scripts/JS/Open Magnets in Transmission.user.js

// ==UserScript==
// @name        Open Magnets in Transmission
// @namespace   ca.tarka.home
// @description Open magnet links from ThePirateBay in the Transmission web client
// @include     https://thepiratebay.org/*
// @include     https://www.thepiratebay.org/*
// @include     https://thepiratebay.se/*
// @include     https://www.thepiratebay.se/*
// @include     https://1337x.to/*
// @include     https://tpb.party/*
// @include     https://thepiratebay.net/*
// @include     https://downloadtorrentfile.com/*
// @include     https://rarbg2020.org/*
// @include     https://torrentz2eu.org/*
// @include     http://storm:9091/*
// @include     storm.tarka:9091/*
// @include     https://bittorrent/*
// @include     https://bittorrent.tarka/*
// @connect     storm.tarka
// @connect     storm.tarka:9091
// @connect     bittorrent
// @connect     bittorrent.tarka
// @version     1.1
// @grant       GM_xmlhttpRequest
// @grant       GM_setValue
// @grant       GM_getValue
// ==/UserScript==

const options = {
  host: 'bittorrent',
  altHosts: ['bt', 'bittorrent.tarka', 'bt.tarka', 'storm:9091', 'storm.tarka:9091', 'bittorrent'],
  auth: 'YnQ6bm9QYXNzd29yZDEyMw==',
  destination: '/var/lib/transmission-daemon/downloads/unsorted'
};
const csrfTokenkey = 'csrfToken';

(function() {
  let host = document.location.host;
  if( host == options.host || options.altHosts.includes(host) ) {
    getCsrfToken();
    //setConfig();
  } else if( self == top ) {
    setTimeout( setupLinks, 300 );
  }
})();

function getCsrfToken() {
  console.log( 'Attempting to get CSRF token' );
  if( !unsafeWindow.transmission ) {
    console.log( 'Transmission doesn\'t exist on window. Trying again.' );
    return setTimeout( getCsrfToken, 100 );
  }
  let token = unsafeWindow.transmission.remote._token;
  console.log( 'Storing CSRF token:', token );
  GM_setValue( csrfTokenkey, token );
}

function setConfig() {
  console.log( 'Attempting to set seeding config' );
  const data = {
    method: "session-set",
	arguments: {
		"seedRatioLimited": true,
		"seedRatioLimit": 0.001,
		"idle-seeding-limit-enabled": true,
		"idle-seeding-limit": 1,
		"speed-limit-up-enabled": true,
		"speed-limit-up": 5
	}
  };

  postData( data, () => console.log( 'Updated configs' ), false );
}

var searches = 0;
function setupLinks() {
  console.log( 'setting up links' );
  let links = Array.from( document.querySelectorAll( 'a[href^="magnet:"]' ) );
  if( ++searches >= 10 ) {
    console.error( 'Too many searches. Aborting.' );
    return;
  }

  if( !links.length ) {
    console.log( 'No links found on page. Trying again in a moment.', links );
    return setTimeout( setupLinks, 50 );
  } else {
    console.log( 'Got links', links );
    links.forEach( x => x.addEventListener( 'click', clickLink ) );
  }
}

function clickLink( event ) {
  console.log( 'Clicking link', event );
  let magnet = this.href;
  startTorrent( magnet );

  // Stop the link from being clicked
  event.preventDefault();
}

function startTorrent( magnet ) {
  let data = {
    method: 'torrent-add',
    arguments: {
      paused: false,
      'download-dir': options.destination,
      filename: magnet
    }
  };
  postData(
    data,
    () => alert( 'Successfully added torrent' ),
    true
  );
}

function postData( data, success, showError ) {
  GM_xmlhttpRequest( {
    method: 'POST',
    url: `https://${options.host}/transmission/rpc`,
    data: JSON.stringify( data ),
    headers: {
      'Authorization': `Basic ${options.auth}`,
      'X-Transmission-Session-Id': GM_getValue( csrfTokenkey )
    },
    onload: response => {
      if( response.status != 200 ) {
        return onError( response );
      }
      success();
    },
    onerror: response => {
      console.error( response );
      if( showError ) {
        alert( 'An error occurred adding the torrent' );
      }
    }
  } );

  function onError( response ) {
    console.error( response );
    if( !showError ) {
      return;
    }
    if( response.statusText == 'Conflist' ) {
        alert('Received "Conflict" error.\n\nHas this torrent already been added?');
    } else if( response.status == 409 ) {
      alert( 'CSRF token is out of date.\n\nPlease open the Transmission UI in another tab, then try again' );
    } else {
      alert( 'Unknown error occurred adding the event. More details available in the browser console.' );
    }
  }
}