Add study account engagement features; v1.2.4

- Pause reminders: remindersPausedUntil field + scheduler skip + account UI with 7/14/30-day presets
- Email digest mode: reminderFrequency field (immediate/weekly) + weekly digest email + scheduler + account UI toggle
- Admin user list improvements: streak, reengagement, frequency, pause, per-study lesson progress
- Admin manual re-engagement: POST endpoint + tier selector button in admin panel
- Study bookmarks: bookmarkedSectionIds in progress file + POST/DELETE endpoints + toggle button in lesson UI
- Study completion certificate email: auto-sent on first certificate issuance
- Content fields for certificate and weekly digest email templates in admin

Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>

server/data.js

@@ -1415,6 +1415,9 @@ export function sanitizeStudyUsers(value) {
       totpEnabledAt: typeof item?.totpEnabledAt === 'string' ? item.totpEnabledAt : null,
       totpRecoveryCodes: Array.isArray(item?.totpRecoveryCodes) ? item.totpRecoveryCodes.filter(h => typeof h === 'string') : [],
       totpSecretPending: typeof item?.totpSecretPending === 'string' ? item.totpSecretPending : undefined,
+      remindersPausedUntil: typeof item?.remindersPausedUntil === 'string' ? item.remindersPausedUntil : null,
+      reminderFrequency: item?.reminderFrequency === 'weekly' ? 'weekly' : 'immediate',
+      weeklyDigestSentAt: typeof item?.weeklyDigestSentAt === 'string' ? item.weeklyDigestSentAt : null,
     })
   }
   return out.slice(0, MAX_STUDY_USERS)
@@ -1459,8 +1462,12 @@ export function sanitizeStudyProgress(value) {
             ])
         )
         : {}
+      const bookmarkedSectionIds = Array.isArray(studyData?.bookmarkedSectionIds)
+        ? Array.from(new Set(studyData.bookmarkedSectionIds.filter(id => typeof id === 'string' && id.trim()).map(id => id.trim())))
+        : []
       progress.byStudy[studySlug.trim().toLowerCase()] = {
         completedSectionIds: Array.from(new Set(completedSectionIds)),
+        bookmarkedSectionIds,
         quizAnswers,
       }
     }

