Merge pull request 'Stop the availability form failing in silence' (#137) from fix/availability-silent-failures into main

Reviewed-on: #137

CHANGELOG.md

@@ -11,6 +11,13 @@ When a `v*` tag is pushed, `.gitea/workflows/release.yml` publishes the matching
 the plugin to the next patch version and adds a fresh section here for it. Record
 each change under the current top section as you work.
 
+## [1.2.4]
+
+### Fixed
+- **Adding availability no longer fails in silence.** Entering a window shorter than the chosen lesson length — 5:30–6:00 PM with the lesson length left on its default of 60 minutes, say — saved nothing and said nothing: the page just reloaded, whether the window was one-off or set to repeat for 41 weeks. The **Lesson length** menu now offers only the lengths that actually fit the window you have entered, and the form refuses to submit when none of them do. Every other way the form could quietly do nothing now explains itself too — an unreadable date, an end time before the start, a window running past midnight into the next day — and a successful save says how many bookable slots it created. Deleting says whether the slot went, and tells you when one is refused because it is already booked. Availability added through the API is checked against exactly the same rules, which it previously enforced slightly differently.
+- A student's **upcoming lessons no longer pile on top of each other**. On the booking page, the lesson name, its date and time, the status badge and the **Cancel** button could render over one another instead of sitting in a tidy row — worst with a long lesson-type name, and on narrow screens, where the row had no phone layout at all. The panel now keeps its shape whatever the theme around it does, long names wrap instead of shoving the Cancel button out of the row, and on a phone the lesson details stack above the buttons.
+- The registration page **no longer dead-ends a visitor who is already signed in**. It used to greet them with "You already have an account and are logged in." and nothing else, leaving them to find their own way to the studio. They now get a link onward to the page chosen under the block's **After registration** panel, and the link names it — "Continue to Book a Lesson" rather than the vaguer wording an invited student used to see. With no page chosen, the message appears on its own as before, because sending someone who is already signed in to the sign-in screen helps nobody.
+
 ## [1.2.3]
 
 ### Changed
@@ -18,8 +25,12 @@ each change under the current top section as you work.
 
 ### Added
 - Every price a student sees now says **when** it is due. Lesson types in the booking form read `50.00 CAD at booking`, and group-class cards read `120.00 CAD up front`, `40.00 CAD weekly` or `40.00 CAD monthly` — the offering's billing mode, in the student's words. A monthly **private lesson** is quoted per lesson (`50.00 CAD per lesson monthly`), since its monthly charge covers every lesson booked that month; a monthly group class is quoted as the monthly figure it is. A free offering still just reads **Free**.
+- The **Policies** admin page can now **show you what is actually in a version**. Every row in the versions table has a **View** button that opens that version's text below the table, rendered exactly as students see it at booking and signup, whether the version is the published one, an old archived one, or a draft nobody has seen yet. The text is editable straight from the viewer, and what happens when you save depends on the version: a draft is simply updated in place, while editing a **published or archived version saves your text as a new draft version** and leaves the original exactly as students accepted it. The new draft then opens in the viewer ready to publish. Nothing a student has agreed to is ever rewritten.
 - Booking a lesson and enrolling in a class now take a **second confirmation that the student agrees to pay**. Above the Confirm button the form restates the price with its cadence, spells out how it is collected ("Charged on the 1st of each month, for that month's lessons"), adds the studio's HST so the figure matches the total actually billed, and requires a tick on "I agree to pay 56.50 CAD at booking." before it will submit — separate from, and in addition to, the studio policies the student accepts above it. Reserving a time weekly quotes the per-lesson fee and the most it can add up to ("up to 12 lessons, 678.00 CAD in total"), since a week another student takes first is simply not booked. Free offerings have nothing to agree to and show no price block.
 
+### Fixed
+- Policies are **readable where students have to accept them**. A policy typed as plain paragraphs — the normal way to write one, with no HTML — was being dropped into the booking, enrolment, and signup forms unformatted, collapsing the whole document into a single squashed line with a horizontal scrollbar and words piling on top of each other. Policy text is now formatted the same way WordPress formats post content, so blank lines become real paragraphs, and the acceptance box is styled as a proper bounded reading panel: long policies scroll vertically instead of running off the side of the page, long pasted links wrap rather than forcing the page sideways, and the "I have read and agree" tick stays in view. Policies written with HTML are unaffected. The studio registration page was also missing the plugin's stylesheet entirely, which is why the problem was at its worst there.
+
 ## [1.2.2]
 
 ### Added

assets/css/frontend.css

@@ -34,47 +34,72 @@
     margin-top: 8px;
 }
 
-.us-my-lessons {
+/*
+ * The upcoming-lessons panel. Every rule here is scoped under #us-booking-app —
+ * the same id-level specificity .us-slot above uses — because these rows sit in
+ * whatever layout the theme provides and carry more content than a calendar
+ * cell. Bare class selectors lost to theme rules on div/span/strong, which
+ * collapsed the flex layout and piled the details on top of the actions.
+ */
+#us-booking-app .us-my-lessons {
     margin-bottom: 24px;
 }
 
-.us-my-lesson {
+#us-booking-app .us-my-lesson {
+    box-sizing: border-box;
+    max-width: 100%;
     border: 1px solid #ddd;
     border-radius: 4px;
     padding: 12px 16px;
     margin-bottom: 8px;
     display: flex;
+    flex-wrap: wrap;
     justify-content: space-between;
     align-items: center;
-    gap: 12px;
+    gap: 8px 12px;
 }
 
-.us-my-lesson-info {
+/*
+ * `min-width: 0` lets the title column shrink below its content width — without
+ * it a long offering title cannot compress and shoves the status pill and
+ * Cancel button out of the row. The flex-basis keeps the details and the
+ * actions on one line while there is room, and wraps them once there is not.
+ */
+#us-booking-app .us-my-lesson-info {
     display: flex;
     flex-direction: column;
     gap: 2px;
+    flex: 1 1 14em;
+    min-width: 0;
 }
 
-.us-my-lesson-title {
+#us-booking-app .us-my-lesson-title,
+#us-booking-app .us-my-lesson-when {
+    overflow-wrap: break-word;
+    word-break: break-word;
+}
+
+#us-booking-app .us-my-lesson-title {
     font-size: 1.05em;
 }
 
-.us-my-lesson-duration {
+#us-booking-app .us-my-lesson-duration {
     font-weight: normal;
     color: #666;
 }
 
-.us-my-lesson-when {
+#us-booking-app .us-my-lesson-when {
     color: #555;
 }
 
-.us-my-lesson-actions {
+#us-booking-app .us-my-lesson-actions {
     display: flex;
-    gap: 12px;
+    flex-wrap: wrap;
+    gap: 8px 12px;
     align-items: center;
 }
 
-.us-show-all-lessons {
+#us-booking-app .us-show-all-lessons {
     background: transparent;
     border: 1px solid #ccc;
     border-radius: 4px;
@@ -82,11 +107,11 @@
     cursor: pointer;
 }
 
-.us-show-all-lessons:hover {
+#us-booking-app .us-show-all-lessons:hover {
     border-color: #888;
 }
 
-.us-cancel-lesson {
+#us-booking-app .us-cancel-lesson {
     background: transparent;
     border: 1px solid #ccc;
     border-radius: 4px;
@@ -95,24 +120,26 @@
     color: #c00;
 }
 
-.us-cancel-lesson:hover {
+#us-booking-app .us-cancel-lesson:hover {
     border-color: #c00;
 }
 
-.us-lesson-status {
+#us-booking-app .us-lesson-status {
+    display: inline-block;
     font-size: 0.85em;
     font-weight: 600;
     padding: 2px 10px;
     border-radius: 10px;
     background: #eee;
+    white-space: nowrap;
 }
 
-.us-lesson-status-confirmed {
+#us-booking-app .us-lesson-status-confirmed {
     background: #e2f5e5;
     color: #1a7d2e;
 }
 
-.us-lesson-status-pending {
+#us-booking-app .us-lesson-status-pending {
     background: #fdf3d7;
     color: #8a6d1a;
 }
@@ -282,6 +309,61 @@
     font-weight: 600;
 }
 
+/* Policy acceptance — booking, enrolment, and signup all render this markup. */
+.us-policy {
+    margin: 16px 0;
+}
+
+.us-policy h4 {
+    margin: 0 0 6px;
+}
+
+/*
+ * The body is admin-authored HTML sitting inside whatever layout the theme
+ * provides, so it gets an explicit reading box rather than inheriting one.
+ * `overflow-wrap` breaks pasted URLs instead of letting one long token force
+ * the horizontal scrollbar, and the bounded height keeps a long policy from
+ * pushing the accept checkbox off the screen.
+ */
+.us-policy-body {
+    box-sizing: border-box;
+    max-width: 100%;
+    max-height: 260px;
+    overflow-y: auto;
+    overflow-x: hidden;
+    padding: 12px 14px;
+    margin-bottom: 8px;
+    border: 1px solid #ddd;
+    border-radius: 4px;
+    background: #fafafa;
+    white-space: normal;
+    overflow-wrap: break-word;
+    word-break: break-word;
+    line-height: 1.5;
+    text-align: left;
+}
+
+.us-policy-body p,
+.us-policy-body ul,
+.us-policy-body ol {
+    margin: 0 0 0.75em;
+    max-width: 100%;
+}
+
+.us-policy-body ul,
+.us-policy-body ol {
+    padding-left: 1.5em;
+}
+
+.us-policy-body > :last-child {
+    margin-bottom: 0;
+}
+
+.us-policy-accept,
+.us-policies input[type="checkbox"] {
+    margin-right: 6px;
+}
+
 @media (max-width: 640px) {
     .us-week-grid {
         grid-template-columns: 1fr;
@@ -290,6 +372,20 @@
     .us-week-day {
         min-height: 0;
     }
+
+    /*
+     * A lesson row carries a title, a date/time, a status pill and a button —
+     * more than fits one narrow line, so stack the details above the actions
+     * rather than letting them wrap into each other.
+     */
+    #us-booking-app .us-my-lesson {
+        flex-direction: column;
+        align-items: stretch;
+    }
+
+    #us-booking-app .us-my-lesson-info {
+        flex: 0 0 auto;
+    }
 }
 
 /* Shown only in block-editor previews (see BlockPreview). */

assets/js/availability-admin.js

@@ -0,0 +1,98 @@
+/**
+ * Availability form: keep the lesson-length choices honest.
+ *
+ * A window is stored as consecutive lesson-length slots, so one shorter than the
+ * chosen lesson length holds no slots at all and saves nothing. Picking 5:30–6:00
+ * PM while the length select sat on its default of 60 minutes used to do exactly
+ * that, silently. The server now rejects it with a message; this narrows the
+ * choices first so the mistake is hard to make.
+ *
+ * This is a convenience only — AvailabilityController and the REST endpoint both
+ * validate the same window server-side regardless of what happens here.
+ */
+(function () {
+    'use strict';
+
+    const form = document.getElementById('usc-add-availability');
+    if (!form) return;
+
+    const startEl    = document.getElementById('start_dt');
+    const endEl      = document.getElementById('end_dt');
+    const durationEl = document.getElementById('duration_minutes');
+    const warningEl  = document.getElementById('usc-duration-warning');
+    const submitEl   = form.querySelector('input[type="submit"], button[type="submit"]');
+
+    if (!startEl || !endEl || !durationEl) return;
+
+    /**
+     * Minutes between the two datetime-local inputs, or 0 when the pair is not a
+     * usable window yet — empty, unparseable, backwards, or spanning two days
+     * (which the server rejects on its own terms, with its own message).
+     */
+    function windowMinutes() {
+        const start = new Date(startEl.value);
+        const end   = new Date(endEl.value);
+
+        if (!startEl.value || !endEl.value || isNaN(start) || isNaN(end)) return 0;
+        if (end <= start) return 0;
+        if (startEl.value.slice(0, 10) !== endEl.value.slice(0, 10)) return 0;
+
+        return Math.round((end - start) / 60000);
+    }
+
+    function refresh() {
+        const minutes = windowMinutes();
+        const options = Array.from(durationEl.options);
+
+        // No usable window yet: leave every choice alone rather than fighting
+        // someone part-way through typing a date.
+        if (minutes === 0) {
+            options.forEach((option) => {
+                option.hidden   = false;
+                option.disabled = false;
+            });
+            setBlocked(false);
+            return;
+        }
+
+        let fits = [];
+
+        options.forEach((option) => {
+            const tooLong = Number(option.value) > minutes;
+
+            option.hidden   = tooLong;
+            option.disabled = tooLong;
+
+            if (!tooLong) fits.push(option);
+        });
+
+        if (fits.length === 0) {
+            // Nothing bookable fits, so the form cannot produce a single slot.
+            setBlocked(true);
+            return;
+        }
+
+        setBlocked(false);
+
+        // The selection may have just been hidden — fall back to the longest
+        // length that still fits, which is what the instructor most likely wants.
+        if (durationEl.selectedOptions[0] && durationEl.selectedOptions[0].disabled) {
+            durationEl.value = fits.reduce(
+                (longest, option) => (Number(option.value) > Number(longest.value) ? option : longest),
+                fits[0]
+            ).value;
+        }
+    }
+
+    function setBlocked(blocked) {
+        if (warningEl) warningEl.hidden = !blocked;
+        if (submitEl) submitEl.disabled = blocked;
+    }
+
+    startEl.addEventListener('change', refresh);
+    startEl.addEventListener('input', refresh);
+    endEl.addEventListener('change', refresh);
+    endEl.addEventListener('input', refresh);
+
+    refresh();
+}());

assets/js/booking.js

@@ -582,16 +582,19 @@
     function lessonRowHtml(l) {
         const title    = l.offering_title ? escHtml(String(l.offering_title)) : 'Lesson';
         const duration = l.duration_minutes ? ` <span class="us-my-lesson-duration">(${escHtml(String(l.duration_minutes))} min)</span>` : '';
+        // The two columns are divs, not spans: as spans the layout only held up
+        // while the stylesheet's display:flex won, and a theme rule on span
+        // collapsed the row onto itself.
         return `
             <div class="us-my-lesson">
-                <span class="us-my-lesson-info">
+                <div class="us-my-lesson-info">
                     <strong class="us-my-lesson-title">${title}${duration}</strong>
                     <span class="us-my-lesson-when">${escHtml(dayLabel(dayKey(l.start_dt)))} · ${escHtml(timeOf(l.start_dt))}–${escHtml(timeOf(l.end_dt))}</span>
-                </span>
+                </div>
-                <span class="us-my-lesson-actions">
+                <div class="us-my-lesson-actions">
                     <span class="us-lesson-status us-lesson-status-${escHtml(String(l.status))}">${escHtml(lessonStatusLabel(String(l.status)))}</span>
                     <button type="button" class="us-cancel-lesson" data-lesson-id="${l.id}">Cancel</button>
-                </span>
+                </div>
             </div>`;
     }
 

docs/features/account-registration.md

@@ -132,7 +132,7 @@ recorded in `us_policy_acceptances` with `registration_type = account` and
 The block's **After registration** panel picks the page a student continues to once
 registration finishes, and whether they get there by hand or automatically.
 
