automa/src/content/index.js

import browser from 'webextension-polyfill';
import { nanoid } from 'nanoid';
import { toCamelCase } from '@/utils/helper';
import executedBlock from './executed-block';
import blocksHandler from './blocks-handler';

(() => {
  if (window.isAutomaInjected) return;

  window.isAutomaInjected = true;

  browser.runtime.onMessage.addListener((data) => {
    return new Promise((resolve, reject) => {
      if (data.isBlock) {
        const removeExecutedBlock = executedBlock(
          data,
          data.executedBlockOnWeb
        );

        const handler = blocksHandler[toCamelCase(data.name)];

        if (handler) {
          handler(data)
            .then((result) => {
              removeExecutedBlock();
              resolve(result);
            })
            .catch(reject);

          return;
        }
        console.error(`"${data.name}" doesn't have a handler`);

        resolve('');
        return;
      }

      switch (data.type) {
        case 'content-script-exists':
          resolve(true);
          break;
        case 'give-me-the-frame-id':
          browser.runtime.sendMessage({
            type: 'this-is-the-frame-id',
          });
          resolve();
          break;
        case 'loop-elements': {
          const selectors = [];
          const attrId = nanoid(5);
          const elements = document.body.querySelectorAll(data.selector);

          elements.forEach((el, index) => {
            if (data.max > 0 && selectors.length - 1 > data.max) return;

            const attrName = 'automa-loop';
            const attrValue = `${attrId}--${index}`;

            el.setAttribute(attrName, attrValue);
            selectors.push(`[${attrName}="${attrValue}"]`);
          });

          resolve(selectors);
          break;
        }
        default:
      }
    });
  });
})();