server/email.js

@@ -635,3 +635,80 @@ export async function sendStudyReengagementEmail(email, displayName, studyTitle,
     console.error('[study-reengagement] send exception:', err)
   }
 }
+
+export async function sendStudyCertificateEmail(email, displayName, studyTitle, certUrl) {
+  if (!process.env.RESEND_API_KEY) return
+  try {
+    const resend = new Resend(process.env.RESEND_API_KEY)
+    const cfg = state.cachedSiteContent ?? {}
+    const namePart = typeof displayName === 'string' && displayName.trim() ? displayName.trim() : 'friend'
+    const subject = cfg.studyCertificateEmailSubject?.trim() || 'Your certificate is ready'
+    const bodyText = cfg.studyCertificateEmailBody?.trim() || 'Congratulations — you have completed every lesson in this study. Your certificate is ready to view and share.'
+    const ctaLabel = cfg.studyCertificateEmailCtaLabel?.trim() || 'View Certificate'
+    const signoff = cfg.studyCertificateEmailSignoff?.trim() || 'Grace and peace,\nVerse by Verse with Nate'
+    const bodyHtml = (
+      `<p style="margin:0 0 16px;">Congratulations, <strong style="color:#f0ead8;">${escapeHtml(namePart)}</strong>!</p>` +
+      `<p style="margin:0 0 16px;">${escapeHtml(bodyText)}</p>` +
+      `<p style="margin:0 0 16px;color:#c9a84c;font-weight:700;">${escapeHtml(studyTitle)}</p>`
+    )
+    const footerHtml = `<p style="margin:0;font-family:Georgia,serif;font-size:12px;font-weight:300;color:#7a7060;line-height:1.6;">${escapeHtml(signoff).replace(/\n/g, '<br/>')}</p>`
+    const { error } = await resend.emails.send({
+      from: process.env.RESEND_FROM ?? DEFAULT_RESEND_FROM,
+      to: [email],
+      subject,
+      text: `Congratulations, ${namePart}!\n\n${bodyText}\n\n${studyTitle}\n\nView your certificate: ${certUrl}\n\n${signoff}`,
+      html: buildBrandedEmailHtml({
+        title: 'Study Complete',
+        eyebrow: 'Certificate of Completion',
+        bodyHtml,
+        ctaLabel,
+        ctaUrl: certUrl,
+        footerHtml,
+      }),
+    })
+    if (error) console.error('[study-certificate] email send error:', error)
+  } catch (err) {
+    console.error('[study-certificate] email exception:', err)
+  }
+}
+
+export async function sendStudyWeeklyDigestEmail(email, displayName, lessons, unsubUrl) {
+  if (!process.env.RESEND_API_KEY) return
+  try {
+    const resend = new Resend(process.env.RESEND_API_KEY)
+    const cfg = state.cachedSiteContent ?? {}
+    const namePart = typeof displayName === 'string' && displayName.trim() ? displayName.trim() : 'friend'
+    const subject = cfg.studyWeeklyDigestEmailSubject?.trim() || 'Your weekly study digest'
+    const introText = cfg.studyWeeklyDigestEmailBody?.trim() || 'Here are the lessons released this week in your study track. Open any to continue where you left off.'
+    const signoff = cfg.studyWeeklyDigestEmailSignoff?.trim() || 'Grace and peace,\nVerse by Verse with Nate'
+    const lessonListHtml = lessons.map(l =>
+      `<p style="margin:0 0 12px;"><a href="${escapeHtml(l.sectionUrl)}" style="color:#c9a84c;text-decoration:none;font-weight:700;">${escapeHtml(l.sectionTitle)}</a>` +
+      (l.sectionReference ? ` <span style="color:#7a7060;">(${escapeHtml(l.sectionReference)})</span>` : '') +
+      (l.studyTitle ? ` <span style="color:#7a7060;font-size:0.9em;">— ${escapeHtml(l.studyTitle)}</span>` : '') +
+      `</p>`
+    ).join('')
+    const lessonListText = lessons.map(l => `• ${l.sectionTitle}${l.sectionReference ? ` (${l.sectionReference})` : ''}: ${l.sectionUrl}`).join('\n')
+    const bodyHtml = (
+      `<p style="margin:0 0 16px;">Hi <strong style="color:#f0ead8;">${escapeHtml(namePart)}</strong>,</p>` +
+      `<p style="margin:0 0 20px;">${escapeHtml(introText)}</p>` +
+      `<div style="border-left:2px solid #2a2518;padding-left:16px;">${lessonListHtml}</div>`
+    )
+    const unsubLine = unsubUrl ? `<p style="margin:16px 0 0;font-size:11px;color:#7a7060;">Not interested? <a href="${escapeHtml(unsubUrl)}" style="color:#7a7060;">Unsubscribe from these reminders.</a></p>` : ''
+    const footerHtml = `<p style="margin:0;font-family:Georgia,serif;font-size:12px;font-weight:300;color:#7a7060;line-height:1.6;">${escapeHtml(signoff).replace(/\n/g, '<br/>')}</p>${unsubLine}`
+    const { error } = await resend.emails.send({
+      from: process.env.RESEND_FROM ?? DEFAULT_RESEND_FROM,
+      to: [email],
+      subject,
+      text: `Hi ${namePart},\n\n${introText}\n\n${lessonListText}\n\n${signoff}${unsubUrl ? `\n\nUnsubscribe: ${unsubUrl}` : ''}`,
+      html: buildBrandedEmailHtml({
+        title: 'Weekly Study Digest',
+        eyebrow: 'Study Reminder',
+        bodyHtml,
+        footerHtml,
+      }),
+    })
+    if (error) console.error('[study-digest] send error:', error)
+  } catch (err) {
+    console.error('[study-digest] send exception:', err)
+  }
+}

server/routes/admin-assets.js

@@ -9,6 +9,7 @@ import {
   readUploadsMetadata,
   writeUploadsMetadata,
   getUserNotesFilePath,
+  loadUserProgress,
   queueStudyUsersWrite,
 } from '../data.js'
 import {
@@ -16,7 +17,9 @@ import {
   getStudyCatalog,
   normalizeStudySlug,
   isEnrollableStudySlug,
+  makeUnsubUrl,
 } from '../study-helpers.js'
+import { sendStudyReengagementEmail } from '../email.js'
 
 export function register(app) {
   app.get('/api/admin-assets', requireAdminAuth, async (_req, res) => {
@@ -117,9 +120,19 @@ export function register(app) {
         noteCount = Object.values(notes).filter(n => typeof n === 'string' && n.trim()).length
       } catch { /* ignore */ }
 
