Coupons: a "Remind me" link for a code's end (plan L48 R3) (#172)

ddiff --git a/server/http/public.js b/server/http/public.js
iindex 72d7cde..a861cf1 100644
---- a/server/http/public.js
++++ b/server/http/public.js
@@@ -338,7 +338,7 @@ function createPublicRoutes(ctx) {
              title: `${v.code} — ${v.title} at ${m.name}`,
              description: couponDescription(v, m),
              decision: publication.couponDecision(c, m), canonical: v.url, jsonLd: jsonLd(m, v),
--            body: pages.couponPage({ v, m, history: await coupons.history(c.id), weeks: await coupons.reportWeeks(c.id), viewer: req.viewer, csrf: csrf(req), back: `/c/${c.id}`, flashMsg }), chart: true,
++            body: pages.couponPage({ v, m, history: await coupons.history(c.id), weeks: await coupons.reportWeeks(c.id), viewer: req.viewer, csrf: csrf(req), back: `/c/${c.id}`, flashMsg, now: store.now() }), chart: true,
          }, { cacheable: !flashMsg });
      });
  
ddiff --git a/server/render/home.js b/server/render/home.js
iindex cca4af0..afb5c5f 100644
---- a/server/render/home.js
++++ b/server/render/home.js
@@@ -11,6 +11,7 @@
  const ssr = require('openvibe-publishing/ssr');
  const showcase = require('openvibe-shared/showcase');
  const { STATUS_LABEL, shopsSection } = require('./pages');
++const { remindLink } = require('./remind');
  // The short home (the owner's rule, 2026-10-30): the three code lists become one pick block, a row of chips picks
  // one of them, and the parts a reader rarely needs become folds.
  const { pickBlock, foldBlock } = require('./short');
@@@ -31,11 +32,15 @@ function until(iso, now) {
  function codeCard(v, m, now) {
      const min = (v.restrictions || []).find((r) => r.kind === 'min_spend');
      const rules = [min ? `Minimum spend ${min.amount}` : null, (v.restrictions || []).some((r) => r.kind === 'new_customers_only') ? 'New customers only' : null].filter(Boolean);
++    // "Remind me" for the moment the code ends (plan L48 R3): a quiet link in the card's own line, only when the end
++    // is known and still ahead.
++    const remind = remindLink(v, { now, shop: m.name });
      return h`<li class="cp-card">
  <p class="cp-top"><a class="cp-shop" href="/m/${m.slug}">${m.name}</a> <span class="status status-${v.status}">${STATUS_LABEL[v.status] || v.status}</span></p>
  <p class="cp-code"><span class="sr-only">Code: </span><code class="code">${v.code}</code></p>
  <h3><a href="/c/${v.id}">${v.title}</a></h3>
  <p class="meta">${v.expiry.known ? h`Ends <time datetime="${v.expiry.expires_at}" title="${v.expiry.expires_at.slice(0, 16).replace('T', ' ')} UTC">${until(v.expiry.expires_at, now)}</time>` : h`<span class="unknown">No end date stated</span>`}${rules.length ? h` · ${rules.join(' · ')}` : ''}</p>
++${remind ? h`<p class="meta">${raw(remind)}</p>` : ''}
  ${v.attribution ? h`<p class="meta cp-via">via <a href="${v.attribution.url}" rel="nofollow noopener">${v.attribution.text}</a></p>` : ''}
  </li>`;
  }
ddiff --git a/server/render/pages.js b/server/render/pages.js
iindex ac3d7b9..0f1cd3b 100644
---- a/server/render/pages.js
++++ b/server/render/pages.js
@@@ -10,6 +10,7 @@
   */
  const ssr = require('openvibe-publishing/ssr');
  const kit = require('openvibe-shared/kit');
++const { remindLink } = require('./remind');
  
  const { html: h, raw } = ssr;
  const k = (markup) => raw(String(markup));   // a kit builder's markup (already escaped) inside an h`` template
@@@ -171,17 +172,21 @@ function quickReport(v, { viewer, csrf, back }) {
      return h`<div class="cpn-report"><span>Did it work?</span>${one('worked', 'It worked')}${one('failed', "It didn't")}</div>`;
  }
  
