components/trial/trial-admin-card";

const STATUS_TONE: Record<string, "ok" | "warn" | "mut"> = { ACTIVE: "ok", SUSPENDED: "warn", ARCHIVED: "mut" };

export default async function AdminTenantPage({
  params,
  searchParams,
}: {
  params: Promise<{ id: string }>;
  searchParams: Promise<{ new?: string; edit?: string; audit?: string; modules?: string; users?: string; restore?: string; export?: string; dsgvo?: string; trial?: string; invited?: string; trialDone?: string }>;
}) {
  // Zugriff (Plattform-Session + MFA) wird im (platform)/layout.tsx erzwungen.
  const { id } = await params;
  const sp = await searchParams;
  const t = await getTranslations("admin");

  const tenant = await prisma.tenant.findUnique({
    where: { id },
    include: {
      settings: true,
      modules: true,
      roles: { select: { id: true, key: true, name: true }, orderBy: { name: "asc" } },
      users: {
        select: { id: true, name: true, email: true, status: true, identityId: true, userRoles: { select: { role: { select: { id: true, name: true } } } } },
        orderBy: { createdAt: "asc" },
      },
    },
  });
  if (!tenant) notFound();

  const STATUS_LABEL: Record<string, string> = { ACTIVE: t("statusActive"), SUSPENDED: t("statusSuspended"), ARCHIVED: t("statusArchived") };

  const roleOptions = tenant.roles.map((r) => ({ id: r.id, name: r.name }));
  const tableUsers = tenant.users.map((u) => ({
    id: u.id, name: u.name, email: u.email, status: u.status, roleNames: u.userRoles.map((ur) => ur.role.name),
  }));
  const editUser = sp.edit ? tenant.users.find((u) => u.id === sp.edit) : null;
  const base = `/admin/${tenant.id}`;

  const moduleState = new Map(tenant.modules.map((m) => [m.moduleKey, m.enabled]));
  const isOn = (key: string) => moduleState.get(key) ?? true;

  const s = tenant.settings;

  // Hauptkontakt (bestätigte Entscheidung): AUS den tenant-admin-Usern ABLEITEN —
  // keine eigenen TenantSettings-Felder, keine Migration. Aktive Mitglieder mit der
  // Standardrolle "tenant-admin" (RBAC-Key) gelten als Hauptkontakt.
  const adminRoleIds = new Set(tenant.roles.filter((r) => r.key === "tenant-admin").map((r) => r.id));
  const mainContacts = tenant.users.filter(
    (u) => u.status === "ACTIVE" && u.userRoles.some((ur) => adminRoleIds.has(ur.role.id)),
  );

  // Audit-Trail dieses Mandanten (nur laden, wenn Popup offen). Als Superadmin
  // cross-tenant über den Owner-Client, explizit auf diesen Mandanten gefiltert.
  let auditRows: AuditRow[] = [];
  let auditActors: Record<string, string> = {};
  if (sp.audit) {
    auditRows = await prisma.auditLog.findMany({
      where: { tenantId: id },
      orderBy: { createdAt: "desc" },
      take: 200,
      select: { id: true, createdAt: true, actorId: true, action: true, entity: true, entityId: true, scope: true },
    });
    const actorIds = [...new Set(auditRows.map((r) => r.actorId).filter(Boolean))] as string[];
    if (actorIds.length) {
      const users = await prisma.user.findMany({ where: { id: { in: actorIds } }, select: { id: true, name: true } });
      auditActors = Object.fromEntries(users.map((u) => [u.id, u.name]));
    }
  }

  const usersBase = `${base}?users=1`;

