import { db, notifications, users, recipes, eq } from "@epicure/db";
import { randomUUID } from "crypto";
import { sendPushNotification } from "./push";
import { sendEmail, notificationEmailHtml } from "./email";
import { getMessages, formatMessage } from "./i18n/server";
import { isNotificationCategoryEnabled, isEmailCategoryEnabled } from "./notification-prefs";

type NotificationType = "follow" | "comment" | "reply" | "reaction" | "rating" | "mention";

type CreateNotificationOpts = {
  userId: string;
  type: NotificationType;
  actorId: string;
  recipeId?: string;
  commentId?: string;
  /** Rating score (1-5), only relevant for type "rating" — included in the push/email copy. */
  score?: number;
};

export async function createNotification(opts: CreateNotificationOpts): Promise<void> {
  if (opts.userId === opts.actorId) return; // never notify yourself

  await db.insert(notifications).values({
    id: randomUUID(),
    userId: opts.userId,
    type: opts.type,
    actorId: opts.actorId,
    recipeId: opts.recipeId,
    commentId: opts.commentId,
  });

  // Push + email are best-effort side effects — never let a slow/failing SMTP
  // or push provider delay or break the caller (which already does `void
  // createNotification(...)`). Fire-and-forget from here too.
  void dispatchAlerts(opts).catch((err) => {
    console.error("[notifications] failed to dispatch push/email", err);
  });
}

async function dispatchAlerts(opts: CreateNotificationOpts): Promise<void> {
  const [actor, recipient, recipe] = await Promise.all([
    db.query.users.findFirst({
      where: eq(users.id, opts.actorId),
      columns: { name: true, username: true },
    }),
    db.query.users.findFirst({
      where: eq(users.id, opts.userId),
      columns: { email: true, locale: true },
    }),
    opts.recipeId
      ? db.query.recipes.findFirst({
          where: eq(recipes.id, opts.recipeId),
          columns: { title: true },
        })
      : Promise.resolve(undefined),
  ]);

  if (!actor || !recipient) return;

  const messages = getMessages(recipient.locale);
  const n = messages.notifications as Record<string, unknown>;
  const detail = (n["detail"] ?? {}) as Record<string, string>;
  const pushTitle = (n["pushTitle"] ?? {}) as Record<string, string>;

  const template = detail[opts.type] ?? (n[opts.type] as string | undefined);
  if (!template) return;

  const body = formatMessage(template, {
    name: actor.name,
    title: recipe?.title ?? "",
    stars: opts.score != null ? String(opts.score) : "",
  });
  const title = pushTitle[opts.type] ?? "Epicure";

  const url = opts.type === "follow"
    ? (actor.username ? `/u/${actor.username}` : "/")
    : opts.recipeId ? `/recipes/${opts.recipeId}` : "/";

  if (await isNotificationCategoryEnabled(opts.userId, opts.type)) {
    void sendPushNotification(opts.userId, { title, body, url }).catch((err) => {
      console.error("[notifications] push failed", err);
    });
  }

  if (recipient.email && (await isEmailCategoryEnabled(opts.userId, opts.type))) {
    const baseUrl = process.env["BETTER_AUTH_URL"] ?? "http://localhost:3000";
    void sendEmail({
      to: recipient.email,
      subject: title,
      html: notificationEmailHtml(title, body, `${baseUrl}${url}`),
    }).catch((err) => {
      console.error("[notifications] email failed", err);
    });
  }
}