--/** One code. v: coupons.view(); opts: { viewer, csrf, back, link, page, shopUrl } (page: its own page, where the title is the h1) */
++/** One code. v: coupons.view(); opts: { viewer, csrf, back, link, page, shopUrl, now, shop } (page: its own page, where the title is the h1) */
  function couponCard(v, opts = {}) {
      const title = opts.link ? h`<a href="/c/${v.id}">${v.title}</a>` : v.title;
      // The currency the code states for its money, shown beside the amount on the code's own page: the page
      // says which currency it is in, and the page's structured data claims nothing more than that.
      const currency = opts.page ? currencyOf(v, moneyOf(v)) : null;
++    // "Remind me" for the moment the code ends (plan L48 R3): on the code's own page it sits with the other actions,
++    // on a card it is a quiet link in the card's own line. Only when the end is known and still ahead.
++    const remind = remindLink(v, { now: opts.now, shop: opts.shop });
      return h`<article class="coupon cpn cpn--${v.status}" id="${v.id}">
  <div class="cpn-top"><strong class="cpn-off">${headline(v)}</strong>${isProductDeal(v) ? h`<span class="cpn-scope">One product</span>` : ''}${currency ? h`<span class="cpn-scope">${currency}</span>` : ''}</div>
  ${opts.page ? h`<h1 class="coupon-title">${title}</h1>` : h`<h3 class="cpn-title">${title}</h3>`}
--<div class="cpn-code"><code class="code" id="code-${v.id}">${v.code}</code>${k(kit.iconButton({ type: 'button', icon: 'copy', label: `Copy ${v.code}`, attrs: { 'data-ovk-copy': `#code-${v.id}`, hidden: true } }))}${opts.shopUrl ? k(kit.button({ href: opts.shopUrl, label: 'Shop', icon: 'open', kind: 'quiet', small: true, attrs: { rel: 'nofollow noopener', target: '_blank' } })) : ''}</div>
++<div class="cpn-code"><code class="code" id="code-${v.id}">${v.code}</code>${k(kit.iconButton({ type: 'button', icon: 'copy', label: `Copy ${v.code}`, attrs: { 'data-ovk-copy': `#code-${v.id}`, hidden: true } }))}${opts.shopUrl ? k(kit.button({ href: opts.shopUrl, label: 'Shop', icon: 'open', kind: 'quiet', small: true, attrs: { rel: 'nofollow noopener', target: '_blank' } })) : ''}${opts.page && remind ? k(remind) : ''}</div>
  ${statusLine(v)}
++${!opts.page && remind ? h`<p class="meta">${k(remind)}</p>` : ''}
  ${restrictionChips(v.restrictions)}
  ${quickReport(v, opts)}
  <details class="cpn-more"${opts.page ? ' open' : ''}><summary>Details</summary>
@@@ -303,11 +308,11 @@ function merchantTrend(trend, name) {
  <p class="meta">A week with fewer than ${trend.min_people} people is too few to show, so it stays blank.</p>`);
  }
  