+      let progressByStudy = {}
+      try {
+        const prog = await loadUserProgress(user.id)
+        for (const [slug, data] of Object.entries(prog.byStudy)) {
+          progressByStudy[slug] = { completedLessons: (data.completedSectionIds ?? []).length }
+        }
+      } catch { /* ignore */ }
+
       const enrolledStudies = (user.enrolledStudySlugs ?? []).map(slug => {
         const study = catalog.find(s => s.slug === slug)
-        return study ? { slug, title: study.title } : { slug, title: slug }
+        return study
+          ? { slug, title: study.title, completedLessons: progressByStudy[slug]?.completedLessons ?? 0 }
+          : { slug, title: slug, completedLessons: 0 }
       })
 
       return {
@@ -132,12 +145,50 @@ export function register(app) {
         noteCount,
         subscribeNewsletter: user.subscribeNewsletter !== false,
         studyRemindersEnabled: user.studyRemindersEnabled === true,
+        reminderFrequency: user.reminderFrequency ?? 'immediate',
+        remindersPausedUntil: user.remindersPausedUntil ?? null,
+        currentStreak: user.currentStreak ?? 0,
+        longestStreak: user.longestStreak ?? 0,
+        reengagementSentAt: user.reengagementSentAt ?? {},
       }
     }))
 
     res.json({ users })
   })
 
+  app.post('/api/admin/study-users/:id/send-reengagement', requireAdminAuth, async (req, res) => {
+    const user = state.studyUsers.find(u => u.id === req.params.id)
+    if (!user) { res.status(404).json({ message: 'User not found.' }); return }
+
+    const tier = req.body?.tier
+    if (tier !== 't1' && tier !== 't2' && tier !== 't3') {
+      res.status(400).json({ message: 'tier must be t1, t2, or t3.' }); return
+    }
+
+    const studies = Array.isArray(state.cachedSiteContent?.studies) ? state.cachedSiteContent.studies : []
+    const enrolledStudySlugs = Array.isArray(user.enrolledStudySlugs) ? user.enrolledStudySlugs : []
+    const enrolledStudies = enrolledStudySlugs
+      .map(slug => studies.find(s => normalizeStudySlug(s?.slug) === slug))
+      .filter(Boolean)
+
+    if (enrolledStudies.length === 0) { res.status(400).json({ message: 'User has no enrolled studies.' }); return }
+
+    const firstStudy = enrolledStudies[0]
+    const studyTitle = enrolledStudies.length === 1 ? firstStudy.title : null
+    const canonical = state.cachedSiteContent?.seo?.canonicalUrl || 'https://versebyversewithnate.us/'
+    const base = canonical.endsWith('/') ? canonical.slice(0, -1) : canonical
+    const studyUrl = enrolledStudies.length === 1 ? `${base}/study/${firstStudy.slug}` : `${base}/study`
+    const unsubUrl = makeUnsubUrl(user.id)
+
+    try {
+      await sendStudyReengagementEmail(user.username, user.displayName || user.username, studyTitle, studyUrl, tier, unsubUrl)
+      res.json({ ok: true })
+    } catch (err) {
+      console.error(`[admin] manual reengagement send failed for ${user.username}:`, err)
+      res.status(500).json({ message: 'Failed to send email.' })
+    }
+  })
+
   app.patch('/api/admin/study-users/:id', requireAdminAuth, (req, res) => {
     const user = state.studyUsers.find(u => u.id === req.params.id)
     if (!user) { res.status(404).json({ message: 'User not found.' }); return }

