Show USD price next to ETH amounts on death.fun
// ==UserScript==
// @name death.fun ETH → USD overlay
// @namespace http://tampermonkey.net/
// @version 0.1.0
// @description Show USD price next to ETH amounts on death.fun
// @author Koi
// @match https://death.fun/
// @run-at document-idle
// @grant none
// @license MIT
// ==/UserScript==
(function () {
'use strict';
const ETH_REGEX = /([-+]?[\d.,]+)\s*ETH\b/i;
const NUMERIC_REGEX = /^[-+]?[\d.,]+$/;
const MAX_TEXT_LENGTH = 90;
const conversions = new WeakMap();
const inputDisplays = new WeakMap();
const trackedInputs = new Set();
const usdFormatterLarge = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
minimumFractionDigits: 2,
maximumFractionDigits: 2,
});
const usdFormatterSmall = new Intl.NumberFormat('en-US', {
style: 'currency',
currency: 'USD',
minimumFractionDigits: 4,
maximumFractionDigits: 4,
});
let ethPriceUsd = null;
function formatUsd(value, forcePlus) {
const abs = Math.abs(value);
const formatter = abs < 1 ? usdFormatterSmall : usdFormatterLarge;
let formatted = formatter.format(abs);
if (value < 0) {
formatted = '-' + formatted;
} else if (forcePlus) {
formatted = '+' + formatted;
}
return formatted;
}
function updateSpan(span) {
const ethAmount = parseFloat(span.dataset.ethAmount);
if (!Number.isFinite(ethAmount)) {
return;
}
const sign = span.dataset.ethSign || '';
if (ethPriceUsd == null) {
span.textContent = ' (USD …)';
span.title = 'USD conversion in progress…';
return;
}
const usdValue = ethAmount * ethPriceUsd;
const formatted = formatUsd(usdValue, sign === '+' && usdValue >= 0);
span.textContent = ' (' + formatted + ' USD)';
span.title = 'Based on 1 ETH = ' + formatUsd(ethPriceUsd, false) + ' USD';
}
function deriveSign(matchText, parent, node) {
const trimmed = matchText.trim();
if (trimmed.startsWith('+')) {
return '+';
}
if (trimmed.startsWith('-')) {
return '-';
}
const parentText = (parent?.textContent || '').trim();
const parentMatch = parentText.match(ETH_REGEX);
if (parentMatch) {
const parentTrimmed = parentMatch[1].trim();
if (parentTrimmed.startsWith('+')) {
return '+';
}
if (parentTrimmed.startsWith('-')) {
return '-';
}
}
const prev = node.previousSibling;
if (prev && prev.nodeType === Node.TEXT_NODE) {
const prevTrim = prev.textContent?.trim();
if (prevTrim === '+') {
return '+';
}
if (prevTrim === '-') {
return '-';
}
}
return '';
}
function elementHasEthIcon(element) {
if (!element || element.nodeType !== Node.ELEMENT_NODE) {
return false;
}
return element.querySelector?.('svg[viewBox="0 0 9 15"]') != null;
}
function processTextNode(node) {
if (node.nodeType !== Node.TEXT_NODE) {
return;
}
const parent = node.parentNode;
if (!parent) {
return;
}
if (parent instanceof HTMLElement && parent.classList.contains('deathusd-conversion')) {
return;
}
const parentTag = parent.nodeName;
if (parentTag === 'SCRIPT' || parentTag === 'STYLE' || parentTag === 'NOSCRIPT') {
return;
}
const text = node.textContent || '';
const trimmed = text.trim();
if (!trimmed || trimmed.length > MAX_TEXT_LENGTH) {
return;
}
function isLikelyEthContext() {
const elementParent = node.parentElement;
if (elementHasEthIcon(elementParent)) {
return true;
}
const grandParent = elementParent?.parentElement;
if (elementHasEthIcon(grandParent)) {
return true;
}
const labels = [elementParent, grandParent]
.map(el => (el?.getAttribute?.('aria-label') || el?.getAttribute?.('title') || '')?.toLowerCase?.())
.filter(Boolean);
if (labels.some(label => label.includes('eth'))) {
return true;
}
return false;
}
let match = text.match(ETH_REGEX);
let numberPart;
let sign;
let ethAmount;
if (match) {
numberPart = match[1].replace(/,/g, '');
ethAmount = parseFloat(numberPart);
if (!Number.isFinite(ethAmount)) {
return;
}
sign = deriveSign(match[1], parent, node);
} else if (NUMERIC_REGEX.test(trimmed) && isLikelyEthContext()) {
numberPart = trimmed.replace(/,/g, '');
ethAmount = parseFloat(numberPart);
if (!Number.isFinite(ethAmount)) {
return;
}
sign = deriveSign(trimmed, parent, node);
} else {
return;
}
if (sign === '-' && ethAmount > 0) {
ethAmount = -ethAmount;
}
let span = conversions.get(node);
if (!span || !span.isConnected || span.parentNode !== parent) {
span = document.createElement('span');
span.className = 'deathusd-conversion';
span.style.marginLeft = '0.35em';
span.style.fontSize = '0.85em';
span.style.opacity = '0.75';
parent.insertBefore(span, node.nextSibling);
conversions.set(node, span);
}
span.dataset.ethAmount = String(ethAmount);
span.dataset.ethSign = sign;
updateSpan(span);
}
function isLikelyEthInput(input) {
if (!(input instanceof HTMLInputElement)) {
return false;
}
const type = (input.getAttribute('type') || 'text').toLowerCase();
if (!['', 'text', 'number'].includes(type)) {
