import { db } from "../../../db/index";
import { courses } from "../../../db/schema";
import { eq } from "drizzle-orm";

export default defineEventHandler(async (event) => {
  const id = getRouterParam(event, "id")!;
  const body = await readBody(event);

  const course = await db.query.courses.findFirst({ where: eq(courses.id, id) });
  if (!course) throw createError({ statusCode: 404, message: "Course not found" });

  const updates: Partial<typeof courses.$inferInsert> = {};

  if (body.title !== undefined) {
    if (!body.title.trim()) throw createError({ statusCode: 400, message: "Title cannot be empty" });
    updates.title = body.title.trim();
  }
  if (body.subject !== undefined) {
    if (!body.subject.trim()) throw createError({ statusCode: 400, message: "Subject cannot be empty" });
    updates.subject = body.subject.trim();
  }

  if (Object.keys(updates).length === 0) {
    throw createError({ statusCode: 400, message: "Nothing to update" });
  }

  await db.update(courses).set(updates).where(eq(courses.id, id));

  return { ok: true };
});