  // ── Datensicherung & DSGVO (Betreiber-Portal) ──────────────────────────────
  // Nur Voll-Admins dürfen Restore/Export/DSGVO auslösen; MFA-Status steuert das
  // Step-up-Feld. Die Session ist im (platform)/layout bereits erzwungen.
  const platformSession = await platformAuth();
  const currentAdmin = platformSession?.user?.id
    ? await prisma.platformAdmin.findUnique({ where: { id: platformSession.user.id }, select: { role: true, mfaEnrolledAt: true } })
    : null;
  const isFullAdmin = currentAdmin?.role === "full";
  const adminMfaEnrolled = currentAdmin?.mfaEnrolledAt != null;

  // Sicherungspunkte + Dry-run-Vorschau (Manifest je Snapshot, nur wenn Popup offen).
  // FAIL-SAFE: Ein nicht erreichbarer Sicherungsspeicher (S3/Garage nicht konfiguriert,
  // Bucket fehlt, Creds falsch) darf die Betreiber-Konsole NICHT auf eine Fehlerseite
  // werfen — die Liste bleibt dann leer und das Popup zeigt einen Hinweis.
  const snapshotOptions: SnapshotOption[] = [];
  let snapshotStoreError = false;
  if (isFullAdmin && (sp.restore || sp.dsgvo)) {
    try {
      const store = await getBackupStore();
      const ids = await listSnapshots(id);
      for (const snapshotId of ids.reverse()) {
        const raw = await store.get(`${id}/backups/${snapshotId}/manifest.json`);
        let manifest: BackupManifest | null = null;
        if (raw) { try { manifest = JSON.parse(raw.toString("utf8")) as BackupManifest; } catch { manifest = null; } }
        snapshotOptions.push({
          snapshotId,
          snapshotAt: manifest?.snapshotAt ?? null,
          totalRows: manifest?.totalRows ?? null,
          artifactTenantSlug: manifest?.tenantSlug ?? null,
          tenantMismatch: manifest ? manifest.tenantId !== id : false,
          tables: (manifest?.tables ?? []).filter((tm) => tm.rowCount > 0).map((tm) => ({ model: tm.model, rows: tm.rowCount })).sort((a, b) => b.rows - a.rows),
        });
      }
    } catch (err) {
      snapshotStoreError = true;
      console.error("[backup] Sicherungsspeicher nicht erreichbar (list/get):", err);
    }
  }

  // Betroffene Personen (für Per-Person-DSGVO-Auskunft).
  const subjectOptions: SubjectOption[] = tenant.users.map((u) => ({
    identityId: u.identityId,
    label: `${u.name} · ${u.email}`,
  })).filter((s) => s.identityId);

  // Letzte Jobs dieses Mandanten (Status/Ergebnis-Anzeige).
  const backupJobs = isFullAdmin
    ? await prisma.backupJob.findMany({
        where: { tenantId: id },
        orderBy: { createdAt: "desc" },
        take: 8,
        select: { id: true, kind: true, status: true, snapshotId: true, error: true, createdAt: true, downloadToken: true, downloadExpiresAt: true },
      })
    : [];
  const jobKindLabel: Record<string, string> = { tenant_restore: "Restore", tenant_export: "Export", dsgvo_export: "DSGVO-Export" };
  const jobStatusTone: Record<string, "ok" | "warn" | "mut"> = { done: "ok", queued: "warn", running: "warn", failed: "mut" };

  return (
    <main className="flex-1 p-6">
      <Link href="/admin" className="inline-flex items-center gap-1.5 text-[12.5px] font-semibold text-muted-foreground hover:text-foreground">
        <ArrowLeft className="size-4" /> {t("backToOverview")}
      </Link>
      <div className="mt-3">
        <PageHead
          crumb={t("crumb")}
          title={tenant.name}
          sub={t("sub", { slug: tenant.slug, sector: tenant.sector ? ` · ${tenant.sector}` : "" })}
          actions={<Pill tone={STATUS_TONE[tenant.status]}>{STATUS_LABEL[tenant.status]}</Pill>}
        />
      </div>

