utils.ts

import { FILEBASE_API_URL } from './constants.ts'
import { aws4, AwsCredentialIdentity, Buffer, IHttpRequest, QueryParameterBag } from './deps.ts'
import { RequiredArgs } from './types.ts'

export const parseUrl = (
  url: string | URL,
): Pick<IHttpRequest, 'hostname' | 'port' | 'protocol' | 'path' | 'query'> => {
  if (typeof url === 'string') {
    return parseUrl(new URL(url))
  }
  const { hostname, pathname, port, protocol } = url as URL

  return {
    hostname,
    port: port ? parseInt(port) : undefined,
    protocol,
    path: pathname,
    query: undefined,
  }
}

export const generateFilebaseRequestOptions = (
  token: string,
  requestOptions: aws4.Request & { key?: string },
) => {
  const [accessKeyId, secretAccessKey] = atob(token).split(':')
  if (!accessKeyId || !secretAccessKey) {
    throw new Error('Missing access key ID and secret access key')
  }
  aws4.sign(requestOptions, { accessKeyId, secretAccessKey })
  return requestOptions
}

const te = new TextEncoder()

export const toUint8Array = (
  data: string | ArrayBuffer | ArrayBufferView,
): Uint8Array => {
  if (typeof data === 'string') {
    return te.encode(data)
  }

  if (ArrayBuffer.isView(data)) {
    return new Uint8Array(
      data.buffer,
      data.byteOffset,
      data.byteLength / Uint8Array.BYTES_PER_ELEMENT,
    )
  }

  return new Uint8Array(data)
}
const hexEncode = (c: string) => `%${c.charCodeAt(0).toString(16).toUpperCase()}`

const escapeUri = (uri: string): string =>
  // AWS percent-encodes some extra non-standard characters in a URI
  encodeURIComponent(uri).replace(/[!'()*]/g, hexEncode)

export const buildQueryString = (query: QueryParameterBag): string => {
  const parts: string[] = []
  for (let key of Object.keys(query).sort()) {
    const value = query[key]
    key = escapeUri(key)
    if (Array.isArray(value)) {
      for (let i = 0, iLen = value.length; i < iLen; i++) {
        parts.push(`${key}=${escapeUri(value[i])}`)
      }
    } else {
      let qsEntry = key
      if (value || typeof value === 'string') {
        qsEntry += `=${escapeUri(value)}`
      }
      parts.push(qsEntry)
    }
  }

  return parts.join('&')
}

export const castSourceData = (
  toCast: string | Buffer | ArrayBuffer,
  encoding?: BufferEncoding,
): Buffer => {
  if (Buffer.isBuffer(toCast)) {
    return toCast
  }

  if (typeof toCast === 'string') {
    return Buffer.from(toCast, encoding)
  }

  if (ArrayBuffer.isView(toCast)) {
    return Buffer.from(toCast.buffer, toCast.byteOffset, toCast.byteLength)
  }

  return Buffer.from(toCast)
}

export const formatUrl = (
  request: Omit<IHttpRequest, 'headers' | 'method'>,
): string => {
  const { port, query } = request
  let { protocol, path, hostname } = request
  if (protocol && protocol.slice(-1) !== ':') {
    protocol += ':'
  }
  if (port) {
    hostname += `:${port}`
  }
  if (path && path.charAt(0) !== '/') {
    path = `/${path}`
  }
  let queryString = query ? buildQueryString(query) : ''
  if (queryString && queryString[0] !== '?') {
    queryString = `?${queryString}`
  }
  let auth = ''
  if (request.username != null || request.password != null) {
    const username = request.username ?? ''
    const password = request.password ?? ''
    auth = `${username}:${password}@`
  }
  let fragment = ''
  if (request.fragment) {
    fragment = `#${request.fragment}`
  }
  return `${protocol}//${auth}${hostname}${path}${queryString}${fragment}`
}

export const fromEnv = (filebaseToken: string): () => Promise<AwsCredentialIdentity> => {
  return async () => {
    const [accessKeyId, secretAccessKey] = atob(filebaseToken).split(':')
    if (!accessKeyId || !secretAccessKey) {
      throw new Error('Missing access key ID and secret access key')
    }
    return {
      accessKeyId,
      secretAccessKey,
    }
  }
}

export const createBucket = async (
  { bucketName, apiUrl, token }: RequiredArgs,
) => {
  let requestOptions: aws4.Request = {
    host: `${bucketName}.${apiUrl ?? FILEBASE_API_URL}`,
    region: 'us-east-1',
    method: 'PUT',
    service: 's3',
    headers: {
      'Content-Length': 0,
    },
  }
  requestOptions = generateFilebaseRequestOptions(token, requestOptions)
  return await fetch(`https://${requestOptions.host}/`, requestOptions as RequestInit)
    .then((res) => res.status == 200)
}