--function couponPage({ v, m, history, weeks, viewer, csrf, back, flashMsg }) {
++function couponPage({ v, m, history, weeks, viewer, csrf, back, flashMsg, now = Date.now() }) {
      return h`${raw(ssr.breadcrumbsHtml([{ name: 'Coupons', url: '/' }, { name: m.name, url: `/m/${m.slug}` }, { name: v.code }]))}
  ${flash(flashMsg)}
  ${v.active ? '' : h`<p class="notice">This code is not in active results (${STATUS_LABEL[v.status] ? STATUS_LABEL[v.status].toLowerCase() : v.status}${v.expiry.known && !v.active && v.status !== 'expired' ? ', past its expiry' : ''}).</p>`}
--${couponCard(v, { viewer, csrf, back, page: true })}
++${couponCard(v, { viewer, csrf, back, page: true, now, shop: m.name })}
  <p class="cpn-people">${peopleLine(v)}</p>
  ${reportTrend(weeks)}
  <h2>Status history</h2>
ddiff --git a/server/render/remind.js b/server/render/remind.js
nnew file mode 100644
iindex 0000000..efd784a
---- /dev/null
++++ b/server/render/remind.js
@@@ -0,0 +1,53 @@
++'use strict';
++
++/**
++ * "Remind me" on a code's end (plan L48 R3): a link to openvibe.today/remind that sets a one-off reminder for the
++ * moment the code ends. The person signs in there, picks how long before, and it reaches them in the bell and as a
++ * push on every OpenVibe site.
++ *
++ * The link is only there when the end is known and still ahead: a code that ended, or one nobody dated, gets none.
++ * The instant is the end itself, in UTC (a stated day means the end of that day in UTC, as the page says).
++ */
++const kit = require('openvibe-shared/kit');
++
++const HOST = 'openvibe.coupons';
++const REMIND = 'https://openvibe.today/remind';
++
++/** The moment a code ends, in UTC, or null when nobody stated an end. */
++function endsAt(v) {
++    const e = v && v.expiry;
++    if (!e || !e.known || !e.expires_at) return null;
++    const ms = Date.parse(e.expires_at);
++    return Number.isFinite(ms) ? new Date(ms).toISOString() : null;
++}
++
++/** The reminder's title: the code's own name, the shop it is at, and that it ends. */
++function remindTitle(v, shop = '') {
++    const name = String(v && v.title ? v.title : '').trim();
++    const where = String(shop || '').trim();
++    return where ? `${name} at ${where} ends` : `${name} ends`;
++}
++
++/** Today's "Remind me" link for this code, or '' when there is nothing to remind about. */
++function remindHref(v, { now = Date.now(), shop = '', url = '' } = {}) {
++    const at = endsAt(v);
++    if (!at || Date.parse(at) <= now) return '';
++    const query = new URLSearchParams({ title: remindTitle(v, shop), at, url: url || (v && v.url) || '', from: HOST });
++    return `${REMIND}?${query}`;
++}
++
++/** The link, as a quiet small button. */
++function remindLink(v, opts = {}) {
++    const href = remindHref(v, opts);
++    if (!href) return '';
++    return kit.button({ href, label: 'Remind me', icon: 'bell', kind: 'quiet', small: true });
++}
++
++/** The same link as a bell only, for a row that has no room for words. */
++function remindIcon(v, opts = {}) {
++    const href = remindHref(v, opts);
++    if (!href) return '';
++    return kit.iconButton({ href, icon: 'bell', label: 'Remind me' });
++}
++
++module.exports = { endsAt, remindTitle, remindHref, remindLink, remindIcon, HOST, REMIND };
ddiff --git a/server/render/store.js b/server/render/store.js
iindex 0e4791d..e2e0981 100644
---- a/server/render/store.js
++++ b/server/render/store.js
@@@ -22,6 +22,7 @@ const k = (markup) => raw(String(markup));
  const esc = (s) => String(s == null ? '' : s).replace(/[&<>"']/g, (c) => ({ '&': '&amp;', '<': '&lt;', '>': '&gt;', '"': '&quot;', "'": '&#39;' }[c]));
  
  const { isProductDeal, headline, shopTab, merchantTrend, couponCard, regionName, BASIS_LABEL } = require('./pages');
++const { remindLink, remindIcon } = require('./remind');
  
  const MONTHS = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'];
  /** Below this many reports a code's rate is not shown at all: the page says only that validity is unknown. */
@@@ -133,34 +134,39 @@ function reportForms(v, { csrf, back }) {
  }
  
  /** The best code, first on the page: the code in a dashed box, its rate, when it was last reported and its expiry. */
--function bestCard(v, { now, windowDays, csrf, back }) {
++function bestCard(v, { now, windowDays, csrf, back, shop = '' }) {
      const lr = lastReport(v, now, windowDays);
      const ex = expiryOf(v);
      const limits = restrictionText(v.restrictions);
      const codeId = v.id;
++    // "Remind me" for the moment the code ends (plan L48 R3): only when the end is known and still ahead.
++    const remind = remindLink(v, { now, shop });
      return h`<section class="cpn-best-card" id="cpn-best-card" aria-labelledby="cpn-best-h">
  <h2 class="cpn-best-label" id="cpn-best-h">Best code right now</h2>
  <p class="cpn-best-head"><strong class="cpn-off">${headline(v)}</strong> <a class="cpn-best-title" href="/c/${v.id}">${v.title}</a></p>
  <div class="cpn-codebox"><code class="cpn-codetext" id="${codeId}">${v.code}</code>${k(copyButton(codeId))}</div>
  <p class="cpn-status-line">${statusText(v)}</p>
  <p class="cpn-meta">${lr.iso ? h`<time datetime="${lr.iso}">${lr.text}</time>` : lr.text}</p>
--<p class="cpn-meta">${ex ? h`${ex.short}${ex.said ? h` (${ex.said})` : ''}` : h`<span class="unknown">Expiry unknown</span>`}</p>
++<p class="cpn-meta">${ex ? h`${ex.short}${ex.said ? h` (${ex.said})` : ''}` : h`<span class="unknown">Expiry unknown</span>`}${remind ? k(remind) : ''}</p>
  ${limits.length ? h`<p class="cpn-meta cpn-limits">${limits.join(' · ')}</p>` : h`<p class="cpn-meta cpn-limits">No restrictions stated. That does not mean there are none.</p>`}
  <div class="cpn-votes">${reportForms(v, { csrf, back })}</div>
  </section>`;
  }
  