-- **Sign-in page** (`loginPageId` / `login_page_id`) — the target of the "Sign in to your account" link shown after email confirmation (`?us_confirmed=1|ready`, falling back to the WordPress login screen) and of the "Continue to your account" link an invited student sees on the spot (`?us_registered=invite`; no link at all with no page chosen, since an already-signed-in student has no use for the login screen).
+- **Sign-in page** (`loginPageId` / `login_page_id`) — the target of the "Sign in to your account" link shown after email confirmation (`?us_confirmed=1|ready`, falling back to the WordPress login screen) and of the **"Continue to _<page title>_"** link every **logged-in** visitor gets (`RegistrationPage::continueLink()`): an invited student who just finished signing up (`?us_registered=invite`), and anyone who simply arrives at the registration page already signed in. The link names the chosen page (via `get_the_title()`) so the visitor knows where it goes; an untitled page falls back to "Continue to your account" rather than reading "Continue to ". Neither gets the WordPress-login-screen fallback — with no page chosen there is no link at all, since sending someone already signed in to the login screen is the same dead end with extra steps.
 - **Redirect automatically** (`autoRedirect`, block only) — sends the student to that page instead of showing the link, via `BlockRegistrar::maybeAutoRedirect()` on `template_redirect`. It fires only on those two finished states (`RegistrationPage::isRegistrationComplete()`), so the "check your email" step, a validation error, and an `expired` confirmation link are always shown rather than redirected past. With no page chosen nothing happens — there is deliberately no login-screen fallback for the redirect. See `editor-blocks.md`.
 
 ## Token Redirect

docs/features/availability-management.md

@@ -25,8 +25,9 @@ A slot's `duration_minutes` is matched against the offering a student picks: a
 `AvailabilitySlot::splitByDuration()` chunks a submitted window into consecutive
 `duration_minutes` slots; `AvailabilityRepository::createFromWindow()` persists
 one row per chunk. A trailing remainder shorter than the lesson length is
-dropped. Windows must start and end on the same day and fit at least one lesson
+dropped. Windows must start and end on the same day and fit at least one lesson;
-(REST responds `400 invalid_window` otherwise; the admin form is a no-op).
+both the REST endpoint and the admin form reject one that does not, with a
+message saying so (see **REST API** below).
 `AvailabilityRepository::splitOversizedWindows()` is a data migration (run by
 `Installer` on activation or version change) that rewrites pre-split rows.
 
@@ -44,6 +45,27 @@ Instructors access **My Availability** in wp-admin (`?page=us-availability`).
 - Bulk delete: the list view has a checkbox per unbooked slot (with a select-all header checkbox) and a **Delete selected** button (`usc_action=bulk_delete`, `slot_ids[]`); each id is ownership-checked, and booked slots are refused at the repository level
 - Current slots can be shown as a **weekly calendar** (the default, navigated with `usc_week=Y-m-d`) or a **list** (`usc_view=list`); the grid honours the site's `start_of_week` option via `Availability\WeekCalendar`
 
+### Feedback
+Every submitted action reports its outcome as a wp-admin notice — a success
+notice naming the number of slots created or deleted, or an error explaining the
+refusal. `AvailabilityController::handleFormAction()` returns a
+`[$notice, $error]` pair that `templates/admin/availability.php` renders.
+
+This matters because the form used to fail **silently**: a window shorter than
+the chosen lesson length splits into no slots, so nothing was written, nothing
+was said, and the page simply reloaded. Submitting 5:30–6:00 PM with the length
+select on its 60-minute default was the reported case. Invalid datetimes, an end
+before the start, a window spanning two days, and an offering belonging to
+another instructor were all silent in the same way.
+
+### Lesson-length choices
+`assets/js/availability-admin.js` (enqueued by `AdminMenu::enqueueAssets()` on
+this screen only) hides any lesson length longer than the entered window, falls
+back to the longest one that still fits when the current pick is hidden, and
+disables the submit button when nothing fits. It is a convenience, not a
+guarantee — the server validates the same window regardless. The choices come
+from `AvailabilitySlot::DURATION_CHOICES`.
+
 ## Public Calendar
 The front-end booking shortcode renders open slots from `GET /availability`
 either as an agenda-style list grouped by day or as a **weekly calendar** with
@@ -62,12 +84,29 @@ with the **Show Only** lesson-type filter — see `lesson-booking.md`.
 `GET` supports query params: `instructor_id`, `offering_id`, `duration_minutes`, `from` (datetime), `to` (datetime).
 Slots whose start has already passed are never returned.
 
-`POST` validates `start_dt`/`end_dt` (admin form and REST alike) via
+`POST` runs every submitted window — admin form and REST alike — through
-`AvailabilitySlot::normalizeDateTime()`: the canonical `Y-m-d H:i[:s]` and HTML
+`Availability\WindowValidator`, which returns either the window ready to persist
-`datetime-local` (`Y-m-d\TH:i[:s]`) forms are normalised to `Y-m-d H:i:s`;
+or a `WP_Error`. The REST endpoint returns that error directly (its `status`
-anything else — or an end not after the start — is rejected (REST responds
+data makes it a 400); the admin screen shows `get_error_message()` in a notice.
-`400 invalid_datetime`; the admin form is a no-op). A valid window is stored as
+Sharing one validator is deliberate: the two paths previously checked the same
+rules separately, and the admin copy was both laxer (no offering-ownership
+check) and mute (a bare `return` on every rejection).
+
+| Rejection | Code |
+|---|---|
+| Start or end not a real datetime | `invalid_datetime` |
+| End at or before the start | `invalid_datetime` |
+| Window spans two days | `invalid_window` |
+| Window shorter than the lesson length (so it holds no slots) | `invalid_window` |
+| Offering missing, or owned by another instructor | `invalid_offering` |
+
+`start_dt`/`end_dt` are normalised by `AvailabilitySlot::normalizeDateTime()`:
+the canonical `Y-m-d H:i[:s]` and HTML `datetime-local` (`Y-m-d\TH:i[:s]`) forms
+become `Y-m-d H:i:s`; anything else is rejected. A valid window is stored as
 lesson-length slots and `201` returns `{ "ids": [...] }` for every row created.
+`weeks` is clamped to `AvailabilitySlot::MAX_WEEKLY_OCCURRENCES` in the
+repository, so the form's `max` cannot be bypassed by posting directly. A write
+that fails entirely returns `500 not_saved` rather than a `201` listing no ids.
 
 Times are displayed in 12-hour AM/PM form in the booking calendar and wp-admin
 lists.
@@ -78,6 +117,8 @@ lists.
 - Week bucketing: `Unsupervised\Schedular\Availability\WeekCalendar`
 - Admin controller: `Unsupervised\Schedular\Availability\AvailabilityController`
 - REST endpoint: `Unsupervised\Schedular\Availability\AvailabilityEndpoint`
+- Shared window validation: `Unsupervised\Schedular\Availability\WindowValidator`
+- Admin form script: `assets/js/availability-admin.js`, enqueued by `AdminMenu::enqueueAssets()`
 
 ## Tests
 - `tests/Unit/Availability/AvailabilityControllerTest.php`
@@ -85,3 +126,4 @@ lists.
 - `tests/Unit/Availability/AvailabilitySlotTest.php`
 - `tests/Unit/Availability/AvailabilityEndpointTest.php`
 - `tests/Unit/Availability/WeekCalendarTest.php`
+- `tests/Unit/Availability/WindowValidatorTest.php`

docs/features/lesson-booking.md

@@ -154,6 +154,7 @@ instructor may only open their own lessons; the studio **Scheduler** may open an
 - Admin lesson detail presenter: `Unsupervised\Schedular\Booking\LessonDetail` (per-lesson intake answers + policy acceptances), template `templates/admin/lesson-detail.php`
 - REST endpoint: `Unsupervised\Schedular\Booking\BookingEndpoint`
 - Frontend: `Unsupervised\Schedular\Booking\BookingPage`, `Unsupervised\Schedular\Auth\LoginPage`
+- Upcoming-lessons panel: rendered client-side into `#us-my-lessons` by `assets/js/booking.js` (`lessonRowHtml`/`renderMyLessons`), mirrored for the editor by `BlockPreview::upcomingLessons()` — keep the two markup shapes in step.
 
 > **Payment seam:** a priced booking is created with `status = pending` and its
 > payment linked via `payment_id`; the lesson is confirmed when the payment is
@@ -161,6 +162,14 @@ instructor may only open their own lessons; the studio **Scheduler** may open an
 > Unpriced bookings skip the seam entirely and are confirmed at creation.
 > `GET /policies?scope=booking` returns just the booking-gate policies the form
 > must collect.
+>
+> **Frontend CSS scoping:** every rule for the booking page's own markup is
+> written under `#us-booking-app` (`assets/css/frontend.css`). These panels sit
+> inside whatever layout the active theme provides, and bare class selectors lose
+> to theme rules on `div`/`span`/`strong` — which flattens the flex layout and
+> renders the lesson details on top of the actions. The row's two columns are
+> `div`s for the same reason: the layout must not depend on overriding the
+> inline default. New booking-page rules should follow both conventions.
 
 ## Tests
 - `tests/Unit/Booking/BookingRepositoryTest.php`

docs/features/policies.md

@@ -40,14 +40,22 @@ The studio admin drafts, versions, and publishes policies (e.g. cancellation, pa
 
 ## Versioning & Acceptance Rules
 - Editing a published policy creates a new `draft` version; the old version stays `published` until the draft is published.
+- Editing a `draft` version rewrites it in place — nobody has accepted it yet, so there is nothing to preserve and no new version is created. `PATCH /policies/{id}/versions/{vid}` allows only this case; the admin page also accepts an edit to a `published` or `archived` version and branches a new draft from it.
 - Publishing a draft sets it `published`, stamps `published_at`, archives the prior version, and points `us_policies.current_version_id` at it.
 - The registration gate requires acceptance of the `current_version_id` of every policy. Because acceptance is tied to `policy_version_id`, a newly published version is unaccepted and must be re-accepted at the student's next booking.
 
 ## Admin Interface
 **Policies** in wp-admin (`manage_policies`, studio admin only):
-- Create a policy; draft and edit version bodies
+- Create a policy; draft version bodies
+- View the content of any version (`?page=us-policies&policy_id={id}&version_id={vid}`), whatever its status
+- Edit from the viewer: a draft is saved in place; editing a published or archived version instead saves the text as a **new draft version** (the viewer follows to it), so text students have already accepted is never rewritten
 - Publish a draft version; view acceptance history per version
 
+## Rendering a Policy Body
+Bodies are typed into a plain textarea, so most are written as blank-line-separated prose with no markup. `PolicyVersion::bodyHtml()` is the single render path — `wp_kses_post()` then `wpautop()`, the same treatment WordPress gives post content — so unmarked-up text arrives as real paragraphs and bodies that do carry markup are left alone. It feeds the booking/enrolment JSON (`GET /policies`), the signup form, and the admin version viewer, which therefore previews exactly what students see.
+
+The acceptance markup (`.us-policy` / `.us-policy-body`) is styled in `assets/css/frontend.css` as a bounded, vertically scrolling reading box with `overflow-wrap: break-word`, so a long policy or a pasted URL cannot force a horizontal scrollbar or push the accept checkbox out of view. `RegistrationPage` enqueues that stylesheet for the signup gate; `BookingPage` and `GroupClassPage` already did.
+
 ## REST API
 | Method   | Endpoint                                                        | Permission        |
 |----------|-----------------------------------------------------------------|-------------------|
@@ -74,3 +82,5 @@ cover every policy's current version or the registration is rejected.
 - `tests/Unit/Policy/PolicyVersionRepositoryTest.php`
 - `tests/Unit/Policy/AcceptanceRepositoryTest.php`
 - `tests/Unit/Policy/PolicyServiceTest.php`
+- `tests/Unit/Policy/PolicyControllerTest.php`
+- `tests/Unit/Policy/PolicyEndpointTest.php`

src/AdminMenu.php

@@ -5,6 +5,7 @@ namespace Unsupervised\Schedular;
 
 use Unsupervised\Schedular\Availability\AvailabilityController;
 use Unsupervised\Schedular\Availability\AvailabilityRepository;
+use Unsupervised\Schedular\Availability\WindowValidator;
 use Unsupervised\Schedular\Auth\AccessSettings;
 use Unsupervised\Schedular\Auth\InstructorController;
 use Unsupervised\Schedular\Auth\InviteRepository;
@@ -42,6 +43,12 @@ use Unsupervised\Schedular\Registration\QuestionRepository;
 
 class AdminMenu {
 
+	/**
+	 * Hook suffix of the availability screen, captured when the page is added so
+	 * its script loads on that screen only.
+	 */
+	private string $availabilityHook = '';
+
 	private AvailabilityController $availabilityController;
 	private LessonController $lessonController;
 	private OfferingController $offeringController;
@@ -58,7 +65,7 @@ class AdminMenu {
 	private PaymentReportController $paymentReportController;
 
 	public function __construct( AvailabilityRepository $availability, BookingRepository $bookings, OfferingRepository $offerings, QuestionRepository $questions, AnswerRepository $answers, PolicyRepository $policies, PolicyVersionRepository $policyVersions, PolicyService $policyService, AcceptanceRepository $acceptances, InviteRepository $invites, EnrollmentRepository $enrollments, GroupAccessRepository $groupAccess, StudioSettings $settings, PaymentRepository $payments, PaymentService $paymentService, BillingMethodResolver $resolver, RegistrationMailer $registrationMailer, CreditRepository $credits ) {
-		$this->availabilityController         = new AvailabilityController( $availability, $offerings );
+		$this->availabilityController         = new AvailabilityController( $availability, $offerings, new WindowValidator( $offerings ) );
 		$this->lessonController               = new LessonController( $bookings, $payments, $availability, $offerings, new LessonDetail( $answers, $questions, $acceptances, $policies, $policyVersions ) );
 		$this->offeringController             = new OfferingController( $offerings, new ClassSlotReconciler( $availability ) );
 		$this->questionController             = new QuestionController( $questions, $offerings );
@@ -76,9 +83,29 @@ class AdminMenu {
 
 	public function register(): void {
 		add_action( 'admin_menu', [ $this, 'addPages' ] );
+		add_action( 'admin_enqueue_scripts', [ $this, 'enqueueAssets' ] );
 		add_action( 'admin_post_' . PaymentReportController::EXPORT_ACTION, [ $this->paymentReportController, 'export' ] );
 	}
 
