import {
  UploadPartCommand, S3Client, ListPartsCommand, CreateMultipartUploadCommand, CompleteMultipartUploadCommand, AbortMultipartUploadCommand, PutObjectCommand
} from '@aws-sdk/client-s3';
import { getSignedUrl } from '@aws-sdk/s3-request-presigner';
import { Request, Response } from 'express';

const { CLOUDFLARE_ACCOUNT_ID, CLOUDFLARE_ACCESS_KEY, CLOUDFLARE_SECRET_ACCESS_KEY, CLOUDFLARE_BUCKETNAME, CLOUDFLARE_BUCKET_URL } =
  process.env;

const R2 = new S3Client({
  region: 'auto',
  endpoint: `https://${CLOUDFLARE_ACCOUNT_ID}.r2.cloudflarestorage.com`,
  credentials: {
    accessKeyId: CLOUDFLARE_ACCESS_KEY!,
    secretAccessKey: CLOUDFLARE_SECRET_ACCESS_KEY!,
  },
});

export default async function handleR2Upload(
  endpoint: string,
  req: Request,
  res: Response
) {

  switch (endpoint) {
    case 'create-multipart-upload':
      return createMultipartUpload(req, res);
    case 'prepare-upload-parts':
      return prepareUploadParts(req, res);
    case 'complete-multipart-upload':
      return completeMultipartUpload(req, res);
    case 'list-parts':
      return listParts(req, res);
    case 'abort-multipart-upload':
      return abortMultipartUpload(req, res);
    case 'sign-part':
      return signPart(req, res);
  }
  return res.status(404).end();
}

export async function simpleUpload(data: Buffer, key: string, contentType: string) {
  const params = {
    Bucket: CLOUDFLARE_BUCKETNAME,
    Key: key,
    Body: data,
    ContentType: contentType,
  };

  const command = new PutObjectCommand({ ...params });
  await R2.send(command);

  return CLOUDFLARE_BUCKET_URL + '/' + key;
}

export async function createMultipartUpload(
  req: Request,
  res: Response
) {
  const { file, fileHash, contentType } = req.body;
  const filename = file.name;
  try {
    const params = {
      Bucket: CLOUDFLARE_BUCKETNAME,
      Key: `resources/${fileHash}/${filename}`,
      ContentType: contentType,
      Metadata: {
        'x-amz-meta-file-hash': fileHash,
      },
    };

    const command = new CreateMultipartUploadCommand({ ...params });
    const response = await R2.send(command);
    return res.status(200).json({
      uploadId: response.UploadId,
      key: response.Key,
    });
  } catch (err) {
    console.log('Error', err);
    return res.status(500).json({ source: { status: 500 } });
  }
}

export async function prepareUploadParts(
  req: Request,
  res: Response
) {
  const { partData } = req.body;

  const parts = partData.parts;

  const response = {
    presignedUrls: {},
  };

  for (const part of parts) {
    try {
      const params = {
        Bucket: CLOUDFLARE_BUCKETNAME,
        Key: partData.key,
        PartNumber: part.number,
        UploadId: partData.uploadId,
      };
      const command = new UploadPartCommand({ ...params });
      const url = await getSignedUrl(R2, command, { expiresIn: 3600 });

      // @ts-ignore
      response.presignedUrls[part.number] = url;
    } catch (err) {
      console.log('Error', err);
      return res.status(500).json(err);
    }
  }

  return res.status(200).json(response);
}

export async function listParts(req: Request, res: Response) {
  const { key, uploadId } = req.body;

  try {
    const params = {
      Bucket: CLOUDFLARE_BUCKETNAME,
      Key: key,
      UploadId: uploadId,
    };
    const command = new ListPartsCommand({ ...params });
    const response = await R2.send(command);

    return res.status(200).json(response['Parts']);
  } catch (err) {
    console.log('Error', err);
    return res.status(500).json(err);
  }
}

export async function completeMultipartUpload(
  req: Request,
  res: Response
) {
  const { key, uploadId, parts } = req.body;

  try {
    const params = {
      Bucket: CLOUDFLARE_BUCKETNAME,
      Key: key,
      UploadId: uploadId,
      MultipartUpload: { Parts: parts },
    };

    const command = new CompleteMultipartUploadCommand({
      Bucket: CLOUDFLARE_BUCKETNAME,
      Key: key,
      UploadId: uploadId,
      MultipartUpload: { Parts: parts },
    });
    const response = await R2.send(command);
    response.Location = process.env.CLOUDFLARE_BUCKET_URL + '/' + response?.Location?.split('/').at(-1);
    return response;
  } catch (err) {
    console.log('Error', err);
    return res.status(500).json(err);
  }
}

export async function abortMultipartUpload(
  req: Request,
  res: Response
) {
  const { key, uploadId } = req.body;

  try {
    const params = {
      Bucket: CLOUDFLARE_BUCKETNAME,
      Key: key,
      UploadId: uploadId,
    };
    const command = new AbortMultipartUploadCommand({ ...params });
    const response = await R2.send(command);

    return res.status(200).json(response);
  } catch (err) {
    console.log('Error', err);
    return res.status(500).json(err);
  }
}

export async function signPart(req: Request, res: Response) {
  const { key, uploadId } = req.body;
  const partNumber = parseInt(req.body.partNumber);

  const params = {
    Bucket: CLOUDFLARE_BUCKETNAME,
    Key: key,
    PartNumber: partNumber,
    UploadId: uploadId,
    Expires: 3600
  };

  const command = new UploadPartCommand({ ...params });
  const url = await getSignedUrl(R2, command, { expiresIn: 3600 });

  return res.status(200).json({
    url: url,
  });
}