// from: https://github.com/remix-run/examples/blob/main/file-and-s3-upload/app/utils/s3.server.ts

import { PassThrough } from "stream";

import AWS from "aws-sdk";
import type { UploadHandler } from "@remix-run/node";
import { writeAsyncIterableToWritable } from "@remix-run/node";
import { nanoid } from "nanoid";
import invariant from "tiny-invariant";

const envVars = () => {
  const {
    STORAGE_END_POINT,
    STORAGE_ACCESS_KEY,
    STORAGE_SECRET,
    STORAGE_REGION,
    STORAGE_BUCKET,
  } = process.env;

  if (
    !(
      STORAGE_ACCESS_KEY &&
      STORAGE_END_POINT &&
      STORAGE_SECRET &&
      STORAGE_REGION &&
      STORAGE_BUCKET
    )
  ) {
    throw new Error(`Storage is missing required configuration.`);
  }

  return {
    STORAGE_END_POINT,
    STORAGE_ACCESS_KEY,
    STORAGE_SECRET,
    STORAGE_REGION,
    STORAGE_BUCKET,
  };
};

const uploadStream = ({ Key }: Pick<AWS.S3.Types.PutObjectRequest, "Key">) => {
  const {
    STORAGE_END_POINT,
    STORAGE_ACCESS_KEY,
    STORAGE_SECRET,
    STORAGE_REGION,
    STORAGE_BUCKET,
  } = envVars();

  const s3 = new AWS.S3({
    endpoint: STORAGE_END_POINT,
    s3ForcePathStyle: false,
    credentials: {
      accessKeyId: STORAGE_ACCESS_KEY,
      secretAccessKey: STORAGE_SECRET,
    },
    region: STORAGE_REGION,
  });
  const pass = new PassThrough();
  return {
    writeStream: pass,
    promise: s3
      .upload({ Bucket: STORAGE_BUCKET, Key, Body: pass, ACL: "public-read" })
      .promise(),
  };
};

export async function uploadStreamToS3(data: any, filename: string) {
  const stream = uploadStream({
    Key: filename,
  });
  await writeAsyncIterableToWritable(data, stream.writeStream);
  const file = await stream.promise;
  return file.Location;
}

export const s3UploadHandler: UploadHandler = async ({
  name,
  filename,
  data,
}) => {
  if (name !== "img") {
    return undefined;
  }

  const [, ending] = filename!.split(".");
  invariant(ending);
  const newFilename = `${nanoid()}-${Date.now()}.${ending}`;

  const uploadedFileLocation = await uploadStreamToS3(data, newFilename);
  return uploadedFileLocation;
};