Real Estate in BTC UserScript

real_estate_btc.user.js

// ==UserScript==
// @name         Real Estate Priced in BTC
// @namespace    http://tampermonkey.net/
// @version      0.2
// @updateURL    https://gist.github.com/StephenBrown2/0a01846c355ef5c56f94a1f129cc00a2
// @downloadURL  https://gist.github.com/StephenBrown2/0a01846c355ef5c56f94a1f129cc00a2
// @description  Display all home prices in BTC.
// @author       Phteven
// @match        http*://www.zillow.com/*
// @match        http*://www.redfin.com/*
// @icon         data:image/gif;base64,R0lGODlhAQABAAAAACH5BAEKAAEALAAAAAABAAEAAAICTAEAOw==
// @grant        none
// ==/UserScript==

async function getBTC() {
  const url = "https://mempool.space/api/v1/prices";
  const btc = await fetch(url).then(function (response) {
    return response.json();
  }).then(function (data) {
    return data.USD;
  }).catch(function (err) {
    console.log('Fetch Error :-S', err);
  })
  return btc;
}

async function getHistoricalBTC(date = new Date()) {
    const url = `https://mempool.space/api/v1/historical-price?currency=USD&timestamp=${Math.floor(date.getTime() / 1000)}`;
    const btc = await fetch(url).then(function (response) {
        return response.json();
    }).then(function (data) {
        return data.prices[0].USD;
    }).catch(function (err) {
        console.log('Fetch Error :-S', err);
    });
    return btc;
}

async function setRedfinLastSoldPrice() {
    let lastSold = document.querySelector('div.ListingStatusBannerSection.remodel');
    if (!lastSold) {
        console.log("Last sold element not found");
        return;
    }
    // Extract the date and price from the text "LAST SOLD ON MAR 1, 2024 FOR $384,900"
    let dateMatch = lastSold.textContent.match(/ON (.+?) FOR/);
    let priceMatch = lastSold.textContent.match(/FOR (\$[,\d]+)/);

    let date = dateMatch ? dateMatch[1] : null;
    let usdPrice = priceMatch ? priceMatch[1].replace(/[\$,]/g, '') : null;

    usdPrice = usdPrice ? parseFloat(usdPrice) : null;
    date = date ? new Date(date + " 12:00 PM") : null;

    var btcPrice = await getHistoricalBTC(date);
    if (btcPrice === 0) {
        console.error("BTC price is zero, cannot calculate BTC value.");
        return;
    }

    let BTC = (usdPrice / btcPrice).toFixed(8) + ' ₿';

    if (lastSold.hasChildNodes()) {
        for (const node of lastSold.childNodes) {
            if (node.nodeType === Node.TEXT_NODE) {
                if (node.textContent.match(/FOR \$([,\d]+)/)) {
                    let span = document.createElement('span');
                    span.title = priceMatch[1] + ' @ $' + btcPrice + '/BTC';
                    span.textContent = ' FOR ' + BTC;
                    node.replaceWith(span);
                }
            }
        }
    }
}

function getAllPrices() {
  // Combined query selector for all possible price elements
  return document.querySelectorAll(
    'div.stat-block .statsValue,' + // Redfin
    '.bp-Homecard__Price--value,' + // Redfin Homepage Cards
    '.price-text,' + // Zillow
    '[data-testid="primary-zestimate"],' + // Zestimate
    '.hs-fact-value,' + // Home Zestimate
    '[data-test="property-card-price"],' + // Zillow Cards
    '[data-testid="data-price-row"]', + // Zillow Favorite homes
    '[data-testid="price"]' // Zillow photos view
  );
}

// setBTC takes an element with a USD price, and btcPrice,
// and updates the element's innerHTML to show the BTC equivalent
// of the USD price
function setBTC(elem, btcPrice) {
  if (!elem.textContent.includes('$')) {
    return;
  }
  let usdPrice = Number(elem.textContent.replace(/[^0-9.-]+/g, ""));
  let BTC = (usdPrice / btcPrice).toFixed(8) + ' ₿';
  const inner = '<span title="' + elem.textContent + ' @ $' + btcPrice + '/BTC">' + BTC + '</span>';
  elem.innerHTML = inner;
}

(async function() {
  'use strict';

  var btcPrice = await getBTC();
  var runIt = async function() {
    var prices = getAllPrices();
    for (const priceObj of prices) {
      setBTC(priceObj, btcPrice);
    }
    await setRedfinLastSoldPrice();
  };
  window.onload = await runIt;
  setInterval(runIt, 1000);
  setInterval(async function() { btcPrice = await getBTC(); }, 60000);
})();