      <div className="mt-4 grid gap-5 lg:grid-cols-[1fr_320px]">
        {/* Hauptfenster: Stammdaten + Hauptkontakt + Verwaltung (Module/Benutzer als Popup) */}
        <div className="space-y-5">
          {/* Stammdaten (aus TenantSettings — einzige Quelle) */}
          <div className="shadow-card rounded-xl border bg-card p-5">
            <p className="mb-1 font-heading text-sm font-semibold">{t("masterDataTitle")}</p>
            <p className="mb-3 text-[12px] text-muted-foreground">{t("masterDataHint")}</p>
            <dl className="grid gap-x-6 gap-y-2.5 sm:grid-cols-2">
              <Field label={t("orgName")} value={s?.orgName ?? tenant.name} />
              <Field label={t("orgShort")} value={s?.orgShort ?? tenant.short} empty={t("notSet")} />
              <Field label={t("slug")} value={tenant.slug} />
              <Field label={t("sector")} value={s?.sector ?? tenant.sector} empty={t("notSet")} />
              <Field label={t("address")} value={s?.address} empty={t("notSet")} />
              <Field label={t("phone")} value={s?.phone} empty={t("notSet")} />
              <Field label={t("email")} value={s?.email} empty={t("notSet")} />
              <Field label={t("status")} value={STATUS_LABEL[tenant.status]} />
            </dl>
          </div>

          {/* Hauptkontakt (abgeleitet aus tenant-admin) */}
          <div className="shadow-card rounded-xl border bg-card p-5">
            <p className="mb-1 font-heading text-sm font-semibold">{t("mainContactTitle")}</p>
            <p className="mb-3 text-[12px] text-muted-foreground">{t("mainContactHint")}</p>
            {mainContacts.length ? (
              <ul className="space-y-2">
                {mainContacts.map((c) => (
                  <li key={c.id} className="flex items-center justify-between gap-3 rounded-lg border bg-muted/40 px-3 py-2">
                    <div>
                      <p className="text-sm font-medium">{c.name}</p>
                      <p className="text-[12px] text-muted-foreground">{c.email}</p>
                    </div>
                  </li>
                ))}
              </ul>
            ) : (
              <p className="text-[12.5px] text-muted-foreground">{t("mainContactNone")}</p>
            )}
          </div>

          {/* Verwaltung: Module & Benutzer als Popup (bestehendes ?param/<Modal>-Muster) */}
          <div className="shadow-card rounded-xl border bg-card p-5">
            <p className="mb-1 font-heading text-sm font-semibold">{t("manageTitle")}</p>
            <p className="mb-3 text-[12px] text-muted-foreground">{t("manageHint")}</p>
            <div className="flex flex-wrap gap-2">
              <Link href={`${base}?modules=1`} scroll={false}>
                <Button variant="outline" size="sm" className="gap-2"><Boxes className="size-4" /> {t("manageModules")}</Button>
              </Link>
              <Link href={usersBase} scroll={false}>
                <Button variant="outline" size="sm" className="gap-2"><Users className="size-4" /> {t("manageUsers")} · {t("usersCount", { count: tenant.users.length })}</Button>
              </Link>
            </div>
          </div>
        </div>

        <div className="space-y-5">
          {/* L15 Testphase: Enddatum, Umwandlung, Beenden, Löschung (Bestätigung + Plattform-Audit) */}
          <TrialAdminCard
            tenant={tenant}
            isFullAdmin={isFullAdmin}
            base={base}
            op={sp.trial === "created" ? undefined : sp.trial}
            notice={sp.trial === "created" ? (sp.invited ? "invited" : "created") : sp.trialDone ? "done" : null}
          />