  /** One code as a compact row: the code, the same facts and the same buttons. */
--function codeRow(v, { now, windowDays, csrf, back }) {
++function codeRow(v, { now, windowDays, csrf, back, shop = '' }) {
      const lr = lastReport(v, now, windowDays);
      const ex = expiryOf(v);
      const facts = [statusText(v), lr.text, ex ? (ex.said ? `${ex.short} (${ex.said})` : ex.short) : 'Expiry unknown'];
      const limits = restrictionText(v.restrictions);
      const codeId = v.id;
++    // "Remind me" for the moment the code ends (plan L48 R3), with the row's other actions; only when the end is
++    // known and still ahead. The row is narrow, so the link is the bell alone.
++    const remind = remindIcon(v, { now, shop });
      return kit.row({
          titleHtml: `<a class="cpn-row-code" href="/c/${v.id}"><code>${esc(v.code)}</code></a> <span class="cpn-row-off">${esc(headline(v))}</span>`,
          subHtml: `<span class="cpn-row-facts">${esc(facts.join(' · '))}</span>${limits.length ? `<span class="cpn-row-limits">${esc(limits.join(' · '))}</span>` : ''}`,
--        trail: `${copyButton(codeId, { small: true, kind: 'quiet' })}${reportForms(v, { csrf, back })}`,
++        trail: `${copyButton(codeId, { small: true, kind: 'quiet' })}${remind}${reportForms(v, { csrf, back })}`,
      });
  }
  
