Extract Ledger-cli format string out of Revolut transactions page

revolut_to_ledger.js

// ==UserScript==
// @name     Revolut.com to ledger
// @version  1.2
// @grant    GM.setClipboard
// @require  https://ajax.googleapis.com/ajax/libs/jquery/3.7.1/jquery.min.js
// @require  https://gist.github.com/raw/2625891/waitForKeyElements.js
// @match    https://app.revolut.com/transactions*
// ==/UserScript==


function handleTransactionView(node) {
  let r = $('<input type="button" value="copy ledger"/>');
  let date = new Date(node.data('group'));
  console.debug('date: ' + prettyDate(date));
  node.find('div:first-child > span:first-child').first().append(r);
  r.on('click', function() {
    var result = [];
    var targets = node.find('button');
    if (targets.length == 0) {
      console.warning('WARNING: no entries found on ' + date);
    }
    targets.each(function(unused) {
      result.push(convertTransaction($(this), new Date(date)));
    });
    result.reverse();
    console.debug('retrieved ' + result.length + ' items');
    if (result.length > 0) {
      let r = result.join('\n');
	    GM.setClipboard(r);
    }
  });
}

function convertTransaction(node, date) {
  let txn = Txn.fromNode(node, date);
  if (!txn.amount) {
    return '; ignore ' + prettyDate(txn.date) + ' ' + txn.title + '\n';
  }
  let matchers = [
    [/Sold .* to .*/, convertSoldCurrency],
    [/へ売却済み*/, convertSoldCurrency],
    [/Bought .* with .*/, convertBoughtCurrency],
    [/で購入しました*/, convertBoughtCurrency],
    [/To .*/, convertSendTo],
    [/Payment from .*/, convertPaymentFrom],
    [/Money added via.*/, convertMoneyAdded],
  ];
  for (const [p, handler] of matchers) {
    let m = p.exec(txn.title);
    if (m) {
      return handler(txn, m);
    }
  }
  console.debug('regular txn');
  return convertRegularTxn(txn);
}

function convertSoldCurrency(txn, match) {
   txn.addPost(new Post('Assets:Banks:Revolut', txn.converted));
   txn.addPost(new Post('Assets:Banks:Revolut', txn.amount));
   return txn.print();
}

function convertBoughtCurrency(txn, match) {
  // Since the conversion is already covered in sold event,
  // we don't have to / must not emit the transaction.
  return [
    '; ' + prettyDate(txn.date) + ' ' + txn.title,
    '; ' + txn.amount.print() + ' ' + txn.converted.print(),
  ].join('\n') + '\n';
}

function convertSendTo(txn, match) {
  let a = txn.converted != null ? txn.converted : txn.amount;
  txn.addPost(new Post('Assets:Wire:???', a.negate()));
  txn.addPost(new Post('Assets:Banks:Revolut', txn.amount));
  return txn.print();
}

function convertPaymentFrom(txn, match) {
  txn.addPost(new Post('Assets:Banks:Revolut', txn.amount));
  txn.addPost(new Post('Assets:Wire:Revolut', txn.amount.negate()));
  return txn.print();
}

function convertMoneyAdded(txn, match) {
  txn.addPost(new Post('Assets:Banks:Revolut', txn.amount));
  txn.addPost(new Post('Assets:Wire:Revolut', txn.amount.negate()));
  return txn.print();
}

function convertRegularTxn(txn) {
  let a = txn.converted != null ? txn.converted : txn.amount;
  txn.addPost(new Post('Expenses:???', a.negate()));
  txn.addPost(new Post('Assets:Banks:Revolut', txn.amount));
  return txn.print();
}

class Txn {
  constructor(date, txnid, title, amount, converted, datetime, comment) {
    this.date=date;
    this.txnid=txnid;
    this.title=title;
    this.amount=amount;
    this.converted=converted;
    this.datetime=datetime;
    this.comment=comment;
    this.posts = new Array();
  }

  static fromNode(node, date) {
    let txnid = node.data('transactionid');
    let title = node.children('span:first-of-type').children('span:first-of-type').text();
    let time_comment = node.children('span:first-of-type').children('span:nth-of-type(2)').text();
    let tm = /(\d{1,2}):(\d{2}) ?(AM|PM)?(?: · (.*))?/.exec(time_comment);
    var datetime, comment;
    if (tm) {
      var h = parseInt(tm[1], 10);
      let m = parseInt(tm[2], 10);
      if (tm[3] == 'PM') {
        h += 12;
      }
      datetime = new Date(date);
      datetime.setHours(h, m);
      comment = tm[4];
    }
    if (!comment) {
      comment = null;
    }
    let amount = parseAmount(node.find('span:nth-of-type(2) > span:first-of-type').text());
    let converted = parseAmount(node.find('span:nth-of-type(2) > span:nth-of-type(2)').text());
    return new Txn(date, txnid, title, amount, converted, datetime, comment);
  }

  addPost(post) {
    this.posts.push(post);
  }

  print() {
    var res = [prettyDate(this.date) + ' * (' + this.txnid + ') ' + this.title];
    res.push('    ; datetime:: ' + prettyDatetime(this.datetime));
    for (const p of this.posts) {
      res.push(p.print());
    }
    return res.join('\n') + '\n';
  }
}

class Post {
  constructor(account, amount, converted=null) {
    this.account = account;
    this.amount = amount;
    this.converted = converted;
  }

  print() {
    var res = "    " + this.account + "        " + this.amount.print();
    if (this.converted != null) {
      res += " @@ " + this.converted.print();
    }
    return res;
  }
}

function prettyDate(x) {
  return x.getFullYear() + '/' + (x.getMonth()+1+'').padStart(2, '0') + '/' + (x.getDate()+'').padStart(2, '0');
}

function prettyDatetime(x) {
  return prettyDate(x) + ' ' + (''+x.getHours()).padStart(2, '0') + ':' + (''+x.getMinutes()).padStart(2, '0');
}

class Amount {
  constructor(value, commodity) {
    this.value = value;
    this.commodity = commodity;
  }

  negate() {
    let value = this.value[0] == '-' ? this.value.substr(1) : '-' + this.value;
    return new Amount(value, this.commodity);
  }

  print() {
    return this.value + ' ' + this.commodity;
  }
}

function parseAmount(x) {
  if (x == '') {
    return null;
  }
  let match = /(?:([+-]) )?([^ 0-9]+) ?([0-9,]+\.[0-9]+)/.exec(x);
  var commodity = match[2].trim();
  if (commodity == '$') {
    commodity = 'USD';
  } else if (commodity == '€') {
    commodity = 'EUR';
  } else if (commodity == '£') {
    commodity = 'GBP';
  } else if (commodity == '￥') {
    commodity = 'JPY';
  }
  var value = match[3];
  if (match[1] == '-') {
    value = '-' + value;
  }
  if (commodity == 'JPY' && value.endsWith('.00')) {
    value = value.substring(0, value.length - 3);
  }
  return new Amount(value, commodity);
}

window.addEventListener('load', init, false);

function init() {
  waitForKeyElements("[role='transactions-group']", handleTransactionView);
};