+	/**
+	 * Load a screen's script on that screen only.
+	 *
+	 * @param string $hookSuffix Screen the enqueue is running for.
+	 */
+	public function enqueueAssets( string $hookSuffix ): void {
+		if ( '' === $this->availabilityHook || $hookSuffix !== $this->availabilityHook ) {
+			return;
+		}
+
+		wp_enqueue_script(
+			'us-scheduler-availability-admin',
+			USC_PLUGIN_URL . 'assets/js/availability-admin.js',
+			[],
+			USC_VERSION,
+			true
+		);
+	}
+
 	public function addPages(): void {
 		$this->addStudioSeparators();
 
@@ -94,7 +121,7 @@ class AdminMenu {
 		);
 
 		// Instructor: manage their own availability.
-		add_menu_page(
+		$this->availabilityHook = (string) add_menu_page(
 			__( 'My Availability', 'unsupervised-schedular' ),
 			__( 'My Availability', 'unsupervised-schedular' ),
 			RoleManager::CAP_MANAGE_AVAILABILITY,

src/Auth/RegistrationPage.php

@@ -65,24 +65,21 @@ class RegistrationPage {
 		$registered = sanitize_key( Val::string( wp_unslash( $_GET['us_registered'] ?? '' ) ) );
 
 		if ( is_user_logged_in() ) {
-			if ( self::RESULT_INVITE === $registered ) {
+			// Both logged-in outcomes are dead ends without somewhere to go next,
-				// An invited student is done the moment they land here logged in,
+			// so both offer the same "continue" link to the configured page.
-				// so this is where their "continue" link belongs. The sign-in-page
+			wp_enqueue_style( 'us-scheduler' );
-				// fallback is deliberately not used: pointing someone who is
+			$link = $this->continueLink( $atts );
-				// already signed in at the login screen helps nobody.
-				$continue = $this->continueUrl( $this->successPageId( $atts ) );
-				$link     = null === $continue
-					? ''
-					: '<p><a href="' . esc_url( $continue ) . '">'
-						. esc_html__( 'Continue to your account', 'unsupervised-schedular' )
-						. '</a></p>';
 
+			if ( self::RESULT_INVITE === $registered ) {
+				// An invited student is done the moment they land here logged in.
 				return '<div class="us-register-form"><p class="us-success">'
 					. esc_html__( 'Your account has been created and you are now logged in.', 'unsupervised-schedular' )
 					. '</p>' . $link . '</div>';
 			}
 
-			return '<p>' . esc_html__( 'You already have an account and are logged in.', 'unsupervised-schedular' ) . '</p>';
+			return '<div class="us-register-form"><p>'
+				. esc_html__( 'You already have an account and are logged in.', 'unsupervised-schedular' )
+				. '</p>' . $link . '</div>';
 		}
 
 		// phpcs:ignore WordPress.Security.NonceVerification.Recommended -- token identifies the invite; the form submit is nonce-checked in maybeHandleSubmit.
@@ -116,6 +113,10 @@ class RegistrationPage {
 		$canRegister       = $open || $inviteValid;
 		$inviteOnlyMessage = $this->inviteOnlyMessage( $atts );
 
+		// The signup form carries the same policy-acceptance markup as the booking
+		// gate, so it needs the plugin stylesheet that formats it.
+		wp_enqueue_style( 'us-scheduler' );
+
 		// The two-step script only matters when there is a second step to reveal.
 		if ( $canRegister && '' === $successType && [] !== $accountQuestions ) {
 			wp_enqueue_script( 'us-scheduler-register' );
@@ -349,6 +350,40 @@ class RegistrationPage {
 		return $this->continueUrl( $loginPageId ) ?? wp_login_url();
 	}
 
+	/**
+	 * The "continue" paragraph shown to a logged-in visitor, or an empty string
+	 * when no destination page is configured. The link names the chosen page, so
+	 * the visitor knows where it goes before clicking; an untitled page falls
+	 * back to generic wording rather than reading "Continue to ".
+	 *
+	 * The sign-in-page fallback {@see loginUrl()} applies is deliberately not
+	 * used here: pointing someone who is already signed in at the login screen is
+	 * the same dead end with extra steps, so no link is better than that one.
+	 *
+	 * @param array<int|string, mixed> $atts
+	 */
+	private function continueLink( array $atts ): string {
+		$pageId   = $this->successPageId( $atts );
+		$continue = $this->continueUrl( $pageId );
+
+		if ( null === $continue ) {
+			return '';
+		}
+
+		$title = trim( Val::string( get_the_title( $pageId ) ) );
+		$label = '' === $title
+			? esc_html__( 'Continue to your account', 'unsupervised-schedular' )
+			: esc_html(
+				sprintf(
+					/* translators: %s: title of the page the student continues to. */
+					__( 'Continue to %s', 'unsupervised-schedular' ),
+					$title
+				)
+			);
+
+		return '<p><a href="' . esc_url( $continue ) . '">' . $label . '</a></p>';
+	}
+
 	/**
 	 * The chosen post-registration page's URL, or null when none is configured
 	 * (or it has since been deleted). Unlike {@see loginUrl()} this has no

src/Availability/AvailabilityController.php

@@ -13,6 +13,7 @@ class AvailabilityController {
 	public function __construct(
 		private AvailabilityRepository $repository,
 		private OfferingRepository $offerings,
+		private WindowValidator $validator,
 	) {}
 
 	public function renderPage(): void {
@@ -21,9 +22,11 @@ class AvailabilityController {
 		}
 
 		$instructorId = get_current_user_id();
+		$notice       = '';
+		$error        = '';
 
 		if ( isset( $_POST['usc_action'] ) && check_admin_referer( 'usc_availability_action' ) ) {
-			$this->handleFormAction( $instructorId );
+			[ $notice, $error ] = $this->handleFormAction( $instructorId );
 		}
 
 		$slots           = $this->repository->findByInstructor( $instructorId );
@@ -44,72 +47,144 @@ class AvailabilityController {
 		include USC_PLUGIN_DIR . 'templates/admin/availability.php';
 	}
 
-	private function handleFormAction( int $instructorId ): void {
+	/**
+	 * Run the submitted action and report what happened. Every branch returns a
+	 * message: a form that silently reloads leaves the instructor unable to tell
+	 * "saved 41 slots" from "saved nothing".
+	 *
+	 * @return array{string, string} Success notice and error message; each is
+	 *                               empty when it does not apply.
+	 */
+	private function handleFormAction( int $instructorId ): array {
 		// Nonce is verified by the caller (renderPage) before this method runs.
 		// phpcs:disable WordPress.Security.NonceVerification.Missing
 		$action = sanitize_key( Val::string( wp_unslash( $_POST['usc_action'] ?? '' ) ) );
 
 		if ( 'add' === $action ) {
-			$this->addSlot( $instructorId );
+			return $this->addSlot( $instructorId );
 		}
 
 		if ( 'delete' === $action ) {
-			$this->deleteOwnSlot( absint( Val::int( $_POST['slot_id'] ?? 0 ) ), $instructorId );
+			return $this->deleteOwnSlot( absint( Val::int( $_POST['slot_id'] ?? 0 ) ), $instructorId )
+				? [ __( 'Availability slot deleted.', 'unsupervised-schedular' ), '' ]
+				: [ '', __( 'That slot could not be deleted. It may already be booked, or belong to someone else.', 'unsupervised-schedular' ) ];
 		}
 
 		if ( 'bulk_delete' === $action ) {
 			// The array itself carries no data; each element is coerced and
 			// absint-sanitized individually below.
 			// phpcs:ignore WordPress.Security.ValidatedSanitizedInput
-			$rawIds = $_POST['slot_ids'] ?? [];
+			$rawIds  = $_POST['slot_ids'] ?? [];
+			$deleted = 0;
+			$failed  = 0;
+
 			foreach ( is_array( $rawIds ) ? $rawIds : [] as $rawId ) {
-				$this->deleteOwnSlot( absint( Val::int( $rawId ) ), $instructorId );
+				if ( $this->deleteOwnSlot( absint( Val::int( $rawId ) ), $instructorId ) ) {
+					++$deleted;
+					continue;
+				}
+
+				++$failed;
 			}
+
+			return $this->bulkDeleteResult( $deleted, $failed );
 		}
 		// phpcs:enable WordPress.Security.NonceVerification.Missing
+
+		return [ '', '' ];
+	}
+
+	/**
+	 * Wording for a bulk delete, which can partly succeed.
+	 *
+	 * @return array{string, string}
+	 */
+	private function bulkDeleteResult( int $deleted, int $failed ): array {
+		$notice = $deleted > 0
+			? sprintf(
+				/* translators: %d: number of availability slots deleted. */
+				_n( '%d slot deleted.', '%d slots deleted.', $deleted, 'unsupervised-schedular' ),
+				$deleted
+			)
+			: '';
+
+		$error = $failed > 0
+			? sprintf(
+				/* translators: %d: number of slots that could not be deleted. */
+				_n(
+					'%d slot could not be deleted — it may already be booked.',
+					'%d slots could not be deleted — they may already be booked.',
+					$failed,
+					'unsupervised-schedular'
+				),
+				$failed
+			)
+			: '';
+
+		if ( 0 === $deleted && 0 === $failed ) {
+			$error = __( 'No slots were selected.', 'unsupervised-schedular' );
+		}
+
+		return [ $notice, $error ];
 	}
 
 	/**
 	 * Delete a slot only when it exists and belongs to the given instructor.
-	 * The repository additionally refuses to delete booked slots.
+	 * The repository additionally refuses to delete booked slots. Returns whether
+	 * the row actually went away.
 	 */
-	private function deleteOwnSlot( int $slotId, int $instructorId ): void {
+	private function deleteOwnSlot( int $slotId, int $instructorId ): bool {
 		if ( $slotId <= 0 ) {
-			return;
+			return false;
 		}
 
 		$slot = $this->repository->findById( $slotId );
-		if ( $slot && $slot->instructorId === $instructorId ) {
+
-			$this->repository->delete( $slotId );
+		if ( null === $slot || $slot->instructorId !== $instructorId ) {
+			return false;
 		}
+
+		return $this->repository->delete( $slotId );
 	}
 
-	private function addSlot( int $instructorId ): void {
+	/**
+	 * Validate and persist a submitted window.
+	 *
+	 * @return array{string, string}
+	 */
+	private function addSlot( int $instructorId ): array {
 		// phpcs:disable WordPress.Security.NonceVerification.Missing
-		$startDt = AvailabilitySlot::normalizeDateTime( sanitize_text_field( Val::string( wp_unslash( $_POST['start_dt'] ?? '' ) ) ) );
+		$window = $this->validator->validate(
-		$endDt   = AvailabilitySlot::normalizeDateTime( sanitize_text_field( Val::string( wp_unslash( $_POST['end_dt'] ?? '' ) ) ) );
+			$instructorId,
-
+			sanitize_text_field( Val::string( wp_unslash( $_POST['start_dt'] ?? '' ) ) ),
-		// A window must start and end on the same day (weekly repeat covers longer
+			sanitize_text_field( Val::string( wp_unslash( $_POST['end_dt'] ?? '' ) ) ),
-		// ranges) and fit at least one lesson; it is stored as lesson-length slots.
+			absint( Val::int( $_POST['duration_minutes'] ?? 0 ) ),
-		if ( null === $startDt || null === $endDt || $endDt <= $startDt || substr( $startDt, 0, 10 ) !== substr( $endDt, 0, 10 ) ) {
+			absint( Val::int( $_POST['offering_id'] ?? 0 ) ),
-			return;
-		}
-
-		$offeringId = absint( Val::int( $_POST['offering_id'] ?? 0 ) );
-		$duration   = absint( Val::int( $_POST['duration_minutes'] ?? 0 ) );
-
-		$window = new AvailabilitySlot(
-			instructorId:    $instructorId,
-			startDt:         $startDt,
-			endDt:           $endDt,
-			durationMinutes: $duration > 0 ? $duration : 60,
-			offeringId:      $offeringId > 0 ? $offeringId : null,
 		);
 