@@@ -248,7 +254,7 @@ function storePage({ m, domains, hints, codes, deals, ended, reportsThisWeek, pr
          body = h`${aboutTab({ m, domains, hints, codes: all, price, now, windowDays })}`;
      } else if (tab === 'deals') {
          body = h`<p class="ovk-note cpn-lede">Codes that take money off one product, as the source posted them.</p>
--${deals.length ? h`${deals.slice(0, shown).map((v) => couponCard(v, { viewer, csrf, back, link: true, shopUrl: m.homepage_url }))}
++${deals.length ? h`${deals.slice(0, shown).map((v) => couponCard(v, { viewer, csrf, back, link: true, shopUrl: m.homepage_url, now, shop: m.name }))}
  ${shown < deals.length ? h`<p class="cpn-more"><a class="ovk-btn ovk-btn--quiet" href="${base}?tab=deals&amp;deals=${String(Math.min(deals.length, shown + DEALS_PAGE))}">Show ${String(Math.min(DEALS_PAGE, deals.length - shown))} more <span class="cpn-muted">(${String(shown)} of ${String(deals.length)})</span></a></p>` : ''}` : h`<p class="empty">No product deals for ${m.name} right now.</p>`}
  ${merchantTrend(success, m.name)}`;
      } else if (!codes.length) {
@@@ -261,8 +267,8 @@ ${deals.length ? h`<p class="ovk-note">${String(deals.length)} product deal${dea
  </section>
  ${ended.length ? k(kit.fold({ title: 'Expired', meta: String(ended.length), body: String(kit.list(ended.map(endedRow))) })) : ''}`;
      } else {
--        body = h`${best ? bestCard(best, { now, windowDays, csrf, back }) : ''}
--${others.length ? k(`<div class="cpn-list">${kit.list(others.map((v) => codeRow(v, { now, windowDays, csrf, back })), { title: 'Other codes' })}</div>`) : ''}
++        body = h`${best ? bestCard(best, { now, windowDays, csrf, back, shop: m.name }) : ''}
++${others.length ? k(`<div class="cpn-list">${kit.list(others.map((v) => codeRow(v, { now, windowDays, csrf, back, shop: m.name })), { title: 'Other codes' })}</div>`) : ''}
  ${merchantTrend(success, m.name)}
  <p class="cpn-submit">${k(kit.button({ href: `/submit?merchant=${encodeURIComponent(m.slug)}`, label: `Submit a code for ${m.name}`, icon: 'plus', kind: 'quiet', small: true }))}</p>
  ${ended.length ? k(kit.fold({ title: 'Expired', meta: String(ended.length), body: String(kit.list(ended.map(endedRow))) })) : ''}`;
ddiff --git a/test/remind-links.test.js b/test/remind-links.test.js
nnew file mode 100644
iindex 0000000..c459f54
---- /dev/null
++++ b/test/remind-links.test.js
@@@ -0,0 +1,68 @@
++'use strict';
++/**
++ * "Remind me" on a code's end (plan L48 R3): the link to openvibe.today/remind on the code's own page and on the cards
++ * that show the end, with the right title, time and page — and no link at all once the end has passed.
++ */
++const assert = require('assert');
++
++const { boot, check, done } = require('./helpers/boot');
++
++/** Every "Remind me" link on a page, as the URL it points at. */
++function remindLinks(html) {
++    return [...String(html).matchAll(/href="(https:\/\/openvibe\.today\/remind\?[^"]+)"/g)]
++        .map((m) => m[1].replace(/&amp;/g, '&'));
++}
++const query = (href) => Object.fromEntries(new URL(href).searchParams);
++
++(async () => {
++    const t = await boot();
++    const alice = t.network.addUser('alice');
++    const shop = await t.merchant({ name: 'Green Grocer', host: 'greengrocer.co.uk' });
++
++    await check('a code that ends later links to Today\'s "Remind me" on its page and on the cards', async () => {
++        const r = await t.submit(alice, { merchant_id: shop.id, code: 'VEG5', title: 'Five pounds off veg boxes', expires: '2026-12-01' });
++        assert.strictEqual(r.status, 201, r.text.slice(0, 300));
++        const id = r.json().coupon.id;
++
++        const page = await t.get(`/c/${id}`);
++        const links = remindLinks(page.text);
++        assert.ok(links.length, 'the code\'s own page has a "Remind me" link');
++        const q = query(links[0]);
++        assert.strictEqual(q.title, 'Five pounds off veg boxes at Green Grocer ends');
++        assert.strictEqual(q.at, '2026-12-01T23:59:59.999Z', 'the end itself, in UTC');
++        assert.strictEqual(q.url, `https://openvibe.coupons/c/${id}`, 'the code\'s canonical page');
++        assert.strictEqual(q.from, 'openvibe.coupons');
++
++        const home = await t.get('/');
++        const homeLink = remindLinks(home.text).find((h) => query(h).url === `https://openvibe.coupons/c/${id}`);
++        assert.ok(homeLink, 'the front page\'s card has the link too');
++        assert.strictEqual(query(homeLink).at, '2026-12-01T23:59:59.999Z');
++
++        const store = await t.get(`/m/${shop.slug}`);
++        const storeLink = remindLinks(store.text).find((h) => query(h).url === `https://openvibe.coupons/c/${id}`);
++        assert.ok(storeLink, 'the shop page\'s row has the link too');
++        assert.strictEqual(query(storeLink).title, 'Five pounds off veg boxes at Green Grocer ends');
++    });
++
++    await check('a code with no stated end has no "Remind me" link', async () => {
++        const r = await t.submit(alice, { merchant_id: shop.id, code: 'NODATE', title: 'Ten percent off anything' });
++        assert.strictEqual(r.status, 201, r.text.slice(0, 300));
++        const id = r.json().coupon.id;
++        const page = await t.get(`/c/${id}`);
++        assert.strictEqual(remindLinks(page.text).length, 0, 'no link without an end');
++    });
++
++    await check('a code that has ended has no "Remind me" link', async () => {
++        const r = await t.submit(alice, { merchant_id: shop.id, code: 'GONE', title: 'Half off the lot' });
++        assert.strictEqual(r.status, 201, r.text.slice(0, 300));
++        const id = r.json().coupon.id;
++        // The end moves into the past: nobody may be reminded for a code that is over.
++        await t.ctx.store.db.prepare('UPDATE coupons SET expires_at = ?, expires_precision = ? WHERE id = ?')
++            .run(t.clock.now() - 60_000, 'instant', id);
++        const page = await t.get(`/c/${id}`);
++        assert.strictEqual(remindLinks(page.text).length, 0, 'no link once the end has passed');
++    });
++
++    await t.close();
++    done();
++})();