server/routes/study-account.js

@@ -218,6 +218,8 @@ export function register(app) {
         displayName: user.displayName ?? '',
         subscribeNewsletter: user.subscribeNewsletter !== false,
         studyRemindersEnabled: user.studyRemindersEnabled === true,
+        reminderFrequency: user.reminderFrequency ?? 'immediate',
+        remindersPausedUntil: user.remindersPausedUntil ?? null,
         avatarUrl: getStudyAvatarUrl(user),
       },
       stats: {
@@ -303,6 +305,20 @@ export function register(app) {
     const studyRemindersEnabled = req.body?.studyRemindersEnabled === true
     user.subscribeNewsletter = subscribeNewsletter
     user.studyRemindersEnabled = studyRemindersEnabled
+
+    const reminderFrequency = req.body?.reminderFrequency
+    if (reminderFrequency === 'weekly' || reminderFrequency === 'immediate') {
+      user.reminderFrequency = reminderFrequency
+    }
+
+    const rawPaused = req.body?.remindersPausedUntil
+    if (rawPaused === null || rawPaused === '') {
+      user.remindersPausedUntil = null
+    } else if (typeof rawPaused === 'string') {
+      const parsed = new Date(rawPaused)
+      user.remindersPausedUntil = !isNaN(parsed.getTime()) && parsed.getTime() > Date.now() ? parsed.toISOString() : null
+    }
+
     user.updatedAt = new Date().toISOString()
     queueStudyUsersWrite()
 
@@ -310,7 +326,13 @@ export function register(app) {
       syncContactToResend(user.displayName || user.username, user.username).catch(err => console.error('[study-account] resend sync error:', err))
     }
 
-    res.json({ ok: true, subscribeNewsletter: user.subscribeNewsletter, studyRemindersEnabled: user.studyRemindersEnabled === true })
+    res.json({
+      ok: true,
+      subscribeNewsletter: user.subscribeNewsletter,
+      studyRemindersEnabled: user.studyRemindersEnabled === true,
+      reminderFrequency: user.reminderFrequency ?? 'immediate',
+      remindersPausedUntil: user.remindersPausedUntil ?? null,
+    })
   })
 
   app.post('/api/study-account/request-email-change', studyAuthRateLimiter, requireStudyAuth, async (req, res) => {

server/routes/study-certificate.js

@@ -4,6 +4,8 @@ import { requireAdminAuth } from '../auth.js'
 import { requireStudyAuth, normalizeStudySlug, isStudyUserEnrolled, getStudyTitleBySlug } from '../study-helpers.js'
 import { state } from '../state.js'
 import { loadUserProgress, queueStudyCertificatesWrite } from '../data.js'
+import { sendStudyCertificateEmail, getCanonicalBaseUrl } from '../email.js'
+import { buildAbsoluteUrl } from '../helpers.js'
 
 const publicCertRateLimiter = rateLimit({
   windowMs: 15 * 60 * 1000,
@@ -95,6 +97,9 @@ export function register(app) {
       }
       state.studyCertificates.push(cert)
       queueStudyCertificatesWrite()
+      const certUrl = buildAbsoluteUrl(getCanonicalBaseUrl(), `/study/certificate/${cert.token}`)
+      sendStudyCertificateEmail(user.username, user.displayName || user.username, cert.studyTitle, certUrl)
+        .catch(err => console.error('[study-certificate] email exception:', err))
     }
 
     res.json({ ok: true, token: cert.token, issuedAt: cert.issuedAt })

server/routes/study-data.js

@@ -171,6 +171,7 @@ export function register(app) {
 
     const progress = await loadUserProgress(user.id)
     const completedSectionIds = progress.byStudy[studySlug]?.completedSectionIds ?? []
+    const bookmarkedSectionIds = progress.byStudy[studySlug]?.bookmarkedSectionIds ?? []
 
     // Record first visit timestamp on the user record (additive, never overwrite)
     if (!user.firstVisitAt) {
@@ -178,7 +179,7 @@ export function register(app) {
       queueStudyUsersWrite()
     }
 
-    res.json({ studySlug, completedSectionIds })
+    res.json({ studySlug, completedSectionIds, bookmarkedSectionIds })
   })
 
   app.post('/api/study-progress/:studySlug/:sectionId', requireStudyAuth, async (req, res) => {
@@ -301,6 +302,45 @@ export function register(app) {
     res.json({ ok: true, studySlug, sectionId, answers })
   })
 