+		if ( $window instanceof \WP_Error ) {
+			return [ '', $window->get_error_message() ];
+		}
+
 		$recurrence = sanitize_key( Val::string( wp_unslash( $_POST['recurrence'] ?? 'single' ) ) );
 		$weeks      = absint( Val::int( $_POST['weeks'] ?? 1 ) );
-
-		$this->repository->createFromWindow( $window, 'weekly' === $recurrence, $weeks );
 		// phpcs:enable WordPress.Security.NonceVerification.Missing
+
+		$ids = $this->repository->createFromWindow( $window, 'weekly' === $recurrence, $weeks );
+
+		// The window was valid, so it split into at least one slot — an empty
+		// result means every insert failed.
+		if ( [] === $ids ) {
+			return [ '', __( 'The availability could not be saved. Please try again.', 'unsupervised-schedular' ) ];
+		}
+
+		return [
+			sprintf(
+				/* translators: %d: number of bookable slots created. */
+				_n( 'Added %d bookable slot.', 'Added %d bookable slots.', count( $ids ), 'unsupervised-schedular' ),
+				count( $ids )
+			),
+			'',
+		];
 	}
 }

src/Availability/AvailabilityEndpoint.php

@@ -4,14 +4,13 @@ declare(strict_types=1);
 namespace Unsupervised\Schedular\Availability;
 
 use Unsupervised\Schedular\Auth\RoleManager;
-use Unsupervised\Schedular\Offering\OfferingRepository;
 use Unsupervised\Schedular\Val;
 
 class AvailabilityEndpoint {
 
 	public function __construct(
 		private AvailabilityRepository $repository,
-		private OfferingRepository $offerings,
+		private WindowValidator $validator,
 	) {}
 
 	/**
@@ -113,40 +112,18 @@ class AvailabilityEndpoint {
 	}
 
 	public function create( \WP_REST_Request $request ): \WP_REST_Response|\WP_Error {
-		$instructorId = get_current_user_id();
+		// Validation lives in WindowValidator so this endpoint and the admin form
-		$offeringId   = absint( Val::int( $request->get_param( 'offering_id' ) ) );
+		// enforce exactly the same rules.
-		$duration     = absint( Val::int( $request->get_param( 'duration_minutes' ) ) );
+		$window = $this->validator->validate(
-
+			get_current_user_id(),
-		// A slot may only be tied to an offering the instructor owns, so it can
+			Val::string( $request->get_param( 'start_dt' ) ),
-		// never inherit another instructor's price or payment routing at booking.
+			Val::string( $request->get_param( 'end_dt' ) ),
-		if ( $offeringId > 0 ) {
+			absint( Val::int( $request->get_param( 'duration_minutes' ) ) ),
-			$offering = $this->offerings->findById( $offeringId );
+			absint( Val::int( $request->get_param( 'offering_id' ) ) ),
-			if ( null === $offering || $offering->instructorId !== $instructorId ) {
-				return new \WP_Error( 'invalid_offering', __( 'That offering is not available.', 'unsupervised-schedular' ), [ 'status' => 400 ] );
-			}
-		}
-
-		$startDt = AvailabilitySlot::normalizeDateTime( Val::string( $request->get_param( 'start_dt' ) ) );
-		$endDt   = AvailabilitySlot::normalizeDateTime( Val::string( $request->get_param( 'end_dt' ) ) );
-
-		if ( null === $startDt || null === $endDt || $endDt <= $startDt ) {
-			return new \WP_Error( 'invalid_datetime', __( 'Provide a valid start and end, with the end after the start.', 'unsupervised-schedular' ), [ 'status' => 400 ] );
-		}
-
-		if ( substr( $startDt, 0, 10 ) !== substr( $endDt, 0, 10 ) ) {
-			return new \WP_Error( 'invalid_window', __( 'Availability must start and end on the same day. Use the weekly repeat to cover multiple weeks.', 'unsupervised-schedular' ), [ 'status' => 400 ] );
-		}
-
-		$window = new AvailabilitySlot(
-			instructorId:    $instructorId,
-			startDt:         $startDt,
-			endDt:           $endDt,
-			durationMinutes: $duration > 0 ? $duration : 60,
-			offeringId:      $offeringId > 0 ? $offeringId : null,
 		);
 
-		if ( [] === $window->splitByDuration() ) {
+		if ( $window instanceof \WP_Error ) {
-			return new \WP_Error( 'invalid_window', __( 'The availability window is shorter than the lesson length.', 'unsupervised-schedular' ), [ 'status' => 400 ] );
+			return $window;
 		}
 
 		$ids = $this->repository->createFromWindow(
@@ -155,6 +132,12 @@ class AvailabilityEndpoint {
 			absint( Val::int( $request->get_param( 'weeks' ) ) )
 		);
 
+		// A valid window splits into at least one slot, so nothing written means
+		// every insert failed.
+		if ( [] === $ids ) {
+			return new \WP_Error( 'not_saved', __( 'The availability could not be saved.', 'unsupervised-schedular' ), [ 'status' => 500 ] );
+		}
+
 		return new \WP_REST_Response( [ 'ids' => $ids ], 201 );
 	}
 

src/Availability/AvailabilityRepository.php

@@ -11,8 +11,14 @@ class AvailabilityRepository {
 		$this->table = $db->prefix . 'us_availability';
 	}
 
+	/**
+	 * Insert one slot row. Returns its id, or 0 when the write failed —
+	 * `insert_id` still holds the *previous* statement's id after a failed
+	 * insert, so returning it unconditionally made a failed write look like a
+	 * successful one.
+	 */
 	public function insert( AvailabilitySlot $slot ): int {
-		$this->db->insert(
+		$written = $this->db->insert(
 			$this->table,
 			[
 				'instructor_id'    => $slot->instructorId,
@@ -27,7 +33,7 @@ class AvailabilityRepository {
 			[ '%d', '%d', '%s', '%s', '%d', '%d', '%d', '%s' ]
 		);
 
-		return $this->db->insert_id;
+		return false === $written ? 0 : $this->db->insert_id;
 	}
 
 	/**
@@ -42,9 +48,17 @@ class AvailabilityRepository {
 		$ids = [];
 
 		foreach ( $window->splitByDuration() as $slot ) {
-			$ids = $weekly
+			if ( $weekly ) {
-				? array_merge( $ids, $this->createWeeklySeries( $slot, $weeks ) )
+				$ids = array_merge( $ids, $this->createWeeklySeries( $slot, $weeks ) );
-				: [ ...$ids, $this->insert( $slot ) ];
+				continue;
+			}
+
+			$id = $this->insert( $slot );
+
+			// A failed insert returns 0; it must not reach the caller as an id.
+			if ( $id > 0 ) {
+				$ids[] = $id;
+			}
 		}
 
 		return $ids;
@@ -55,10 +69,14 @@ class AvailabilityRepository {
 	 * separate row one week apart, all sharing a `recurrence_group` (the id of the
 	 * first row).
 	 *
+	 * The count is clamped to `AvailabilitySlot::MAX_WEEKLY_OCCURRENCES`. The
+	 * form's `max` attribute says the same, but only this is binding — a
+	 * hand-crafted POST used to be able to ask for an unbounded number of rows.
+	 *
 	 * @return list<int> Inserted slot IDs.
 	 */
 	public function createWeeklySeries( AvailabilitySlot $first, int $occurrences ): array {
-		$occurrences = max( 1, $occurrences );
+		$occurrences = max( 1, min( AvailabilitySlot::MAX_WEEKLY_OCCURRENCES, $occurrences ) );
 		$start       = new \DateTimeImmutable( $first->startDt );
 		$end         = new \DateTimeImmutable( $first->endDt );
 
@@ -79,6 +97,13 @@ class AvailabilityRepository {
 				)
 			);
 
+			// A failed insert returns 0. Skipping it keeps a bogus id out of the
+			// returned list and, more importantly, stops 0 becoming the series'
+			// recurrence group — which would orphan every later occurrence.
+			if ( $id <= 0 ) {
+				continue;
+			}
+
 			if ( 0 === $groupId ) {
 				$groupId = $id;
 				$this->setRecurrenceGroup( $id, $groupId );

src/Availability/AvailabilitySlot.php

@@ -7,6 +7,23 @@ use Unsupervised\Schedular\Val;
 
 class AvailabilitySlot {
 
+	/** Lesson length used when none was submitted. */
+	public const DEFAULT_DURATION_MINUTES = 60;
+
+	/**
+	 * Lesson lengths a window can be split into, offered by the availability
+	 * form. The form hides the ones a given window is too short for.
+	 *
+	 * @var list<int>
+	 */
+	public const DURATION_CHOICES = [ 30, 60 ];
+
+	/**
+	 * Ceiling on a weekly series, matching the form's `max`. Enforced in the
+	 * repository too, so a hand-crafted POST cannot ask for ten thousand rows.
+	 */
+	public const MAX_WEEKLY_OCCURRENCES = 52;
+
 	public function __construct(
 		public readonly int $instructorId,
 		public readonly string $startDt,

src/Availability/WindowValidator.php

@@ -0,0 +1,105 @@
+<?php
+declare(strict_types=1);
+
+namespace Unsupervised\Schedular\Availability;
+
+use Unsupervised\Schedular\Offering\OfferingRepository;
+
+/**
+ * Validates a submitted availability window.
+ *
+ * The admin form and the REST endpoint both accept the same window, and used to
+ * check it independently — the endpoint returning a specific 400 for each
+ * failure while the form simply returned, saving nothing and saying nothing. A
+ * 30-minute window submitted with the default 60-minute lesson length was the
+ * visible symptom: no rows, no error, no clue. Both callers now come through
+ * here, so neither can drift from the other again.
+ *
+ * Every rejection is a `WP_Error` carrying a message written for the person who
+ * submitted the form: the endpoint returns it as-is (the `status` data makes it
+ * a 400), and the admin screen shows `get_error_message()` in a notice.
+ */
+class WindowValidator {
+
+	public function __construct( private OfferingRepository $offerings ) {}
+
+	/**
+	 * Check a submitted window and return it ready to persist.
+	 *
+	 * @param int    $instructorId    Instructor the window belongs to.
+	 * @param string $rawStart        Submitted start, in any form {@see AvailabilitySlot::normalizeDateTime()} accepts.
+	 * @param string $rawEnd          Submitted end, likewise.
+	 * @param int    $durationMinutes Lesson length the window is split into; 0 falls back to the 60-minute default.
+	 * @param int    $offeringId      Offering the slots are tied to, or 0 for any private lesson.
+	 *
+	 * @return AvailabilitySlot|\WP_Error The window, or why it was rejected.
+	 */
+	public function validate( int $instructorId, string $rawStart, string $rawEnd, int $durationMinutes, int $offeringId ): AvailabilitySlot|\WP_Error {
+		$startDt = AvailabilitySlot::normalizeDateTime( $rawStart );
+		$endDt   = AvailabilitySlot::normalizeDateTime( $rawEnd );
+
+		if ( null === $startDt || null === $endDt ) {
+			return new \WP_Error(
+				'invalid_datetime',
+				__( 'Enter a valid start and end date and time.', 'unsupervised-schedular' ),
+				[ 'status' => 400 ]
+			);
+		}
+
+		if ( $endDt <= $startDt ) {
+			return new \WP_Error(
+				'invalid_datetime',
+				__( 'The end time must be after the start time.', 'unsupervised-schedular' ),
+				[ 'status' => 400 ]
+			);
+		}
+
+		if ( substr( $startDt, 0, 10 ) !== substr( $endDt, 0, 10 ) ) {
+			return new \WP_Error(
+				'invalid_window',
+				__( 'Availability must start and end on the same day. Use the weekly repeat to cover multiple weeks.', 'unsupervised-schedular' ),
+				[ 'status' => 400 ]
+			);
+		}
+
+		// A slot may only be tied to an offering the instructor owns, so it can
+		// never inherit another instructor's price or payment routing at booking.
+		if ( $offeringId > 0 ) {
+			$offering = $this->offerings->findById( $offeringId );
+
+			if ( null === $offering || $offering->instructorId !== $instructorId ) {
+				return new \WP_Error(
+					'invalid_offering',
+					__( 'That offering is not available.', 'unsupervised-schedular' ),
+					[ 'status' => 400 ]
+				);
+			}
+		}
+
+		$duration = $durationMinutes > 0 ? $durationMinutes : AvailabilitySlot::DEFAULT_DURATION_MINUTES;
+
+		$window = new AvailabilitySlot(
+			instructorId:    $instructorId,
+			startDt:         $startDt,
+			endDt:           $endDt,
+			durationMinutes: $duration,
+			offeringId:      $offeringId > 0 ? $offeringId : null,
+		);
+
+		// The window is stored as lesson-length slots, so one that cannot fit a
+		// single lesson would persist nothing at all.
+		if ( [] === $window->splitByDuration() ) {
+			return new \WP_Error(
+				'invalid_window',
+				sprintf(
+					/* translators: %d: the selected lesson length, in minutes. */
+					__( 'This window is shorter than the %d-minute lesson length, so it holds no bookable slots. Choose a shorter lesson length or a longer window.', 'unsupervised-schedular' ),
+					$duration
+				),
+				[ 'status' => 400 ]
+			);
+		}
+
+		return $window;
+	}
+}

src/BlockPreview.php

@@ -86,13 +86,13 @@ class BlockPreview {
 	private static function upcomingLessons(): string {
 		return sprintf(
 			'<div class="us-my-lessons"><h3>%s</h3>'
-			. '<div class="us-my-lesson"><span class="us-my-lesson-info">'
+			. '<div class="us-my-lesson"><div class="us-my-lesson-info">'
 			. '<strong class="us-my-lesson-title">%s <span class="us-my-lesson-duration">(30 min)</span></strong>'
-			. '<span class="us-my-lesson-when">%s</span></span>'
+			. '<span class="us-my-lesson-when">%s</span></div>'
-			. '<span class="us-my-lesson-actions">'
+			. '<div class="us-my-lesson-actions">'
 			. '<span class="us-lesson-status us-lesson-status-confirmed">%s</span>'
 			. '<button type="button" class="us-cancel-lesson" disabled>%s</button>'
-			. '</span></div></div>',
+			. '</div></div></div>',
 			esc_html__( 'Your upcoming lessons', 'unsupervised-schedular' ),
 			esc_html__( 'Piano Lesson', 'unsupervised-schedular' ),
 			esc_html__( 'Monday · 4:00 PM–4:30 PM', 'unsupervised-schedular' ),

src/Policy/PolicyController.php

@@ -19,20 +19,35 @@ class PolicyController {
 			wp_die( esc_html__( 'You do not have permission to manage policies.', 'unsupervised-schedular' ) );
 		}
 
