import React, { useContext, useCallback } from "react"
import DialogContext from "./dialogContext"
import * as util from "../util"

export default HelpButton = ->
  openDialog = useContext DialogContext

  showHelp = ->
    openDialog do ->
      <React.Fragment>
        <p><strong>Angry.Im Pastebin Service</strong><br/>
           Source code:&nbsp;
          <a target="_blank" href="https://cgit.typeblog.net/worker-pastebin">
            https://cgit.typeblog.net/worker-pastebin
          </a>
        </p>
        <p>
          This application is intended as a programming practice.
          There is <strong>absolutely no guarantee</strong> on its functionality, security and reliability.
        </p>
        <p>
          <strong>Maximum file size: {util.humanFileSize util.MAX_UPLOAD_SIZE}</strong>, all uploads are kept for <strong>{util.FILE_LIFETIME}</strong> only.
        </p>
        <p>
          File uploads with <strong>"Encryption: ON"</strong> are encrypted with <i>AES-128-GCM</i> before uploading to server.
          The encryption key and IV (<i>Initialization Vector</i>) are generated <strong>in your browser</strong> and not uploaded to server.<br/>
          They are appended to the final uploaded URL in the form of {"\"#<key>-<iv>\""} (as a <a target="_blank" href="https://en.wikipedia.org/wiki/Fragment_identifier"><i>Fragment Identifier</i></a>),&nbsp;
          so that they will <strong>not</strong> be sent to the server as part of the URL when you access the file later from your browser.
        </p>
        <p>
          The decryption will also be done entirely in your browser. Therefore, it is not supported to access encrypted files outside of a modern browser.&nbsp;
          If you plan to download the shared file from outside the browser (e.g. command line) or on a low-performance device, use <strong>"Encryption: OFF"</strong>.
        </p>
        <p>
          Please <strong>refrain from uploading illegal content and / or abusing the service</strong>. This service is provided by the maintainer for convenience,&nbsp;
          but failure to keep reasonable usage of the service may result in your content being removed before the {util.FILE_LIFETIME.replace " ", "-"} mark and your IP being blocked from accessing this service.&nbsp;
          The service maintainer <strong>reserves sole authority</strong> on deciding whether a piece of content is considered abusive or not.
        </p>
      </React.Fragment>
  showHelp = useCallback showHelp, [openDialog]

  <button
    className="button-blue"
    onClick={showHelp}
  >
    Help
  </button>