fill-tool.js

// ==UserScript==
// @name         Upload CSV to Website
// @namespace    jaboice.me
// @version      0.1
// @description  Upload a CSV file to fill out a form and add items to cart
// @author       JABOICE
// @match        https://test.com/
// @grant        none
// ==/UserScript==

(function() {
  'use strict';

  // Create a button for uploading the CSV
  const btn = document.createElement('input');
  btn.type = 'file';
  btn.accept = '.csv';
  btn.style.display = 'block';
  btn.addEventListener('change', handleFileUpload);
  document.body.appendChild(btn);

  function handleFileUpload(event) {
    const reader = new FileReader();
    reader.onload = processCSV;
    reader.readAsText(event.target.files[0]);
  }

  function processCSV(event) {
    const csv = event.target.result;
    const rows = csv.split('\n');

    // Loop through each row of the CSV
    for (let i = 0; i < rows.length; i++) {
      const columns = rows[i].split(',');

      // Fill out the form on the website using the columns from the CSV
      const form = document.querySelector('form');
      form.querySelector('input[name="name"]').value = columns[0];
      form.querySelector('input[name="quantity"]').value = columns[1];
      form.querySelector('input[name="price"]').value = columns[2];

      // Submit the "Add to Cart" button
      form.querySelector('input[type="submit"]').click();
    }
  }
})();