+		$notice        = '';
+		$viewVersionId = 0;
+
 		if ( isset( $_POST['usc_action'] ) && check_admin_referer( 'usc_policy_action' ) ) {
-			$this->handleFormAction();
+			[ $notice, $viewVersionId ] = $this->handleFormAction();
 		}
 
-		// phpcs:ignore WordPress.Security.NonceVerification.Recommended -- read-only policy selector.
+		// phpcs:disable WordPress.Security.NonceVerification.Recommended -- read-only policy/version selectors.
-		$policyId       = absint( Val::int( $_GET['policy_id'] ?? 0 ) );
+		$policyId = absint( Val::int( $_GET['policy_id'] ?? 0 ) );
+		if ( 0 === $viewVersionId ) {
+			$viewVersionId = absint( Val::int( $_GET['version_id'] ?? 0 ) );
+		}
+		// phpcs:enable WordPress.Security.NonceVerification.Recommended
+
 		$policyList     = $this->policies->findAll();
 		$selectedPolicy = $policyId > 0 ? $this->policies->findById( $policyId ) : null;
 		$policyVersions = null !== $selectedPolicy ? $this->versions->findByPolicy( (int) $selectedPolicy->id ) : null;
+		$viewedVersion  = null !== $selectedPolicy ? $this->loadVersionForPolicy( (int) $selectedPolicy->id, $viewVersionId ) : null;
 
 		include USC_PLUGIN_DIR . 'templates/admin/policies.php';
 	}
 
-	private function handleFormAction(): void {
+	/**
+	 * Process the posted action.
+	 *
+	 * @return array{string, int} Status notice, and the version to open in the
+	 *                            viewer (0 to leave the current selection alone).
+	 */
+	private function handleFormAction(): array {
 		// Nonce is verified by the caller (renderPage) before this method runs.
 		// phpcs:disable WordPress.Security.NonceVerification.Missing
 		$action = sanitize_key( Val::string( wp_unslash( $_POST['usc_action'] ?? '' ) ) );
@@ -53,12 +68,12 @@ class PolicyController {
 				$this->service->createPolicy( $title, $slug, $scope );
 			}
 
-			return;
+			return [ '', 0 ];
 		}
 
 		$policyId = absint( Val::int( $_POST['policy_id'] ?? 0 ) );
 		if ( $policyId <= 0 || null === $this->policies->findById( $policyId ) ) {
-			return;
+			return [ '', 0 ];
 		}
 
 		if ( 'add_version' === $action ) {
@@ -66,6 +81,40 @@ class PolicyController {
 			$this->service->addDraftVersion( $policyId, $body );
 		}
 
+		if ( 'edit_version' === $action ) {
+			$source = $this->loadVersionForPolicy( $policyId, absint( Val::int( $_POST['version_id'] ?? 0 ) ) );
+			if ( null === $source ) {
+				return [ '', 0 ];
+			}
+
+			$body = wp_kses_post( Val::string( wp_unslash( $_POST['body'] ?? '' ) ) );
+
+			// A draft has never been shown to a student, so it is edited in place.
+			// A published (or archived) version is what students accepted, so an
+			// edit branches a new draft and leaves the original untouched.
+			if ( PolicyVersion::STATUS_DRAFT === $source->status ) {
+				$this->versions->updateBody( (int) $source->id, $body );
+
+				return [
+					sprintf(
+						/* translators: %d: the edited version number. */
+						__( 'Draft version %d was updated.', 'unsupervised-schedular' ),
+						$source->versionNumber
+					),
+					(int) $source->id,
+				];
+			}
+
+			return [
+				sprintf(
+					/* translators: %d: the version number the edit was based on. */
+					__( 'Your changes to version %d were saved as a new draft version.', 'unsupervised-schedular' ),
+					$source->versionNumber
+				),
+				$this->service->addDraftVersion( $policyId, $body ),
+			];
+		}
+
 		if ( 'publish_version' === $action ) {
 			$versionId = absint( Val::int( $_POST['version_id'] ?? 0 ) );
 			if ( $versionId > 0 ) {
@@ -73,5 +122,20 @@ class PolicyController {
 			}
 		}
 		// phpcs:enable WordPress.Security.NonceVerification.Missing
+
+		return [ '', 0 ];
+	}
+
+	/**
+	 * Load a version by id, confirming it belongs to the given policy.
+	 */
+	private function loadVersionForPolicy( int $policyId, int $versionId ): ?PolicyVersion {
+		if ( $versionId <= 0 ) {
+			return null;
+		}
+
+		$version = $this->versions->findById( $versionId );
+
+		return null !== $version && $version->policyId === $policyId ? $version : null;
 	}
 }

src/Policy/PolicyEndpoint.php

@@ -104,9 +104,9 @@ class PolicyEndpoint {
 				'policy_version_id' => $version->id,
 				'version_number'    => $version->versionNumber,
 				// Bodies are kses'd on every write path, but the booking JS renders
-				// this HTML raw — sanitise at output too so a missed write path can
+				// this HTML raw — bodyHtml() sanitises at output too, so a missed
-				// never become stored XSS.
+				// write path can never become stored XSS.
-				'body'              => wp_kses_post( (string) $version->body ),
+				'body'              => $version->bodyHtml(),
 			];
 		}
 

src/Policy/PolicyVersion.php

@@ -42,6 +42,19 @@ class PolicyVersion {
 		return self::STATUS_PUBLISHED === $this->status;
 	}
 
+	/**
+	 * The body as display-ready HTML.
+	 *
+	 * Policy bodies are typed into a plain textarea, so most are written as
+	 * blank-line-separated prose with no markup at all — dropped into a page
+	 * as-is that collapses into one unreadable run of text. Running the same
+	 * `wpautop()` WordPress applies to post content turns those breaks into
+	 * paragraphs, and leaves bodies that do carry markup alone.
+	 */
+	public function bodyHtml(): string {
+		return wpautop( wp_kses_post( (string) $this->body ) );
+	}
+
 	/**
 	 * Returns a plain array representation of the version.
 	 *

src/RestRegistrar.php

@@ -5,6 +5,7 @@ namespace Unsupervised\Schedular;
 
 use Unsupervised\Schedular\Availability\AvailabilityEndpoint;
 use Unsupervised\Schedular\Availability\AvailabilityRepository;
+use Unsupervised\Schedular\Availability\WindowValidator;
 use Unsupervised\Schedular\Booking\BookingEndpoint;
 use Unsupervised\Schedular\Booking\BookingRepository;
 use Unsupervised\Schedular\Booking\CancellationPolicy;
@@ -37,7 +38,7 @@ class RestRegistrar {
 	private PaymentEndpoint $paymentEndpoint;
 
 	public function __construct( AvailabilityRepository $availability, BookingRepository $bookings, OfferingRepository $offerings, QuestionRepository $questions, PolicyRepository $policies, PolicyVersionRepository $policyVersions, PolicyService $policyService, RegistrationGate $gate, EnrollmentRepository $enrollments, GroupAccessRepository $groupAccess, PaymentService $paymentService ) {
-		$this->availabilityEndpoint = new AvailabilityEndpoint( $availability, $offerings );
+		$this->availabilityEndpoint = new AvailabilityEndpoint( $availability, new WindowValidator( $offerings ) );
 		$this->bookingEndpoint      = new BookingEndpoint( $availability, $bookings, $offerings, $gate, $paymentService, new CancellationPolicy( new StudioSettings() ) );
 		$this->offeringEndpoint     = new OfferingEndpoint( $offerings, $groupAccess );
 		$this->questionEndpoint     = new QuestionEndpoint( $questions, $offerings );

templates/admin/availability.php

@@ -13,8 +13,12 @@ if (! defined('ABSPATH')) {
  * @var list<array{date: string, slots: list<\Unsupervised\Schedular\Availability\AvailabilitySlot>}> $weekDays
  * @var string $prevWeek
  * @var string $nextWeek
+ * @var string $notice Success message from the submitted action; empty when none.
+ * @var string $error  Failure message from the submitted action; empty when none.
  */
 
+use Unsupervised\Schedular\Availability\AvailabilitySlot;
+
 $baseUrl = admin_url('admin.php?page=us-availability');
 
 $deleteForm = static function (\Unsupervised\Schedular\Availability\AvailabilitySlot $slot): void {
@@ -33,9 +37,16 @@ $deleteForm = static function (\Unsupervised\Schedular\Availability\Availability
 <div class="wrap">
     <h1><?php esc_html_e('My Availability', 'unsupervised-schedular'); ?></h1>
 
+    <?php if ('' !== $notice) : ?>
+        <div class="notice notice-success is-dismissible"><p><?php echo esc_html($notice); ?></p></div>
+    <?php endif; ?>
+    <?php if ('' !== $error) : ?>
+        <div class="notice notice-error is-dismissible"><p><?php echo esc_html($error); ?></p></div>
+    <?php endif; ?>
+
     <h2><?php esc_html_e('Add Availability', 'unsupervised-schedular'); ?></h2>
     <p><?php esc_html_e('The window must start and end on the same day. It is split into bookable slots of the chosen lesson length — for example, 9:00 AM–4:00 PM with 60-minute lessons creates seven slots.', 'unsupervised-schedular'); ?></p>
-    <form method="post">
+    <form method="post" id="usc-add-availability">
         <?php wp_nonce_field('usc_availability_action'); ?>
         <input type="hidden" name="usc_action" value="add">
         <table class="form-table">
@@ -51,9 +62,20 @@ $deleteForm = static function (\Unsupervised\Schedular\Availability\Availability
                 <th><label for="duration_minutes"><?php esc_html_e('Lesson length (minutes)', 'unsupervised-schedular'); ?></label></th>
                 <td>
                     <select name="duration_minutes" id="duration_minutes">
-                        <option value="30">30</option>
+                        <?php foreach (AvailabilitySlot::DURATION_CHOICES as $choice) : ?>
-                        <option value="60" selected>60</option>
+                            <option value="<?php echo esc_attr((string) $choice); ?>" <?php selected($choice, AvailabilitySlot::DEFAULT_DURATION_MINUTES); ?>>
+                                <?php echo esc_html((string) $choice); ?>
+                            </option>
+                        <?php endforeach; ?>
                     </select>
+                    <?php
+                    // Filled and revealed by availability-admin.js when the entered
+                    // window is too short for every lesson length. The wording lives
+                    // here so it stays translatable.
+                    ?>
+                    <p class="description usc-duration-warning" id="usc-duration-warning" hidden>
+                        <?php esc_html_e('This window is too short for any lesson length. Lengthen the window or it cannot be saved.', 'unsupervised-schedular'); ?>
+                    </p>
                 </td>
             </tr>
             <tr>
@@ -73,7 +95,7 @@ $deleteForm = static function (\Unsupervised\Schedular\Availability\Availability
                     <label><input type="radio" name="recurrence" value="single" checked> <?php esc_html_e('One-off', 'unsupervised-schedular'); ?></label>
                     &nbsp;
                     <label><input type="radio" name="recurrence" value="weekly"> <?php esc_html_e('Weekly for', 'unsupervised-schedular'); ?></label>
-                    <input type="number" name="weeks" min="1" max="52" value="12" style="width:5em;"> <?php esc_html_e('weeks', 'unsupervised-schedular'); ?>
+                    <input type="number" name="weeks" min="1" max="<?php echo esc_attr((string) AvailabilitySlot::MAX_WEEKLY_OCCURRENCES); ?>" value="12" style="width:5em;"> <?php esc_html_e('weeks', 'unsupervised-schedular'); ?>
                 </td>
             </tr>
         </table>

templates/admin/policies.php

@@ -12,11 +12,17 @@ if (! defined('ABSPATH')) {
  * @var list<\Unsupervised\Schedular\Policy\Policy>        $policyList
  * @var \Unsupervised\Schedular\Policy\Policy|null         $selectedPolicy
  * @var list<\Unsupervised\Schedular\Policy\PolicyVersion>|null $policyVersions
+ * @var \Unsupervised\Schedular\Policy\PolicyVersion|null  $viewedVersion  Version opened in the viewer, if any.
+ * @var string                                            $notice         Status message from the last save.
  */
 ?>
 <div class="wrap">
     <h1><?php esc_html_e('Policies', 'unsupervised-schedular'); ?></h1>
 
