parkrun p-index display

The parkrun p-index is an unofficial statistic that measures the number of different parkrun events a person has completed a specific number of times. To achieve a p-index of 10, you must have completed at least 10 different parkrun events 10 times each. This script calculate the p-index for a parkrunner and displays it on their results page.

As of 2025-11-03. See the latest version.

You will need to install an extension such as Tampermonkey, Greasemonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Violentmonkey to install this script.

You will need to install an extension such as Tampermonkey or Userscripts to install this script.

You will need to install an extension such as Tampermonkey to install this script.

You will need to install a user script manager extension to install this script.

(I already have a user script manager, let me install it!)

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install an extension such as Stylus to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

You will need to install a user style manager extension to install this style.

(I already have a user style manager, let me install it!)

// ==UserScript==
// @name         parkrun p-index display
// @description  The parkrun p-index is an unofficial statistic that measures the number of different parkrun events a person has completed a specific number of times. To achieve a p-index of 10, you must have completed at least 10 different parkrun events 10 times each. This script calculate the p-index for a parkrunner and displays it on their results page.
// @author       Pete Johns (@johnsyweb)
// @grant        none
// @homepage     https://johnsy.com/tampermonkey-parkrun/
// @icon         https://www.google.com/s2/favicons?sz=64&domain=parkrun.com.au
// @license      MIT
// @match        *://www.parkrun.ca/parkrunner/*/all/
// @match        *://www.parkrun.co.at/parkrunner/*/all/
// @match        *://www.parkrun.co.nl/parkrunner/*/all/
// @match        *://www.parkrun.co.nz/parkrunner/*/all/
// @match        *://www.parkrun.co.za/parkrunner/*/all/
// @match        *://www.parkrun.com.au/parkrunner/*/all/
// @match        *://www.parkrun.com.de/parkrunner/*/all/
// @match        *://www.parkrun.dk/parkrunner/*/all/
// @match        *://www.parkrun.fi/parkrunner/*/all/
// @match        *://www.parkrun.fr/parkrunner/*/all/
// @match        *://www.parkrun.ie/parkrunner/*/all/
// @match        *://www.parkrun.it/parkrunner/*/all/
// @match        *://www.parkrun.jp/parkrunner/*/all/
// @match        *://www.parkrun.lt/parkrunner/*/all/
// @match        *://www.parkrun.my/parkrunner/*/all/
// @match        *://www.parkrun.no/parkrunner/*/all/
// @match        *://www.parkrun.org.uk/parkrunner/*/all/
// @match        *://www.parkrun.pl/parkrunner/*/all/
// @match        *://www.parkrun.se/parkrunner/*/all/
// @match        *://www.parkrun.sg/parkrunner/*/all/
// @match        *://www.parkrun.us/parkrunner/*/all/
// @namespace    http://tampermonkey.net/
// @run-at       document-end
// @supportURL   https://github.com/johnsyweb/tampermonkey-parkrun/issues/
// @tag          parkrun
// @version      1.0.30
// ==/UserScript==

(function () {
  'use strict';
  if (typeof module !== 'undefined' && module.exports) {
    module.exports = {
      calculatePIndex,
      extractEventDetails,
      findResultsTable,
    };
  } else {
    main();
  }
  function main() {
    const table = findResultsTable();
    if (!table) {
      console.error('Results table not found');
      return;
    }
    const eventDetails = extractEventDetails(table);
    const { pIndex, contributingEvents } = calculatePIndex(eventDetails);
    displayPIndex(pIndex, contributingEvents);
  }

  function displayPIndex(pIndex, contributingEvents) {
    const h2Element = document.querySelector('h2');
    if (h2Element) {
      const pIndexElement = document.createElement('div');
      pIndexElement.textContent = 'p-index: ' + pIndex;
      pIndexElement.style.fontSize = '1.5em';
      pIndexElement.style.fontWeight = 'bold';
      pIndexElement.style.marginTop = '10px';
      pIndexElement.style.backgroundColor = '#2b223d';
      pIndexElement.style.color = '#ffa300';
      pIndexElement.style.padding = '10px';
      pIndexElement.style.borderRadius = '5px';
      pIndexElement.style.display = 'flex';
      pIndexElement.style.flexDirection = 'column';
      pIndexElement.style.alignItems = 'center';
      pIndexElement.style.justifyContent = 'center';
      pIndexElement.setAttribute('id', 'p-index-display');

      const eventList = document.createElement('ul');
      eventList.style.listStyleType = 'none';
      eventList.style.padding = '0';
      contributingEvents.forEach((event) => {
        const listItem = document.createElement('li');
        listItem.textContent = event;
        listItem.style.fontWeight = 'normal';
        listItem.style.fontSize = '1em';
        eventList.appendChild(listItem);
      });
      pIndexElement.appendChild(eventList);

      h2Element.parentNode.insertBefore(pIndexElement, h2Element.nextSibling);

      setTimeout(() => {
        const rect = pIndexElement.getBoundingClientRect();
        const maxDimension = Math.max(rect.width, rect.height);
        pIndexElement.style.width = maxDimension + 'px';
        pIndexElement.style.height = maxDimension + 'px';
      }, 0);
    }
  }

  function extractEventDetails(table) {
    const eventDetails = [];
    const rows = table.querySelectorAll('tbody > tr');
    rows.forEach((row) => {
      const eventName = row.querySelector('td:nth-child(1) > a').textContent.trim();
      const date = row.querySelector('td:nth-child(2)').textContent.trim();
      const eventNumber = row.querySelector('td:nth-child(3)').textContent.trim();
      eventDetails.unshift({ eventName, date, eventNumber });
    });

    // Group event details by event name
    const groupedEvents = eventDetails.reduce((acc, { eventName, date, eventNumber }) => {
      if (!acc[eventName]) {
        acc[eventName] = [];
      }
      acc[eventName].push({ date, eventNumber });
      return acc;
    }, {});

    // Convert groupedEvents to an array of entries and sort by the number of visits
    const sortedGroupedEvents = Object.entries(groupedEvents).sort(
      (a, b) => b[1].length - a[1].length
    );

    return sortedGroupedEvents;
  }

  function findResultsTable() {
    const tables = document.querySelectorAll('#results');
    return tables[tables.length - 1];
  }

  function calculatePIndex(eventDetails) {
    const filteredGroupedEvents = eventDetails.filter(([, events], index) => events.length > index);
    const pIndex = filteredGroupedEvents.length;

    function convertDate(dateStr) {
      return new Date(dateStr.split('/').reverse().join('-'));
    }

    const contributingEvents = filteredGroupedEvents
      .map(([eventName, events]) => {
        const first = events[0];
        const pIndexReached = events[pIndex - 1];
        return {
          eventName,
          eventCount: events.length,
          firstDate: first.date,
          firstEventNumber: first.eventNumber,
          pIndexDate: pIndexReached.date,
          pIndexEventNumber: pIndexReached.eventNumber,
          firstDateForSorting: convertDate(first.date),
          pIndexDateForSorting: convertDate(pIndexReached.date),
        };
      })
      .sort((a, b) => a.pIndexDateForSorting - b.pIndexDateForSorting)
      .slice(0, pIndex)
      .map(
        (event) =>
          event.eventName +
          ' (' +
          event.eventCount +
          '): ' +
          event.firstDate +
          ' (#' +
          event.firstEventNumber +
          ') - ' +
          event.pIndexDate +
          ' (#' +
          event.pIndexEventNumber +
          ')'
      );

    return { pIndex, contributingEvents };
  }
})();