permalink.js

// permalink.js , project root

(function () {
  function ready(fn) {
    if (document.readyState === 'loading') {
      document.addEventListener('DOMContentLoaded', fn, { once: true });
    } else {
      fn();
    }
  }

  ready(() => {
    const incSel  = document.getElementById('inclusion');
    const fileSel = document.getElementById('filetype');
    const diffSel = document.getElementById('difference');
    const acCb    = document.getElementById('autoclose');
    const bustCb  = document.getElementById('bust');
    const blCb    = document.getElementById('applyBlocklist');
    const winCb   = document.getElementById('windowMode');
    const runBtn  = document.getElementById('run');
    const copyBtn = document.getElementById('copy-link');
    const copyToast = document.getElementById('copy-toast');

    if (!incSel || !fileSel || !diffSel || !runBtn) return;

    const params = new URLSearchParams(location.search);

    //helpers
    function truthy(v) { return v === '1' || v === 'true' || v === 'yes'; }

    function setSelectImmediate(el, value) {
      if (!value) return false;
      el.value = value;
      const ok = el.value === value;
      if (ok) el.dispatchEvent(new Event('change', { bubbles: true }));
      return ok;
    }

    function findMatchingOption(el, value) {
      if (!value) return null;
      const wanted = String(value).toLowerCase();
      const opts = Array.from(el.options || []);
      return opts.find(o =>
        (String(o.value).toLowerCase() === wanted) ||
        (String((o.textContent || '').trim()).toLowerCase() === wanted)
      ) || null;
    }

    //wait until the select has an option matching the value    
    function setSelectWhenOptionsLoaded(el, value, timeoutMs = 6000) {
      return new Promise(resolve => {
        if (!value) return resolve(false);

        const trySet = () => {
          const opt = findMatchingOption(el, value);
          if (opt) {
            el.value = opt.value;
            el.dispatchEvent(new Event('change', { bubbles: true }));
            resolve(true);
            return true;
          }
          return false;
        };

        if (trySet()) return;

        const mo = new MutationObserver(() => { trySet() && mo.disconnect(); });
        mo.observe(el, { childList: true, subtree: true });
        setTimeout(() => { try { mo.disconnect(); } catch {} resolve(false); }, timeoutMs);
      });
    }

    function buildShareURL({ includeRunFlag = false } = {}) {
      const p = new URLSearchParams();
      const inc  = incSel.value || '';
      const file = fileSel.value || '';
      const diff = diffSel.value || '';

      if (inc)  p.set('inc', inc);
      if (file) p.set('file', file);
      if (diff) p.set('diff', diff);

      if (acCb)   p.set('ac',   acCb.checked ? '1' : '0');
      if (bustCb) p.set('bust', bustCb.checked ? '1' : '0');
      if (blCb)   p.set('bl',   blCb.checked ? '1' : '0');
      if (winCb)  p.set('win',  winCb.checked ? '1' : '0');

      if (includeRunFlag) p.set('run', '1');

      return location.origin + location.pathname + '?' + p.toString();
    }

    function syncURL({ setRunFlag = false } = {}) {
      const qsURL = buildShareURL({ includeRunFlag: setRunFlag });
      const u = new URL(qsURL);
      if ('?' + u.searchParams.toString() !== location.search) {
        history.replaceState(null, '', qsURL);
      }
    }

    function wireLiveSync() {
      incSel.addEventListener('change', () => syncURL({ setRunFlag: false }));
      fileSel.addEventListener('change', () => syncURL({ setRunFlag: false }));
      diffSel.addEventListener('change', () => syncURL({ setRunFlag: false }));
      acCb?.addEventListener('change', () => syncURL({ setRunFlag: false }));
      bustCb?.addEventListener('change', () => syncURL({ setRunFlag: false }));
      blCb?.addEventListener('change', () => syncURL({ setRunFlag: false }));
      winCb?.addEventListener('change', () => syncURL({ setRunFlag: false }));

      //when the user clicks Run, stamp run=1 so sharing the URL autostarts the same config
      runBtn.addEventListener('click', () => syncURL({ setRunFlag: true }));
    }

    //strip query back to canonical base
    function stripURLToBase() {
      const base = location.origin + location.pathname;
      if (location.href !== base) {
        history.replaceState(null, '', base);
      }
    }

    //strip to base before app.js' run() opens popups
    runBtn.addEventListener('click', stripURLToBase, { capture: true });

    //copy link button
    copyBtn?.addEventListener('click', async () => {
      const url = buildShareURL({ includeRunFlag: true });
      try {
        await navigator.clipboard.writeText(url);
        if (copyToast) {
          copyToast.style.display = 'inline';
          setTimeout(() => { copyToast.style.display = 'none'; }, 1200);
        }
      } catch {
        //fallback, show the URL in a prompt
        window.prompt('Copy this link:', url);
      }
    });

    //apply from URL
    const incParam  = params.get('inc') || params.get('inclusion') || '';
    const fileParam = params.get('file') || params.get('filetype') || '';
    const diffParam = params.get('diff') || params.get('difference') || '';
    const winParam  = params.get('win');
    const autoRun   = truthy(params.get('run')) || truthy(params.get('autorun'));

    if (acCb)   acCb.checked   = truthy(params.get('ac')   ?? (acCb.checked ? '1' : '0'));
    if (bustCb) bustCb.checked = truthy(params.get('bust') ?? (bustCb.checked ? '1' : '0'));
    if (blCb)   blCb.checked   = truthy(params.get('bl')   ?? (blCb.checked ? '0' : '0'));
    if (winCb)  winCb.checked  = truthy(winParam ?? (winCb.checked ? '0' : '0'));

    //set inclusion and file immediately
    setSelectImmediate(incSel, incParam);
    setSelectImmediate(fileSel, fileParam);

    //ensure difference is selected after options load (async)
    setSelectWhenOptionsLoaded(diffSel, diffParam).then(() => {
      // if URL requested an autorun, click Run now.
      if (autoRun) {
        //strip the URL before the programmatic click
        stripURLToBase();
        // one microtask later so any other listeners settle
        setTimeout(() => runBtn.click(), 0);
      }
    });

    //keep URL in sync with future changes
    wireLiveSync();

    //if the page was opened without any params, initialize URL from defaults
    if (![incParam, fileParam, diffParam, params.get('ac'), params.get('bust'), params.get('bl'), params.get('win'), params.get('run')].some(Boolean)) {
      syncURL({ setRunFlag: false });
    }
  });
})();