// pages/api/upload.js

import mime from "mime";
import { join } from "path";
import { stat, mkdir, writeFile } from "fs/promises";
import * as dateFn from "date-fns";
import response from "@/lib/res";


export async function POST(req) {
  const formData = await req.formData();
  const file = formData.get("file");
  if (!file) {
    return response({ msg: "请选择文件上传" }, "err");
  }

  const buffer = Buffer.from(await file.arrayBuffer());
  const relativeUploadDir = `/uploads/${dateFn.format(
    Date.now(),
    "yyyy-MM-dd"
  )}`;
  const uploadDir = join(process.cwd(), "public", relativeUploadDir);

  //找文件夹 未找到->创建
  try {
    await stat(uploadDir);
  } catch (e) {
    if (e.code === "ENOENT") {
      await mkdir(uploadDir, { recursive: true });
    } else {
      return response({ msg: "当上传文件时创建文件夹失败" }, "err");
    }
  }

  //写入文件到指定日期到文件夹
  try {
    const uniqueSuffix = `${Date.now()}-${Math.round(Math.random() * 1e9)}`;
    const filename = `${file.name.replace(
      /\.[^/.]+$/,
      ""
    )}-${uniqueSuffix}.${mime.getExtension(file.type)}`;

    await writeFile(`${uploadDir}/${filename}`, buffer);
    return response(
      { fileUrl: `${relativeUploadDir}/${filename}`, fileName: file.name },
      "上传成功"
    );
  } catch (e) {
    return response({ msg: "文件上传失败" }, "err");
  }
}