return false;
}
const numericMode = input.getAttribute('inputmode');
if (numericMode && !['decimal', 'numeric'].includes(numericMode)) {
return false;
}
if (input.dataset.deathusdInput === 'yes') {
return true;
}
const attrHints = [input.getAttribute('aria-label'), input.getAttribute('placeholder'), input.name]
.filter(Boolean)
.map(value => value.toLowerCase());
if (attrHints.some(value => value.includes('usd'))) {
return false;
}
if (attrHints.some(value => value.includes('eth'))) {
input.dataset.deathusdInput = 'yes';
return true;
}
const containers = [input.parentElement, input.parentElement?.parentElement, input.parentElement?.parentElement?.parentElement, input.closest('[role="group"]')];
for (const container of containers) {
if (!container) {
continue;
}
if (elementHasEthIcon(container)) {
input.dataset.deathusdInput = 'yes';
return true;
}
const text = container.textContent || '';
if (/\b(eth|bet)\b/i.test(text)) {
input.dataset.deathusdInput = 'yes';
return true;
}
}
let ancestor = input.parentElement;
for (let depth = 0; ancestor && depth < 5; depth += 1) {
if (elementHasEthIcon(ancestor)) {
input.dataset.deathusdInput = 'yes';
return true;
}
const text = ancestor.textContent || '';
if (/\beth\b/i.test(text)) {
input.dataset.deathusdInput = 'yes';
return true;
}
ancestor = ancestor.parentElement;
}
return false;
}
function updateInputDisplay(input) {
const span = inputDisplays.get(input);
if (!span) {
return;
}
const rawValue = (input.value || '').trim();
if (!rawValue) {
span.textContent = '';
span.style.display = 'none';
return;
}
const normalized = rawValue.replace(/\s+/g, '').replace(/,/g, '');
const amount = parseFloat(normalized);
if (!Number.isFinite(amount)) {
span.textContent = '';
span.style.display = 'none';
return;
}
span.style.display = 'block';
if (ethPriceUsd == null) {
span.textContent = '≈ USD …';
span.title = 'USD conversion in progress…';
return;
}
const usdValue = amount * ethPriceUsd;
span.textContent = '≈ ' + formatUsd(usdValue, false) + ' USD';
span.title = 'Based on 1 ETH = ' + formatUsd(ethPriceUsd, false) + ' USD';
}
function ensureInputAugmented(input) {
if (!isLikelyEthInput(input)) {
return;
}
let span = inputDisplays.get(input);
if (!span || !span.isConnected) {
span = document.createElement('div');
span.className = 'deathusd-input';
span.style.marginTop = '0.35em';
span.style.fontSize = '0.85em';
span.style.opacity = '0.75';
span.style.textAlign = 'right';
span.style.fontFamily = 'inherit';
span.style.display = 'none';
input.insertAdjacentElement('afterend', span);
inputDisplays.set(input, span);
trackedInputs.add(input);
const handler = () => updateInputDisplay(input);
input.addEventListener('input', handler);
input.addEventListener('change', handler);
}
updateInputDisplay(input);
}
function processElement(element) {
if (element instanceof HTMLInputElement) {
ensureInputAugmented(element);
}
}
function scanNode(node) {
if (node.nodeType === Node.TEXT_NODE) {
processTextNode(node);
} else if (node.nodeType === Node.ELEMENT_NODE) {
processElement(node);
node.childNodes.forEach(scanNode);
}
}
function refreshAllSpans() {
document.querySelectorAll('.deathusd-conversion').forEach(updateSpan);
}
function refreshAllInputs() {
for (const input of trackedInputs) {
if (!document.contains(input)) {
trackedInputs.delete(input);
continue;
}
ensureInputAugmented(input);
}
}
async function fetchPrice() {
try {
const response = await fetch('https://min-api.cryptocompare.com/data/price?fsym=ETH&tsyms=USD', {
cache: 'no-cache',
headers: { Accept: 'application/json' },
});
if (!response.ok) {
throw new Error('HTTP ' + response.status);
}
const data = await response.json();
const price = Number(data?.USD);
if (Number.isFinite(price) && price > 0) {
ethPriceUsd = price;
refreshAllSpans();
refreshAllInputs();
}
} catch (error) {
console.warn('[deathusd] Unable to fetch ETH price', error);
}
}
function init() {
if (!document.body) {
return;
}
scanNode(document.body);
const observer = new MutationObserver(mutations => {
for (const mutation of mutations) {
if (mutation.type === 'childList') {
mutation.addedNodes.forEach(scanNode);
} else if (mutation.type === 'characterData') {
scanNode(mutation.target);
} else if (mutation.type === 'attributes' && mutation.target instanceof HTMLInputElement) {
ensureInputAugmented(mutation.target);
updateInputDisplay(mutation.target);
}
}
});
observer.observe(document.body, {
childList: true,
subtree: true,
characterData: true,
attributes: true,
attributeFilter: ['value'],
});
fetchPrice();
setInterval(fetchPrice, 60000);
}
if (document.readyState === 'loading') {
document.addEventListener('DOMContentLoaded', init, { once: true });
} else {
init();
}
})();