usmt-dash/web/layout.js

/*
 * Layout helpers (see layout.css).
 *
 * Sticky headers: measures the top nav and each table's group header so the column
 * header rows can stick directly beneath them (--nav-h, --sticky-top, --thead-r1).
 *
 * Card view: on phones and tablets each table row is shown as a card, with every cell
 * rendered as "Column name: value". CSS can't look up a cell's column header, so this
 * copies each header's text onto its cells as data-label.
 *
 * The dashboard re-renders its tables constantly, so both are reapplied (once per frame
 * at most) whenever the DOM changes.
 */
(function () {
    'use strict';

    const cardsQuery = window.matchMedia('(max-width: 1100px)');
    const clean = text => text.replace(/[\u2195\u25B2\u25BC\u00D7\u2715]/g, '').replace(/\s+/g, ' ').trim();

    function labelTable(table) {
        const thead = table.tHead;
        if (!thead) return;

        // The header row is the one with the most text (Custom View has a drag-handle row above it)
        let headerRow = null, best = -1;
        for (const row of thead.rows) {
            if (row.classList.contains('filter-row')) continue;
            const named = Array.from(row.cells).filter(c => clean(c.textContent)).length;
            if (named > best) { best = named; headerRow = row; }
        }
        if (!headerRow) return;

        for (const row of thead.rows) {
            if (row === headerRow) row.classList.add('card-label-row');
            else if (!row.classList.contains('filter-row')) row.classList.add('card-aux-row');
        }

        const labels = Array.from(headerRow.cells).map(c => clean(c.textContent));
        const apply = row => {
            Array.from(row.cells).forEach((cell, i) => {
                const label = cell.colSpan > 1 ? '' : (labels[i] || '');
                if (cell.dataset.label !== label) cell.dataset.label = label;
            });
        };
        thead.querySelectorAll('tr.filter-row').forEach(apply);
        for (const body of table.tBodies) for (const row of body.rows) apply(row);

        addFilterToggle(table, thead.querySelector('tr.filter-row'));
    }

    // Column filters take a lot of room above every card group, so they fold behind a
    // button that also shows how many filters are active.
    function addFilterToggle(table, filterRow) {
        if (!filterRow) return;
        let btn = table.previousElementSibling;
        if (!btn || !btn.classList.contains('card-filter-toggle')) {
            btn = document.createElement('button');
            btn.type = 'button';
            btn.className = 'card-filter-toggle';
            btn.addEventListener('click', () => { table.classList.toggle('show-filters'); updateToggle(table, btn); });
            table.parentNode.insertBefore(btn, table);
            filterRow.addEventListener('input', () => updateToggle(table, btn));
            filterRow.addEventListener('change', () => updateToggle(table, btn));
        }
        updateToggle(table, btn);
    }
    function updateToggle(table, btn) {
        const row = table.tHead && table.tHead.querySelector('tr.filter-row');
        if (!row) return;
        const active = Array.from(row.querySelectorAll('input[type="text"]')).filter(i => i.value.trim()).length
                     + row.querySelectorAll('input[type="checkbox"]:checked').length;
        const open = table.classList.contains('show-filters');
        const html = `${open ? 'Hide' : 'Show'} filters${active ? ` <span class="count">${active}</span>` : ''}`;
        if (btn.innerHTML !== html) btn.innerHTML = html;
    }

    // --- Sticky offsets ---------------------------------------------------------------
    function setVar(el, name, value) {
        if (el.style.getPropertyValue(name) !== value) el.style.setProperty(name, value);
    }
    function groupHeaderFor(table) {
        // The group header is a sibling of the table or of its wrapper
        for (let el = table.parentElement, depth = 0; el && depth < 3; el = el.parentElement, depth++) {
            const gh = el.querySelector(':scope > .group-header');
            if (gh) return gh;
        }
        return null;
    }
    function updateSticky() {
        const root = document.documentElement;
        const nav = document.querySelector('.top-nav');
        const navH = nav ? nav.getBoundingClientRect().height : 60;
        setVar(root, '--nav-h', navH + 'px');
        const dock = document.getElementById('usmt-term');
        setVar(root, '--dock-h', (dock ? Math.ceil(dock.getBoundingClientRect().height) : 0) + 'px');

        document.querySelectorAll('table.master-table').forEach(table => {
            if (!table.offsetParent) return;                    // hidden page/group: keep old values
            const gh = groupHeaderFor(table);
            const ghH = gh && getComputedStyle(gh).position === 'sticky' ? gh.getBoundingClientRect().height : 0;
            // 1px overlap tucks the table header under the group header: no hairline gap
            setVar(table, '--sticky-top', Math.max(0, navH + ghH - 1) + 'px');
        });
    }

    let queued = false;
    function run() {
        queued = false;
        updateSticky();
        if (!cardsQuery.matches) return;
        document.querySelectorAll('table.master-table').forEach(labelTable);
    }
    function schedule() {
        if (queued) return;
        queued = true;
        requestAnimationFrame(run);
    }

    function start() {
        new MutationObserver(schedule).observe(document.body, { childList: true, subtree: true });
        if (cardsQuery.addEventListener) cardsQuery.addEventListener('change', schedule);
        else cardsQuery.addListener(schedule);
        window.addEventListener('resize', schedule);
        // Groups and pages are shown by toggling display (not a DOM change), so also
        // re-measure as the user scrolls; writes only happen when a value changes.
        window.addEventListener('scroll', schedule, { passive: true });
        // The terminal dock opens, closes and resizes without a page resize
        if (window.ResizeObserver) {
            const watchDock = () => {
                const dock = document.getElementById('usmt-term');
                if (dock) new ResizeObserver(schedule).observe(dock); else setTimeout(watchDock, 500);
            };
            watchDock();
        }
        schedule();
    }
    if (document.readyState === 'loading') document.addEventListener('DOMContentLoaded', start);
    else start();
})();