          {/* Lebenszyklus */}
          <div className="shadow-card rounded-xl border bg-card p-5">
            <p className="mb-3 font-heading text-sm font-semibold">{t("lifecycleTitle")}</p>
            <div className="space-y-2">
              <form action={setTenantStatus.bind(null, tenant.id, "ACTIVE")}>
                <Button type="submit" variant={tenant.status === "ACTIVE" ? "secondary" : "outline"} size="sm" className="w-full justify-center" disabled={tenant.status === "ACTIVE"}>{t("lifecycleActivate")}</Button>
              </form>
              <form action={setTenantStatus.bind(null, tenant.id, "SUSPENDED")}>
                <Button type="submit" variant="outline" size="sm" className="w-full justify-center" disabled={tenant.status === "SUSPENDED"}>{t("lifecycleSuspend")}</Button>
              </form>
              <form action={setTenantStatus.bind(null, tenant.id, "ARCHIVED")}>
                <Button type="submit" variant="outline" size="sm" className="w-full justify-center" disabled={tenant.status === "ARCHIVED"}>{t("lifecycleArchive")}</Button>
              </form>
            </div>
            <p className="mt-3 text-[11px] text-muted-foreground">{t("lifecycleNote")}</p>
          </div>

          {/* SEC3-a: MFA-Pflicht je Mandant (nur Superadmin) */}
          <div className="shadow-card rounded-xl border bg-card p-5">
            <p className="mb-1 font-heading text-sm font-semibold">{t("mfaTitle")}</p>
            <p className="mb-3 text-[12px] text-muted-foreground">{t("mfaHint", { state: resolveMfaRequired(s?.securityPolicy) ? t("mfaStateOn") : t("mfaStateOff") })}</p>
            <div className="space-y-2">
              <form action={setTenantMfaRequired.bind(null, tenant.id, true)}>
                <Button type="submit" variant={resolveMfaRequired(s?.securityPolicy) ? "secondary" : "outline"} size="sm" className="w-full justify-center" disabled={resolveMfaRequired(s?.securityPolicy)}>{t("mfaActivate")}</Button>
              </form>
              <form action={setTenantMfaRequired.bind(null, tenant.id, false)}>
                <Button type="submit" variant={!resolveMfaRequired(s?.securityPolicy) ? "secondary" : "outline"} size="sm" className="w-full justify-center" disabled={!resolveMfaRequired(s?.securityPolicy)}>{t("mfaDeactivate")}</Button>
              </form>
            </div>
          </div>

          {/* Standardsprache je Mandant (Benachrichtigungen/Dokumente) */}
          <div className="shadow-card rounded-xl border bg-card p-5">
            <p className="mb-1 font-heading text-sm font-semibold">{t("localeTitle")}</p>
            <p className="mb-3 text-[12px] text-muted-foreground">{t("localeHint", { lang: s?.locale === "en" ? t("localeEn") : t("localeDe") })}</p>
            <div className="space-y-2">
              <form action={setTenantLocale.bind(null, tenant.id, "de")}>
                <Button type="submit" variant={(s?.locale ?? "de") === "de" ? "secondary" : "outline"} size="sm" className="w-full justify-center" disabled={(s?.locale ?? "de") === "de"}>{t("localeDe")}</Button>
              </form>
              <form action={setTenantLocale.bind(null, tenant.id, "en")}>
                <Button type="submit" variant={s?.locale === "en" ? "secondary" : "outline"} size="sm" className="w-full justify-center" disabled={s?.locale === "en"}>{t("localeEn")}</Button>
              </form>
            </div>
          </div>

          {/* Audit-Trail (Aktivitätsprotokoll dieses Mandanten) — Popup wie gehabt */}
          <div className="shadow-card rounded-xl border bg-card p-5">
            <p className="mb-1 font-heading text-sm font-semibold">{t("auditTitle")}</p>
            <p className="mb-3 text-[12px] text-muted-foreground">{t("auditHint")}</p>
            <Link href={`${base}?audit=1`} scroll={false}>
              <Button variant="outline" size="sm" className="w-full justify-center gap-2"><History className="size-4" /> {t("auditView")}</Button>
            </Link>
          </div>