+    <?php if ('' !== $notice) : ?>
+        <div class="notice notice-success is-dismissible"><p><?php echo esc_html($notice); ?></p></div>
+    <?php endif; ?>
+
     <h2><?php esc_html_e('Add Policy', 'unsupervised-schedular'); ?></h2>
     <form method="post">
         <?php wp_nonce_field('usc_policy_action'); ?>
@@ -98,6 +104,18 @@ if (! defined('ABSPATH')) {
                             <td><?php echo esc_html($version->status); ?></td>
                             <td><?php echo $version->publishedAt ? esc_html($version->publishedAt) : '&mdash;'; ?></td>
                             <td>
+                                <a href="<?php echo esc_url(
+                                    add_query_arg(
+                                        [
+                                            'page'      => 'us-policies',
+                                            'policy_id' => (string) $selectedPolicy->id,
+                                            'version_id' => (string) $version->id,
+                                        ],
+                                        admin_url('admin.php')
+                                    )
+                                ); ?>" class="button button-small">
+                                    <?php esc_html_e('View', 'unsupervised-schedular'); ?>
+                                </a>
                                 <?php if (PolicyVersion::STATUS_PUBLISHED !== $version->status) : ?>
                                     <form method="post" style="display:inline;">
                                         <?php wp_nonce_field('usc_policy_action'); ?>
@@ -117,5 +135,48 @@ if (! defined('ABSPATH')) {
                 </tbody>
             </table>
         <?php endif; ?>
+
+        <?php if (null !== $viewedVersion) : ?>
+            <hr>
+            <h3>
+                <?php echo esc_html(sprintf(
+                    /* translators: 1: version number, 2: version status. */
+                    __('Version %1$d (%2$s)', 'unsupervised-schedular'),
+                    $viewedVersion->versionNumber,
+                    $viewedVersion->status
+                )); ?>
+            </h3>
+
+            <?php // Rendered exactly as the booking and signup gates render it, so this doubles as a preview. ?>
+            <div class="us-policy-version-body" style="background:#fff;border:1px solid #c3c4c7;padding:0 1em;max-width:50em;overflow-wrap:break-word;">
+                <?php echo wp_kses_post($viewedVersion->bodyHtml()); ?>
+            </div>
+
+            <?php $editingDraft = PolicyVersion::STATUS_DRAFT === $viewedVersion->status; ?>
+            <h4><?php esc_html_e('Edit', 'unsupervised-schedular'); ?></h4>
+            <p class="description">
+                <?php
+                echo esc_html(
+                    $editingDraft
+                        ? __('This version is still a draft, so your changes are saved to it directly.', 'unsupervised-schedular')
+                        : __('This version has been published, so saving an edit creates a new draft version from this text and leaves the published one untouched.', 'unsupervised-schedular')
+                );
+                ?>
+            </p>
+            <form method="post">
+                <?php wp_nonce_field('usc_policy_action'); ?>
+                <input type="hidden" name="usc_action" value="edit_version">
+                <input type="hidden" name="policy_id" value="<?php echo esc_attr((string) $selectedPolicy->id); ?>">
+                <input type="hidden" name="version_id" value="<?php echo esc_attr((string) $viewedVersion->id); ?>">
+                <textarea name="body" rows="12" class="large-text"><?php echo esc_textarea((string) $viewedVersion->body); ?></textarea>
+                <?php
+                submit_button(
+                    $editingDraft
+                        ? esc_html__('Save Draft', 'unsupervised-schedular')
+                        : esc_html__('Save as New Draft', 'unsupervised-schedular')
+                );
+                ?>
+            </form>
+        <?php endif; ?>
     <?php endif; ?>
 </div>

templates/frontend/register-page.php

@@ -108,7 +108,7 @@ $renderQuestionField = static function (Question $question): void {
                             <?php foreach ($policyForms as $form) : ?>
                                 <div class="us-policy">
                                     <h4><?php echo esc_html($form['policy']->title); ?></h4>
-                                    <div class="us-policy-body"><?php echo wp_kses_post((string) $form['version']->body); ?></div>
+                                    <div class="us-policy-body"><?php echo wp_kses_post($form['version']->bodyHtml()); ?></div>
                                     <label>
                                         <input type="checkbox" name="accept[]" value="<?php echo esc_attr((string) $form['version']->id); ?>" required>
                                         <?php

tests/Unit/Auth/RegistrationPageTest.php

@@ -37,6 +37,8 @@ class RegistrationPageTest extends TestCase
         Functions\when('sanitize_email')->alias(static fn ($v) => $v);
         Functions\when('absint')->alias(static fn ($v) => (int) $v);
         Functions\when('current_time')->justReturn('2024-01-01 00:00:00');
+        Functions\when('wp_enqueue_style')->justReturn(null);
+        Functions\when('wp_enqueue_script')->justReturn(null);
 
         $invites   = Mockery::mock(InviteRepository::class);
         $policies  = Mockery::mock(PolicyRepository::class);
@@ -495,11 +497,61 @@ class RegistrationPageTest extends TestCase
         Functions\when('is_user_logged_in')->justReturn(true);
         Functions\when('sanitize_key')->alias(static fn ($v) => strtolower((string) $v));
         Functions\expect('get_permalink')->once()->with(4)->andReturn('http://home.test/welcome/');
+        Functions\when('get_the_title')->justReturn('Book a Lesson');
 
         $html = $this->ctx['page']->render([ 'loginPageId' => 4 ]);
 
         self::assertStringContainsString('now logged in', $html);
         self::assertStringContainsString('href="http://home.test/welcome/"', $html);
+        // The link names its destination rather than saying "your account".
+        self::assertStringContainsString('Continue to Book a Lesson', $html);
+    }
+
+    public function testContinueLinkFallsBackToGenericWordingForAnUntitledPage(): void
+    {
+        Functions\when('is_user_logged_in')->justReturn(true);
+        Functions\when('sanitize_key')->alias(static fn ($v) => strtolower((string) $v));
+        Functions\when('get_permalink')->justReturn('http://home.test/welcome/');
+        Functions\when('get_the_title')->justReturn('  ');
+
+        // An untitled page must not produce a link reading "Continue to ".
+        $html = $this->ctx['page']->render([ 'loginPageId' => 4 ]);
+
+        self::assertStringContainsString('Continue to your account', $html);
+        self::assertStringContainsString('href="http://home.test/welcome/"', $html);
+    }
+
+    public function testAlreadyLoggedInVisitorIsLinkedToTheChosenPage(): void
+    {
+        // No us_registered flag: someone who simply happens to be signed in and
+        // lands on the registration page. They still need a way onward.
+        Functions\when('is_user_logged_in')->justReturn(true);
+        Functions\when('sanitize_key')->alias(static fn ($v) => strtolower((string) $v));
+        Functions\expect('get_permalink')->once()->with(4)->andReturn('http://home.test/welcome/');
+        Functions\when('get_the_title')->justReturn('Book a Lesson');
+
+        $html = $this->ctx['page']->render([ 'loginPageId' => 4 ]);
+
+        self::assertStringContainsString('already have an account', $html);
+        self::assertStringContainsString('href="http://home.test/welcome/"', $html);
+        self::assertStringContainsString('Continue to Book a Lesson', $html);
+        // Not the just-registered message — that branch needs its own flag.
+        self::assertStringNotContainsString('us-success', $html);
+    }
+
+    public function testAlreadyLoggedInVisitorGetsNoLinkWithoutAChosenPage(): void
+    {
+        Functions\when('is_user_logged_in')->justReturn(true);
+        Functions\when('sanitize_key')->alias(static fn ($v) => strtolower((string) $v));
+        Functions\when('get_permalink')->justReturn(false);
+
+        // A deleted page resolves to false, which must not become a broken link.
+        $html = $this->ctx['page']->render([ 'loginPageId' => 4 ]);
+
+        self::assertStringContainsString('already have an account', $html);
+        self::assertStringNotContainsString('<a href', $html);
+
+        self::assertStringNotContainsString('<a href', $this->ctx['page']->render([]));
     }
 
     public function testContinueUrlIsNullWithoutAResolvablePage(): void

tests/Unit/Availability/AvailabilityControllerTest.php

@@ -8,6 +8,7 @@ use Mockery;
 use Unsupervised\Schedular\Availability\AvailabilityController;
 use Unsupervised\Schedular\Availability\AvailabilityRepository;
 use Unsupervised\Schedular\Availability\AvailabilitySlot;
+use Unsupervised\Schedular\Availability\WindowValidator;
 use Unsupervised\Schedular\Offering\OfferingRepository;
 use Unsupervised\Schedular\Tests\Unit\TestCase;
 
@@ -23,7 +24,7 @@ class AvailabilityControllerTest extends TestCase
 
         $this->repository = Mockery::mock(AvailabilityRepository::class);
         $this->offerings  = Mockery::mock(OfferingRepository::class);
-        $this->controller = new AvailabilityController($this->repository, $this->offerings);
+        $this->controller = new AvailabilityController($this->repository, $this->offerings, new WindowValidator($this->offerings));
 
         $_POST = [];
         $_GET  = [];
@@ -39,6 +40,7 @@ class AvailabilityControllerTest extends TestCase
         Functions\when('absint')->alias(static fn ($value) => abs((int) $value));
         Functions\when('get_option')->justReturn(1);
         Functions\when('current_time')->justReturn('2026-07-06');
+        Functions\when('selected')->justReturn('');
         Functions\when('admin_url')->justReturn('admin.php?page=us-availability');
         Functions\when('add_query_arg')->justReturn('admin.php?page=us-availability&usc_view=week');
         Functions\when('wp_nonce_field')->justReturn('');
@@ -131,6 +133,159 @@ class AvailabilityControllerTest extends TestCase
         self::assertStringNotContainsString('name="slot_ids[]" form="usc-bulk-delete-form" value="6"', $html);
     }
 
+    /**
+     * The reported bug: a 30-minute window submitted with the lesson length left
+     * on 60 saved nothing and said nothing. It must now say why.
+     */
+    public function testAddShowsAnErrorWhenTheWindowIsShorterThanTheLessonLength(): void
+    {
+        $_POST = [
+            'usc_action'       => 'add',
+            'start_dt'         => '2026-09-10T17:30',
+            'end_dt'           => '2026-09-10T18:00',
+            'duration_minutes' => '60',
+        ];
+
+        $this->repository->shouldNotReceive('createFromWindow');
+        $this->repository->shouldReceive('findByInstructor')->once()->with(3)->andReturn([]);
+
+        $html = $this->render();
+
+        self::assertStringContainsString('notice-error', $html);
+        self::assertStringContainsString('60-minute lesson length', $html);
+        self::assertStringNotContainsString('notice-success', $html);
+    }
+
+    /** @return array<string, array{array<string, string>, string}> */
+    public static function invalidWindows(): array
+    {
+        return [
+            'unparseable start' => [['start_dt' => 'whenever', 'end_dt' => '2026-09-10T18:00'], 'valid start and end'],
+            'end before start'  => [['start_dt' => '2026-09-10T18:00', 'end_dt' => '2026-09-10T17:00'], 'after the start time'],
+            'spans two days'    => [['start_dt' => '2026-09-10T23:00', 'end_dt' => '2026-09-11T01:00'], 'same day'],
+        ];
+    }
+
+    /**
+     * Each of these used to be a bare `return` — the page reloaded unchanged and
+     * the instructor had no way to tell the save had failed.
+     *
+     * @dataProvider invalidWindows
+     *
+     * @param array<string, string> $fields
+     */
+    public function testAddReportsEveryRejectedWindow(array $fields, string $expected): void
+    {
+        $_POST = array_merge([ 'usc_action' => 'add', 'duration_minutes' => '30' ], $fields);
+
+        $this->repository->shouldNotReceive('createFromWindow');
+        $this->repository->shouldReceive('findByInstructor')->once()->with(3)->andReturn([]);
+
+        $html = $this->render();
+
+        self::assertStringContainsString('notice-error', $html);
+        self::assertStringContainsString($expected, $html);
+    }
+
+    public function testAddRejectsAnOfferingTheInstructorDoesNotOwn(): void
+    {
+        // The REST endpoint always checked this; the admin form never did, so a
+        // crafted POST could tie a slot to another instructor's offering.
+        $_POST = [
+            'usc_action'       => 'add',
+            'start_dt'         => '2026-09-10T17:00',
+            'end_dt'           => '2026-09-10T18:00',
+            'duration_minutes' => '60',
+            'offering_id'      => '8',
+        ];
+
+        $this->offerings->shouldReceive('findById')->once()->with(8)->andReturn(null);
+        $this->repository->shouldNotReceive('createFromWindow');
+        $this->repository->shouldReceive('findByInstructor')->once()->with(3)->andReturn([]);
+
+        $html = $this->render();
+
+        self::assertStringContainsString('notice-error', $html);
+        self::assertStringContainsString('not available', $html);
+    }
+
+    public function testAddReportsHowManySlotsWereCreated(): void
+    {
+        $_POST = [
+            'usc_action'       => 'add',
+            'start_dt'         => '2026-09-10T17:00',
+            'end_dt'           => '2026-09-10T19:00',
+            'duration_minutes' => '60',
+            'recurrence'       => 'weekly',
+            'weeks'            => '41',
+        ];
+
+        $this->repository->shouldReceive('createFromWindow')->once()
+            ->with(Mockery::type(AvailabilitySlot::class), true, 41)
+            ->andReturn(range(1, 82));
+        $this->repository->shouldReceive('findByInstructor')->once()->with(3)->andReturn([]);
+
+        $html = $this->render();
+
+        self::assertStringContainsString('notice-success', $html);
+        self::assertStringContainsString('Added 82 bookable slots.', $html);
+    }
+
+    public function testAddReportsAFailedWrite(): void
+    {
+        // A valid window always splits into at least one slot, so an empty result
+        // means the inserts themselves failed.
+        $_POST = [
+            'usc_action'       => 'add',
+            'start_dt'         => '2026-09-10T17:00',
+            'end_dt'           => '2026-09-10T18:00',
+            'duration_minutes' => '60',
+        ];
+
+        $this->repository->shouldReceive('createFromWindow')->once()->andReturn([]);
+        $this->repository->shouldReceive('findByInstructor')->once()->with(3)->andReturn([]);
+
+        $html = $this->render();
+
+        self::assertStringContainsString('notice-error', $html);
+        self::assertStringContainsString('could not be saved', $html);
+    }
+
+    public function testSingleDeleteReportsAFailureToDelete(): void
+    {
+        $_POST = [ 'usc_action' => 'delete', 'slot_id' => '7' ];
+
+        $other = new AvailabilitySlot(instructorId: 4, startDt: '2026-07-08 09:00:00', endDt: '2026-07-08 10:00:00', id: 7);
+
+        $this->repository->shouldReceive('findById')->once()->with(7)->andReturn($other);
+        $this->repository->shouldReceive('findByInstructor')->once()->with(3)->andReturn([]);
+
+        $html = $this->render();
+
+        self::assertStringContainsString('notice-error', $html);
+        self::assertStringContainsString('could not be deleted', $html);
+    }
+
+    public function testBulkDeleteReportsBothHalvesOfAPartialResult(): void
+    {
+        $_POST = [ 'usc_action' => 'bulk_delete', 'slot_ids' => ['5', '7'] ];
+
+        $owned  = new AvailabilitySlot(instructorId: 3, startDt: '2026-07-08 09:00:00', endDt: '2026-07-08 10:00:00', id: 5);
+        $booked = new AvailabilitySlot(instructorId: 3, startDt: '2026-07-08 10:00:00', endDt: '2026-07-08 11:00:00', isBooked: true, id: 7);
+
+        $this->repository->shouldReceive('findById')->once()->with(5)->andReturn($owned);
+        $this->repository->shouldReceive('findById')->once()->with(7)->andReturn($booked);
+        $this->repository->shouldReceive('delete')->once()->with(5)->andReturn(true);
+        // The repository refuses a booked row, reporting it by returning false.
+        $this->repository->shouldReceive('delete')->once()->with(7)->andReturn(false);
+        $this->repository->shouldReceive('findByInstructor')->once()->with(3)->andReturn([]);
+
+        $html = $this->render();
+
+        self::assertStringContainsString('1 slot deleted.', $html);
+        self::assertStringContainsString('1 slot could not be deleted', $html);
+    }
+
     private function render(): string
     {
         ob_start();

tests/Unit/Availability/AvailabilityEndpointTest.php

@@ -8,6 +8,7 @@ use Mockery;
 use Unsupervised\Schedular\Availability\AvailabilityEndpoint;
 use Unsupervised\Schedular\Availability\AvailabilityRepository;
 use Unsupervised\Schedular\Availability\AvailabilitySlot;
+use Unsupervised\Schedular\Availability\WindowValidator;
 use Unsupervised\Schedular\Offering\OfferingRepository;
 use Unsupervised\Schedular\Tests\Unit\TestCase;
 
