tlig-theme/src/demo/demo.js

// Demo page behaviour. Not a build input — see src/demo/demo.scss.
import '../sass/main.scss'
import './demo.scss'

// -- Colour swatches ---------------------------------------------------------
//
// Read from the emitted custom properties rather than from a hand-kept list, so
// the demo cannot drift from the stylesheet: delete a token and its swatch
// disappears on reload.

function emittedTokens (group) {
  const names = new Set()
  for (const sheet of document.styleSheets) {
    let rules
    try { rules = sheet.cssRules } catch { continue } // cross-origin
    for (const rule of rules) {
      if (rule.selectorText !== ':root') continue
      for (const prop of rule.style) {
        if (prop.startsWith(`--tlig-${group}-`)) names.add(prop)
      }
    }
  }
  return [...names]
}

function renderSwatches () {
  const root = getComputedStyle(document.documentElement)
  const html = emittedTokens('color').map((name) => {
    const value = root.getPropertyValue(name).trim()
    const short = name.replace('--tlig-color-', '')
    return `<figure class="swatch">
      <div class="swatch__chip"><div class="swatch__fill" style="background:${value}"></div></div>
      <figcaption class="swatch__meta">
        <div class="swatch__name">${short}</div>
        <div class="swatch__value">${value}</div>
      </figcaption>
    </figure>`
  }).join('')
  document.querySelector('#swatches').innerHTML = html
  document.querySelector('#swatch-count').textContent = emittedTokens('color').length
}

// -- Script switcher ---------------------------------------------------------
//
// The point of this control: all four papyrus files share one family name and
// are separated by unicode-range, so switching scripts changes no CSS at all.
// The browser picks the font file by codepoint.

const SAMPLES = {
  en: {
    label: 'English',
    heading: 'True Life in God',
    line: 'Peace be with you — I am the Alpha and the Omega.',
    note: 'Latin — PapyrusLETBold, the original file.',
  },
  hu: {
    // The pangram, not the site's own title: "Igaz Élet Istenben" contains no
    // codepoint above U+00FF, so it would be served by the Latin file and
    // would demonstrate nothing. ő (U+0151) and ű (U+0171) are the test.
    label: 'Magyar',
    heading: 'Árvíztűrő tükörfúrógép',
    line: 'Igaz Élet Istenben — ő and ű are what the Latin-Extended cut is for.',
    note: 'Latin Extended-A — the hu file. The original PapyrusLETBold has no ő or ű.',
  },
  bg: {
    label: 'Български',
    heading: 'Истински живот в Бога',
    line: 'Мир на вас — Аз съм Алфа и Омега.',
    note: 'Cyrillic — the cyrillic and bulgarian cuts.',
  },
  ru: {
    label: 'Русский',
    heading: 'Истинная жизнь в Боге',
    line: 'Мир вам — Я есмь Альфа и Омега.',
    note: 'Cyrillic — same file as Bulgarian, no extra rule.',
  },
  el: {
    label: 'Ελληνικά',
    heading: 'Αληθινή εν Θεώ Ζωή',
    line: 'Ειρήνη υμίν — Εγώ ειμι το Άλφα και το Ωμέγα.',
    note: 'No papyrus cut exists for Greek — this is the fallback face, shown honestly.',
  },
}

function setScript (code) {
  const sample = SAMPLES[code]
  if (!sample) return
  document.querySelector('#script-heading').textContent = sample.heading
  document.querySelector('#script-line').textContent = sample.line
  document.querySelector('#script-note').textContent = sample.note
  document.querySelector('#script-heading').lang = code
  for (const button of document.querySelectorAll('[data-script]')) {
    button.setAttribute('aria-pressed', String(button.dataset.script === code))
  }
}

// -- Breakpoint readout ------------------------------------------------------

function trackViewport () {
  const output = document.querySelector('#viewport')
  const update = () => {
    const width = window.innerWidth
    const name = width >= 1200 ? 'wide' : width >= 800 ? 'tablet' : 'phone'
    output.textContent = `${width}px · ${name}`
  }
  window.addEventListener('resize', update, { passive: true })
  update()
}

// -- Wire up -----------------------------------------------------------------

renderSwatches()
trackViewport()

// `?script=bg` opens straight onto a given script, so a particular cut can be
// linked to or screenshotted without clicking.
const requested = new URLSearchParams(location.search).get('script')
setScript(requested in SAMPLES ? requested : 'en')

for (const button of document.querySelectorAll('[data-script]')) {
  button.addEventListener('click', () => setScript(button.dataset.script))
}

const boxes = document.querySelector('#toggle-boxes')
boxes.addEventListener('click', () => {
  const on = document.body.classList.toggle('show-boxes')
  boxes.setAttribute('aria-pressed', String(on))
})