"use server";

import { prisma } from "@/lib/prisma";
import { headers } from "next/headers";
import { auth } from "@/lib/auth";
import { redirect } from "next/navigation";
import { revalidatePath } from "next/cache";

async function requireAdmin() {
  const session = await auth.api.getSession({ headers: await headers() });
  if (!session || session.user.role !== "admin") throw new Error("Forbidden");
}

function slugify(str: string): string {
  const map: Record<string, string> = {
    а:"a",б:"b",в:"v",г:"g",д:"d",е:"e",ё:"yo",ж:"zh",з:"z",и:"i",й:"y",
    к:"k",л:"l",м:"m",н:"n",о:"o",п:"p",р:"r",с:"s",т:"t",у:"u",ф:"f",
    х:"kh",ц:"ts",ч:"ch",ш:"sh",щ:"shch",ъ:"",ы:"y",ь:"",э:"e",ю:"yu",я:"ya",
  };
  return str.toLowerCase()
    .replace(/[а-яё]/g, (c) => map[c] ?? c)
    .replace(/[^a-z0-9]+/g, "-")
    .replace(/^-|-$/g, "");
}

export async function createCourse(formData: FormData) {
  await requireAdmin();
  const title = formData.get("title") as string;
  const slug = (formData.get("slug") as string).trim() || slugify(title);
  const description = (formData.get("description") as string) || null;

  const course = await prisma.course.create({
    data: { title, slug, description },
  });

  revalidatePath("/admin/courses");
  redirect(`/admin/courses/${course.id}`);
}

export async function updateCourse(courseId: string, formData: FormData) {
  await requireAdmin();
  const title = formData.get("title") as string;
  const slug = formData.get("slug") as string;
  const description = (formData.get("description") as string) || null;
  const published = formData.get("published") === "true";
  const coverImage = (formData.get("coverImage") as string) || null;
  const categoryId = (formData.get("categoryId") as string) || null;

  await prisma.course.update({
    where: { id: courseId },
    data: { title, slug, description, published, coverImage, categoryId },
  });

  revalidatePath("/admin/courses");
  revalidatePath(`/admin/courses/${courseId}`);
}

export async function deleteCourse(courseId: string) {
  await requireAdmin();
  await prisma.course.delete({ where: { id: courseId } });
  revalidatePath("/admin/courses");
  redirect("/admin/courses");
}