          {/* Datensicherung & DSGVO (nur Voll-Admin) — Restore ist DESTRUKTIV */}
          {isFullAdmin && (
            <div className="shadow-card rounded-xl border bg-card p-5">
              <p className="mb-1 font-heading text-sm font-semibold">Datensicherung & DSGVO</p>
              <p className="mb-3 text-[12px] text-muted-foreground">Betreiber-Aktionen: Sicherung erstellen, Mandant wiederherstellen (destruktiv, MFA + Bestätigung), DSGVO-Paket zustellen.</p>
              <div className="space-y-2">
                <Link href={`${base}?export=1`} scroll={false}>
                  <Button variant="outline" size="sm" className="w-full justify-center gap-2"><DatabaseBackup className="size-4" /> Export jetzt</Button>
                </Link>
                <Link href={`${base}?restore=1`} scroll={false}>
                  <Button variant="outline" size="sm" className="w-full justify-center gap-2 border-destructive/40 text-destructive hover:bg-destructive/10"><ShieldCheck className="size-4" /> Wiederherstellen…</Button>
                </Link>
                <Link href={`${base}?dsgvo=1`} scroll={false}>
                  <Button variant="outline" size="sm" className="w-full justify-center gap-2"><Download className="size-4" /> DSGVO-Export</Button>
                </Link>
              </div>
              {backupJobs.length > 0 && (
                <div className="mt-3 border-t pt-3">
                  <p className="mb-1.5 text-[11px] font-medium uppercase tracking-wide text-muted-foreground">Letzte Jobs</p>
                  <ul className="space-y-1.5">
                    {backupJobs.map((j) => {
                      const linkLive = j.kind === "dsgvo_export" && j.status === "done" && !!j.downloadToken && isDownloadLive(j.downloadExpiresAt);
                      return (
                        <li key={j.id} className="flex items-center justify-between gap-2 text-[12px]">
                          <span className="flex items-center gap-2">
                            <Pill tone={jobStatusTone[j.status] ?? "mut"}>{j.status}</Pill>
                            <span>{jobKindLabel[j.kind] ?? j.kind}</span>
                          </span>
                          {linkLive ? (
                            <a href={`/api/platform/dsgvo/${j.downloadToken}`} className="font-medium text-primary hover:underline">Download</a>
                          ) : (
                            <span className="text-muted-foreground">{new Date(j.createdAt).toLocaleString()}</span>
                          )}
                        </li>
                      );
                    })}
                  </ul>
                  {backupJobs.some((j) => j.status === "failed") && (
                    <p className="mt-1.5 text-[11px] text-destructive">{backupJobs.find((j) => j.status === "failed")?.error}</p>
                  )}
                </div>
              )}
            </div>
          )}
        </div>
      </div>

      {/* Module → Popup (?modules=1) */}
      {sp.modules && (
        <Modal title={t("modulesTitle")} sub={t("modulesModalSub", { name: tenant.name })} closeHref={base} closeLabel={t("close")}>
          <div className="p-5">
            <p className="mb-3 text-[12px] text-muted-foreground">{t("modulesHint")}</p>
            <div className="divide-y">
              {MODULES.map((m) => {
                const on = isOn(m.key);
                return (
                  <div key={m.key} className="flex items-center justify-between gap-3 py-2.5">
                    <div>
                      <p className="text-sm font-medium">{m.name}</p>
                      <p className="text-[11px] text-muted-foreground">{m.href ?? m.key}</p>
                    </div>
                    <div className="flex items-center gap-2">
                      <Pill tone={on ? "ok" : "mut"}>{on ? t("moduleActive") : t("moduleInactive")}</Pill>
                      <form action={toggleTenantModule.bind(null, tenant.id, m.key, !on)}>
                        <Button type="submit" size="sm" variant="outline">{on ? t("moduleDeactivate") : t("moduleActivate")}</Button>
                      </form>
                    </div>
                  </div>
                );
              })}
            </div>
          </div>
        </Modal>
      )}

