async function scrollDown() {
  const wrapper = document.querySelector("#search-page-list-container");
  await new Promise((resolve, reject) => {
    var totalHeight = 0;
    var distance = 600;

    var timer = setInterval(async () => {
      var scrollHeightBefore = wrapper.scrollHeight;
      wrapper.scrollBy(0, distance);
      totalHeight += distance;

      if (totalHeight >= scrollHeightBefore) {
        totalHeight = 0;

        // Calculate scrollHeight after waiting
        var scrollHeightAfter = wrapper.scrollHeight;

        if (scrollHeightAfter > scrollHeightBefore) {
          // More content loaded, keep scrolling
          return;
        } else {
          // No more content loaded, stop scrolling
          clearInterval(timer);
          resolve();
        }
      }
    }, 400);
  });
}

function getListings() {
  const listings = [];

  const lis = document.querySelectorAll("#search-page-list-container ul li");
  for (let i = 0; i < lis.length; i++) {
    const listing = lis[i];
    // if listing contains class ListItem, then it's a listing
    const classes = Array.from(listing.classList).join(" ");
    if (classes.includes("ListItem")) {
      // get the script tag
      const script = listing.querySelector("script");
      if (!script) {
        continue;
      }

      // find the ul who has a class that includes StyledPropertyCardHomeDetailsList
      const beds = listing
        ?.querySelector(
          'ul[class*="StyledPropertyCardHomeDetailsList"] li:nth-child(1)'
        )
        ?.textContent?.match(/\d+/)?.[0];
      const baths = listing
        ?.querySelector(
          'ul[class*="StyledPropertyCardHomeDetailsList"] li:nth-child(2)'
        )
        ?.textContent?.match(/\d+/)?.[0];

      // get the span with data-test=property-card-price
      const priceString = listing.querySelector(
        'span[data-test="property-card-price"]'
      )?.textContent;

      const price = Number(priceString.replace(/[^0-9.-]+/g, ""));

      const json = JSON.parse(script.textContent);
      listings.push({
        ...json.address,
        ...json.floorSize,
        ...json.geo,
        priceString: priceString,
        price,
        beds: beds ? Number(beds) : "",
        baths: baths ? Number(baths) : "",
        sqft: json?.floorSize?.value
          ? Number(json?.floorSize?.value.replace(/[^0-9.-]+/g, ""))
          : "",
        name: json.name,
        url: json.url,
      });
    }
  }
  return listings;
}

function createCSV(jsonData, fileName) {
  // Convert JSON to CSV
  const csvData = [];

  // Extract the headers
  const headers = Object.keys(jsonData[0]);
  csvData.push(headers.join(","));

  jsonData.forEach((item) => {
    const row = [];
    for (const key in item) {
      if (item.hasOwnProperty(key)) {
        if (typeof item[key] === "number") {
          row.push(item[key]);
          continue;
        }
        const value = item[key]?.includes(",") ? `"${item[key]}"` : item[key];
        row.push(value);
      }
    }
    csvData.push(row.join(","));
  });

  // Create a Blob containing the CSV data
  const csvBlob = new Blob([csvData.join("\n")], {
    type: "text/csv;charset=utf-8",
  });

  // Create a URL for the Blob
  const csvUrl = URL.createObjectURL(csvBlob);

  // Create a link element
  const link = document.createElement("a");
  link.href = csvUrl;
  link.target = "_blank";
  link.download = fileName;

  // Append the link to the body
  document.body.appendChild(link);

  // Trigger a click event on the link
  link.click();

  // Remove the link and revoke the Blob URL
  document.body.removeChild(link);
  URL.revokeObjectURL(csvUrl);
}

async function scrapeZillow() {
  let page = 1;
  const allListings = [];

  await scrollDown();
  const listings = getListings();
  console.log("listings", listings);
  allListings.push(...listings);

  // a title=Next page
  let nextButton = document.querySelector('a[title="Next page"]');

  // check aria-disabled
  let disabled = nextButton?.getAttribute("aria-disabled");

  if (nextButton && disabled !== "true") {
    nextButton.click();
  }

  while (nextButton && disabled !== "true") {
    console.log("page", page);
    await scrollDown();
    const listings = getListings();
    console.log(`You scraped ${listings.length} listings!`);
    console.log(
      `Check out my course for all my web scraping secrets: https://adrianhorning.gumroad.com/l/the-ultimate-web-scraping-course`
    );
    allListings.push(...listings);
    nextButton = document.querySelector('a[title="Next page"]');
    disabled = nextButton.getAttribute("aria-disabled");
    if (disabled === "true") {
      break;
    }
    nextButton.click();
    page++;
  }

  console.log(`Congrats! 🎉 You scraped ${allListings.length} listings!`);
  
  console.log('Check out my web scraping course: https://adrianhorning.gumroad.com/l/the-ultimate-web-scraping-course')

  createCSV(allListings, `zillowListings-${new Date().getTime()}.csv`);
}
await scrapeZillow();