lib.js

const fs = require("fs").promises;
const path = require("path");
const process = require("process");
const { google } = require("googleapis");
const { chromium } = require("playwright");
const { Configuration, OpenAIApi } = require("openai");

require("dotenv").config();

const TOKEN_PATH = path.join(process.cwd(), "token.json");
const starterText = process.env.STARTER_TEXT;
const email = process.env.EMAIL ? process.env.EMAIL : "example@mail.com";
const password = process.env.PASSWORD ? process.env.PASSWORD : "password123";
const topicName = process.env.TOPIC_NAME
  ? process.env.TOPIC_NAME
  : "topic_name";

const configuration = new Configuration({
  apiKey: process.env.API_KEY,
});

const openai = new OpenAIApi(configuration);

async function performPlaywrightMessage(link) {
  console.log(`💃 Visiting ${link}`);
  const browser = await chromium.launch({ headless: true });
  const page = await browser.newPage();

  await page.goto(link);

  if (await page.isVisible("text='Accept all'")) {
    await page.getByRole("button", { name: "Accept all" }).click();
  }

  const listingText = await page
    .locator("div#ad_description_text")
    .allTextContents();

  const listingString = JSON.stringify(listingText);

  await page
    .locator("#rhs_column")
    .getByRole("link", { name: "Send Message" })
    .click();

  if (await page.isVisible("text='Please sign in here.'")) {
    await page.getByRole("link", { name: "Please sign in here." }).click();
    await page.locator("#login_email_username").click();
    await page.locator("#login_email_username").fill(email);
    await page.locator("#login_basic #login_password").click();
    await page.locator("#login_basic #login_password").fill(password);
    await page.getByRole("button", { name: "Login" }).click();
  }

  await page
    .getByRole("button", { name: "Yes, I have read the Security Advice" })
    .click();
  await page
    .getByPlaceholder(
      "Write your message with a personal touch and detailed information and refer to the Ad description. You can mention your availability to visit the flat and additional contact information such as your mobile phone number, where appropriate."
    )
    .click();

  console.log("🎇Generating ChatGPT reponse...");
  const gptResponse = await generateGptResponse(listingString);
  const formattedResponse = gptResponse.replace(/"/g, "");
  console.log("🎇Done!");
  await page
    .getByPlaceholder(
      "Write your message with a personal touch and detailed information and refer to the Ad description. You can mention your availability to visit the flat and additional contact information such as your mobile phone number, where appropriate."
    )
    .fill(formattedResponse);

  await page.getByRole("button", { name: "Send message" }).click();

  await browser.close();

  console.log("🍏 Message successfully sent!");
}

async function loadSavedCredentialsIfExist() {
  try {
    const content = await fs.readFile(TOKEN_PATH);
    const credentials = JSON.parse(content);
    return google.auth.fromJSON(credentials);
  } catch (err) {
    return null;
  }
}

function getLatestMessageId(entries) {
  const latestMessage = entries.reduce((acc, obj) => {
    if (obj.id > acc.id) {
      return obj;
    }
    return acc;
  });

  return latestMessage.messages[0].id;
}

function unicodeBase64Decode(text) {
  text = text.replace(/\s+/g, "").replace(/\-/g, "+").replace(/\_/g, "/");
  return decodeURIComponent(
    Array.prototype.map
      .call(atob(text), function (c) {
        return "%" + ("00" + c.charCodeAt(0).toString(16)).slice(-2);
      })
      .join("")
  );
}

function logCompleteJsonObject(jsonObject) {
  const base = jsonObject.payload.parts.filter(
    (part) => part.mimeType === "text/plain"
  )[0].body.data;

  const decodedText = unicodeBase64Decode(base);

  const regex = /https?:\/\/[^\s?]+[?&]campaign=suchauftrag_detail\b/g;
  const links = decodedText.match(regex);

  if (links && links.length >= 1) {
    links.forEach(async (link) => {
      try {
        await performPlaywrightMessage(link);
      } catch (error) {
        console.log(error);
      }
    });
  } else {
    console.log("No link found.");
  }
}

async function parseHistoryResponse(jsonObject) {
  let cred = await loadSavedCredentialsIfExist();
  const entries = jsonObject.history.filter((entry) => entry.messagesAdded);
  const messageId = getLatestMessageId(entries);
  await getMessage(cred, messageId);
}

async function resub(auth) {
  const gmail = google.gmail({ version: "v1", auth });
  const res = await gmail.users.watch({
    userId: "me",
    requestBody: {
      labelIds: ["INBOX"],
      topicName,
    },
  });
  console.log(res);
}

async function getMessage(auth, messageId) {
  const gmail = google.gmail({ version: "v1", auth });
  const res = await gmail.users.messages.get({
    userId: "me",
    id: messageId,
  });
  logCompleteJsonObject(res.data);
}

async function getHistory(auth, historyId) {
  const gmail = google.gmail({ version: "v1", auth });
  const res = await gmail.users.history.list({
    userId: "me",
    startHistoryId: historyId,
  });
  parseHistoryResponse(res.data);
}

async function tryToSendMessage() {
  let cred = await loadSavedCredentialsIfExist();
  let historyId = 19977;
  await getHistory(cred, historyId);
}

let generateGptResponse = async (listingText) => {
  const prompt = `
    Can you spice up the following text: "${starterText}" The updated text should explain why I would fit in the flatshare with the following listing text: "${listingText}". Add some emojies as well. Mention that my semester is from September to March, so a stay for that perioud would be ideal (but Im always flexible)! And if the listing is written in German, the answer should be in German as well. And if the listing says I need to say a specific word, start the whole text with that word!
  `;

  const turboMessage = [
    { role: "system", content: `I am applying to a flatshare listing.` },
    { role: "user", content: prompt },
  ];

  const response = await openai.createChatCompletion({
    model: "gpt-3.5-turbo",
    messages: turboMessage,
    max_tokens: 1000,
    temperature: 0.2,
  });

  return response.data.choices[0].message.content;
};

(async () => {
  let cred = await loadSavedCredentialsIfExist();
  await resub(cred);
})();

module.exports = { tryToSendMessage };