@@ -26,7 +27,7 @@ class AvailabilityEndpointTest extends TestCase
 
         $this->repository = Mockery::mock(AvailabilityRepository::class);
         $this->offerings  = Mockery::mock(OfferingRepository::class);
-        $this->endpoint   = new AvailabilityEndpoint($this->repository, $this->offerings);
+        $this->endpoint   = new AvailabilityEndpoint($this->repository, new WindowValidator($this->offerings));
     }
 
     public function testCreateRejectsWindowSpanningMultipleDays(): void

tests/Unit/Availability/AvailabilityRepositoryTest.php

@@ -49,6 +49,101 @@ class AvailabilityRepositoryTest extends TestCase
         self::assertSame(42, $result);
     }
 
+    public function testInsertReturnsZeroWhenTheWriteFails(): void
+    {
+        Functions\expect('current_time')->with('mysql')->andReturn('2026-04-01 12:00:00');
+
+        // wpdb::insert returns false on error, but insert_id still holds the
+        // previous statement's id — returning it made a failed write look like a
+        // successful one.
+        $this->db->shouldReceive('insert')->once()->andReturn(false);
+        $this->db->insert_id = 42;
+
+        $slot = new AvailabilitySlot(5, '2026-04-01 09:00:00', '2026-04-01 10:00:00', 30);
+
+        self::assertSame(0, $this->repo->insert($slot));
+    }
+
+    public function testCreateFromWindowOmitsChunksThatFailedToInsert(): void
+    {
+        Functions\when('current_time')->justReturn('2026-04-01 12:00:00');
+
+        // Three chunks; the middle write fails.
+        $results = [null, false, null];
+        $ids     = [11, 13];
+
+        $this->db->shouldReceive('insert')
+            ->times(3)
+            ->andReturnUsing(function () use (&$results, &$ids) {
+                $outcome = array_shift($results);
+
+                if (false !== $outcome) {
+                    $this->db->insert_id = array_shift($ids);
+                }
+
+                return $outcome;
+            });
+
+        $window = new AvailabilitySlot(5, '2026-04-01 09:00:00', '2026-04-01 10:30:00', 30);
+
+        self::assertSame([11, 13], $this->repo->createFromWindow($window));
+    }
+
+    public function testWeeklySeriesIsClampedToTheMaximum(): void
+    {
+        Functions\when('current_time')->justReturn('2026-04-01 12:00:00');
+
+        // The form's max is advisory; a hand-crafted POST could ask for any
+        // number, so the ceiling is enforced here.
+        $next = 1;
+        $this->db->shouldReceive('insert')
+            ->times(AvailabilitySlot::MAX_WEEKLY_OCCURRENCES)
+            ->andReturnUsing(function () use (&$next) {
+                $this->db->insert_id = $next++;
+
+                return null;
+            });
+        $this->db->shouldReceive('update')->once();
+
+        $first = new AvailabilitySlot(5, '2026-04-01 09:00:00', '2026-04-01 10:00:00', 60);
+
+        self::assertCount(
+            AvailabilitySlot::MAX_WEEKLY_OCCURRENCES,
+            $this->repo->createWeeklySeries($first, 10000)
+        );
+    }
+
+    public function testWeeklySeriesGroupsOnTheFirstRowThatActuallyWrote(): void
+    {
+        Functions\when('current_time')->justReturn('2026-04-01 12:00:00');
+
+        // The first insert fails. A failed row must not become the recurrence
+        // group (its id is 0), which would orphan every later occurrence.
+        $results = [false, null, null];
+        $ids     = [21, 22];
+
+        $this->db->shouldReceive('insert')
+            ->times(3)
+            ->andReturnUsing(function () use (&$results, &$ids) {
+                $outcome = array_shift($results);
+
+                if (false !== $outcome) {
+                    $this->db->insert_id = array_shift($ids);
+                }
+
+                return $outcome;
+            });
+
+        // The group is set from row 21 — the first that survived.
+        $this->db->shouldReceive('update')
+            ->once()
+            ->with('wp_us_availability', ['recurrence_group' => 21], ['id' => 21], ['%d'], ['%d']);
+
+        $first = new AvailabilitySlot(5, '2026-04-01 09:00:00', '2026-04-01 10:00:00', 60);
+
+        self::assertSame([21, 22], $this->repo->createWeeklySeries($first, 3));
+    }
+
     public function testCreateWeeklySeriesInsertsWeeklyAndSharesGroup(): void
     {
         Functions\when('current_time')->justReturn('2026-04-07 12:00:00');

tests/Unit/Availability/WindowValidatorTest.php

@@ -0,0 +1,143 @@
+<?php
+declare(strict_types=1);
+
+namespace Unsupervised\Schedular\Tests\Unit\Availability;
+
+use Mockery;
+use Unsupervised\Schedular\Availability\AvailabilitySlot;
+use Unsupervised\Schedular\Availability\WindowValidator;
+use Unsupervised\Schedular\Offering\Offering;
+use Unsupervised\Schedular\Offering\OfferingRepository;
+use Unsupervised\Schedular\Tests\Unit\TestCase;
+
+class WindowValidatorTest extends TestCase
+{
+    private OfferingRepository&Mockery\MockInterface $offerings;
+    private WindowValidator $validator;
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        $this->offerings = Mockery::mock(OfferingRepository::class);
+        $this->validator = new WindowValidator($this->offerings);
+    }
+
+    /**
+     * The reported bug: 5:30–6:00 PM submitted with the length select left on
+     * its 60-minute default. The window fits no lesson, so it used to persist
+     * nothing at all and say nothing.
+     */
+    public function testRejectsAWindowShorterThanTheLessonLength(): void
+    {
+        $result = $this->validator->validate(3, '2026-09-10 17:30', '2026-09-10 18:00', 60, 0);
+
+        self::assertInstanceOf(\WP_Error::class, $result);
+        self::assertSame('invalid_window', $result->get_error_code());
+        // The message names the length actually chosen, so the fix is obvious.
+        self::assertStringContainsString('60-minute', $result->get_error_message());
+    }
+
+    public function testAcceptsThatSameWindowAtAFittingLessonLength(): void
+    {
+        $result = $this->validator->validate(3, '2026-09-10 17:30', '2026-09-10 18:00', 30, 0);
+
+        self::assertInstanceOf(AvailabilitySlot::class, $result);
+        self::assertSame('2026-09-10 17:30:00', $result->startDt);
+        self::assertSame('2026-09-10 18:00:00', $result->endDt);
+        self::assertSame(30, $result->durationMinutes);
+        self::assertNull($result->offeringId);
+        self::assertCount(1, $result->splitByDuration());
+    }
+
+    /** @return array<string, array{string, string}> */
+    public static function badDateTimes(): array
+    {
+        return [
+            'empty start'        => ['', '2026-09-10 18:00'],
+            'empty end'          => ['2026-09-10 17:00', ''],
+            'unparseable start'  => ['tomorrow', '2026-09-10 18:00'],
+            'unparseable end'    => ['2026-09-10 17:00', 'not a date'],
+        ];
+    }
+
+    /** @dataProvider badDateTimes */
+    public function testRejectsUnusableDateTimes(string $start, string $end): void
+    {
+        $result = $this->validator->validate(3, $start, $end, 30, 0);
+
+        self::assertInstanceOf(\WP_Error::class, $result);
+        self::assertSame('invalid_datetime', $result->get_error_code());
+    }
+
+    public function testRejectsAnEndAtOrBeforeTheStart(): void
+    {
+        $backwards = $this->validator->validate(3, '2026-09-10 18:00', '2026-09-10 17:00', 30, 0);
+        $identical = $this->validator->validate(3, '2026-09-10 18:00', '2026-09-10 18:00', 30, 0);
+
+        self::assertInstanceOf(\WP_Error::class, $backwards);
+        self::assertInstanceOf(\WP_Error::class, $identical);
+        self::assertSame('invalid_datetime', $backwards->get_error_code());
+        self::assertSame('invalid_datetime', $identical->get_error_code());
+    }
+
+    public function testRejectsAWindowSpanningTwoDays(): void
+    {
+        $result = $this->validator->validate(3, '2026-09-10 23:00', '2026-09-11 01:00', 30, 0);
+
+        self::assertInstanceOf(\WP_Error::class, $result);
+        self::assertSame('invalid_window', $result->get_error_code());
+        self::assertStringContainsString('same day', $result->get_error_message());
+    }
+
+    public function testRejectsAnOfferingOwnedBySomeoneElse(): void
+    {
+        // Instructor 3 posting instructor 9's offering: accepting it would let a
+        // slot inherit another instructor's price and payment routing.
+        $this->offerings->shouldReceive('findById')->once()->with(8)
+            ->andReturn(new Offering(instructorId: 9, title: 'Theirs', kind: Offering::KIND_PRIVATE_LESSON, id: 8));
+
+        $result = $this->validator->validate(3, '2026-09-10 17:00', '2026-09-10 18:00', 60, 8);
+
+        self::assertInstanceOf(\WP_Error::class, $result);
+        self::assertSame('invalid_offering', $result->get_error_code());
+    }
+
+    public function testRejectsAnOfferingThatDoesNotExist(): void
+    {
+        $this->offerings->shouldReceive('findById')->once()->with(8)->andReturn(null);
+
+        $result = $this->validator->validate(3, '2026-09-10 17:00', '2026-09-10 18:00', 60, 8);
+
+        self::assertInstanceOf(\WP_Error::class, $result);
+        self::assertSame('invalid_offering', $result->get_error_code());
+    }
+
+    public function testKeepsAnOfferingTheInstructorOwns(): void
+    {
+        $this->offerings->shouldReceive('findById')->once()->with(8)
+            ->andReturn(new Offering(instructorId: 3, title: 'Mine', kind: Offering::KIND_PRIVATE_LESSON, id: 8));
+
+        $result = $this->validator->validate(3, '2026-09-10 17:00', '2026-09-10 18:00', 60, 8);
+
+        self::assertInstanceOf(AvailabilitySlot::class, $result);
+        self::assertSame(8, $result->offeringId);
+    }
+
+    public function testFallsBackToTheDefaultLessonLength(): void
+    {
+        $result = $this->validator->validate(3, '2026-09-10 09:00', '2026-09-10 10:00', 0, 0);
+
+        self::assertInstanceOf(AvailabilitySlot::class, $result);
+        self::assertSame(AvailabilitySlot::DEFAULT_DURATION_MINUTES, $result->durationMinutes);
+    }
+
+    public function testAcceptsTheDatetimeLocalFormTheFormActuallySubmits(): void
+    {
+        // The browser posts `Y-m-d\TH:i`, not the canonical space-separated form.
+        $result = $this->validator->validate(3, '2026-09-10T17:00', '2026-09-10T18:00', 60, 0);
+
+        self::assertInstanceOf(AvailabilitySlot::class, $result);
+        self::assertSame('2026-09-10 17:00:00', $result->startDt);
+    }
+}

