"use server";

import { revalidatePath } from "next/cache";
import { z } from "zod";
import { getServerSession } from "@/lib/auth/guards";
import { prisma } from "@/lib/db";
import { LANGUAGES } from "@/lib/episodes/options";
import { VOICE_CATALOG } from "@/lib/ai/voices";

const VALID_LANGUAGES = new Set<string>(LANGUAGES.map((l) => l.code));
const VALID_VOICES = new Set<string>(VOICE_CATALOG.map((v) => v.id));

const preferencesSchema = z.object({
  defaultVoiceId: z.string().nullable().optional(),
  defaultLanguage: z.string().min(2).max(5).optional(),
  emailOnEpisodeReady: z.boolean().optional(),
  productEmails: z.boolean().optional(),
});

export type PreferencesInput = z.infer<typeof preferencesSchema>;

/**
 * Persist the current user's editor defaults and notification preferences.
 * Auth-checked; upserts the single per-user preferences row. Only validated,
 * known voice/language values are stored.
 */
export async function savePreferencesAction(
  input: PreferencesInput
): Promise<{ ok: boolean; error?: string }> {
  const session = await getServerSession();
  if (!session) return { ok: false, error: "You must be signed in." };

  const parsed = preferencesSchema.safeParse(input);
  if (!parsed.success) return { ok: false, error: "Invalid settings." };
  const data = parsed.data;

  if (data.defaultVoiceId && !VALID_VOICES.has(data.defaultVoiceId)) {
    return { ok: false, error: "Unknown voice." };
  }
  if (data.defaultLanguage && !VALID_LANGUAGES.has(data.defaultLanguage)) {
    return { ok: false, error: "Unsupported language." };
  }

  const userId = session.user.id;
  // Normalize "none"/empty voice to null.
  const defaultVoiceId =
    data.defaultVoiceId === undefined ? undefined : data.defaultVoiceId || null;

  await prisma.userPreferences.upsert({
    where: { userId },
    create: {
      userId,
      defaultVoiceId: defaultVoiceId ?? null,
      defaultLanguage: data.defaultLanguage ?? "en",
      emailOnEpisodeReady: data.emailOnEpisodeReady ?? true,
      productEmails: data.productEmails ?? true,
    },
    update: {
      ...(defaultVoiceId !== undefined ? { defaultVoiceId } : {}),
      ...(data.defaultLanguage !== undefined ? { defaultLanguage: data.defaultLanguage } : {}),
      ...(data.emailOnEpisodeReady !== undefined
        ? { emailOnEpisodeReady: data.emailOnEpisodeReady }
        : {}),
      ...(data.productEmails !== undefined ? { productEmails: data.productEmails } : {}),
    },
  });

  revalidatePath("/settings");
  return { ok: true };
}

/**
 * Permanently delete the current user's account. Auth-checked and gated by a
 * typed email confirmation that must match the session email. The User delete
 * cascades to sessions, accounts, episodes, series, usage and preferences. The
 * client signs out after a successful response.
 */
export interface ActiveSession {
  id: string;
  createdAt: string;
  expiresAt: string;
  ipAddress: string | null;
  userAgent: string | null;
  current: boolean;
}

/**
 * List the signed-in devices for the current user.
 *
 * Sessions are read straight from the DB (not the cookie cache) so a revoked
 * session disappears immediately rather than lingering for the 60s cache window.
 */
export async function listSessionsAction(): Promise<{
  ok: boolean;
  error?: string;
  sessions?: ActiveSession[];
}> {
  const session = await getServerSession();
  if (!session) return { ok: false, error: "You must be signed in." };

  const rows = await prisma.session.findMany({
    where: { userId: session.user.id, expiresAt: { gt: new Date() } },
    orderBy: { createdAt: "desc" },
    select: {
      id: true,
      token: true,
      createdAt: true,
      expiresAt: true,
      ipAddress: true,
      userAgent: true,
    },
  });

  return {
    ok: true,
    sessions: rows.map((r) => ({
      id: r.id,
      createdAt: r.createdAt.toISOString(),
      expiresAt: r.expiresAt.toISOString(),
      ipAddress: r.ipAddress,
      userAgent: r.userAgent,
      // Compare on the session token, never on the id: the token is what the
      // cookie actually carries, so this is the reliable "this device" marker.
      current: r.token === session.session.token,
    })),
  };
}