+  // ── Bookmarks ─────────────────────────────────────────────────────────────
+
+  app.post('/api/study-progress/:studySlug/:sectionId/bookmark', requireStudyAuth, async (req, res) => {
+    const user = req.studyUser
+    const studySlug = normalizeStudySlug(req.params.studySlug)
+    const sectionId = normalizeLessonSectionId(req.params.sectionId)
+    if (!studySlug || !sectionId) { res.status(400).json({ message: 'Invalid study slug or section id.' }); return }
+    if (!isStudyUserEnrolled(user, studySlug)) { res.status(403).json({ message: 'Please enroll in this study to bookmark lessons.' }); return }
+
+    const progress = await loadUserProgress(user.id)
+    const studyProgress = progress.byStudy[studySlug] ?? { completedSectionIds: [], bookmarkedSectionIds: [] }
+    const bookmarkedSectionIds = Array.isArray(studyProgress.bookmarkedSectionIds) ? studyProgress.bookmarkedSectionIds : []
+    if (!bookmarkedSectionIds.includes(sectionId)) {
+      studyProgress.bookmarkedSectionIds = [...bookmarkedSectionIds, sectionId]
+    }
+    progress.byStudy[studySlug] = studyProgress
+    progress.updatedAt = new Date().toISOString()
+    state.studyProgressCache.set(user.id, progress)
+    queueUserProgressWrite(user.id)
+    res.json({ ok: true, studySlug, bookmarkedSectionIds: studyProgress.bookmarkedSectionIds })
+  })
+
+  app.delete('/api/study-progress/:studySlug/:sectionId/bookmark', requireStudyAuth, async (req, res) => {
+    const user = req.studyUser
+    const studySlug = normalizeStudySlug(req.params.studySlug)
+    const sectionId = normalizeLessonSectionId(req.params.sectionId)
+    if (!studySlug || !sectionId) { res.status(400).json({ message: 'Invalid study slug or section id.' }); return }
+    if (!isStudyUserEnrolled(user, studySlug)) { res.status(403).json({ message: 'Not enrolled.' }); return }
+
+    const progress = await loadUserProgress(user.id)
+    const studyProgress = progress.byStudy[studySlug] ?? { completedSectionIds: [], bookmarkedSectionIds: [] }
+    studyProgress.bookmarkedSectionIds = (studyProgress.bookmarkedSectionIds ?? []).filter(id => id !== sectionId)
+    progress.byStudy[studySlug] = studyProgress
+    progress.updatedAt = new Date().toISOString()
+    state.studyProgressCache.set(user.id, progress)
+    queueUserProgressWrite(user.id)
+    res.json({ ok: true, studySlug, bookmarkedSectionIds: studyProgress.bookmarkedSectionIds })
+  })
+
   // ── Community ─────────────────────────────────────────────────────────────
 
   app.get('/api/study-community', requireStudyAuth, async (req, res) => {

server/study-helpers.js

@@ -622,6 +622,9 @@ export async function scheduleStudyReminders(sendStudyReminderEmail) {
 
   for (const user of state.studyUsers) {
     if (user.studyRemindersEnabled !== true) continue
+    if (user.reminderFrequency === 'weekly') continue
+    const pausedUntil = user.remindersPausedUntil ? new Date(user.remindersPausedUntil) : null
+    if (pausedUntil && !isNaN(pausedUntil.getTime()) && pausedUntil > now) continue
     const email = user.username
     const displayName = user.displayName || email
     const enrolledStudySlugs = Array.isArray(user.enrolledStudySlugs) ? user.enrolledStudySlugs : []
@@ -677,7 +680,7 @@ function getReengagementTiers() {
   return days.slice(0, 3).map((d, i) => ({ key: `t${i + 1}`, days: d }))
 }
 
