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A lightweight userscript that makes finding worthwhile Prolific studies faster and less annoying.
// ==UserScript==
// @name Prolific Enhancer
// @namespace Violentmonkey Scripts
// @version 1.3
// @description A lightweight userscript that makes finding worthwhile Prolific studies faster and less annoying.
// @author Chantu
// @license MIT
// @match *://app.prolific.com/*
// @grant GM.notification
// @grant GM.getValue
// @grant GM.setValue
// ==/UserScript==
(async function () {
"use strict";
console.log("Prolific Enhancer loaded.");
const store = {
set: async (k, v) => await GM.setValue(k, JSON.stringify(v)),
get: async (k, def) =>
JSON.parse(await GM.getValue(k, JSON.stringify(def))),
};
/** @param {Function} fn @param {number} [delay=300] */
function debounce(fn, delay = 300) {
let timeoutId;
let runId = 0;
return (...args) => {
runId++;
const currentRun = runId;
clearTimeout(timeoutId);
timeoutId = setTimeout(() => {
if (currentRun !== runId) return;
Promise.resolve(fn(...args)).catch(console.error);
}, delay);
};
}
// Run on extension setup
if (!(await store.get("initialized", false))) {
await store.set("surveys", {});
await store.set("gbpToUsd", {});
// Extension setup
await store.set("initialized", true);
}
const NOTIFY_TTL_MS = 24 * 60 * 60 * 1000; // 24 hours
const GBP_TO_USD_FETCH_INTERVAL_MS = 7 * 24 * 60 * 60 * 1000; // 7 days
async function fetchGbpRate() {
const response = await fetch("https://open.er-api.com/v6/latest/GBP");
const data = await response.json();
return data.rates.USD;
}
async function checkGbpRate() {
const lastGbpToUsd = await store.get("gbpToUsd", {});
const now = Date.now();
if (
lastGbpToUsd &&
now - lastGbpToUsd.timestamp < GBP_TO_USD_FETCH_INTERVAL_MS
)
return;
const rate = (await fetchGbpRate().catch(console.error)) || 1.35; // fallback rate
await store.set("gbpToUsd", { rate, timestamp: now });
}
/** @param {HTMLElement} surveyElement */
function getSurveyFingerprint(surveyElement) {
return surveyElement.dataset.testid;
}
async function saveSurveyFingerprint(surveyElement) {
const fingerprint = getSurveyFingerprint(surveyElement);
const now = Date.now();
const entries = await store.get("surveys", {});
for (const [key, timestamp] of Object.entries(entries)) {
if (now - timestamp >= NOTIFY_TTL_MS) {
delete entries[key];
}
}
if (entries[fingerprint]) {
return false;
}
entries[fingerprint] = now;
await store.set("surveys", entries);
return true;
}
async function extractSurveys() {
const surveys = document.querySelectorAll('li[data-testid^="study-"]');
for (const survey of surveys) {
const isNewFingerprint = await saveSurveyFingerprint(survey);
if (isNewFingerprint && document.hidden) {
GM.notification({
title: survey.querySelector("h2.title").textContent,
text: survey.querySelector("span.reward").textContent,
timeout: 5000,
});
}
}
}
// Function to extract the numeric value from the string like "£8.16/hr"
/** @param {string} text */
function extractHourlyRate(text) {
const m = text.match(/[\d.]+/);
return m ? parseFloat(m[0]) : NaN;
}
// Function to map hourly rate to a color from red to green
/** @param {number} rate @param {number} [min=7] @param {number} [max=15] */
function rateToColor(rate, min = 7, max = 15) {
const clamped = Math.min(Math.max(rate, min), max);
const logMin = Math.log(min);
const logMax = Math.log(max);
const logRate = Math.log(clamped);
const ratio = (logRate - logMin) / (logMax - logMin);
const bias = Math.pow(ratio, 0.6); // Adjust bias for better color distribution
const r = Math.round(255 * (1 - bias));
const g = Math.round(255 * bias);
return `rgba(${r}, ${g}, 0, 0.63)`;
}
// Function to highlight an element based on its hourly rate
/** @param {HTMLElement} element */
function highlightElement(element) {
const rate = extractHourlyRate(element.textContent);
if (isNaN(rate)) return;
element.style.backgroundColor = rateToColor(rate);
// Set default styles
element.style.padding = "3px 4px";
element.style.borderRadius = "4px";
element.style.color = "black";
}
// Function to highlight all hourly rate elements on the page
function highlightHourlyRates() {
const elements = document.querySelectorAll(
"[data-testid='study-tag-reward-per-hour']",
);
for (const element of elements) {
// Check if the element should be ignored
if (element.getAttribute("data-testid") === "study-tag-reward") {
continue;
}
highlightElement(element);
}
}
// Function to add direct survey links
function addDirectSurveyLinks() {
const surveys = document.querySelectorAll('li[data-testid^="study-"]');
for (const survey of surveys) {
const testid = survey.getAttribute("data-testid");
const surveyId = testid.replace("study-", "");
const studyContent = survey.querySelector("div.study-content");
if (studyContent && !studyContent.querySelector(".prolific-link")) {
const container = document.createElement("div");
const link = document.createElement("a");
container.appendChild(link);
link.href = `https://app.prolific.com/studies/${surveyId}`;
link.textContent = "Take part in this study";
link.target = "_blank";
link.rel = "noopener noreferrer";
link.className = "prolific-link";
link.style.padding = "8px 24px";
link.style.borderRadius = "4px";
link.style.fontSize = "0.9em";
link.style.backgroundColor = "#0a3c95";
link.style.color = "white";
link.style.cursor = "pointer";
studyContent.appendChild(container);
container.style.padding = "0 16px 8px 16px";
}
}
}
// Function to extract currency symbol
/** @param {string} text */
function extractSymbol(text) {
const m = text.match(/[£$€]/);
return m ? m[0] : null;
}
// Function to convert all elements containing GBP to USD
async function convertToUsd() {
const elements = document.querySelectorAll("span.reward span");
const { rate } = await store.get("gbpToUsd", {});
for (const element of elements) {
const symbol = extractSymbol(element.textContent);
if (symbol !== "£") continue;
const elementRate = extractHourlyRate(element.textContent);
let modified = `$${(elementRate * rate).toFixed(2)}`;
if (element.textContent.includes("/hr")) modified += "/hr";
element.textContent = modified;
}
}
async function applyEnhancements() {
// Fetch the GBP to USD rate once a week
await checkGbpRate();
// Conversion to USD must be done first
await convertToUsd();
highlightHourlyRates();
addDirectSurveyLinks();
await extractSurveys();
}
// Apply the enhancements initially
await applyEnhancements();
const debounced = debounce(async () => {
await applyEnhancements();
}, 300);
// Observe the DOM for changes and re-run the enhancements if necessary
const observer = new MutationObserver(async (mutations) => {
const hasChanges = mutations.some(
(m) => m.addedNodes.length > 0 || m.removedNodes.length > 0,
);
if (!hasChanges) return;
debounced();
});
const config = { childList: true, subtree: true };
observer.observe(document.body, config);
})();