      {/* Benutzer → Popup (?users=1); Anlegen/Bearbeiten laufen verschachtelt (?new/?edit) */}
      {sp.users && (
        <Modal title={`${t("manageUsers")} — ${tenant.name}`} sub={t("usersModalSub", { name: tenant.name })} closeHref={base} closeLabel={t("close")}>
          <div className="p-5">
            <UserTable users={tableUsers} newHref={`${usersBase}&new=1`} editHref={(uid) => `${usersBase}&edit=${uid}`} />
          </div>
        </Modal>
      )}

      {sp.users && sp.new && (
        <Modal title={t("userCreate")} sub={t("userCreateSub", { name: tenant.name })} closeHref={usersBase} closeLabel={t("close")}>
          <UserCreateForm action={createTenantUser.bind(null, tenant.id)} roles={roleOptions} closeHref={usersBase} />
        </Modal>
      )}

      {sp.users && editUser && (
        <Modal title={t("userEdit", { name: editUser.name })} sub={editUser.email} closeHref={usersBase} closeLabel={t("close")}>
          <UserEditForm
            user={{
              id: editUser.id, name: editUser.name, email: editUser.email, status: editUser.status,
              roleIds: editUser.userRoles.map((ur) => ur.role.id),
            }}
            roles={roleOptions}
            updateAction={updateTenantUser.bind(null, tenant.id, editUser.id)}
            rolesAction={setTenantUserRoles.bind(null, tenant.id, editUser.id)}
            statusAction={setTenantUserStatus.bind(null, tenant.id, editUser.id, editUser.status === "ACTIVE" ? "DEACTIVATED" : "ACTIVE")}
          />
        </Modal>
      )}

      {sp.audit && (
        <AuditTrailModal rows={auditRows} actorNames={auditActors} closeHref={base} sub={t("auditSub", { name: tenant.name })} />
      )}

      {/* Export jetzt → Popup (?export=1) */}
      {isFullAdmin && sp.export && (
        <Modal title="Export jetzt" sub={`On-demand-Sicherung — ${tenant.name}`} closeHref={base} closeLabel={t("close")}>
          <ExportModalBody tenantId={tenant.id} action={enqueueExport} mfaEnrolled={adminMfaEnrolled} />
        </Modal>
      )}

      {/* Portal-Restore → Popup (?restore=1) — destruktiv */}
      {isFullAdmin && sp.restore && (
        <Modal title="Mandant wiederherstellen" sub={`Destruktiver Restore — ${tenant.name} (${tenant.slug})`} closeHref={base} closeLabel={t("close")}>
          <RestoreModalBody tenantId={tenant.id} tenantSlug={tenant.slug} snapshots={snapshotOptions} action={enqueueRestore} mfaEnrolled={adminMfaEnrolled} storeError={snapshotStoreError} />
        </Modal>
      )}

      {/* DSGVO-Export → Popup (?dsgvo=1) */}
      {isFullAdmin && sp.dsgvo && (
        <Modal title="DSGVO-Export" sub={`Auskunft/Portabilität — ${tenant.name}`} closeHref={base} closeLabel={t("close")}>
          <DsgvoModalBody tenantId={tenant.id} action={enqueueDsgvoExport} subjects={subjectOptions} mfaEnrolled={adminMfaEnrolled} />
        </Modal>
      )}
    </main>
  );
}

/** TTL-Prüfung des DSGVO-Download-Links (Modul-Scope: hält die Render-Funktion rein). */
function isDownloadLive(expiresAt: Date | null): boolean {
  return !!expiresAt && expiresAt.getTime() > Date.now();
}

/** Kleines Stammdaten-Feld (Label + Wert, Fallback bei leer). */
function Field({ label, value, empty }: { label: string; value?: string | null; empty?: string }) {
  return (
    <div>
      <dt className="text-[11px] font-medium uppercase tracking-wide text-muted-foreground">{label}</dt>
      <dd className="text-[13.5px]">{value && value.trim() ? value : (empty ?? "—")}</dd>
    </div>
  );
}