import { Router } from "@oak/oak";
import { authMiddleware } from "../middleware/auth.ts";
import {
  createAttachment,
  getAttachment,
} from "../services/attachment-service.ts";
import { APIErrorCode, APIException } from "../model/interfaces.ts";
import {
  ATTACHMENTS_DIR,
  serveUploadedFile,
  validateImageUpload,
} from "../lib/upload.ts";

const router = new Router();

router.post("/api/attachments", authMiddleware, async (ctx) => {
  const contentType = ctx.request.headers.get("content-type") ?? "";
  if (!contentType.includes("multipart/form-data")) {
    throw new APIException(
      APIErrorCode.BAD_REQUEST,
      400,
      "Expected multipart/form-data",
    );
  }

  const body = await ctx.request.body.formData();
  const file = body.get("file");

  if (!(file instanceof File)) {
    throw new APIException(APIErrorCode.BAD_REQUEST, 400, "Missing file");
  }

  const data = new Uint8Array(await file.arrayBuffer());
  const mime = validateImageUpload(data);

  const attachmentId = crypto.randomUUID();
  await Deno.mkdir(ATTACHMENTS_DIR, { recursive: true });
  await Deno.writeFile(`${ATTACHMENTS_DIR}/${attachmentId}`, data);
  try {
    createAttachment(attachmentId, mime);
  } catch (err) {
    await Deno.remove(`${ATTACHMENTS_DIR}/${attachmentId}`).catch(() => {});
    throw err;
  }

  ctx.response.status = 201;
  ctx.response.body = { success: true, data: { id: attachmentId } };
});

router.get("/api/attachments/:attachmentId", async (ctx) => {
  const { attachmentId } = ctx.params;

  let attachment;
  try {
    attachment = getAttachment(attachmentId);
  } catch {
    ctx.response.status = 404;
    return;
  }

  await serveUploadedFile(
    ctx,
    `${ATTACHMENTS_DIR}/${attachmentId}`,
    attachment.mime,
  );
});

export default router;