/**
 * Revoke one of the current user's sessions (sign out that device).
 *
 * Scoped by userId so a session id belonging to someone else can never be
 * revoked, and the current session is protected — signing yourself out from
 * here would be indistinguishable from a bug. Use the normal sign-out for that.
 */
export async function revokeSessionAction(
  sessionId: string
): Promise<{ ok: boolean; error?: string }> {
  const session = await getServerSession();
  if (!session) return { ok: false, error: "You must be signed in." };

  const target = await prisma.session.findFirst({
    where: { id: sessionId, userId: session.user.id },
    select: { id: true, token: true },
  });
  if (!target) return { ok: false, error: "Session not found." };
  if (target.token === session.session.token) {
    return { ok: false, error: "That's your current device — use Sign out instead." };
  }

  await prisma.session.delete({ where: { id: target.id } });
  revalidatePath("/settings");
  return { ok: true };
}

/** Sign out every other device, keeping the current one. */
export async function revokeOtherSessionsAction(): Promise<{
  ok: boolean;
  error?: string;
  count?: number;
}> {
  const session = await getServerSession();
  if (!session) return { ok: false, error: "You must be signed in." };

  const res = await prisma.session.deleteMany({
    where: { userId: session.user.id, token: { not: session.session.token } },
  });
  revalidatePath("/settings");
  return { ok: true, count: res.count };
}

/**
 * Export everything we hold about the current user, as JSON (GDPR access
 * request, self-serve).
 *
 * Deliberately excludes credentials: the `account` table holds password hashes
 * and OAuth tokens, and nothing there is user-facing data. Media is referenced
 * by storage key rather than inlined so the payload stays a reasonable size.
 */
export async function exportMyDataAction(): Promise<{
  ok: boolean;
  error?: string;
  json?: string;
}> {
  const session = await getServerSession();
  if (!session) return { ok: false, error: "You must be signed in." };
  const userId = session.user.id;

  const [user, preferences, episodes, series, subscriptions, usage, apiKeys, memberships] =
    await Promise.all([
      prisma.user.findUnique({
        where: { id: userId },
        select: {
          id: true,
          name: true,
          email: true,
          emailVerified: true,
          image: true,
          createdAt: true,
          updatedAt: true,
        },
      }),
      prisma.userPreferences.findUnique({ where: { userId } }),
      prisma.episode.findMany({
        where: { userId },
        orderBy: { createdAt: "desc" },
        select: {
          id: true,
          title: true,
          topic: true,
          tone: true,
          format: true,
          language: true,
          targetLengthMin: true,
          status: true,
          shareId: true,
          createdAt: true,
          script: { select: { content: true } },
          audioAsset: { select: { storageKey: true, durationSec: true, format: true } },
          coverArt: { select: { storageKey: true } },
          repurposed: { select: { type: true, content: true, createdAt: true } },
        },
      }),
      prisma.series.findMany({ where: { userId } }),
      prisma.subscription.findMany({
        where: { referenceId: userId },
        select: {
          plan: true,
          status: true,
          billingInterval: true,
          provider: true,
          periodStart: true,
          periodEnd: true,
          cancelAtPeriodEnd: true,
          createdAt: true,
        },
      }),
      prisma.usageRecord.findMany({ where: { ownerId: userId, ownerType: "user" } }),
      prisma.apiKey.findMany({
        where: { userId },
        select: { id: true, name: true, createdAt: true, revokedAt: true },
      }),
      prisma.member.findMany({
        where: { userId },
        select: { role: true, createdAt: true, organization: { select: { name: true } } },
      }),
    ]);

  const payload = {
    exportedAt: new Date().toISOString(),
    note: "Credentials and authentication tokens are intentionally excluded. Audio and cover art are referenced by storage key; download them from each episode page.",
    user,
    preferences,
    episodes,
    series,
    subscriptions,
    usage,
    apiKeys,
    memberships,
  };

  return { ok: true, json: JSON.stringify(payload, null, 2) };
}

export async function deleteAccountAction(
  confirmEmail: string
): Promise<{ ok: boolean; error?: string }> {
  const session = await getServerSession();
  if (!session) return { ok: false, error: "You must be signed in." };

  if (confirmEmail.trim().toLowerCase() !== session.user.email.toLowerCase()) {
    return { ok: false, error: "The email you typed doesn't match your account." };
  }

  // Deleting the User row cascades to all owned data via onDelete: Cascade.
  await prisma.user.delete({ where: { id: session.user.id } });
  return { ok: true };
}