tests/Unit/Policy/PolicyControllerTest.php

@@ -0,0 +1,256 @@
+<?php
+declare(strict_types=1);
+
+namespace Unsupervised\Schedular\Tests\Unit\Policy;
+
+use Brain\Monkey\Functions;
+use Mockery;
+use Unsupervised\Schedular\Policy\Policy;
+use Unsupervised\Schedular\Policy\PolicyController;
+use Unsupervised\Schedular\Policy\PolicyRepository;
+use Unsupervised\Schedular\Policy\PolicyService;
+use Unsupervised\Schedular\Policy\PolicyVersion;
+use Unsupervised\Schedular\Policy\PolicyVersionRepository;
+use Unsupervised\Schedular\Tests\Unit\TestCase;
+
+class PolicyControllerTest extends TestCase
+{
+    private PolicyRepository&Mockery\MockInterface $policies;
+    private PolicyVersionRepository&Mockery\MockInterface $versions;
+    private PolicyService&Mockery\MockInterface $service;
+    private PolicyController $controller;
+
+    protected function setUp(): void
+    {
+        parent::setUp();
+
+        $this->policies   = Mockery::mock(PolicyRepository::class);
+        $this->versions   = Mockery::mock(PolicyVersionRepository::class);
+        $this->service    = Mockery::mock(PolicyService::class);
+        $this->controller = new PolicyController($this->policies, $this->versions, $this->service);
+
+        $_POST = [];
+        $_GET  = [];
+
+        Functions\when('current_user_can')->justReturn(true);
+        Functions\when('check_admin_referer')->justReturn(true);
+        Functions\when('wp_unslash')->returnArg();
+        Functions\when('sanitize_text_field')->returnArg();
+        Functions\when('sanitize_title')->returnArg();
+        Functions\when('wp_kses_post')->returnArg();
+        $this->stubAutop();
+        Functions\when('sanitize_key')->alias(
+            static fn ($key) => strtolower((string) preg_replace('/[^a-zA-Z0-9_\-]/', '', (string) $key))
+        );
+        Functions\when('absint')->alias(static fn ($value) => abs((int) $value));
+        Functions\when('selected')->justReturn('');
+        Functions\when('wp_nonce_field')->justReturn('');
+        Functions\when('admin_url')->justReturn('admin.php');
+        Functions\when('add_query_arg')->alias(
+            static fn (array $args, string $url) => $url . '?' . http_build_query($args)
+        );
+        Functions\when('submit_button')->alias(static function (string $text = ''): void {
+            echo $text; // phpcs:ignore WordPress.Security.EscapeOutput.OutputNotEscaped -- test stub
+        });
+    }
+
+    public function testViewingAVersionRendersItsBodyAndAnEditForm(): void
+    {
+        $policy  = new Policy('Cancellation', 'cancellation', currentVersionId: 7, id: 4);
+        $version = new PolicyVersion(
+            policyId: 4,
+            versionNumber: 2,
+            body: '<p>Cancel 24 hours ahead.</p>',
+            status: PolicyVersion::STATUS_PUBLISHED,
+            publishedAt: '2026-07-01 09:00:00',
+            id: 7,
+        );
+
+        $_GET = [
+            'policy_id'  => '4',
+            'version_id' => '7',
+        ];
+
+        $this->policies->shouldReceive('findAll')->andReturn([$policy]);
+        $this->policies->shouldReceive('findById')->with(4)->andReturn($policy);
+        $this->versions->shouldReceive('findByPolicy')->with(4)->andReturn([$version]);
+        $this->versions->shouldReceive('findById')->with(7)->andReturn($version);
+
+        $html = $this->render();
+
+        self::assertStringContainsString('Cancel 24 hours ahead.', $html);
+        self::assertStringContainsString('value="edit_version"', $html);
+        self::assertStringContainsString('Save as New Draft', $html);
+    }
+
+    public function testVersionListLinksToTheViewer(): void
+    {
+        $policy  = new Policy('Cancellation', 'cancellation', currentVersionId: 7, id: 4);
+        $version = new PolicyVersion(policyId: 4, versionNumber: 2, body: 'text', id: 7);
+
+        $_GET = ['policy_id' => '4'];
+
+        $this->policies->shouldReceive('findAll')->andReturn([$policy]);
+        $this->policies->shouldReceive('findById')->with(4)->andReturn($policy);
+        $this->versions->shouldReceive('findByPolicy')->with(4)->andReturn([$version]);
+
+        $html = $this->render();
+
+        self::assertStringContainsString('page=us-policies&policy_id=4&version_id=7', $html);
+    }
+
+    public function testAVersionBelongingToAnotherPolicyIsNotShown(): void
+    {
+        $policy = new Policy('Cancellation', 'cancellation', id: 4);
+        $other  = new PolicyVersion(policyId: 9, versionNumber: 1, body: 'Someone else\'s policy', id: 7);
+
+        $_GET = [
+            'policy_id'  => '4',
+            'version_id' => '7',
+        ];
+
+        $this->policies->shouldReceive('findAll')->andReturn([$policy]);
+        $this->policies->shouldReceive('findById')->with(4)->andReturn($policy);
+        $this->versions->shouldReceive('findByPolicy')->with(4)->andReturn([]);
+        $this->versions->shouldReceive('findById')->with(7)->andReturn($other);
+
+        $html = $this->render();
+
+        self::assertStringNotContainsString('Someone else\'s policy', $html);
+        self::assertStringNotContainsString('value="edit_version"', $html);
+    }
+
+    public function testEditingAPublishedVersionCreatesANewDraftAndLeavesTheSourceUntouched(): void
+    {
+        $policy    = new Policy('Cancellation', 'cancellation', currentVersionId: 7, id: 4);
+        $published = new PolicyVersion(
+            policyId: 4,
+            versionNumber: 2,
+            body: '<p>Old text.</p>',
+            status: PolicyVersion::STATUS_PUBLISHED,
+            id: 7,
+        );
+        $draft = new PolicyVersion(policyId: 4, versionNumber: 3, body: '<p>New text.</p>', id: 11);
+
+        $_GET  = ['policy_id' => '4'];
+        $_POST = [
+            'usc_action' => 'edit_version',
+            'policy_id'  => '4',
+            'version_id' => '7',
+            'body'       => '<p>New text.</p>',
+        ];
+
+        $this->policies->shouldReceive('findAll')->andReturn([$policy]);
+        $this->policies->shouldReceive('findById')->with(4)->andReturn($policy);
+        $this->versions->shouldReceive('findByPolicy')->with(4)->andReturn([$draft, $published]);
+        $this->versions->shouldReceive('findById')->with(7)->andReturn($published);
+        $this->versions->shouldReceive('findById')->with(11)->andReturn($draft);
+
+        // A new draft is written; the edited version itself is never updated.
+        $this->service->shouldReceive('addDraftVersion')->once()->with(4, '<p>New text.</p>')->andReturn(11);
+        $this->versions->shouldNotReceive('updateBody');
+
+        $html = $this->render();
+
+        // The viewer follows through to the draft that was just created.
+        self::assertStringContainsString('New text.', $html);
+        self::assertStringContainsString('saved as a new draft version', $html);
+    }
+
+    public function testEditingADraftVersionUpdatesItInPlace(): void
+    {
+        $policy = new Policy('Cancellation', 'cancellation', id: 4);
+        $draft  = new PolicyVersion(
+            policyId: 4,
+            versionNumber: 3,
+            body: '<p>Old draft text.</p>',
+            status: PolicyVersion::STATUS_DRAFT,
+            id: 11,
+        );
+
+        $_GET  = ['policy_id' => '4'];
+        $_POST = [
+            'usc_action' => 'edit_version',
+            'policy_id'  => '4',
+            'version_id' => '11',
+            'body'       => '<p>Revised draft text.</p>',
+        ];
+
+        $this->policies->shouldReceive('findAll')->andReturn([$policy]);
+        $this->policies->shouldReceive('findById')->with(4)->andReturn($policy);
+        $this->versions->shouldReceive('findByPolicy')->with(4)->andReturn([$draft]);
+        $this->versions->shouldReceive('findById')->with(11)->andReturn($draft);
+
+        // An unpublished draft is rewritten rather than branched.
+        $this->versions->shouldReceive('updateBody')->once()->with(11, '<p>Revised draft text.</p>')->andReturn(true);
+        $this->service->shouldNotReceive('addDraftVersion');
+
+        $html = $this->render();
+
+        self::assertStringContainsString('Draft version 3 was updated', $html);
+    }
+
+    public function testEditingAnArchivedVersionCreatesANewDraft(): void
+    {
+        $policy   = new Policy('Cancellation', 'cancellation', currentVersionId: 9, id: 4);
+        $archived = new PolicyVersion(
+            policyId: 4,
+            versionNumber: 1,
+            body: '<p>Superseded text.</p>',
+            status: PolicyVersion::STATUS_ARCHIVED,
+            id: 7,
+        );
+        $draft = new PolicyVersion(policyId: 4, versionNumber: 4, body: '<p>Reinstated text.</p>', id: 12);
+
+        $_GET  = ['policy_id' => '4'];
+        $_POST = [
+            'usc_action' => 'edit_version',
+            'policy_id'  => '4',
+            'version_id' => '7',
+            'body'       => '<p>Reinstated text.</p>',
+        ];
+
+        $this->policies->shouldReceive('findAll')->andReturn([$policy]);
+        $this->policies->shouldReceive('findById')->with(4)->andReturn($policy);
+        $this->versions->shouldReceive('findByPolicy')->with(4)->andReturn([$draft, $archived]);
+        $this->versions->shouldReceive('findById')->with(7)->andReturn($archived);
+        $this->versions->shouldReceive('findById')->with(12)->andReturn($draft);
+
+        $this->service->shouldReceive('addDraftVersion')->once()->with(4, '<p>Reinstated text.</p>')->andReturn(12);
+        $this->versions->shouldNotReceive('updateBody');
+
+        $this->render();
+    }
+
+    public function testEditingAVersionOfAnotherPolicyIsRejected(): void
+    {
+        $policy = new Policy('Cancellation', 'cancellation', id: 4);
+        $other  = new PolicyVersion(policyId: 9, versionNumber: 1, body: 'Other', id: 7);
+
+        $_GET  = ['policy_id' => '4'];
+        $_POST = [
+            'usc_action' => 'edit_version',
+            'policy_id'  => '4',
+            'version_id' => '7',
+            'body'       => 'Injected text',
+        ];
+
+        $this->policies->shouldReceive('findAll')->andReturn([$policy]);
+        $this->policies->shouldReceive('findById')->with(4)->andReturn($policy);
+        $this->versions->shouldReceive('findByPolicy')->with(4)->andReturn([]);
+        $this->versions->shouldReceive('findById')->with(7)->andReturn($other);
+
+        $this->service->shouldNotReceive('addDraftVersion');
+        $this->versions->shouldNotReceive('updateBody');
+
+        $this->render();
+    }
+
+    private function render(): string
+    {
+        ob_start();
+        $this->controller->renderPage();
+
+        return (string) ob_get_clean();
+    }
+}

tests/Unit/Policy/PolicyEndpointTest.php

@@ -9,12 +9,14 @@ use Unsupervised\Schedular\Policy\Policy;
 use Unsupervised\Schedular\Policy\PolicyEndpoint;
 use Unsupervised\Schedular\Policy\PolicyRepository;
 use Unsupervised\Schedular\Policy\PolicyService;
+use Unsupervised\Schedular\Policy\PolicyVersion;
 use Unsupervised\Schedular\Policy\PolicyVersionRepository;
 use Unsupervised\Schedular\Tests\Unit\TestCase;
 
 class PolicyEndpointTest extends TestCase
 {
     private PolicyRepository&Mockery\MockInterface $policies;
+    private PolicyVersionRepository&Mockery\MockInterface $versions;
     private PolicyService&Mockery\MockInterface $service;
     private PolicyEndpoint $endpoint;
 
@@ -24,16 +26,43 @@ class PolicyEndpointTest extends TestCase
 
         Functions\when('sanitize_text_field')->returnArg();
         Functions\when('sanitize_title')->returnArg();
+        Functions\when('wp_kses_post')->returnArg();
+        $this->stubAutop();
 
         $this->policies = Mockery::mock(PolicyRepository::class);
+        $this->versions = Mockery::mock(PolicyVersionRepository::class);
         $this->service  = Mockery::mock(PolicyService::class);
         $this->endpoint = new PolicyEndpoint(
             $this->policies,
-            Mockery::mock(PolicyVersionRepository::class),
+            $this->versions,
             $this->service,
         );
     }
 
+    public function testIndexReturnsPlainTextBodiesAsParagraphs(): void
+    {
+        $policy  = new Policy('Cancellation', 'cancellation', currentVersionId: 7, id: 4);
+        $version = new PolicyVersion(
+            policyId: 4,
+            versionNumber: 2,
+            body: "Give 24 hours notice.\n\nLate cancellations are billed in full.",
+            status: PolicyVersion::STATUS_PUBLISHED,
+            id: 7,
+        );
+
+        $this->policies->shouldReceive('findAll')->andReturn([$policy]);
+        $this->versions->shouldReceive('findById')->with(7)->andReturn($version);
+
+        $body = $this->endpoint->index(new \WP_REST_Request([]))->get_data();
+
+        // The admin typed no markup, so the gate still receives real paragraphs
+        // rather than one unbroken run of text.
+        self::assertSame(
+            '<p>Give 24 hours notice.</p><p>Late cancellations are billed in full.</p>',
+            $body[0]['body']
+        );
+    }
+
     public function testCreateRejectsTitleLongerThanColumnLimit(): void
     {
         $this->service->shouldNotReceive('createPolicy');

tests/Unit/Policy/PolicyValueObjectsTest.php

@@ -27,6 +27,16 @@ class PolicyValueObjectsTest extends TestCase
         self::assertArrayHasKey('acceptance_scope', $policy->toArray());
     }
 
+    public function testAnEmptyBodyRendersAsNothingRatherThanAnEmptyParagraph(): void
+    {
+        \Brain\Monkey\Functions\when('wp_kses_post')->returnArg();
+        $this->stubAutop();
+
+        $version = new PolicyVersion(policyId: 4, versionNumber: 1, body: null);
+
+        self::assertSame('', $version->bodyHtml());
+    }
+
     public function testPolicyHandlesNullCurrentVersion(): void
     {
         $policy = Policy::fromRow((object) [

tests/Unit/TestCase.php

@@ -24,4 +24,17 @@ abstract class TestCase extends BaseTestCase
         Monkey\tearDown();
         parent::tearDown();
     }
+
+    /**
+     * Stub `wpautop()` with a minimal blank-line-to-paragraph transform — enough
+     * to assert that unmarked-up text reaches the page as real paragraphs.
+     */
+    protected function stubAutop(): void
+    {
+        Monkey\Functions\when('wpautop')->alias(static function (string $text): string {
+            $text = trim($text);
+
+            return '' === $text ? '' : '<p>' . implode('</p><p>', (array) preg_split('/\n\s*\n/', $text)) . '</p>';
+        });
+    }
 }

unsupervised-schedular.php

@@ -3,7 +3,7 @@
  * Plugin Name: Unsupervised Scheduler
  * Plugin URI:  https://git.unsupervised.ca/Unsupervised/unsupervised-scheduler
  * Description: Instructor/student lesson scheduling for WordPress.
- * Version:     1.2.3
+ * Version:     1.2.4
  * Requires at least: 6.2
  * Requires PHP: 8.1
  * Author:      Unsupervised
@@ -21,7 +21,7 @@ if (! defined('ABSPATH')) {
     exit;
 }
 
-define('USC_VERSION', '1.2.3');
+define('USC_VERSION', '1.2.4');
 define('USC_PLUGIN_FILE', __FILE__);
 define('USC_PLUGIN_DIR', plugin_dir_path(__FILE__));
 define('USC_PLUGIN_URL', plugin_dir_url(__FILE__));