-function makeUnsubUrl(userId) {
+export function makeUnsubUrl(userId) {
   const secret = process.env.RESEND_WEBHOOK_TOKEN ?? 'siteforge'
   const token = createHmac('sha256', secret).update(userId).digest('hex')
   const canonical = state.cachedSiteContent?.seo?.canonicalUrl || 'https://versebyversewithnate.us/'
@@ -694,6 +697,8 @@ export async function scheduleReengagementEmails(sendStudyReengagementEmail) {
   for (const user of state.studyUsers) {
     if (user.studyRemindersEnabled !== true) continue
     if (!user.lastLoginAt) continue
+    const pausedUntil = user.remindersPausedUntil ? new Date(user.remindersPausedUntil) : null
+    if (pausedUntil && !isNaN(pausedUntil.getTime()) && pausedUntil > now) continue
     const lastLogin = new Date(user.lastLoginAt)
     if (isNaN(lastLogin.getTime())) continue
     const daysSinceLogin = (nowMs - lastLogin.getTime()) / (1000 * 60 * 60 * 24)
@@ -733,3 +738,77 @@ export async function scheduleReengagementEmails(sendStudyReengagementEmail) {
     }
   }
 }
+
+// ── Weekly digest scheduler ───────────────────────────────────────────────
+
+export async function scheduleWeeklyDigestEmails(sendStudyWeeklyDigestEmail) {
+  if (!state.cachedSiteContent) return
+  const now = new Date()
+  const nowMs = now.getTime()
+  const ONE_WEEK_MS = 7 * 24 * 60 * 60 * 1000
+
+  for (const user of state.studyUsers) {
+    if (user.reminderFrequency !== 'weekly') continue
+    if (user.studyRemindersEnabled !== true) continue
+
+    const pausedUntil = user.remindersPausedUntil ? new Date(user.remindersPausedUntil) : null
+    if (pausedUntil && !isNaN(pausedUntil.getTime()) && pausedUntil > now) continue
+
+    const lastDigestMs = user.weeklyDigestSentAt ? new Date(user.weeklyDigestSentAt).getTime() : 0
+    if (nowMs - lastDigestMs < ONE_WEEK_MS) continue
+
+    const enrolledStudySlugs = Array.isArray(user.enrolledStudySlugs) ? user.enrolledStudySlugs : []
+    if (enrolledStudySlugs.length === 0) continue
+
+    const userSent = state.studyReminders.users[user.id] ?? {}
+    const lessons = []
+    const newlySentByStudy = {}
+
+    for (const studySlug of enrolledStudySlugs) {
+      const study = Array.isArray(state.cachedSiteContent.studies)
+        ? state.cachedSiteContent.studies.find(item => normalizeStudySlug(item?.slug) === studySlug)
+        : undefined
+      if (!study) continue
+
+      for (const section of study.sections ?? []) {
+        const releaseTime = getSectionReleaseTime(section)
+        if (!Number.isFinite(releaseTime) || releaseTime > nowMs) continue
+        const sentForStudy = Array.isArray(userSent[studySlug]) ? userSent[studySlug] : []
+        if (sentForStudy.includes(section.id)) continue
+
+        const canonical = state.cachedSiteContent?.seo?.canonicalUrl || 'https://versebyversewithnate.us/'
+        const base = canonical.endsWith('/') ? canonical.slice(0, -1) : canonical
+        lessons.push({
+          sectionId: section.id,
+          studySlug,
+          sectionTitle: section.title ?? section.id,
+          sectionReference: section.reference ?? '',
+          studyTitle: study.title ?? studySlug,
+          sectionUrl: `${base}/study/${study.slug}/${section.id}`,
+        })
+        if (!newlySentByStudy[studySlug]) newlySentByStudy[studySlug] = []
+        newlySentByStudy[studySlug].push(section.id)
+      }
+    }
+
+    if (lessons.length === 0) continue
+
+    const unsubUrl = makeUnsubUrl(user.id)
+    try {
+      await sendStudyWeeklyDigestEmail(user.username, user.displayName || user.username, lessons, unsubUrl)
+    } catch (err) {
+      console.error(`[study-digest] failed to send digest to ${user.username}:`, err)
+      continue
+    }
+
+    for (const [studySlug, sectionIds] of Object.entries(newlySentByStudy)) {
+      const sentForStudy = Array.isArray(userSent[studySlug]) ? userSent[studySlug] : []
+      userSent[studySlug] = [...new Set([...sentForStudy, ...sectionIds])]
+    }
+    state.studyReminders.users[user.id] = userSent
+    queueStudyRemindersWrite()
+
+    user.weeklyDigestSentAt = now.toISOString()
+    queueStudyUsersWrite()
+  }
+}